Catchment Area Research Articles

Global Urbanization and Habitat Quality: Interactive Coercive Relationships

Urbanization is inevitably accompanied by drastic changes in regional land use and therefore presents an evident influence on ecosystems. Habitat quality (HQ) reflects the ability of a habitat to provide suitable conditions for the survival of an individual or population, and clarifying the interrelationships between urbanization level (UL) and HQ provides insights into sustainable urbanzation and ecosystems conservation. Much attention has focused on how urbanization related to HQ at multi-scales, but few studies have analyzed the interactive coercive relationships between UL and HQ on the global county level. To address this gap, we adopted the bivariate spatial autocorrelation and coupling coordination degree (CCD) model to determine their interactive coercive relationships at the county level globally. Results showed that the global average UL was 0.0807, 0.0838, and 0.0857 in 2000, 2010, and 2020, respectively, with a continuously increasing trend. The global average HQ was 0.6186, 0.6133, and 0.6111 for 2000, 2010, and 2020, reflecting opposite declining trends. The Moran’s I of population urbanization and HQ in 2000, 2010, and 2020 globally remained negative but showed an increasing trend, with values of −0.189, −0.228, and −0.254, respectively, while those of economic urbanization and HQ and land urbanization and HQ also remained negative and exhibited a similar increasing trend. The spatial autocorrelations for UL and HQ in different dimensions indicated that deserts and plateaus functioned as catchment areas with low UL and HQ. The CCD between UL and HQ in each county globally ranged from 0 to 0.70, while CCD between land urbanization and HQ was the most optimal at 0–0.90. The CCD between population urbanization and HQ was similar to that of economic urbanization in terms of spatial distribution. Nevertheless, the CCD of land urbanization in HQ exhibited the greatest degree of coordination among the three urbanization dimensions during the study period. These findings provided important support for sustainable urbanization and ecosystem protection globally.

Innovative Strategy for Rainwater Harvesting in Saline-affected Urban Areas: A Case Study of a Sports Complex in Delhi

Water scarcity remains a critical global challenge, requiring immediate, sustainable management strategies, particularly in areas with an increasing disparity between water supply and demand. In India, and especially in Delhi, this issue is acute. In response to growing environmental concerns and the urgent need for sustainable water resource management, rainwater harvesting has emerged as a practical and effective solution for water conservation. This study investigates the application of rainwater harvesting to sustainably support water needs for a sports complex located in a salinity affected region. The land, originally intended for agriculture, has been converted into a complex featuring hydro-landscape facilities, including swimming pools, water polo areas, diving pools, toddler pools, and leisure pools. These facilities require an initial water input of 6,754.5 m³ and an annual replenishment of 7,957.28 m³ due to evaporation and seepage. By calculating the total rainwater harvesting potential based on the runoff coefficient, annual rainfall intensity, and the complex's catchment area, the study reveals that 29,693.8 m³ of rainwater can be harvested annually, providing a surplus of 14,981.7 m³ of potable water. This analysis demonstrates the viability of designing sports complexes in saline areas using efficient land use and rainwater harvesting, and presenting a scalable model for sustainable water management in similar regions worldwide.

Timor-Leste: preliminary assessment of a rapidly eroding landscape in the Coral Triangle

Context Sedimentation in the rivers and on the coasts of Timor-Leste has increased since deforestation, affecting floods and probably living aquatic resources. Aims To provide scientifically based estimates of long-term and short-term erosion rates to assess the apparent role of deforestation, a topic that has not received sufficient quantitative attention in the Coral Triangle. Methods Short-term erosion rates have been estimated from regional relationships between river sediment yield and catchment areas and cosmogenic nuclides for long-term rates. An attempt has also been made to estimate changes in rates of delta progradation to determine whether recent increases have occurred following deforestation. Key results The major scientific finding is that reduction in vegetation cover for agriculture and timber harvesting, particularly in the mountains, increased sediment yield by factors up to 120, mainly by landsliding. And there has been a large amount of sediment exported to the delta and offshore from river-channel change. Implications Impacts on living resources are likely both in rivers and on the coast, but require assessment. Revegetation of hillslopes is likely to reduce these impacts and improve the livelihoods of local people.

