High-density Residential Areas Research Articles

Urban micro-scale street thermal comfort prediction using a ‘graph attention network’ model

Outdoor thermal comfort (OTC) directly affects human behavior and building operations. It is also a key factor in the achievement of smart living. When modeling OTC, existing studies tend to reduce the computational burden by conceptualizing urban spatial elements (e.g., buildings, streets) as static entities without considering the intricate dynamics of their synergistic influence. This research presents an innovative network-based framework for urban micro-scale street OTC prediction. The proposed graph attention network (GAT), in conjunction with building energy modeling (BEM), treating building clusters as graph nodes and streets as edges, capturing the interrelations between urban spatial elements, and modeling the street's universal thermal climate index (UTCI) at different time periods. The GAT model is trained and tested using simulated data from representative high-density residential areas in Hong Kong. Its performance is evaluated against an artificial neural network (ANN) model that disregards interrelations among urban spatial elements. Results demonstrate that, compared to the ANN model, the GAT model achieves an improvement in overall mean absolute error (MAE) of 37.5 %, root mean square error (RMSE) of 36.07 %, and correlation coefficient (r) of 10.58 %. Furthermore, the GAT model can better predict situations with significant amplitude changes and rapid frequency variations.

Air-conditioning anthropogenic heat in high-density residential areas: Spatial patterns and impacts

The overheated urban environment has drastically increased air-conditioning (AC) usage, which induces extensive heat emissions from outdoor units. This phenomenon is more adverse in high-density residential areas as the air-conditioning anthropogenic heat (ACAH) would further cause localized heat accumulation in canyons, negatively impacting AC energy consumption and residents’ comfort. While previous research has explored the impact of ACAH on urban canyons, there is a lack of studies that systematically investigate the pattern, impacts, and mitigations of ACAH at a refined scale in high-density residential areas. This study aims to investigate the temperature distribution under ACAH and quantify its impact on cooling energy consumption and pedestrian thermal discomfort. High-density residential areas were categorized by different heights of buildings and directions of outdoor unit placement. Numerical simulations were conducted to study ambient temperature distribution. Results showed that the worst heat accumulation was at the windward position of the AC outdoor unit, and the outdoor temperature on the middle floor was 2.3 °C higher than that on the upper floor, resulting in a higher energy consumption of 6.3 W/m2. The worst case with taller windward buildings caused 55 % of the pedestrian areas to be more uncomfortable. Mitigation strategies were also proposed from multiple perspectives, including heat source optimization (e.g., cross-layout of AC outdoor units) and offering subsidies for AC electricity consumption gaps. The study provides a systematic research perspective on spatial heat accumulation patterns in high-density residential areas, which is instructive for mitigating urban warming and promoting sustainable urban development.

Daylight Availability of Living Rooms in Dense Residential Areas under Current Planning Regulations: A Cross-Region Case Study in China

After the pandemic, as it becomes more feasible to study and work from home, the quality of residential daylighting has attracted increasing attention. With the rapid growth of high-density residential areas, China is confronted with the incoordination between site planning and interior daylight availability across a wide region. Therefore, this paper investigates the applicability of planning regulations for daylight availability in dense residential areas under different climates across China, with the aim of providing data to optimize design strategies. ClimateStudio and ALFA were used to calculate the daylight factor (DF), daylight illuminance, spatial daylight autonomy (sDA), useful daylight illuminance (UDI), and melanopic equivalent daylight illuminance (m-EDI) of living rooms in four practical mixed housing estates in different Chinese daylight climate zones. The results showed that most of the studied units failed to meet current standards of DF and sDA300,50% for residence. However, more than half of these units still had high potential for UDI and met the recommendation of m-EDI by daylight only. The results verified the importance of integrative consideration of the local daylight climate and interior unit design for residential area layout planning. Finally, this paper suggests two topics for further exploration to bridge the gap between area planning and interior daylight availability in dense residential areas.

The spatial and social correlates of neighborhood morphology: Evidence from building footprints in five U.S. metropolitan areas.

