Search Results (53)

The flock formation of bird species is a crucial behavioral process that enables them to colonize urban areas. However, the factors influencing the structure and composition of ground-feeding bird flocks have not yet been analyzed. This study aimed to relate flock characteristics, including size, number, species richness, and composition, to local and landscape factors in the urban parks of Buenos Aires City, Argentina. Surveys of flocks were conducted in 16 parks during the breeding season, covering both mono-specific and mixed-species flocks. Flock numbers were positively correlated with tree, lawn, and bare ground cover but negatively associated with raptor presence in the parks. Flock species richness declined with increased noise and pedestrian traffic but rose in parks where raptors were present. The composition of species in flocks was linked to tree cover, noise, and the presence of raptors. While the Rock Dove (Columba livia) and the Rufous-bellied Thrush (Turdus rufiventris) were more abundant in parks with greater tree cover, the Eared Dove (Zenaida auriculata) and the Monk Parakeet (Myiopsitta monachus) showed increased abundance in more open parks. Zenaida auriculata and Columba livia experienced a decline in abundance in parks where raptors were present. Our findings indicate that resource availability and predation risk are crucial factors shaping flock formation in urban parks. Full article

The smart-city revolution has been promoted as the next step in urban development, leveraging technology to achieve enhanced development standards amid the increasingly complex challenges of urbanization. However, despite the implementation of more efficient urban services, issues regarding their tangible effects and impact on people’s lives remain unresolved. In this context, the concept of intelligent cities is seen as a necessary evolution of the smart-city paradigm, positioning human factors as the driving forces behind urban technological evolution. This integrative concept embodies advanced technology to enhance essential urban functions, with sustainability, equity, and resilience as macro-development goals. This study reviews the multifaceted dimensions of intelligent cities, from designing and deploying smart infrastructure to implementing citizen-centric decision-making processes. Additionally, it critically examines the digital divide and highlights the importance of equitable development policies as essential for enabling transformative urban change. By linking technological advancement to social issues, this article provides practical insights and case studies from the cities of Helsinki, Barcelona, and Buenos Aires, demonstrating that smart-city initiatives are still failing to bridge the equity service distribution gap. This comprehensive assessment approach ultimately serves as a reference for future evaluations of intelligent urban transformations. Full article

Urban parks are refuges for a diversity of birds in cities. Therefore, understanding the relationship between park structure and different bird species is essential to achieve nature-friendly park planning and management. However, the selection of foraging substrates by ground-feeding species has been very little explored. The aim of this study was to analyze the use and selection of foraging substrates by birds in urban parks in Buenos Aires City, Argentina. Between December 2020 and February 2021, 16 urban parks were visited. During each visit, focal observations of individuals feeding on different microhabitats were made. For ground-foraging species, the use of each substrate was then compared with its availability by means of contingency tests. A total of 38 species and 7823 foraging attempts were registered. The species with the most records were the Rufous-bellied Thrush (Turdus rufiventris), the Eared Dove (Zenaida auriculata), and the Rufous Hornero (Furnarius rufus). Most of the species foraged on ground substrates. Several species, such as the Thrush and the Picazuro Pigeon (Patagioenas picazuro), selected lawn and bare ground. The Monk Parakeet (Myiopsitta monachus) and the Cattle Tyrant (Machetornis rixosa) selected lawn, while the Eared Dove and the Picui Ground Dove (Columbina picui) selected bare ground. Some species such as the Picui Ground Dove and the Green-barred Woodpecker (Colaptes melanochloros) did not use impermeable surfaces. The results obtained revealed that not only is green cover necessary for birds in urban parks, but also other surfaces such as bare ground can favor native bird species. Full article

The 1742–1743 plague epidemic significantly impacted Santa Fe, a key city along the Royal Road (Camino Real), a vital colonial trade route connecting Buenos Aires and Lima. This study examines the epidemic’s demographic and socio-economic consequences in Santa Fe, focusing on excess mortality and its disproportionate impact on marginalized groups, such as Indigenous and African-descended populations. Utilizing parish records, census data, and archival sources, the research quantifies mortality rates during the epidemic and highlights the role of Santa Fe’s strategic position in facilitating the rapid spread of the disease. The findings underscore the intersection of systemic vulnerabilities and territorial dynamics shaped by Bourbon reforms, which exacerbated the epidemic’s effects. Furthermore, this study explores the resilience of local communities, emphasizing how cultural and religious practices contributed to recovery. By situating Santa Fe’s experience within the broader context of the Royal Road, this research provides a nuanced understanding of the complex interplay between epidemics, social structures, and demographic change in colonial Latin America, offering valuable insights for contemporary public health strategies. Full article