The Impact of Storm Sewer Network Simplification and Rainfall Runoff Methods on Urban Flood Analysis

Due to the impact of climate change, the importance of urban flood analysis is increasing. One of the biggest challenges in urban flood simulations is the complexity of storm sewer networks, which significantly affects both computational time and accuracy. This study aimed to analyze and evaluate the impact of sewer network simplification on the accuracy and computational performance of urban flood prediction by comparing different rainfall runoff methods. Using the hyper-connected solution for urban flood (HC-SURF) model, two rainfall runoff methods, the SWMM Runoff method and the Surface Runoff method, were compared. The sewer network simplification was applied based on manhole catchment areas ranging from 10 m2 to 10,000 m2. The analysis showed that the computation time could be reduced by up to 54.5% through simplification, though some accuracy loss may occur depending on the chosen runoff method. Overall, both methods produced excellent results in terms of mass balance, but the SWMM Runoff method minimized the reduction in analytical performance due to simplification. This study provides important insights into balancing computational efficiency and model accuracy in urban flood analysis.

A Novel Rainfall Classification for Mapping Rainwater Harvesting: A Case Study in Kalar, Iraq

Increasing water demand driven by population growth and climate change strains water resources, especially in arid regions. The effectiveness of rainwater harvesting (RWH) as a viable solution is contingent upon the meticulous selection of appropriate sites. Contemporary efforts have increasingly utilized Geographic Information Systems (GIS) and remote sensing technologies to optimize the identification of ideal locations for implementing RWH infrastructure. However, inconsistencies in rainfall classification methodologies can compromise the accuracy of the resulted suitability maps. Consequently, a standardized approach to grading rainfall depth for mapping RWH sites becomes imperative. This study presents an innovative rainfall classification method tailored for both micro and macro catchment areas, offering a reliable and adaptable approach to rainfall analysis. By refining classification criteria, this method aims to improve the consistency and precision of RWH mapping, addressing a gap in existing methodologies and providing a more standardized approach. Through the application of FAHP and Fuzzy overlay techniques in ArcGIS 10.4, the study compares traditional rainfall classification with the proposed new classification method to assess RWH suitability in Kalar. The comparison highlights that the new rainfall classification-based map yielded higher accuracy and realism compared to traditional methods.

The Bioaccumulation of Potentially Toxic Elements in the Organs of Phragmites australis and Their Application as Indicators of Pollution (Bug River, Poland)

The bioaccumulation of potentially toxic elements (PTEs) in aquatic plants is critical in assessing the quality of aquatic environments and the risks associated with anthropogenic activities. This research involved using Phragmites australis as a bioindicator in a comprehensive assessment of the spatial variation in pollution within the Bug River catchment, employing advanced statistical methods to identify pollution sources. The study aimed to investigate the bioaccumulation of PTEs in different parts of the P. australis plant and to evaluate their suitability as bioindicators of contamination. Plant samples were collected from 32 locations in the Bug River catchment, and the concentrations of metals such as Cd, Pb, Cr, Ni, Zn, Cu, Fe, and Mn were determined by atomic absorption spectrometry. The results indicated that PTE accumulation was highest in the roots, underscoring their crucial role in monitoring metal concentrations. Metal concentrations differed based on land use within the catchment area, with the highest levels observed in urbanized regions, highlighting the significant impact of human activities like wastewater discharge and transport emissions. The highest concentrations were observed for Fe, Mn, and Zn, while Cd concentrations were notably elevated in agricultural areas. The analyses confirmed that P. australis serves as an effective bioindicator of heavy metal contamination and can be employed in long-term biomonitoring programs.