Recent advances in quantitative tools for examining urban morphology enable the development of morphometrics that can characterize the size, shape, and placement of buildings; the relationships between them; and their association with broader patterns of development. Although these methods have the potential to provide substantial insight into the ways in which neighborhood morphology shapes the socioeconomic and demographic characteristics of neighborhoods and communities, this question is largely unexplored. Using building footprints in five of the ten largest U.S. metropolitan areas (Atlanta, Boston, Chicago, Houston, and Los Angeles) and the open-source R package, foot, we examine how neighborhood morphology differs across U.S. metropolitan areas and across the urban-exurban landscape. Principal components analysis, unsupervised classification (K-means), and Ordinary Least Squares regression analysis are used to develop a morphological typology of neighborhoods and to examine its association with the spatial, socioeconomic, and demographic characteristics of census tracts. Our findings illustrate substantial variation in the morphology of neighborhoods, both across the five metropolitan areas as well as between central cities, suburbs, and the urban fringe within each metropolitan area. We identify five different types of neighborhoods indicative of different stages of development and distributed unevenly across the urban landscape: these include low-density neighborhoods on the urban fringe; mixed use and high-density residential areas in central cities; and uniform residential neighborhoods in suburban cities. Results from regression analysis illustrate that the prevalence of each of these forms is closely associated with variation in socioeconomic and demographic characteristics such as population density, the prevalence of multifamily housing, and income, race/ethnicity, homeownership, and commuting by car. We conclude by discussing the implications of our findings and suggesting avenues for future research on neighborhood morphology, including ways that it might provide insight into issues such as zoning and land use, housing policy, and residential segregation.

Biophilic Experience in High-Rise Residential Areas in China: Factor Structure and Validity of a Scale

The increasing popularity of high-rise, high-density residential areas in urban environments has brought about problems such as isolation from nature and increasingly depauperate ecological conditions, and consequently, adverse effects on residents’ health and environmental sustainability. Therefore, creating a high-quality biophilic living space environment is key to solving this conflict, considering the health benefits that nature brings to people. However, there are currently no appropriate assessment tools to measure the biophilic living environment of high-rise residential areas. In response, we have developed an environment assessment scale for measuring the Biophilic Experience in High-Rise Residential Areas (BornA) based on resident experiences. Semi-structured interviews were conducted to identify the measurement items relevant to their biophilic living experiences and behaviors. Exploratory factor analysis and confirmatory factor analysis were performed to identify the scale’s structure and examine its reliability and validity. The study resulted in the development of an 18-item BornA, comprising five dimensions: natural landscape, natural interaction, cultural identity, neighborhood interaction, and personal space. The BornA contributes to the assessment of the biophilic living space environment in high-rise residential areas from the perspective of resident behavior and perception, identifying health intervention environments for sample populations and understanding how the residential environment affects residents’ health.

A fuzzy TOPSIS-based approach for prioritizing low-impact development methods in high-density residential areas.

The study successfully implemented six low-impact development (LID) methods to manage surface runoff in urban areas: green roof, infiltration trench, bio retention cell, rain barrel, green roof combined with infiltration trench, and rain barrel combined with bio-retention cell. Each method has unique benefits in mitigating surface runoff effects in urban environments. The following four indicators were used to evaluate the methods: runoff volume reduction, peak runoff flow rate reduction, economic sustainability, and social sustainability. The study, which lasted approximately 4 months, was conducted in an eastern Tehran metropolis residential area with a mix of old and new buildings. The SWMM model determined runoff volume and peak flow values, and a price analysis list determined the economic index. Local experts completed 25 questionnaires to evaluate the social index. Fuzzy TOPSIS multi-indicator decision criteria were used to prioritize LID methods, and the Rain barrel + Bio retention cell combined scenario emerged as the best option based on all four criteria. The method reduced peak runoff flow by 23.1-66.1% under rainfall with 10-year return periods. The green roof + infiltration trench method had the highest percentage reduction of 2,737 m3, while the infiltration trench had the lowest reduction of 273 m3.

