Vol 5 No 1 (2024)

This study investigates the structural and adsorption properties of modified and unmodified Cucurbita moschata seed husk with a view to evaluating its potential as a low-cost bio-sorbent for crude oil clean-up.  The raw seed husk was subjected to chemical modification through acetylation, aiming to enhance its surface characteristics and functional group availability. Comprehensive characterizations were conducted using Fourier Transform Infrared Spectroscopy (FTIR), Scanning Electron Microscopy (SEM) and surface area analysis to determine changes in morphology and functional groups. Batch adsorption experiments were carried out to assess the sorption efficiency of both modified and unmodified Cucurbita moschata seed husk in removing crude oil from aqueous solutions under varying conditions of contact time, catalyst usage. Adsorption kinetics and isotherm models, including first-order, pseudo-second-order, Intra diffusion, Freundlich, Langmuir and Temkin were applied to interpret the experimental data. The results revealed that acetylation significantly improved the surface roughness, porosity and active binding sites of the sample, leading to enhanced oil uptake capacity. The modified Cucurbita moschata seed husk exhibited superior adsorption efficiency, with equilibrium data fitting well to the Freundlich isotherm and Pseudo-second order kinetic model, indicating multilayer adsorption on a heterogeneous surface. These findings suggest that modified Cucurbita moschata seed husk, holds promising potential as a sustainable, ecofriendly, and effective adsorbent for treating oil spill clean-up in our environment

This study examines the correlation between particulate matter (PM2.5 and PM10) concentrations in the city of Antananarivo and precipitation over the constantly burning open landfill (Andralanitra), located 12 km from the city. Statistical analysis was conducted using daily PM2.5 and PM10 concentration data from air quality monitoring stations (November 2023 to October 2024) and daily precipitation data from the Andralanitra landfill. The results indicate a weak negative correlation between the daily concentrations of PM2.5 and PM10 and the daily precipitation levels. The correlation is stronger for PM10 than for PM2.5, likely due to the differences in particle size: PM10 particles are more affected by precipitation. Additionally, monthly precipitation levels at Andralanitra show a moderate negative correlation with the monthly concentrations of PM2.5 and PM10. Seasonal variations also influence the overall concentrations of PM, and an increase in precipitation intensity at Andralanitra leads to a reduction in the number of days considered polluted. These findings emphasize that air pollution caused by particulate matter (PM2.5 and PM10) is directly influenced by precipitation levels at Andralanitra.

Introduction: Cholera is endemo-epidemic in Bukavu. The aim of the study was to assess the environmental determinants of permanent contamination of spring and well water and to evaluate some of the chemical factors responsible for the persistence of Vibrio cholerae in water consumed by cholera patients.
Methods: Conducted in the Bukavu health district from September 2020 to September 2021, this was a cross-sectional. The potential of hydrogen (pH) of the water was evaluated before comparing it with the survival of Vibrio cholerae. A total of 641 latrines, 92 water sources, and wells were surveyed, with 298 samples analyzed in the laboratory.
Results: Out of the 641 latrines surveyed, 367 (57%) were found to be unsanitary; 54 (59%) of the water sources and wells were also deemed unsanitary. In total, 57% of the water samples were found to contain Vibrio cholerae, with 90% exhibiting an alkaline pH, of which 54% tested positive for the bacteria. Conversely, 10% of the samples had an acidic pH, with 80% of those containing Vibrio cholerae. The pH levels of the water remained alkaline both during the epidemic (95%) and post-epidemic (84%), thereby favoring the survival of Vibrio cholerae serotypes Ogawa and Inaba in these water sources. An acidic pH was observed to increase the likelihood of Vibrio cholerae survival in these waters by a factor of 3.39.
Conclusion: Spring and well water are consistently contaminated with Vibrio cholerae due to the unsanitary conditions of nearby latrines. The presence of Vibrio cholerae serotypes Inaba and Ogawa in these water sources is further influenced by the alkaline and acidic pH levels.

This study focuses on thermal comfort in  some classroom school buildings of the Malagasy Ministry of National Education, located in the city of Diego-Suarez, characterized by a warm tropical climate throughout the year. This study was  carried out in December 2023, then between January and February 2024. The analysis is based on the adaptive approach, using questionnaires and taking measurements of thermal parameters via weather sensor. During study hours from 7:30 a.m. to 11:30 a.m. in the morning and 2:30 p.m. to 5:30 p.m. in the afternoon, the questionnaires are completed at the same time as in-situ measurements are taken. In total, 223 questionnaires were completed by the occupants including (students and teachers), distributed in four classrooms of two different primary schools. The results reveal that the percentage of thermal acceptance inside the old school reaches 35%, compared to only 15% for the modern school. The majority of respondents believe that the air flow speed is more favorable in the old building, with a perception of comfort at 60%, compared to 40% for the modern building.

Discussion of the relationship of infectious disease and biodiversity loss most commonly is framed in terms of the impact of diminishing biodiversity on zoonotic diseases among humans. Less examined is the role of infectious disease as a direct driver of biodiversity loss through species declines, local extirpations, and global extinctions. Recent studies, however, suggest that infectious diseases in wildlife populations are emerging at notably high rates. The diversity of emerging infectious diseases, magnified by the likelihood that there will be an increased frequency of outbreaks over time, have raised concern that infectious disease may play a strong role in wildlife species extinctions. The purpose of this Commentary is to draw attention to the growing role infectious pathogens are having in wild animal biodiversity loss and ecosystem disruption, changes which, in turn, rebound on human health and wellbeing.