Interdisciplinary Research for the Delimitation of Catchment Areas of Large Deep Karstic Aquifers: Origin of the Thermal Springs of Alhama de Aragon and Jaraba (Spain)

The integration of different sources of geological and hydrogeological information and the application of interdisciplinary methods have informed the origin of the thermal springs of Alhama de Aragón and Jaraba, as well as other associated semi thermal springs (1200 L/s of combined flow, 711 L/s at over 30 °C), which is the main objective of this article. These springs come mainly from the autogenous recharge that occurs in the Cretaceous calcareous outcrops that border the Almazán Basin to the north, both in the Ebro Basin (Jalón Valley) and in the Duero Basin. The aquifer, shaped by upper Cretaceous limestones under the Palaeogene and Neogene rocks of the Almazán Basin, has extensive depths of more than 4000 m in the NE sector. This hydrostratigraphic unit has been affected by a generalized pre-Paleogene karstification that provides the main porosity to the aquifer. The underground flow moves in a NW–SE direction, crossing the Duero–Ebro divide, favoured by the topographic difference in elevation between the two basins. The regional flow is coherent with the progressive increase in temperature, infiltrating recharge water age (about 20–25 years in the semi-thermal springs, and more than 60 years in the Alhama and Jaraba springs), mineralization, and flow of the springs through which the system discharges. This issue is key to being able to design any sustainable conservation strategy in terms of quantity and quality of resources within the recharge area of the most important thermal springs in Spain. The Jaraba and Alhama de Aragón hot springs share the same or similar temperature, chemical composition, and geological contact of the spring. Their tritium isotopic composition and its evolution over time are practically the same. Their isotopic composition in D and 18O is also very similar. Both springs share the same recharge zone of similar altitude and constitute the end of flow tubes of similar length and flow rate.

Urban transformation of lakes and its impacts on a lake series: A case study of the yele mallappa shetty lake series Bengaluru, India.

The interconnected systems of lakes of Bengaluru, India, experience tremendous stress due to unsustainable urbanisation. Traditional lake-centric research approach struggles to capture and address this issue due to the cascaded nature of impacts in interconnected lake systems. Hence, this study assesses the impact of urbanisation on a lake series scale, focusing on the Yele Mallappa Shetty Lake series (YMSLS). Land use land cover change analysis (1993-2023) showed that in 1993, the YMSLS catchment area was dominated by open spaces (53.4%) and agriculture land and vegetation (35%), with built-up areas covering only 7.2%. By 2023, the built-up area has expanded to 34.6% and became the dominant land use. This rapid urbanisation has led to increased water surface area from wastewater influx, causing significant weed growth and water pollution in the lakes. Lake water quality assessment showed that faecal coliform, total coliform, dissolved oxygen, and biochemical oxygen demand levels exceeded standard limits with spatio-temporal variations driven by interconnectivity. Pollutant flushing during monsoon reduced pollution load in upstream lakes, but high wastewater inflow made downstream lakes, particularly the end lake, highly polluted but perennial. Increased water availability expanded the user base of the end lake, but traditional uses have declined and coping strategies of users, such as wastewater lift irrigation from the lake, became unsustainable. The study indicates that spatial interdependence and cascading effects necessitate a lake series approach for assessing the impacts of urbanisation on interconnected lake system, which is crucial for enhancing water security and preparedness for future extreme events.

Spatial Disparities in Access to Dialysis Facilities in Texas: An Analysis of End-Stage Renal Data in 1974–2020

Background/Objectives: This study investigates the spatial disparities in access to dialysis facilities across Texas. The objective is to analyze how urbanization and socio-economic/demographic factors influence these disparities, with a focus on differences between urban and rural areas. Methods: The enhanced two-step floating catchment area method is employed to calculate accessibility scores to dialysis facilities across the state. Additionally, Moran eigenvector spatial filtering is utilized to analyze the influence of urbanization and socio-economic/demographic factors on accessibility disparities. Results: The Moran eigenvector spatial filtering analysis revealed a significant level of spatial autocorrelation in accessibility scores, particularly highlighting disparities between urban and rural areas. Urban regions, especially major metropolitan areas, achieved higher accessibility scores due to the dense concentration of dialysis facilities. In contrast, rural areas, notably in western and northern Texas, exhibited lower accessibility, underscoring the challenges faced by residents in these regions. The model further identified urbanization and the percentage of the elderly population as critical covariates affecting accessibility, with urban counties showing higher accessibility and elderly populations in rural areas facing significant challenges. Conclusions: These findings emphasize the importance of considering spatial dependencies in healthcare accessibility studies. They suggest the need for targeted policy interventions to address the identified disparities, particularly in underserved rural regions, to improve access to dialysis facilities for vulnerable populations.