Revisiting a de-Humanized Shanghai: Speculative Realism in Zhou Ming’s Contemporary Object-Oriented Materialist Documentary Photography

This paper explores the cultural operations of Zhou Ming’s photography (b.1960), which was aimed at exploring the deeper changes that have gripped the unstoppable urban renewal of Shanghai. His photo-essay Shanghai: An Alternative View (2000–2005), showcases the absurd and incongruous organic and inorganic spaces devoted to new points of view about the ruins that lay behind an assortment of high inner-city density residential areas situated in the Zhabei, Huangpu, and Houkou districts. Zhou Ming’s drive to de-humanize his apparent humanist photography through everyday objects and other signage found during his walking practices, also reveals multiple surrealist metaphoric representations between the materiality of the city and a slanted exaggeration of reality. His documentary camera sets out an ontological shift vis-à-vis the incidence of the everyday ‘found objects’, in which the privilege of humans over objects disappears. The aim of this article is to demonstrate how the photographer’s speculative aesthetics raises the need to redefine Chinese contemporary photography with theories linked to object-oriented ontologies and in general, to new materialism. This can be interpreted as a historical-cultural consolidation of media continuum that also embraces pre-photographic practices that can liberate objects and subjects from ‘sensitive’ content in a post-socialist reality.

Comparative Analysis of Thermal Comfort in Residential Buildings: A Study of the impact of Urban Density, Height, and Layout Patterns in the Context of Dhaka

The thermal environment of residential spaces significantly influences residents’ physical and emotional well-being, affecting daily activities and overall quality of life. With a growing global emphasis on sustainability, energy efficiency, and healthy living understanding how architectural and urban elements impact thermal comfort becomes crucial. This study focuses on Dhaka, Situated in a tropical monsoon climate, this context presents unique challenges for ensuring thermal comfort within structures. The research conducts a comparative analysis of two residential structures with different layout configurations but similar orientations, situated in diverse urban settings with varying levels of density, exposure and openings. Investigating the influence of urban density, adequate openings, shading within the plan layout, and vertical positioning of structures on residents’ thermal comfort, the study employs extensive field data collection, observation, questionnaire survey and simulation. The findings indicate that high-density residential areas offer advantages such as reduced direct heat intake and loss, yet may encounter challenges including limited natural ventilation and increased heat absorption, resulting in elevated indoor temperatures. Conversely, low-density areas with open spaces benefit from enhanced natural ventilation and reduced heat accumulation, leading to improved thermal comfort, particularly in hot and humid conditions. This paper underscores the significance of considering architectural and urban aspects in residential buildings in Dhaka’s context to ensure the thermal comfort and well-being of residents. By addressing these factors, designers and urban planners can contribute to creating healthier and more sustainable living environments amidst changing climatic conditions.

Tuberculosis Mortalities Among In-patients at a Tertiary Hospital in Zambia Between 2018 and 2019 - The Spectrum of Clinical Presentations

Background: Tuberculosis (TB) has remained one of the most important public health diseases and a leading cause of mortality from a single infectious agent in the world. In-patient mortalities have remained relatively high despite massive investment towards TB elimination. This prompted us to undertake a TB mortality review aimed at understanding the spectrum of clinical presentations in TB mortalities among in-patients in a local hospital set up in Zambia.
 Methods: Files of 74 in-patient TB related mortalities that had occurred at Kitwe Teaching Hospital over a 12-month period between June 2018 and June 2019 were audited using a structured questionnaire. The data was analyzed using SPSS v 16.0 statistical software while descriptive statistics and cross tabulation was used to determine the frequencies and cross relationships among the variables followed by univariate logistic regression whose significance was set at a p-value of 0.05 and a 95 percent confidence interval. Variables that were found to be significant at univariate logistic regression were fitted into the multivariable logistic regression.
 Results: The audit revealed that 50 (67.6%) of the files were for male patients with a mean age of 39.2 ± 11.6 years. 60(80%) were HIV positive, 60(80%) resided in high-density residential areas. On presentation to hospital, the commonest symptoms included productive cough and fever [31(41.9%) and 30(40.5%) respectively]. HIV positive male patients were presenting in hyperdynamic state (mean pulse rate of 117.2 ± 32.4 per minute, p = .001) and HIV positive females presented with mean arterial pressure (72.3 ± 19.5 mmHg, p = .002). Other findings included signs of multi-organ involvement [hypoalbuminemia 9(12.2%), deranged renal function 8(10.8%) and deranged liver enzymes 9(12.2%)] before mortality occurred.
 Conclusion: The spectrum of clinical presentations among in-patients with TB in a tertiary hospital include the following; male gender, age younger than 50 years, being HIV positive, residing in a high-density residential area and presenting with unstable hemodynamics. There is a need to focus strategies targeted at strengthening early recognition of clinical instability among admitted TB patients for at-risk populations, including young to middle aged males who are HIV positive.

