Browsing by Author "Bermejo Zari, Daniel Leonardo"

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Biosorción de Cd (II) y Pb (II) en columna de lecho fijo con cáscara de cacao
(2018) Vera Cabezas, Luisa Mayra; Bermejo Zari, Daniel Leonardo; Uguña Rosas, María Fernanda; García Alvear, Nancy Beatriz; Flores Zamora, Marittza Eleanor; Brazales Quizhpe, Diana Esperanza
In this work the results of the biosorption of Pb(II) and Cd (II) of synthetic waters with cocoa shell in fixed bed columns are presented. The experimental data were fitted to several models describing the breakdown curve for single component and two component systems. The removal percentages of lead and cadmium in single-component systems are 91% and 90%, respectively. In bicomponent systems Pb-Cd the percentage of lead removal 88% and cadmium 90%. The Dose-Response model in two-component and single-component systems was the one that best reproduced the experimental rupture curves throughout the measured range.
Comparative adsorption of ciprofloxacin on sugarcane bagasse from Ecuador and on commercial powdered activated carbon
(2021) Peñafiel Tenorio, María Eulalia; Matesanz, José María; Vanegas Peña, María Eulalia; Bermejo Zari, Daniel Leonardo; Mosteo Abad, Rosa; Ormad, María P.
This work examined the adsorption capacity of sugarcane bagasse (SB) for the removal of ciprofloxacin (CPX) from water using batch experiments and a fixed bed column and compared its adsorption performance with a powdered activated commercial carbon (PAC). Both adsorbents achieved a similar percentage removal of about 78% with doses of 3 g L−1 of SB and 0.3 g L−1 of PAC (20 mg L−1 initial CPX concentration at 30 °C). The maximum removal was obtained at a pH between 6 and 8. SB adsorption isotherms were fitted to the Langmuir, BET and Freundlich models showing a maximum adsorption capacity of 13.6 mg g−1. The kinetic data for both SB and PAC fitted the pseudo second-order model (R2 = 0.99). The adsorption process was faster on the SB (65% of elimination in the first 5 min) than on the PAC. The study of the adsorbent properties shows that SB is a macroporous solid with a specific surface area 250 times smaller than PAC. The thermodynamic results show that SB adsorption was physical and exothermic. The main suggested interactions between CPX and SB are elec- trostatic attraction, hydrogen bonding and dipole-dipole interactions. The experiments carried out in a fixed bed show that the adsorption capacity at breakthrough increases with the bed height. The adsorption capacity at sat- uration time was 9.47 mg g−1 at a flow rate of 3 mL min−1, a bed height of 14 cm, and a diameter of 1.5 cm. The experimental data were fitted to the Bohart-Adams model (R2 = 0.98). These results highlight the capacity of sugarcane bagasse to adsorb ciprofloxacin from water, illustrating its potential as a low-cost adsorbent.
Corrigendum: “Comparative adsorption of ciprofloxacin on sugarcane bagasse from Ecuador and on commercial powdered activated carbon” (Science of the Total Environment (2021) 750, (S0048969720350270), (10.1016/j.scitotenv.2020.141498))
(2022) Matesanz Martín, José María; Bermejo Zari, Daniel Leonardo; Vanegas Peña, María Eulalia; Peñafiel Tenorio, María Eulalia; Ormad, María P.; Mosteo Abad, Rosa
The authors regret that the printed version of the above article contained a number of errors. The correct and final version follows. The authors would like to apologise for any inconvenience caused.
Resistencia bacteriana en pacientes hospitalizados con infecciones de vías urinarias del Hospital Vicente Corral Moscoso. Enero – diciembre, 2018
(2019-10-23) Bermejo Zari, Daniel Leonardo; Flores Chulli, Edith Paulina; Baculima Tenesaca, José Mauricio
Background: 50% of antimicrobials (ATM) are used inappropriately for what researchers, scientific societies and health authorities have placed on epidemiological alert for the current antibiotic inefficiency and the daily struggle towards the manufacture of new antibiotics that allow facing new forms of resistance. In Ecuador, epidemiological surveillance of bacterial resistance is measured by the NIPHR (National Institute for Public Health Research), which allows to generate alerts against epidemiological outbreaks (1)(2). General objective: To determine bacterial resistance in hospitalized patients with urinary tract infection of the Vicente Corral Moscoso hospital, during the period January to December 2018. Methodology: A retrospective and descriptive observational study was performed; the universe was constituted by 261 reports of positive urine cultures, of which 154 were sensitive and 107 presented some type of resistance. For the analysis and tabulation of results were used the 2010 Excel program and the statistical program IBM SPSS V25 test version, the analysis was descriptive statistics. Results: In 2018 there was a 41.0% prevalence of urinary tract infections with bacterial resistance. The mainly isolated bacteria were: E. Coli 48.6% producing ESBL, K. Pneumoniae 20.6% producing carbapenemases and E. cloacae 12.1% producing AmpC-type betalactamases, with women being sex with mostly affected and finally the areas with the highest number of cases were: clinic, pediatrics, surgery and neonatology. Conclusions: E. coli, K. pneumonia and E. cloacae were the main uropathogens with resistance of 2018, including BLEE, carbapenemases and beta-lactamase of AmpC type.