Hydrological Modeling of Krishna Upper Catchment Area of India Using Multisite Calibration and Validation of SWAT Model

Multisite calibration & validation of model reduces the uncertainty present in the model parameters and improve the SWAT model output. In the present study, an effort was made to set up SWAT model along with multisite calibration and validation for Kishna upper basin of India. A total of six gauging stations maintained by Central water commission across the area were selected for SWAT model calibration and validation. Sequential Uncertainty Fitting (SUFI-2) programme of SWAT-CUP (Calibration and Uncertainty Programme) was employed to calibrate the SWAT model. During sensitivity analysis of SWAT model, parameters which are highly sensitive that influences flow characteristics of different gauging station were identified. These parameters along with parameter range were used to calibration and validation of SWAT model each of the sub basins. Observed flow and predicted stream flows were compared with certain model performance indices. These indices indicated that for all six gauging stations, the SWAT model found to be very good. The performance indices like R2, NSE, RSR and PBIAS were ranged from 0.70 to 0.84, 0.67 to 0.76, 0.49 to 0.57 and -11.7 to 24.0% respectively during model calibration period and 0.70 to 0.93, 0.67 to 0.83, 0.41 to 0.58 and 8.5 to 22.9% respectively during model validation period. A good agreement between observed and simulated flows at all the gauging stations were observed. It can be concluded that SWAT model output was improved with multisite calibration and validation of the model.

Recent and future variability of the ice-sheet catchment of Sermeq Kujalleq (Jakobshavn Isbræ), Greenland

Abstract Knowledge of ice-sheet catchments is critical for mass-balance assessments, especially glacier-scale input–output budgets. This study explores variations in the catchment of Sermeq Kujalleq, or Jakobshavn Isbrø, Greenland. Six observation-based catchment delineations are evaluated along with a 16-member catchment ensemble calculated from ice-sheet models within the Ice Sheet Model Intercomparison Project for CMIP6 (ISMIP6). The ‘present-day’ ISMIP6 ensemble mean area was found to be $\sim 6.3\%$ larger than the mean of the observed catchments. Ensemble spreads were comparable in size, $\pm 12.3\%$ and $\pm 15.4\%$ , suggesting models are able to delineate the present-day catchment with the same degree of uncertainty as observational methods. The mean catchment area of a 13-member ISMIP6 ensemble shows temporal variation, increasing $\sim [ 2.7,\; \, 5.7,\; \, 9.1] \%$ under three ocean forcing scenarios and a RCP8.5 projection based on one GCM from 2015 to 2100, primarily as the southern catchment boundary migrates southward. This is interpreted as Sermeq Kujalleq exhibiting dynamic piracy, re-directing ice away from adjacent land terminating glaciers. For mass-balance assessments, present-day catchment delineation is more important than capturing the temporal evolution of individual catchments. However, the modeled temporal changes in catchment area are potentially underestimated, as the models exhibit insufficient acceleration of inland ice flow.

Burden of Respiratory Syncytial Virus-Associated Hospitalizations in US Adults, October 2016 to September 2023.