Observed Equity and Driving Factors of Automated External Defibrillators: A Case Study Using WeChat Applet Data

Out-of-hospital cardiac arrest (OHCA) causes a high mortality rate each year, which is a threat to human well-being and health. An automated external defibrillator (AED) is an effective device for heart attack-related diseases and is a panacea to save OHCA. Most relevant literature focuses on the spatial distribution, accessibility, and configuration optimization of AED devices, which all belong to the characteristics of the spatial distribution of AED devices. Still, there is a lack of discussion on related potential influencing factors. In addition, analysis of AED facilities involving multiple city comparisons is less considered. In this study, data on AED facilities in two major cities in China were obtained through the WeChat applet. Then, the AED equity at the city and block scales and its socioeconomic factors were analyzed using the Gini coefficient, Lorenz curve, and optimal parameters-based geo-graphical detector (OPGD) model. Results show that the number of AEDs in Shenzhen was about eight-times that of in Guangzhou. The distribution of AEDs in Shenzhen was more equitable with a global Gini of 0.347, higher than that in Guangzhou with a global Gini of 0.504. As for the determinants of AED equity, residential density was the most significant determinant in both Guangzhou and Shenzhen from the perspective of individual effects on AED equity. Differently, due to the aging population in Guangzhou, the proportion of the elderly in blocks was influential to local AED equity. The local economic development level was crucial to local AED equity in Shenzhen. The results of the interaction detector model illustrate that relatively equitable AED distributions were found in the high-density residential areas with a balance of employment and housing, high-aging residential areas, and high-mobility residential areas in Guangzhou. The area with a high level of local economic development, dense population, and large mobility was the area with a relatively equitable distribution of AEDs in Shenzhen. The results of this paper are conducive to understanding the equity of AEDs and its socio-economic determinants, providing scientific reference for the optimization and management of AEDs.

A. J. Veal and Awais Piracha: meeting the need for a rational basis for open space and recreation planning in new high density residential areas: the Recreational Activity Benchmark model, Australian Planner, 2022. A rebuttal

ABSTRACT Veal and Piracha propose an alternate approach to planning recreation provision in new high-density residential areas (NHDA’s) of Australian cities: the RAB or ‘Recreation Activity Benchmark’ (Veal and Piracha 2022). Sydney is used as a case study. This paper contends that the methodology has a range of substantive deficiencies and ignores other well-established planning approaches that have been developed, tested and refined through hundreds of plans prepared by in-house and consulting leisure planners over the past 50 years in Australia and detailed in a range of texts and planning manuals. In applying the Recreation Activities Benchmark (RAB), provision of physical leisure resources is made on the basis of ‘averaging’ the recreation activities that people pursue to determine what facilities they need in the wider city in which the NHDA occurs. The averages are then applied to a projected NHDA population. This review questions the lack of a philosophical and planning basis of the RAB; the need for the RAB methodology; what ‘average’ means in terms of recreation participation; how the average is ‘adjusted’ if sufficient space is not available; the fact that the average used in the methodology has been selected solely to avoid possible legal action by developers, and the fact that the RAB is no different to a provision ‘standard’, given the reliance on data that has inherent shortcomings. The rebuttal concludes by questioning the need for the methodology.

