ABSTRACT
In the global race to produce green hydrogen, wastewater-to-H2 is a sustainable alternative that remains unexploited. Efficient technologies for wastewater-to-H2 are still in their developmental stages, and urgent process intensification is required. In our study, a mechanistic model was developed to characterize hydrogen production in an AnMBR treating high-strength wastewater (COD > 1000 mg/L). Two aspects differentiate our model from existing literature: First, the model input is a multi-substrate wastewater that includes fractions of proteins, carbohydrates, and lipids. Second, the model integrates the ADM1 model with physical/biochemical processes that affect membrane performance (e.g., membrane fouling). The model includes mass balances of 27 variables in a transient state, where metabolites, extracellular polymeric substances, soluble microbial products, and surface membrane density were included. Model results showed the hydrogen production rate was higher when treating amino acids and sugar-rich influents, which is strongly related to higher EPS generation during the digestion of these metabolites. The highest H2 production rate for amino acid-rich influents was 6.1 LH2/L-d; for sugar-rich influents was 5.9 LH2/L-d; and for lipid-rich influents was 0.7 LH2/L-d. Modeled membrane fouling and backwashing cycles showed extreme behaviors for amino- and fatty-acid-rich substrates. Our model helps to identify operational constraints for H2 production in AnMBRs, providing a valuable tool for the design of fermentative/anaerobic MBR systems toward energy recovery.
ABSTRACT
Objetivo: Determinar la efectividad de 5-Fluorouracilo intralesional en el alivio sintomático, astigmatismo y deseo de cirugía en pacientes con pterigión primario. Métodos: Estudio experimental realizado entre enero y marzo de 2020 en la Unidad de Oftalmología del Hospital del Salvador, Chile. Se seleccionaron 14 ojos (14 pacientes) en lista de espera quirúrgica, expuestos a inyecciones intralesionales quincenales de 10 mg de 5-FU. Se realizó una evaluación clínica inicial con OSDI para medición sintomática, cámara fotográfica y lámpara de hendidura para apariencia clínica, y autorrefractómetro para astigmatismo, siendo reevaluados 60 días después, añadiéndose la pregunta de si mantenían el deseo de operarse. Se dividió la muestra en grupo A y B según recibieron dos o una dosis de 5-FU, respectivamente. Resultados: La edad promedio de los participantes fue 56,8 ± 11,1 años. El grupo A presentó un OSDI inicial de 50 ± 23,8 que, posterior a la intervención, se redujo a 21 ± 13,5 (p < 0,001). El grupo B tuvo un OSDI inicial de 47 ± 17,3, disminuyendo a 22 ± 16,2 (p < 0,005). Ambos cambios estadísticamente significativos. En cuanto al aspecto físico, hubo reducción del tamaño lesional en 2 de los 14 pacientes, ambos del grupo A. No hubo cambios respecto al grado de astigmatismo. Hubo 2 pacientes que decidieron no realizarse la cirugía posterior a la intervención. Conclusión: La inyección intralesional de 5-FU demostró mejoría significativa en el alivio sintomático, sin complicaciones asociadas, generando un tratamiento alternativo al quirúrgico en pacientes con pterigión primario, pudiendo posponer la cirugía.
Objectives: To determine the effectiveness of intralesional 5-Fluorouracil (5-FU) in symptomatic relief, astigmatism, and desire for surgery in patients with primary pterygium. Methods: The experimental study was carried out between January and March 2020 in the Ophthalmology Unit of the Hospital del Salvador, Chile. Fourteen eyes (14 patients) were selected on the surgical waiting list and exposed to fortnightly intralesional injections of 10 mg of 5-FU. An initial evaluation was performed with OSDI for symptomatic measurement, a photographic camera and slit lamp for clinical appearance, and an auto-refractometer for astigmatism, being re-evaluated 60 days later, adding the question of whether they maintained the desire to undergo surgery. The sample was divided into groups A and B depending on whether they received two or one dose of 5-FU, respectively. Results: The average age of the participants was 56.8 ± 11.1 years. Group A presented an initial OSDI of 50 ± 23.8, which, after the intervention, decreased to 21 ± 13.5 (p < 0.001). Group B had an initial OSDI of 47 ± 17.3, decreasing to 22 ± 16.2 (p < 0.005)-statistically significant changes. The degree of astigmatism had no changes. Regarding the physical aspect, there was a reduction in the size of the lesion in 2 of the 14 patients, both in group A. Two patients decided not to undergo surgery after the intervention. Conclusions: The intralesional injection of 5-FU showed a significant improvement in symptomatic relief without associated complications, generating a therapeutic alternative in patients with primary pterygium without surgical indication.
ABSTRACT
OBJECTIVES: To determine the effectiveness of intralesional 5-Fluorouracil (5-FU) in symptomatic relief, astigmatism, and desire for surgery in patients with primary pterygium. METHODS: The experimental study was carried out between January and March 2020 in the Ophthalmology Unit of the Hospital del Salvador, Chile. Fourteen eyes (14 patients) were selected on the surgical waiting list and exposed to fortnightly intralesional injections of 10 mg of 5-FU. An initial evaluation was performed with OSDI for symptomatic measurement, a photographic camera and slit lamp for clinical appearance, and an auto-refractometer for astigmatism, being re-evaluated 60 days later, adding the question of whether they maintained the desire to undergo surgery. The sample was divided into groups A and B depending on whether they received two or one dose of 5-FU, respectively. RESULTS: The average age of the participants was 56.8 ± 11.1 years. Group A presented an initial OSDI of 50 ± 23.8, which, after the intervention, decreased to 21 ± 13.5 (p < 0.001). Group B had an initial OSDI of 47 ± 17.3, decreasing to 22 ± 16.2 (p < 0.005)-statistically significant changes. The degree of astigmatism had no changes. Regarding the physical aspect, there was a reduction in the size of the lesion in 2 of the 14 patients, both in group A. Two patients decided not to undergo surgery after the intervention. CONCLUSIONS: The intralesional injection of 5-FU showed a significant improvement in symptomatic relief without associated complications, generating a therapeutic alternative in patients with primary pterygium without surgical indication.