Respiratory syncytial virus (RSV) infection can cause severe illness in adults. However, there is considerable uncertainty in the burden of RSV-associated hospitalizations among adults prior to RSV vaccine introduction. To describe the demographic characteristics of adults hospitalized with laboratory-confirmed RSV and to estimate annual rates and numbers of RSV-associated hospitalizations, intensive care unit (ICU) admissions, and in-hospital deaths. This cross-sectional study used data from the RSV Hospitalization Surveillance Network (RSV-NET), a population-based surveillance platform that captures RSV-associated hospitalizations in 58 counties in 12 states, covering approximately 8% of the US population. The study period spanned 7 surveillance seasons from 2016-2017 through 2022-2023. Included cases from RSV-NET were nonpregnant hospitalized adults aged 18 years or older residing in the surveillance catchment area and with a positive RSV test result. Laboratory-confirmed RSV-associated hospitalization, defined as a positive RSV test result within 14 days before or during hospitalization. Hospitalization rates per 100 000 adult population, stratified by age group. After adjusting for test sensitivity and undertesting for RSV in adults hospitalized with acute respiratory illnesses, rates were extrapolated to the US population to estimate annual numbers of RSV-associated hospitalizations. Clinical outcome data were used to estimate RSV-associated ICU admissions and in-hospital deaths. From the 2016 to 2017 through the 2022 to 2023 RSV seasons, there were 16 575 RSV-associated hospitalizations in adults (median [IQR] age, 70 [58-81] years; 9641 females [58.2%]). Excluding the 2020 to 2021 and the 2021 to 2022 seasons, when the COVID-19 pandemic affected RSV circulation, hospitalization rates ranged from 48.9 (95% CI, 33.4-91.5) per 100 000 adults in 2016 to 2017 to 76.2 (95% CI, 55.2-122.7) per 100 000 adults in 2017 to 2018. Rates were lowest among adults aged 18 to 49 years (8.6 [95% CI, 5.7-16.8] per 100 000 adults in 2016-2017 to 13.1 [95% CI, 11.0-16.1] per 100 000 adults in 2022-2023) and highest among adults 75 years or older (244.7 [95% CI, 207.9-297.3] per 100 000 adults in 2022-2023 to 411.4 [95% CI, 292.1-695.4] per 100 000 adults in 2017-2018). Annual hospitalization estimates ranged from 123 000 (95% CI, 84 000-230 000) in 2016 to 2017 to 193 000 (95% CI, 140 000-311 000) in 2017 to 2018. Annual ICU admission estimates ranged from 24 400 (95% CI, 16 700-44 800) to 34 900 (95% CI, 25 500-55 600) for the same seasons. Estimated annual in-hospital deaths ranged from 4680 (95% CI, 3570-6820) in 2018 to 2019 to 8620 (95% CI, 6220-14 090) in 2017 to 2018. Adults 75 years or older accounted for 45.6% (range, 43.1%-48.8%) of all RSV-associated hospitalizations, 38.6% (range, 36.7%-41.0%) of all ICU admissions, and 58.7% (range, 51.9%-67.1%) of all in-hospital deaths. In this cross-sectional study of adults hospitalized with RSV before the 2023 introduction of RSV vaccines, RSV was associated with substantial burden of hospitalizations, ICU admissions, and in-hospital deaths in adults, with the highest rates occurring in adults 75 years or older. Increasing RSV vaccination of older adults has the potential to reduce associated hospitalizations and severe clinical outcomes.

Abstract 4136799: Disparities in Diagnosis and Treatment of Heterozygous Familial Hypercholesterolemia

