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Spodumene flotation stands as the most commonly used method to concentrate lithium minerals. However, it faces significant challenges related to low collector recoveries and similarity in the surface characteristics of the minerals, which make the effective separation of this valuable mineral difficult. For this reason, numerous researchers have conducted studies to address and confront this problem. In this work, an exhaustive bibliographic search was carried out using keywords and search queries, and the results were structured in three sections according to temporal, methodological, and thematic criteria. The first section covers the period from 1950 to 2004, focusing on experimental tests. The second section covers from 2004 to the present and focuses on flotation tests and measurement analysis. Simultaneously, the third section spans from 2011 to the present and is based on molecular dynamics simulations. Topics covered include spodumene surface properties, the influence of metal ions, pre-treatment techniques, and the use of collectors. Ultimately, molecular dynamics simulations are positioned as a tool that accurately represents experimental phenomena. In this context, specialized software such as Materials Studio or Gromacs prove to be reliable instruments that allow a detailed study of mineral surfaces and other elements to be carried out, which justifies their consideration for future research in this scientific field.

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INTRODUCTION: Infectious keratitis of fungal origin mainly affects people in tropical and subtropical countries, and is an important cause of preventable blindness. Topical antifungals, particularly natamycin and voriconazole, are considered effective, but it is not clear which one is the best treatment alternative. METHODS: We searched in Epistemonikos, the largest database of systematic reviews in health, which is maintained by screening multiple information sources, including MEDLINE, EMBASE, Cochrane, among others. We extracted data from the systematic reviews, reanalyzed data of primary studies, conducted a meta-analysis and generated a summary of findings table using the GRADE approach. RESULTS AND CONCLUSIONS: We identified three systematic reviews including three studies overall,all of which were randomized trials. We concluded natamycin probably is associated with better visual acuity after infection, and it prevents corneal perforation and/or need to perform therapeutic keratoplasty compared to voriconazole in fungal keratitis.

INTRODUCCIÓN: La queratitis infecciosa de origen fúngico afecta principalmente a personas de países tropicales y subtropicales, y constituye una importante causa de ceguera prevenible. Los antifúngicos tópicos, en particular la natamicina y el voriconazol, se consideran efectivos, pero no está claro cuál de ellos constituye la mejor alternativa de tratamiento. MÉTODOS: Realizamos una búsqueda en Epistemonikos, la mayor base de datos de revisiones sistemáticas en salud, la cual es mantenida mediante el cribado de múltiples fuentes de información, incluyendo MEDLINE, EMBASE, Cochrane, entre otras. Extrajimos los datos desde las revisiones identificadas, analizamos los datos de los estudios primarios, realizamos un metanálisis y preparamos una tabla de resumen de los resultados utilizando el método GRADE. RESULTADOS Y CONCLUSIONES: Identificamos tres revisiones sistemáticas que en conjunto incluyeron tres estudios primarios, todos correspondientes a ensayos aleatorizados. Concluimos que natamicina probablemente se asocia a mejor agudeza visual tras la infección, y que previene la perforación corneal y/o la necesidad de realizar queratoplastia terapéutica en comparación a voriconazol en queratitis fúngica.

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INTRODUCTION: Rhegmatogenous retinal detachment is caused by a tear in the retina and is a frequent cause of vision loss. Its treatment is mainly surgical and the following alternatives can be identified: scleral buckling or classic surgery, pneumatic retinopexy and vitrectomy. Between the first two options, most professionals prefer scleral buckling over pneumatic retinopexy, but the latter is a simpler, cheaper and lower-risk procedure, so it is still considered as an option for selected patients. However, there is little evidence comparing both interventions. METHODS: To answer this question we used Epistemonikos, the largest database of systematic reviews in health, which is maintained by screening multiple information sources, including MEDLINE, EMBASE, Cochrane, among others. We extracted data from the systematic reviews, reanalyzed data of primary studies, conducted a meta-analysis and generated a summary of findings table using the GRADE approach. RESULTS AND CONCLUSIONS: We identified three systematic reviews including six studies overall, of which three were randomized trials. We concluded the anatomic result might be better with scleral buckling in terms of retinal reattachment and risk of recurrence, but the risk of ocular adverse events might be lower with pneumatic retinopexy.

INTRODUCCIÓN: El desprendimiento de retina de tipo regmatógeno es aquel causado por un desgarro o ruptura de la retina, y es causa frecuente de pérdida de visión. Dentro del manejo quirúrgico existen varias opciones, entre ellas el implante de silicona o cirugía convencional y la retinopexia neumática. A pesar de que la mayoría de los profesionales prefiere el uso de implante de silicona, la retinopexia neumática es un procedimiento más simple, de menor costo y sigue siendo considerada como alternativa en algunos casos de desprendimiento de retina regmatógeno, sin embargo hay poca evidencia que compare ambas intervenciones. MÉTODOS: Para responder esta pregunta utilizamos Epistemonikos, la mayor base de datos de revisiones sistemáticas en salud, la cual es mantenida mediante búsquedas en múltiples fuentes de información, incluyendo MEDLINE, EMBASE, Cochrane, entre otras. Extrajimos los datos desde las revisiones identificadas, reanalizamos los datos de los estudios primarios, realizamos un metanálisis y preparamos una tabla de resumen de los resultados utilizando el método GRADE. RESULTADOS Y CONCLUSIONES: Identificamos tres revisiones sistemáticas que en conjunto incluyeron seis estudios primarios, de los cuales tres corresponden a ensayos aleatorizados. Concluimos que el resultado anatómico podría ser mejor con el uso de implante de silicona en términos de re-aplicación de la retina y del riesgo de recurrencia del desprendimiento, pero la retinopexia neumática podría disminuir la incidencia de efectos adversos quirúrgicos oculares.

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