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Air pollution includes particle-bound polycyclic aromatic hydrocarbons (PAHs), which eventually reach the placenta, triggering adverse perinatal outcomes through long-term exposure. Lately, air pollution has increased over the Metropolitan Area of Medellin-Colombia (MAMC), but its effects on pregnancy are still unknown. In this research, a real-time analysis of total airborne PAHs was made using a photoelectric sensor for residential places influenced by the industrial and traffic sources affecting the southern and northern MAMC during the second peak of the bimodal tendency for PM2.5 emissions in this region. Additionally, individual PAHs were analyzed by GC/MS coupled with pressurized hot water extraction methodology. The data were applied using an inhalation intake model to assess pregnancy exposure. The average concentration of PAHs in the southern MAMC was three times higher than in the northern MAMC, where the missed abortion rate has been 1.4 times higher according to the database. Previous research indicates that PAHs act as endocrine-disrupting chemicals (EDCs) during pregnancy and that even heavy congeners could reside in umbilical cord blood. Finally, the annual series of missed abortion rates in the MAMC exhibited a significant correlation with the annual average levels of PM2.5, which were associated with PAHs through correlation analysis (r2 = 0.69, p < 0.01). While this significant correlation does not imply causality, our results suggest an important connection between both variables, opening a gap for a deeper understanding of how regions with high PAH convergence influence the missed abortion rates in MAMC. [ABSTRACT FROM AUTHOR]

In recent years the literature on mobility of care has rapidly expanded, and the concept offers a powerful lens to highlight how everyday mobilities are organised, undertaken, and experienced in gendered ways. The concept can nonetheless benefit from further theoretical development. In this paper we enrich the mobility of care concept by drawing on influential conceptualisations of care from feminist theory and analysis of data collected during the COVID-19 lockdown among a group of 40 low-income women living in peri-urban areas of Itagüí, a municipality in the south of the Medellín metropolitan area, Colombia. Through this approach we first argue that relying on a taxonomy of trip purposes limits the understanding of the role of care in urban mobilities and risks underestimating the prevalence of mobility of care. Second, we suggest that activities of self-care also generate mobility of care and that their consideration allows practices and experiences of receiving care to be considered. Finally, we show how care activities are part of, and generate, intertwined mobilities and immobilities, and argue that rendering visible the full extent of mobilities of care demands that careful consideration be given to immobilities as well. [ABSTRACT FROM AUTHOR]

This study investigates spatio-temporal variations of PM10 mass concentrations and associated metal(oid)s, δ13C carbon isotope ratios, polycyclic aromatic hydrocarbons (PAHs), total organic carbon (TOC) and equivalent black carbon (eBC) concentrations over a half year period (from March 2017 to October 2017) in two residential areas of Medellín (MED-1 and MED-2) and Itagüí municipality (ITA-1 and ITA-2) at a tropical narrow valley (Aburrá Valley, Colombia), where few data are available. A total of 104 samples were analysed by using validated analytical methodologies, providing valuable data for PM10 chemical characterisation. Metal(oid)s concentrations were measured by inductively coupled plasma mass spectrometry (ICP-MS) after acid digestion, and PAHs concentrations were measured by Gas Chromatography-Mass Spectrometry (GC–MS) after Pressurised Hot Water Extraction (PHWE) and Membrane Assisted Solvent Extraction (MASE). Mean PM10 mass concentration ranged from 37.0 µg m−3 to 45.7 µg m−3 in ITA-2 and MED-2 sites, respectively. Al, Ca, Mg and Na (from 6249 ng m−3 for Mg at MED-1 site to 10,506 ng m−3 for Ca at MED-2 site) were the major elements in PM10 samples, whilst As, Be, Bi, Co, Cs, Li, Ni, Sb, Se, Tl and V were found at trace levels (< 5.4 ng m−3). Benzo[g,h,i] perylene (BghiP), benzo[b + j]fluoranthene (BbjF) and indene(1,2,3-c,d)pyrene (IcdP) were the most profuse PAHs in PM10 samples, with average concentrations of 0.82–0.86, 0.60–0.78 and 0.47–0.58 ng m−3, respectively. Results observed in the four sampling sites showed a similar dispersion pattern of pollutants, with temporal fluctuations which seems to be associated to the meteorology of the valley. A PM source apportionment study were carried out by using the positive matrix factorization (PMF) model, pointing to re-suspended dust, combustion processes, quarry activity and secondary aerosols as PM10 sources in the study area. Among them, combustion was the major PM10 contribution (accounting from 32.1 to 32.9% in ITA-1 and ITA-2, respectively), followed by secondary aerosols (accounting for 13.2% and 23.3% ITA-1 and MED-1, respectively). Finally, a moderate carcinogenic risk was observed for PM10-bound PAHs exposure via inhalation, whereas significant carcinogenic risk was estimated for carcinogenic metal(oid)s exposure in the area during the sampling period. [ABSTRACT FROM AUTHOR]