Introduction: The prevalence of heterozygous familial hypercholesterolemia (HeFH) is 1:250. Untreated individuals have up to a 20-fold increased risk for premature coronary artery disease (CAD). In adults, low socioeconomic status (SES) individuals, bear a disproportionate share of the CAD burden. In this context, we sought to examine the association of social determinants of health and age at HeFH diagnosis and treatment. Methods: We performed a retrospective single-center study of children with HeFH who presented to the Lipid Heart Clinic at the Children’s Hospital of Philadelphia (2012-2022). The primary outcome was age at HeFH diagnosis. The secondary outcome was age at statin initiation. Multivariable linear regression models were used to examine the association between the primary exposure of interest, Child Opportunity Index (COI) and the outcomes. Secondary exposures included race, ethnicity, health insurance, and primary language. To explore potential referral bias, we compared the COI of the study cohort to that of the institution’s catchment area, defined as within a two-hour drive of the primary clinic. Results: We evaluated 577 patients. The median age at presentation was 12 (9, 14) years and the median LDL-C was 199 (169, 235) mg/dL; 58% were prescribed a statin with a median age of statin initiation of 13 (10, 15) years. The median COI for the cohort was 84 (62, 95). There was no association between COI, ethnicity, health insurance, or primary language and the age at HeFH diagnosis or statin initiation. On multivariable analysis, black race was associated with older age at HeFH diagnosis compared to white race (adjusted estimate 1.2 +/- 0.49 yrs, p = 0.014). There was no difference in age at statin initiation by race. Higher LDL-C, male sex, and lower BMI percentile were associated with younger age at statin initiation. The COI distribution of the study cohort was significantly different than that of the catchment area (p < 0.001). 70% of the study cohort were of high and very high COI compared to 57% of the catchment area. Conclusion: Black race was associated with older age at HeFH diagnosis, however, there were no disparities in age at statin initiation. The COI of the cohort was significantly higher than that of the catchment area suggesting that low COI populations are under-referred for HeFH evaluation. Future efforts should focus on improving barriers to universal screening and identifying obstacles to HeFH diagnosis and referrals.

Land-Use Impacts on Soil Erosion: Geochemical Insights from an Urban Drinking Catchment, South-Central Chile

We investigate the influence of land use and land cover (LU/LC) changes on soil erosion and chemical weathering processes within the Nonguén watershed in the Coastal Cordillera of south-central Chile. The watershed is divided into three sub-basins, each characterized by distinct LU/LC patterns: native forest and exotic plantations. A comprehensive geochemical analysis, including trace elements and lithium (Li) isotopes, was conducted on river water and suspended sediment samples collected from streams within these sub-basins to assess how land management practices, particularly plantation activities, influence the geochemical composition of river systems. Our results show that sub-basins dominated by exotic plantations exhibit significantly higher concentrations of major and trace elements in suspended sediments compared to sub-basins dominated by native forests. The elevated trace element concentrations are primarily attributed to increased physical erosion due to forestry activities such as clear-cutting and soil disturbance, which enhance sediment mobilization. Notably, concentrations of elements such as Fe, Al, and As in plantation-dominated sub-basins are raised to ten times higher than in native-dominated sub-basins. In contrast, sub-basins with native forest cover exhibit lower levels of sediment transport and trace element mobilization, suggesting that native vegetation exerts a stabilizing effect that mitigates soil erosion. Despite the substantial differences in sediment transport and element concentrations, Li isotopic data (δ7Li) show minimal fractionation across the different LU/LC types. This indicates that land use changes impact the chemical weathering processes less compared to physical erosion. The isotopic signatures suggest that physical erosion, rather than chemical weathering, is the dominant process influencing trace element distribution in plantation-dominated areas. The study provides critical insights into how forestry practices, specifically the expansion of exotic plantations, accelerate soil degradation and affect the geochemical composition of river systems. The increased sediment loads, and trace element concentrations observed in plantation-dominated sub-basins, raise concerns about the long-term sustainability of forest management practices, particularly regarding their impacts on water quality in urban catchment areas. These results are of significant relevance for environmental management and policy, as they underscore the need for more investigation and sustainable land use strategies to minimize soil erosion and preserve water resources in regions undergoing rapid LU/LC changes.

Youth Engagement in Water Quality Monitoring: Uncovering Ecosystem Benefits and Challenges