Leishmaniasis is a neglected tropical disease caused by protozoan parasites of the genus Leishmania. An estimated 700,000 to 1 million new cases occur annually. Current therapies are limited by high toxicity, cost, prolonged treatment period, and rising resistance in endemic regions. The Asteraceae family has emerged as a promising source of bioactive compounds with proven leishmanicidal activity. In this study, the assessment of the antileishmanial activity of Helianthus tuberosus and Vernonanthura squamulosa extracts, the isolation of the sesquiterpene lactones heliangin and glaucolide A, respectively, and the evaluation of the activity of the compounds were conducted. Dichloromethane extracts of H. tuberosus and V. squamulosa were active on Leishmania amazonensis promastigotes, inhibiting the replication of the parasites in 97.2 ± 3.1% and 89.1 ± 1.1%, respectively, at 100 μg/mL. Heliangin was active against promastigotes of L. amazonensis (IC₅₀ = 9.3 μM) and intracellular amastigotes (IC₅₀ = 0.8 μM), while glaucolide A exhibited moderate activity against promastigotes (IC₅₀ = 46.7 μM) and did not show activity against intracellular amastigotes. Based on these results, heliangin was further evaluated in an animal model of cutaneous leishmaniasis using BALB/c mice infected with L. amazonensis. Heliangin (8 mg/Kg), when administered in combination with Glucantime, significantly reduced lesion progression and parasite load compared to the vehicle-treated group (p < 0.001). These findings show that heliangin is a potential candidate for leishmaniasis treatment, especially in combination with therapeutic drugs. Full article

The 1742–1743 plague epidemic profoundly impacted populations along the Camino Real, the main colonial trade route connecting Buenos Aires and Lima, with Córdoba, Argentina, as a critical focal point. This research examines the multidimensional repercussions of the epidemic, emphasizing its demographic, social, and economic consequences. Utilizing parish records as primary sources, this study quantifies the excess mortality, revealing a dramatic increase, with death rates in Córdoba peaking at 12 times the pre-epidemic average in May 1743. Marginalized groups, particularly enslaved and Indigenous populations, were disproportionately affected, which exacerbated existing social inequalities. Through a comprehensive analysis of historical data, this study contributes to understanding epidemic responses in colonial Latin America, illuminating how public health crises intersect with demographic and socio-economic structures. The findings provide insights that are relevant to contemporary public health perspectives on crisis management and resilience, highlighting how historical epidemics offer valuable understanding into the social dynamics of health emergencies. Full article

Bengala, a steamer that sank in 1889 near Capo Rizzuto, Italy, was a relatively new vessel for its time, with an unusually short 18-year service life, given that steamers of the period typically operated for 30 to 40 years. Despite its brief history, SS Bengala played a significant role in the development of Italy’s young merchant navy, undergoing multiple ownership changes and serving various Italian shipping companies. Employed mainly along the route to Southeast Asia, it transported Italian migrants overseas and also participated in troop raids during the Italian military expedition to Eritrea in 1887. Despite its historical significance, no iconographic material has yet been found to depict SS Bengala, and archival research conducted in Italy and England has not uncovered any naval plans, photographs, or drawings of the ship. To overcome this gap, the authors employed new technologies and historical information to create a virtual reconstruction. This research combined archival sources with underwater surveys, including a detailed 3D survey by divers and archaeologists. Archival research, including consultation of official documents, provided critical information on the ship’s dimensions, superstructure, rigging, materials, and construction methods. The 3D modelling of the ship’s external hull, based on precise geometric data from the wreck site, offers a first step towards virtual reconstruction. The modelling is grounded in photogrammetric surveying techniques, ensuring high accuracy in the reconstruction process. The model can be used in augmented reality (AR) applications to enhance underwater exploration, allowing divers to visualise the reconstructed ship in its original environment. Additionally, it supports museum exhibits, interactive visualisations, and educational games, making it a valuable resource for engaging the public with maritime history and archaeology. Full article

Chlamydia psittaci is a bacterium that infects several species of birds and mammals. It is the causal agent of avian chlamydiosis and psittacosis in humans and it is globally distributed. Chlamydia psittaci is one of the main zoonotic pathogens transmitted by birds. In Argentina, there has been limited research on the prevalence and genetic variability of C. psittaci. The aim of this study was to detect and genotype C. psittaci using molecular techniques in birds living in Buenos Aires City, Argentina, during the period 2012–2015. A descriptive, observational, retrospective and cross-sectional study was carried out. A total of 983 bird samples submitted for diagnosis of avian chlamydiosis were analyzed. The frequency of C. psittaci was 12.54% and 7.89% in Psittaciformes and Columbiformes, respectively. A 348 bp region of the ompA gene was sequenced in positive samples. Molecular genotyping was performed through a Bayesian phylogenetic analysis. Of the 983 bird samples, 83 were positive for C. psittaci and 44 could be sequenced. The genotypes found were A, B, and E. Despite the high levels of host specificity, we found six psittacids with genotype B and one pigeon with genotype A, reflecting the affiliative interaction between Psittaciformes and Columbiformes. This study represents the first survey reporting the presence of C. psittaci in birds within the largest and most populous city in Argentina. Full article