Balancing Economic Sustainability with Densification: A Case Study of Dhaka

Economically sustainable urban residential neighborhoods are characterized by adequate provision of physical infrastructure including transport facilities and utility services. The built urban fabric of residential areas of Dhaka has been undergoing densification operation over the past decades without considering the physical infrastructure capacity of these areas in terms of accessibility and provision of transportation and utility services. This intervention eventually exerted pressure on the existing infrastructure and caused negative externalities like traffic congestion, pollution, and water clogging. Thus, this paper aims to investigate the impact of densification on residential areas of Dhaka through the lens of economic sustainability. Seven residential areas from Old and New Dhaka that underwent various degreesof densification were selected as the study areas. Primary data was collected through a random sampling household questionnaire survey, fieldwork, and informal qualitative interviews with the residents and officials. Various published literature, newspaper articles, plans, and reports from government archives, Capital Development Authority (RAJUK), Dhaka South City Corporation (DSCC), and Dhaka North City Corporation (DNCC) provided the secondary data. The analysis is carried out in two parts. In the firstpart the impact of densification on accessibility to transportation facilities and utility services is analyzed in terms of availability of the services, distance to the bus stops, average travel time, modal choice, and residents’ satisfaction level. The second part explores the relationship between density and aspects of economic sustainability through Pearson’s correlation test. The findings revealed that public transportation is more accessible in lower-density areas than the higher-density residential areas owing to the road network pattern. A significant service delivery gap except for water supply was observed regarding the provision and quality of gas, electricity, sewerage, and garbage disposal services across all the study areas. Overall, density was found to have a negative association with the accessibility to physical infrastructures indicating that high-density residential areas of Dhaka do not have increased access to public transport and utility services which is contrary to the expected benefits of high-density living. A comprehensive density planning with an integrated sustainable transport plan needs to be formulated where viable public transport like Bus Rapid Transit (BRTs) systems and waterways may mitigate the situation from further worsening.

Spatial analysis of groundwater quality in Bulawayo, Zimbabwe: Geogenic and anthropogenic contributions

Over-exploitation of groundwater owing to urbanisation and industrialisation compromises its quality, spatially and temporally. The objective of this study was to analyse the spatial groundwater quality due to geogenic and anthropogenic activities in Bulawayo, Zimbabwe. Eighty boreholes were mapped and sampled for selected water quality parameters. The groundwater quality parameters that were adopted in this study were the temperature, electric conductivity, dissolved oxygen, pH, bicarbonate alkalinity, chloride, sodium, calcium, magnesium, sulphates, chlorides, potassium, iron, nitrates, fluoride, phosphates, arsenic, aluminium, zinc, strontium, barium and manganese. Groundwater samples were evaluated for drinking water suitability as per the 2011 World Health Organization (WHO) guidelines. Prediction of groundwater quality parameters at unsampled points was achieved by using the Inverse Distance Weighted interpolation method using Geographic Information Systems (GIS) software. Population, land use and geological data were superimposed onto the groundwater quality to generate integrated maps. There were noticeable distinctions in groundwater quality within different geological areas, particularly for fluoride, arsenic, sodium, calcium, chloride and strontium, signifying natural groundwater contamination. High levels of nitrate were detected near agricultural areas and in medium to high-density residential areas suggesting possible contamination from nitrogenous fertilizers and leakages from wastewater infrastructure respectively. The application of GIS to spatially map water quality, can be used by hydrogeologists and local authorities in planning, monitoring and protecting groundwater resources.

Health-integrated heat risk assessment in Australian cities

Extreme heat, also known as the silent killer that conceal its lethal effect behind heat-related deaths, has become one of the deadliest natural hazards globally. However, the evaluation of heat risks in many countries remains incomplete, overlooking an important component on population health conditions in the evaluation framework. Drawing on the IPCC's risk assessment framework, this study presents, for the first time, a comprehensive heat health risk assessment in Australian capital cities, consisting of three individual indexes—the heat exposure index, heat hazard index and heat vulnerability index—at the finest census unit, and an overall heat health risk index (HHRI). By involving health-related indicators in heat risk assessment, our evaluation takes into account people's sensitivity to heat in developing the heat health risk indexes. Using the HHRI, we identify high heat risk areas appearing primarily in higher density residential areas with some distances away from the inner cities. We also find that the inequity of demographic and socioeconomic characteristics, housing features, and built environment features exists in areas with different levels of heat risks. Our findings contribute not only to profiling heat risks in Australian cities, but also empirically advance our understanding of place-based risk reduction in the Southern Hemisphere by linking climate science with health and spatial science research.