A youth-centric participatory mapping approach was employed to monitor the lower Mill Creek, an urban waterway located in Cincinnati, Ohio, by collecting geospatial data points on surface water quality and ecological assets. Utilizing the ArcGIS Field Maps application, a digital survey-based tool was developed to identify key areas related to ecological assets and urban water management challenges. The purpose of this citizen science approach was to allow researchers to capture and understand community perspectives and insights while engaging in scientific research that focuses on identifying geographic vulnerability areas and ecological assets. The primary objective was to empower local community groups and residents in an environmental justice neighborhood to understand the current opportunities and constraints of the adjacent waterbody, enabling informed decision-making for future planning initiatives that benefit both conservation and remediation efforts aligned with local values and needs. A youth-centric participatory mapping approach was employed to monitor the lower Mill Creek, an urban waterway in Cincinnati, Ohio, through the collection of geospatial data on surface water quality and ecological assets. The findings, based on hotspot analysis, revealed significant spatial clustering of heavy debris near the barrier dam and the lower portion of Mill Creek, where it converges with the Ohio River. This accumulation is attributed to the structural features of the barrier dam’s inner flood catchment area, which traps debris during rainfall events. Although no areas showed spatial significance for perceived ecological services, students identified specific areas with esthetic and biodiversity value, particularly at Mill Creek’s confluence with the Ohio River and along the northern stretch of the stream corridor. These findings provide valuable insights for guiding future conservation and remediation efforts that reflect both community values and environmental priorities.

A Localized GIS-Based Multi Decision Criteria Approach in Determining Suitable Sites for Community Toilet Facilities in BASECO Compound, Manila City

Abstract. Access to sanitation remains a major concern in the Philippines due to the increasing population and growing demand for basic needs. This study addresses poor sanitary conditions in slum areas, specifically in BaSECo Compound, Manila, where informal settlers rely on shared toilets. Utilizing GIS and MCDA, the study identifies areas suitable for community toilet facility (CTF) development. The Modified Huff Three-Step Floating Catchment Area (MH3SFCA) method quantified spatial accessibility to existing toilets. The SPAI map shows low accessibility in blocks 15 and New Site, with Gawad Kalinga, Habitat, and Old Site (N) having none. The Analytical Hierarchy Process (AHP) prioritized six criteria, with accessibility being the most significant (33.18%), followed by proximity to water supply (31.76%), communal septic tanks (14.53%), land use (8.2%), flood-prone areas (7.44%), and ground slope (4.89%). The final suitability map identified 14.12% of the 0.6 sq. km. area as highly suitable, including Block 15, Gawad Kalinga, Habitat, and Old Site (N). Ground truth verification visited five candidate sites, which were tested for improved SPAI maps. The inclusion of facilities in Block 15, GK 2, OSN, and H improved accessibility in northern BaSECo. Significant service area improvements for each CTF were observed using Voronoi polygons. This study demonstrates the effectiveness of integrating GIS and MCDA methods for CTF site selection.

Developing a Novel Surgical Care Access Score for Osteoarthritis Patients Considering Total Knee Replacement.

Access to specialized orthopedic care is an important determinant of the decision to undergo total knee replacement (TKR); however, most studies have mainly utilized distance to the nearest high-volume hospital as the primary proxy for access. We applied the two-step floating catchment area (2SFCA) method to develop a more comprehensive TKR access score that accounts for other potential factors, i.e., supply of and demand for this procedure, that also affect access. To apply the 2SFCA method, we first estimated TKR demand using the CDC estimates of prevalence of osteoarthritis, which was multiplied by estimates of patients who would potentially benefit from TKR. We then estimated TKR supply using the number of TKRs performed in each hospital, extracted from the CMS MedPAR database. For the nationwide analysis, we estimated the access score for a radius of 55 km around each census tract in the contiguous US. For a subset of the census tracts, we employed a more realistic but more computationally intensive 42-minute driving distance to determine the robustness of the 55 km assumption, and calculated the Spearman rank correlation between the two access scores. Across the US, the access score was categorized low for 51%, medium for 24%, and high for 25% of census tracts. The Spearman correlation coefficient between these national scores and those with 42-minute driving time was 0.75. We developed a novel TKR care access score that may enhance quality measures available to patients, providers, payors and researchers.

Perception of caregivers on ITNs utilisation and its effectiveness among children under 5years of age in Chikwawa district, Malawi.