Limited research from the Global South has examined pedestrian accessibility to key destinations, particularly while considering efficient and practical sidewalk-specific conditions. This study employs a case-based approach, scrutinising walking access to three central squares, Mexico City’s Zocalo, Lima’s Plaza San Martin, and Buenos Aires’ Plaza de la República, within a 10-min walking radius. Geographic Information Systems (GIS) and Google Street View (GSV) were leveraged to conduct a virtual street audit, assessing six microscale features influencing the walking experience (kerb ramps, pavement continuity, sidewalk width, well-maintained sidewalks, active uses, and green spaces). These data facilitated the construction of a genuine pedestrian network and allowed the assessment of three-tiered pedestrian accessibility models that comprised easy access, comfortable routes, and vibrant walks. The findings reveal significant spatial inequities in pedestrian access. About 10% of buildings near Mexico City’s and Lima’s central squares lack pedestrian accessibility due to inadequate and interrupted sidewalk and crosswalk infrastructure, disproportionately impacting those with mobility limitations. Conversely, Buenos Aires exhibits better pedestrian facilities, with accessible, comfortable, and lively routes reaching approximately 20% of buildings surrounding the Plaza de la República. These results underscore the significant disparities in street infrastructure and networks within these historic neighbourhoods, emphasising the imperative for more inclusive, pedestrian-friendly urban planning in Latin American cities. Full article

Background: Caries experience in Argentine children is quite high and no national data are present. Aim: This cross-sectional observational survey aimed to assess the oral health status of schoolchildren in Buenos Aires (CABA) using CTNI and to evaluate the ecological association between health inequalities and caries prevalence. Design: Data were collected, via a clustered procedure, during the 2016–2018 school years. Children were examined at school to determine dental status according to the CTNI performed under standardized conditions, using light, dental mirrors, WHO probes and magnification (2.5×). Secondary sources were used to acquire socio-demographic and epidemiological data. A hierarchical cluster analysis was carried out with the municipalities of the CABA as the dependent variable and the socio-demographic factors. Results: The study population consisted of 62,904 schoolchildren, 43,571 of whom were enrolled into the study. Total caries prevalence was 67.78% while severe caries prevalence was 28.29%, which was statistically associated with the year of the survey (p < 0.01). Four territorial conglomerates from a socio-epidemiological standpoint outline homogeneous areas of social risk; cluster 1 had the highest social risk. The prevalence of severe caries (CTNI 7–14) was highest in cluster 1 (44.7–53.2% of the population). Conclusion: The social inequalities between municipalities of the CABA were statistically associated with high inequalities in oral health needs. Full article

This study presents an analysis of NO₂ and CO emissions in Argentina, utilizing remote sensing data. This research aims to determine the spatiotemporal distribution of NO₂ and CO emissions from 2019 to 2021. It examines the influence of land use and cover on NO₂ and CO emissions using various climatic, anthropic, and natural indicators. The year with the highest CO and NO₂ concentration was 2020. NO₂ exhibited the highest concentrations in built-up urban areas and croplands, notably impacting the capital city and the northern region of Buenos Aires province. Also, CO concentration was influenced by anthropic variable distances to national route, mining extraction, power plants, airports, and urban index (UI). They were also influenced by climatic and natural variables (Palmer drought index, vapor pressure, maximum environment temperature, wind speed, DEM, humidity, and normalized difference vegetation index (NDVI)) for the different uses and land covers. NO₂ concentrations were influenced by anthropic (distance to airports, service stations, open dumpsites, power plants, and factories), climatic, and natural variables (Palmer drought index, vapor pressure, wind speed, and DEM) for the different uses and land cover. This research supports sustainable environmental management by guiding the development of effective emission mitigation strategies for improved community health and well-being. Full article

