Abstract:Analysis of 45 years of precipitation data from 28 meteorological stations in the Central Valley of Costa Rica revealed significant ENSO-related variability. El Nino events were associated with 15-30% reduction in wet season rainfall, while La Nina years showed 10-20% increases. Climate projections suggest intensification of ENSO impacts by mid-century, with implications for water resource management and agricultural planning in Costa Ricas most densely populated region.
Abstract:Novel hydrogels were developed from soybean protein isolate crosslinked with genipin, a natural crosslinking agent. Mechanical testing showed tunable elastic moduli (5-50 kPa) suitable for soft tissue applications. In vitro studies with human fibroblasts demonstrated excellent biocompatibility with cell viability above 95% after 7 days. The biodegradable hydrogels showed controlled degradation rates over 4-8 weeks, making them promising candidates for wound healing and cartilage repair applications.
Abstract:Autonomous recording units were deployed across 15 Atlantic Forest fragments of varying sizes (5-500 ha) in Sao Paulo state to assess avian diversity through acoustic monitoring. Analysis of 8,640 hours of recordings identified 187 bird species, with fragment size positively correlated with species richness. Large-bodied frugivores and insectivores showed highest sensitivity to fragmentation, highlighting the importance of maintaining connectivity between forest remnants for conservation.
Abstract:Silver nanoparticles were synthesized using aqueous leaf extract of Azadirachta indica (neem) as a reducing and stabilizing agent. Characterization by UV-Vis spectroscopy, TEM, and XRD confirmed formation of crystalline AgNPs with average size of 25-40 nm. The biosynthesized nanoparticles demonstrated potent antibacterial activity against both gram-positive and gram-negative bacteria, with MIC values of 6.25-12.5 ug/mL against multidrug-resistant clinical isolates.
Abstract:This research evaluated the seismic performance of four base-isolated public hospitals in the Valparaiso and OHiggins regions following the 2010 Maule earthquake. Instrumented response data and numerical simulations were used to assess isolation system effectiveness. Results demonstrated that base-isolated structures experienced 75% lower floor accelerations and maintained full operational capacity compared to conventionally designed facilities, validating seismic isolation as an essential strategy for critical infrastructure in high-seismicity zones.
Abstract:This study assessed wind energy resources in Turkana County using three years of meteorological data from 12 measurement stations. Mean wind speeds ranged from 4.8 to 8.2 m/s at 50m hub height, with annual energy production estimates of 2,400-4,100 kWh/m2. Economic analysis showed that small-scale wind turbines (10-50 kW) could provide electricity at costs competitive with diesel generators, offering a viable pathway for rural electrification in northern Kenya.
Abstract:A network of 48 IoT-enabled water quality monitoring stations was deployed across the Magdalena River basin to enable real-time assessment of physicochemical parameters. The solar-powered sensor nodes measured pH, dissolved oxygen, turbidity, conductivity, and temperature at 15-minute intervals. Data analysis over 18 months identified seasonal pollution patterns and enabled early warning alerts for industrial discharge events, improving response times for environmental authorities by 85%.
Abstract:This study developed and validated a convolutional neural network model for automated diabetic retinopathy screening using fundus images from Malaysian diabetic patients. Training on 45,000 annotated images from six public hospitals, the model achieved 94.2% sensitivity and 91.8% specificity in detecting referable diabetic retinopathy. Implementation in primary care clinics reduced specialist referral waiting times by 67%, demonstrating the potential for AI-assisted screening in resource-limited settings.
Abstract:The mining industry accounts for significant greenhouse gas emissions, with copper production in Chile contributing substantially to national carbon footprints. This study evaluates the technical and economic feasibility of transitioning large-scale copper mining operations to solar-hydrogen energy systems. We conducted detailed assessments at three major mining sites in the Atacama Desert, analyzing solar irradiance data, energy consumption patterns, and operational requirements. Our proposed hybrid system combines 500 MW photovoltaic installations with green hydrogen production and storage facilities capable of providing 24/7 power supply. Technical simulations demonstrate that the system can meet 92% of mining energy demands, including haul truck electrification and mineral processing. Economic modeling reveals levelized cost of energy (LCOE) of $0.038/kWh, competitive with current diesel-based operations. The transition would reduce annual CO2 emissions by 1.2 million tonnes per site. Implementation roadmaps, regulatory considerations, and workforce transition strategies are presented. Sensitivity analysis confirms project viability under various commodity price and policy scenarios.
Abstract:The COVID-19 pandemic exacerbated pre-existing mental health disparities across Latin America, disproportionately affecting vulnerable populations. This mixed-methods study examines social determinants of mental health in post-pandemic contexts across Argentina, Brazil, Colombia, and Mexico. Quantitative data from 8,500 survey respondents were complemented by 240 in-depth interviews with individuals from marginalized communities including informal workers, indigenous populations, migrants, and LGBTQ+ individuals. Results reveal that economic precarity (OR=3.2), housing instability (OR=2.8), and limited healthcare access (OR=2.5) significantly predict depression and anxiety disorders. Qualitative findings highlight the compounding effects of social stigma, discrimination, and inadequate social protection systems. Notably, community-based support networks emerged as protective factors, reducing mental health symptom severity by 35% among participants with strong social connections. Based on these findings, we propose an integrated policy framework addressing structural determinants while strengthening community mental health services. Pilot implementation in two municipalities demonstrated 28% improvement in mental health outcomes over 18 months.