In 2020, Malawi had 6.9 million malaria cases and 2551 deaths, mainly in children under five years of age. The 2017-2022 Malawi malaria control strategic plan promoted the consistent use of insecticide-treated nets through free distribution and mass campaigns. Despite widespread availability of the control strategy plan, Chikwawa District continues to suffer from high malaria burden especially among under five children, due to inconsistent insecticide-treated (ITN) net usage. For this reason, this study aimed at exploring caregivers' perceptions on insecticide-treated net utilisation and also find out about its effectiveness among those who consistently use them. This study used a sequential exploratory mixed methods design. The data used for quantitative analysis was drawn from the population of under-five children's caregivers within the catchment area of Chikwawa district hospital. The sample size was 96 participants, as determined by Cochran's formula. The data collection lasted from December 2023 to April 2024 and included four in-depth interviews and three focus group discussions to address the objectives qualitatively. The study revealed that 91.67% of households used ITNs, with 87.50% using them daily. The significant factors influencing ITN utilisation included the number of nets, user satisfaction, perceived impact, user habits, acquisition method, and usage frequency (all p values < 0.001). Under-five malaria cases were also significant (p = 0.025). The odds of the perceived net impact influencing utilisation were 4.956 times greater. Non-usage was due to heat, quality concerns, limited access, breathing difficulties, health conditions such as asthma, and misconceptions about net treatment. The study revealed a strong belief in insecticide-treated net efficacy. However, some challenges such as access, durability, and misinformation of insecticide-treated nets were discovered. These challenges affected utilisation of insecticide-treated nets in agreement with some literature reviewed. The insights found in this study will help policymakers in addressing health interventions for the reduction of malaria cases in Malawi.

‘Par mesure de prudence’. Flood prevention and river regulation in Demer-Dijle confluence area (NE Belgium), 1840s–1880s

Abstract This article analyses the views of experts and political discourse on river regulation, its objectives, and flood prevention in the rural Demer-Dijle catchment areas, the 1840s–1880s – a period marked by climatological extremes and agricultural transition. Via a close read of state archives and parliamentary discussions, we unravel different opinions and interests and find that not all flooding was unwanted. While the Ministry of Public Works, at first, aimed to better regulate water discharge and to improve watercourses for navigational purposes, it later prioritised agricultural interests. However, managing rivers coherently and efficiently was challenging because river powers were dispersed over ministerial departments, provinces, and municipalities that made coordinating upstream and downstream river works difficult. Floods often resulted in the drawing up of new plans, but their implementation often failed to materialise because the government had other worries and insufficient resources available while parliamentarians prioritised the interests of their constituencies.

Exploring the factors influencing the adult population's reluctance to accept the COVID-19 vaccine in Tehran.

While evidence of efficacy, safety, and technical feasibility is crucial when introducing a vaccine, it is equally important to consider the psychological, social, and political factors influencing vaccine acceptance. This study aims to identify the factors contributing to COVID-19 vaccine hesitancy among adults in Tehran, Iran. The study employed a descriptive and analytical cross-sectional design carried out from 2021 to 2022. It involved 260 eligible individuals residing in the catchment areas of Tehran and Shahid Beheshti Universities of Medical Sciences who declined to receive the COVID-19 vaccine, selected through systematic sampling. Data collection was accomplished through a researcher-developed questionnaire and analyzed using SPSS 26 software. The analysis utilized descriptive statistics and non-parametric tests including Mann-Whitney U, Kruskal-Wallis, and Multiple Linear Regression, to examine the relationships between variables. The average scores (SD) across dimensions were as follows: the individual's health status and perceived risk, 15.53 (1.70); contextual and social effects, 17.68 (2.53); awareness, 14.81 (2.34); and beliefs and concerns. 14.91 (2.64), indicating a concerning situation regarding contextual and social impacts and a moderate status as to other areas. The primary reasons for vaccine refusal included fear, lack of belief in the vaccine, concerns about its reliability, illness, and lack of access or time. Acceptance of the vaccine was associated with education, occupation, marital status, number of children at home, and income reduction due to COVID-19. The findings indicate that fear, lack of belief in the vaccine, concerns regarding its reliability, illness, and lack of access or time were the most important factors influencing reluctance to receive the vaccine. Health organizations should consider these factors when encouraging the population to receive the COVID-19 vaccine.