121 research outputs found

    Effect of Activated Carbon Made from Cocoa (Theobroma Cacao L.) Shells on the Adsorption of Iron in Aquifer Water

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    This research aims to determine the effect of activated carbon obtained from cocoa husks (Theobroma cacao L.) on the adsorption of iron (II) present in water of an aquifer for human consumption. Charcoal was prepared at different carbonization temperatures (500, 600 and 700 °C) for 30 minutes and activated with phosphoric acid in the proportions of 1:1. Iron (II) adsorption was determined as a function of variations in mixing speed, contact time, charcoal dosage and stirring speed. It was determined that, over the range considered, agitation speeds had no significant effect on the percentage of iron (II) removal, being the dose of activated carbon and temperature, the most influential variables. The water samples had an initial iron concentration of 3.15 mg/L and 4 mg/L. The best iron (II) adsorption result was obtained with activated carbon at the carbonization temperature of 700 °C, with a mass of 1.5 g of carbon, with efficiencies of 93 % and 98 % for both samples considered. Based on the results, it was concluded water for human consumption is treatable with activated carbon derived from Theobroma cacao L. for the adsorption of iron (II), considering that this parameter is below the maximum limit of 0.3 mg/L allowed by current regulations

    In-vehicle nitrogen dioxide concentrations in road tunnels

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    There is a lack of knowledge regarding in-vehicle concentrations of nitrogen dioxide (NO) during transit through road tunnels in urban environments. Furthermore, previous studies have tended to involve a single vehicle and the range of in-vehicle NO concentrations that vehicle occupants may be exposed to is not well defined. This study describes simultaneous measurements of in-vehicle and outside-vehicle NO concentrations on a route through Sydney, Australia that included several major tunnels, minor tunnels and busy surface roads. Tests were conducted on nine passenger vehicles to assess how vehicle characteristics and ventilation settings affected in-vehicle NO concentrations and the in-vehicle-to-outside vehicle (I/O) concentration ratio. NO was measured directly using a cavity attenuated phase shift (CAPS) technique that gave a high temporal and spatial resolution. In the major tunnels, transit-average in-vehicle NO concentrations were lower than outside-vehicle concentrations for all vehicles with cabin air recirculation either on or off. However, markedly lower I/O ratios were obtained with recirculation on (0.08–0.36), suggesting that vehicle occupants can significantly lower their exposure to NO in tunnels by switching recirculation on. The highest mean I/O ratios for NO were measured in older vehicles (0.35–0.36), which is attributed to older vehicles having higher air exchange rates. The results from this study can be used to inform the design and operation of future road tunnels and modelling of personal exposure to NO

    Water retentivity and environmental impact assessment in the headwaters of the Chambira micro-watershed, San Martin region

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    The study found that maximum precipitation and water retention occur in February for the Cacao sector and in October and February for the Caliza sector, with minimum values in July. The correlation between precipitation and temperature is −0.43 for both sectors, while the negative correlation between retentivity and temperature is stronger in the Caliza sector (−0.467) than in the Cacao sector (−0.096). Precipitation explains 82.07% and 89.92% of the variability in retentivity for the Cacao and Caliza sectors, respectively, according to the R2 coefficients. The environmental impact analysis indicates a medium impact with a value of 5.6

    Removal of Color and Turbidity in Runoff Water using Coconut (Cocos Nucifera) Endocarp Activated Carbon

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    The aim of this research was to determine the efficiency of activated carbon obtained from coconut (Cocos nucifera) endocarp in the reduction of color in runoff water to improve its quality. For this purpose, activated carbon was produced at a carbonization temperature of 700 °C in a time of 30 minutes and phosphoric acid at a concentration of 85% was used as an activating agent. A completely randomized design was used, consisting of 3 treatments (100, 50 and 25 g of activated carbon) and a control (without treatment), with three replicates of each treatment, where 1 L of water from the uptake was filtered. It was determined that the best percentage removal was obtained with treatment 3 (T3) in the reduction of color and turbidity with average values of 97.56% and 97.11%, respectively. An activated carbon filter was installed in the San Lorenzo - Moyobamba sector in a similar way to the laboratory tests, in which the efficiency of this product in reducing the color and turbidity of the water was demonstrated, achieving values suitable for human consumption