An “Innerburb” is an urban structure that emerged between the 1950s and 1980s, settled in rural areas, and is considered the first periphery of the Latin American city. This structure results from socio-spatial and territorial evolutionary processes, constituting the pinnacle of informal evolution. However, despite offering a comprehensive perspective on the informal problem, innerburbs have been scarcely reviewed in the literature. This article explores the Latin American innerburb by adopting as a method a comparative study of the public/private interface in the cases of San Cosme in Lima, Villa Rodolfo Ricciardelli in Buenos Aires and Vila Heliopolis in São Paulo, evaluating their adaptation and interconnection with the city through morphological indicators, using morphological mapping through satellite images as an analytical tool, and using Space Syntax as a topological approach in the analysis of connectivity and visibility indicators. The objective of the research is the detection of morphological patterns that alter the functioning of the public/private interface in innerburbs. The results show that the existence of impermeable facades, the lack of public spaces and the illegal appropriation in the development of informal practices are transgressive adaptability patterns at the micro-scale that affect the interface, drastically limiting the interconnection between the innerburb and the formal fabric, restricting its morphological openness and affecting the development of socioeconomic activities. As a discussion and conclusion, corrective measures for progressive improvement in innerburbs are established, focusing on the adaptability of housing and road space as a means of interconnection between the innerburb and the city. Full article

Nanoparticles composed of inorganic boron-containing compounds represent a promising candidate as ¹⁰B carriers for BNCT. This study focuses on the synthesis, characterization, and assessment of the biological activity of composite nanomaterials based on boron carbide (B₄C). Boron carbide is a compelling alternative to borated molecules due to its high volumetric B content, prolonged retention in biological systems, and low toxicity. These attributes lead to a substantial accumulation of B in tissues, eliminating the need for isotopically enriched compounds. In our approach, B₄C nanoparticles were included in composite nanostructures with ultrasmall superparamagnetic nanoparticles (SPIONs), coated with poly (acrylic acid), and further functionalized with the fluorophore DiI. The successful internalization of these nanoparticles in HeLa cells was confirmed, and a significant uptake of ¹⁰B was observed. Micro-distribution studies were conducted using intracellular neutron autoradiography, providing valuable insights into the spatial distribution of the nanoparticles within cells. These findings strongly indicate that the developed nanomaterials hold significant promise as effective carriers for ¹⁰B in BNCT, showcasing their potential for advancing cancer treatment methodologies. Full article

Urbanization is among the main factors of ecosystem transformation and threats to global biodiversity. Urban green spaces provide multiple services, being important for biodiversity and human well-being. However, the relationship between green spaces and forest birds has been scarcely studied in the Global South. In this work, we used citizen science data (eBird) to assess the variation in the species richness and composition of forest birds in two types of public urban green spaces characterized by different vegetation composition and management: parks and reserves. In general, reserves had more native and unmanaged vegetation than parks. We selected parks and reserves located in the coastal area of the Metropolitan Area of Buenos Aires, Argentina. Sampling effort was considered as the number of checklists for each site. The database allowed information to be extracted from 12 sites and 33 species. The most common species were the Green-barred Woodpecker (Colaptes melanochloros), the Narrow-billed Woodcreeper (Lepidocolaptes angustirostris), and the White-crested Tyrannulet (Serpophaga subcristata). Bird species richness was higher in reserves than in parks and was positively related to sampling effort. The forest bird species composition varied according to the type of green area and sampling effort. Species composition showed a significant nestedness, with the least rich sites being a subset of species from the richest sites. Reserves and sites with the highest sampling effort concentrated all species. The results obtained show the importance of urban reserves in the conservation of forest birds. Full article

Psittaciformes are one of the bird orders with the highest number of threatened species and the most marked declining population trends. At present, the lack of information on the population size, reproductive fraction, and productivity of most parrot populations makes it difficult to design effective conservation actions. In this study, we monitored a population of Burrowing Parrots (Cyanoliseus patagonus) breeding in urbanized habitats in the southwest of Buenos Aires province, Argentina. Every December and February from 2018 to 2023, we counted the individuals arriving at a single communal roost, located in the main park of Bahía Blanca city, which gathers all the parrots breeding in 18–22 colonies within a radius of 20 km. Censuses were conducted before (December) and immediately after the incorporation of juveniles into the flocks (February). Breeding pairs were also counted annually in the colonies, and the average annual productivity and the proportion of juveniles were estimated from surveys in pre-roosting and feeding areas in February. The non-breeding fraction approached half of the population with no statistically significant differences among years (range: 37–53%), and the breeding population showed little annual variation, with a minimum of 1363 and a maximum of 1612 breeding pairs. The proportion of juveniles in the flocks and the estimated productivity showed larger variations among breeding seasons. Our results add insight to the scarce information available on the breeding-to-non-breeding-population ratios in parrots, and birds in general, and show key breeding parameters for a species that is thriving well in urban habitats. Full article