Canine distemper virus (CDV) is considered a reemerging disease-causing agent in domestic dogs because it presents high divergence among circulating strains worldwide. In Colombia, the South America-3 and South America/North America-4 lineages co-circulate in domestic dogs, both in the Medellin metropolitan area. In this paper, two full CDV genomes from each viral lineage circulating in Medellin were sequenced; we explored the phylogenetic relationship with the available genome sequences; we described the presence of CDV mutations in the South America-3 and South America/North America-4 lineages associated with adaptation to human cells and a crossing of the species barrier and pathogenicity; and we established the evolutionary rates and time of the closest common ancestor for each gene and characterized the presentation of multiple genomic sites by positive selection. [ABSTRACT FROM AUTHOR]

Using modeling techniques as Ordinary Least Squares-OLS, this paper studies the main variables that affect service trip generation (STG) (production and attraction) by the service sector (e.g., maintenance, repairs) in commercial establishments located in urban areas of developing countries. Data obtained from Medellin Metropolitan Area (Colombia) origin–destination freight surveys conducted in 2017–2018 were used to analyze service trips for the first time in the region. This helped determine the number of produced and attracted service trips, average duration per service, most used modes of transport in service trips, and other characteristics that improve the understanding of how service trips work in urban areas This information might help in analyses of variables that mainly influence STG. To this effect, the authors estimated more than 30 service trip production and attraction models for establishments; these models depend on independent variables, such as employment, and establishment's area. Finally, the freight community will benefit from these models because transport planners would analyze service trips as part of the freight and service activities in urban areas to contribute to improve the mobility using the models to plan better the transportation in the areas. [ABSTRACT FROM AUTHOR]

• Market segmentation is useful for formulating adequate, sustainable mobility policies. • Segmentation should consider individual differences in attitudes and perceptions. • We identified three groups: Traditionalists, Green Conscious and All Matters. • We proposed sustainable strategies considering the heterogeneities of each group. This paper draws attention to the need for formulating tailored, sustainable transport policies considering heterogeneity in the population regarding their preferences and attitudes. In this regard, we propose a market segmentation for incentivising sustainable transport policies. Our analysis builds from the responses of 1,041 car owners towards environmentally friendly transport alternatives in a survey issued in the five largest Colombian metropolitan areas: Bogotá, Medellín, Cali, Barranquilla, and Bucaramanga. Using the collected data, we estimated a Multiple Indicators Multiple Causes (MIMIC) model to evaluate individual attitudes towards the environment, green transport policies, car use, and technology. A cluster analysis based on the MIMIC results identified three groups: Traditionalists, Green Conscious and All Matters. Results make the contradiction between car attachment and environmental concern evident. The lower the environmental concern, the higher the attachment to the car. However, the differences between Traditionalists and All Matters are less pronounced. Finally, we proposed sustainable strategies considering the heterogeneities of each group, analysed the implications of developing custom-made actions and marketing strategies for promoting sustainable transport policies, considering the interests and characteristics of each targeted group in the population. [ABSTRACT FROM AUTHOR]

Through the example of Ciudadela Nuevo Occidente, a large social housing district in Medellín, this article describes a process that primarily involves co-learning and micro-negotiations that help produce the cognitive alignment necessary to the management of services. The hypothesis put forward in this article is that the frictions caused by the residents’ difficulties in adapting to the socio-economic, cultural and cognitive frameworks of their new environment, imposed by urban modernisation running processes, engender forms of service co-production that ultimately strengthen the utility’s capacity to extend and adapt its delivery model while enhancing the quality of services. [ABSTRACT FROM PUBLISHER]