    USE OF MORINGA SEED (Moringa oleifera Lam.) AS A BIOCOAGULANT TO IMPROVE SURFACE WATER QUALITY

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    Using Moringa oleifera (Moringa oleifera Lam.) seed as a biocoagulant to enhance surface water's physical and chemical quality was the goal of this study. The methodology applied for the generation of experimental data was through the use of the Jar Test equipment, in a dose of 40 mg/L to 140 mg/L, then a fast mixing of 100 rpm for 1 minute and a slow mixing of 40 rpm for 10 minutes was performed, and sedimentation was left for 5 to 30 minutes, with 5 minutes intervals between each dose. The results show that an optimal biocoagulant dose of 100 mg/L at 20 minutes produced a turbidity reduction effectiveness of 97.06%. Hardness fell by 12% of its starting value, conductivity and total dissolved solids increased dramatically, and there was a 92.3% reduction in perceived colour, which showed that the use of Moringa seeds as a coagulant had a favourable effect on reducing the concentration of turbidity and colour. Because of this, Moringa (Moringa oleifera Lam.) can be used as a natural source to purify drinking water. The Tukey HSD test applied to the turbidity removal percentages, indicates that the means are not significantly different. However, the experimental evaluation indicates that after 20 minutes, the best results are obtained

    Evaluación de los residuos sólidos generados en el distrito de Barranca en un entorno de Covid-19

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    El objetivo de la investigación es evaluar los residuos sólidos generados en el distrito de Barranca en un entorno de Covid-19. La metodología se basa en la investigación descriptiva, por lo que se evaluó con instrumentos de evaluación de segregación en la fuente y toma de datos a través de cuestionarios sobre las preferencias en el consumo y su compromiso con el reciclaje en la población de Barranca. Para esta evaluación se tomó una muestra de 50 casas, la cual fue obtenida mediante la fórmula del Dr. Kunitoshi. Obtenidos los datos, se procesaron con estadísticas básicas, en donde se determinó los principales productos consumidos durante la pandemia, correspondiendo los valores más altos al mes de junio, con 60 % en alimentos y 24 % en medicamentos. En cuanto al porcentaje de habitantes que reciclan se obtuvo un valor de 6 %, mientras que mayor es el porcentaje de la población que no recicla con un valor máximo de 88 %. El cuanto a la producción per cápita, sobresalió el Jirón Arequipa con 0.568 kg/hab./día con relación a los demás. También el mes de junio sobresalió en la cantidad de residuos segregados con 1623.15 kg/mes para la muestra de 50 casas. Por lo tanto, se concluye que hubo un incremento de residuos domiciliarios durante la pandemia, influenciado por el incremento en el consumo de artículos de primera necesidad, por el consumo de medicamentos y también de equipos de protección para prevenir los contagios de Covid-19

    Silence Is Not Golden: Invisible Latinas Living with HIV in the Midwest

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    This qualitative study was conducted to better understand the health needs and concerns of immigrant HIV-infected Latinas residing in the Midwest United States. Individual interviews (n = 18) were conducted in Spanish with Latinas in Kansas, Oklahoma and Missouri. Women were at different stages of acceptance about their HIV diagnosis and four common themes emerged from the data: pregnancy as a death sentence, HIV is taboo, God as their only resource, and living in isolation. Silence was an over-arching theme present throughout all the narratives and many women had never shared their stories about HIV with anyone. Depressive symptoms and suicidal ideation were common. These findings have implications for strategies to address the HIV prevention and HIV-related healthcare needs of this population of women. Results from this study further suggest that efforts are needed to break the silence surrounding HIV and to reduce HIV-related stigma in smaller Midwestern Hispanic communities