The Peri-Urban Gentrification Process in Cisauk Subdistrict, Tangerang Regency, Indonesia

Gentrification is a phenomenon that occurs in many regions. Gentrification is characterized by the influx of more affluent residents into initially low-value areas. This influx increases the value of these areas, potentially leading to the displacement of people who cannot afford to remain in the neighborhood. This study aims to examine the cause and impacts of peri-urban gentrification in Cisauk District, Tangerang Regency. This study uses qualitative and remote sensing-based analysis to investigate gentrification's impact on six Cisauk sub-district villages. We used primary and secondary data for the analysis. The primary data was collected from observations, interviews, questionnaires, and Google Earth Engine data catalog to get Landsat 7 and 8 image-ries. The secondary was collected from the Central Bureau of Statistics. The Landsat data was used to identi-fy the change on the physical aspect, while the others were used to analyze the non-physical aspect. After-ward, positive and negative effects were explored, emphasizing residents' responses and adaptations. The re-sults showed that Cisauk Subdistrict faced a gentrification process driven by locational factors (i.e., proximity to toll road) and local government policies (i.e., spatial planning policy designating it as a high-density residential area). The positive impact of the gentrified area is that the region is developing economically much better, and many areas function better economically and so benefit the region and its people. On the other hand, the negative impacts of gentrified areas are that indigenous people are threatened with being forced to leave their villages, there are significant increases in land prices, and changes in people's social lives occur. To minimize the negative impact of gentrification, the government should promote the capacity of low-income households to access its benefits.

Modelling of land use and land cover changes and prediction using CA-Markov and Random Forest

We used the Cellular Automata Markov (CA-Markov) integrated technique to study land use and land cover (LULC) changes in the Cholistan and Thal deserts in Punjab, Pakistan. We plotted the distribution of the LULC throughout the desert terrain for the years 1990, 2006 and 2022. The Random Forest methodology was utilized to classify the data obtained from Landsat 5 (TM), Landsat 7 (ETM+) and Landsat 8 (OLI/TIRS), as well as ancillary data. The LULC maps generated using this method have an overall accuracy of more than 87%. CA-Markov was utilized to forecast changes in land usage in 2022, and changes were projected for 2038 by extending the patterns seen in 2022. A CA-Markov-Chain was developed for simulating long-term landscape changes at 16-year time steps from 2022 to 2038. Analysis of urban sprawl was carried out by using the Random Forest (RF). Through the CA-Markov Chain analysis, we can expect that high density and low-density residential areas will grow from 8.12 to 12.26 km2 and from 18.10 to 28.45 km2 in 2022 and 2038, as inferred from the changes occurred from 1990 to 2022. The LULC projected for 2038 showed that there would be increased urbanization of the terrain, with probable development in the croplands westward and northward, as well as growth in residential centers. The findings can potentially assist management operations geared towards the conservation of wildlife and the eco-system in the region. This study can also be a reference for other studies that try to project changes in arid are as undergoing land-use changes comparable to those in this study.

Coronavirus Disease of 2019 (COVID-19) and Household Food Security in High-Density Residential Areas of Lusaka: Experiences From Ng’ombe Settlement

Comparable to the rest of the world, African countries are orbiting from the health, economic and social effects of COVID-19. The continent’s administrations responded to COVID-19 guidelines by imposing restrictions to limit the spread of the virus. COVID-19 and measures responses to the pandemic undermine food production, processing and marketing but the most concerning experiences are on the demand-side, economic and physical access to food. Food and Agriculture Organization’s ( FAO) ‘four pillars’ availability, accessibility, stability and utilization provide a complete framework for analysing food security. However, the paper was looking at how people in high density residential areas are experiencing food security during COVID-19 period. The main aim was to assess the experiences of residents of high density urban residential areas of Lusaka in terms of household food security before and during COVID-19 pandemic era. The study used the embedded research design. Structured interviews were used to collect data from the respondents using questionnaires administered on a sample of 235 Ng’ombe residents. Key informants were selected purposively from Ng’ombe urban health Centre, Ng’ombe Catholic church, Food and Agriculture Organization (FAO), Ministry of Agriculture and World Food Programme (WFP) officials. Data was collected using semi-structured interviews with a tool called interview guide. The data was analyzed using descriptive statistic, paired t-test and chi-square using R statistical computing software and excel. The results were presented using tables, pie charts and graphs. The study revealed that Ng’ombe residents had a devastating experience during the COVID 19 era among which include reduction in income, hunger, job losses, skipped or reduced meal sizes and compromised diet. Also pinpointing areas for governments and other actors to intervene in the food system to protect the food security of households left vulnerable by COVID-19 for example empowering the affected households with money for businesses and jobs creation. Keywords: COVID-19, Food security, High density areas, dietary diversity