    Concurrent Assessment of Phthalates/HEXAMOLL® DINCH Exposure and Wechsler Intelligence Scale for Children Performance in Three European Cohorts of the HBM4EU Aligned Studies

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    Information about the effects of phthalates and non-phthalate substitute cyclohexane-1,2-dicarboxylic acid diisononyl ester (HEXAMOLL® DINCH) on children's neurodevelopment is limited. The aim of the present research is to evaluate the association between phthalate/HEXAMOLL® DINCH exposure and child neurodevelopment in three European cohorts involved in HBM4EU Aligned Studies. Participating subjects were school-aged children belonging to the Northern Adriatic cohort II (NAC-II), Italy, Odense Child Cohort (OCC), Denmark, and PCB cohort, Slovakia. In each cohort, children's neurodevelopment was assessed through the Full-Scale Intelligence Quotient score (FSIQ) of the Wechsler Intelligence Scale of Children test using three different editions. The children's urine samples, collected for one point in time concurrently with the neurodevelopmental evaluation, were analyzed for several phthalates/HEXAMOLL® DINCH biomarkers. The relation between phthalates/HEXAMOLL® DINCH and FSIQ was explored by applying separate multiple linear regressions in each cohort. The means and standard deviations of FSIQ were 109 ± 11 (NAC-II), 98 ± 12 (OCC), and 81 ± 15 (PCB cohort). In NAC-II, direct associations between FSIQ and DEHP's biomarkers were found: 5OH-MEHP+5oxo-MEHP (β = 2.56; 95% CI 0.58-4.55; N = 270), 5OH-MEHP+5cx-MEPP (β = 2.48; 95% CI 0.47-4.49; N = 270) and 5OH-MEHP (β = 2.58; 95% CI 0.65-4.51; N = 270). On the contrary, in the OCC the relation between DEHP's biomarkers and FSIQ tended to be inverse but imprecise (p-value ≥ 0.10). No associations were found in the PCB cohort. FSIQ was not associated with HEXAMOLL® DINCH in any cohort. In conclusion, these results do not provide evidence of an association between concurrent phthalate/DINCHHEXAMOLLR DINCH exposure and IQ in children.This work received external funding from the European Union’s Horizon 2020 research and innovation program under grant agreement No. 733032 [“European Human Biomonitoring Initiative” (HBM4EU)] and received co-funding from the author’s organizations. NAC-II: This research was funded by: the European Union through its Sixth Framework Program for RTD (contract “PHIME” No. FOOD-CT-2006-016253); the Institute for Maternal and Child Health IRCCS “Burlo Garofolo”, Trieste, Italy (RC 12/12 funded by Ministry of Health—Italy); CROME LIFE Project “Cross-Mediterranean Environment and Health Network” (LIFE12 ENV/GR/001040). OCC: The cohort was funded by the Odense University Hospital, Denmark; the Region of Southern Denmark, The Municipality of Odense, Denmark; The University of Southern Denmark; the Mental Health Service of the Region of Southern Denmark; Odense Patient data Exploratory Network (OPEN), Den mark; The Danish Center for Hormone Disrupting Chemicals (MST-611-00012); The Danish Research Council (4004-00352B_FSS); Novo Nordisk Foundation, Denmark (grant no. NNF19OC0058266 and NNF17OC0029404); Sygeforsikring Danmark (journalnr. 2021-0173); The Collaborative foundation between Odense University Hospital and Rigshospitalet, Helsefonden, Beckettfonden, the Danish Mental Health Fund, Health Insurance Denmark. The LS-MS/MS equipment was financially supported by the Velux Foundation. PCB: PCB cohort was funded by the Slovak Research and Development Agency, project no. APVV-0571-12 and the Ministry of Health of the Slovak Republic, project no. 2014/47-SZU-11. The APC was funded by the European Union’s Horizon 2020 research and innovation program under grant agreement No. 733032.S
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