Correlation between caffeine and coprostanol in contrasting Amazonian water bodies

The evaluation of contamination by domestic sewage is relevant in the Amazon region; however, it has neither been well-developed nor accompanied by research or monitoring programs. In this study, caffeine and coprostanol as indicators of sewage were investigated in water samples from Amazonian water bodies that crisscross the city of Manaus (Amazonas state, Brazil) and cover regions with distinct main land uses such as high-density residential, low-density residential, commercial, industrial, and environmental protection areas. Thirty-one water samples were studied based on their dissolved and particulate organic matter (DOM and POM) fractions. Quantitative determination of both caffeine and coprostanol was carried out using LC-MS/MS with APCI in the positive ionization mode. The streams of the urban area of Manaus had the highest concentrations of caffeine (1.47–69.65 μg L−1) and coprostanol (2.88–46.92 μg L−1). Samples from the peri-urban Tarumã-Açu stream and from the streams in the Adolpho Ducke Forest Reserve showed much lower concentrations of caffeine (20.20–165.78 ng L−1) and coprostanol (31.49–120.44 ng L−1). Samples from the Negro River showed a wider range of concentrations of caffeine (20.59–873.59 ng L−1) and coprostanol (31.72–706.46 ng L−1), with the highest values found in the outfalls of the urban streams. Levels of caffeine and coprostanol were significantly positively correlated in the different organic matter fractions. The coprostanol/(coprostanol + cholestanol) ratio proved to be a more suitable parameter than the coprostanol/cholesterol one in low-density residential areas. Proximity to densely populated areas and the flow of water bodies appear to influence the caffeine and coprostanol concentrations, which was observed in their clustering in the multivariate analysis. The results indicate that caffeine and coprostanol can be detected even in water bodies that receive very low domestic sewage input. Therefore, this study revealed that both caffeine in DOM and coprostanol in POM represent viable alternatives for use in studies and monitoring programs even in remote areas of the Amazon, where microbiological analyses are often unfeasible.

Active transportation in high density residential areas in Lembah Pantai during pandemic COVID 19

Before the pandemic, most studies on active transportation focused on socioeconomic factors, how many cars people had, and how much it cost to own a car. Comfort, safety, and accessibility are the aspects of active transportation that have been talked about the most in previous studies. However, none of them have looked at active transportation as a way to increase the value of residential properties, whether or not the people who live there use active transportation. So, the right neighbourhood, which would have benefited from good planning and infrastructure, couldn't take advantage of the chance. With restrictions on movement and orders to work from home, the question is raised of whether different socioeconomic groups are well represented in active transportation. Even though residential developers and governments are putting more effort into making better amenities and infrastructure for active mobility, there is no evidence that the two are related. Nonetheless, active transportation is utilized to promote an active lifestyle and market properties. This study adds to an original case study evaluation of walkability and active transportation in Lembah Pantai by adding to what we know about active transportation.

Mapping Urban Heat Island Areas in Ibadan

Today, across the world many urban areas are experiencing higher temperatures compared to their surrounding rural areas; this difference in temperature is known as Urban Heat Island (UHI). UHI has created temperature hotspots in our urban centers which are known as UHI areas. This study maps Urban Heat Island areas in Ibadan using remotely sensed data for 1984, 2000 and 2011. Land Surface Temperature (LST) and land use land cover characteristics of Ibadan urban were examined. Normalized Difference Vegetation Index (NDVI) was computed for the study area. Correlation analysis was performed, and the results reveals that a negative relationship exist between LST and NDVI. Urban Heat Island (UHI) areas were defined using the land use land cover and LST for 1984, 2000 and 2011. The result further reveals that to map UHI areas, maximum LST and LULC conventionally regarded as UHI areas should be used, such as: high density residential areas, commercial/industrial area, and public/educational institution. The result presents an objective approach adopted to give us a detailed view of places that fall under UHI areas and account for their change through the study years. Based on findings, possible mitigation measures as means of controlling the menace of UHI were highlighted for the study area.