A set of experiments was carried out for validating a 40 cm long and ½ inch diameter sulphonation... more A set of experiments was carried out for validating a 40 cm long and ½ inch diameter sulphonation falling film reactor for the sulphonation of hydrogenated palm stearine-derived dodecylbenzene (DDB) and methyl esters (ME) compared to oleumderived gaseous SO3. Volumetric titration was used for determining the percentages of sulphonated (active) matter, sulphuric acid content and unsulphonated oil by petroleum ether extraction. The reactor's functionality was tested in the conditions reported by Gutiérrez et al., for DDB sulphonation. The falling film reactor analysis techniques applied to sulphonated DDB in the scale bank reactor were thus validated in Universidad Nacional de Colombia's Chemical Engineering Department Laboratory with the involvement of the Química Básica Colombiana Company (LIQ, Caloto, Cauca, Colombia). The influence of different process variables on the sulphonation of a mixture of methyl esters was then evaluated. The results obtained in the sulphonator we...
Electrons sourced from low carbon energy sources can be used as a green reagent to enable hydrome... more Electrons sourced from low carbon energy sources can be used as a green reagent to enable hydrometallurgical recycling of lithium-ion batteries (LIB), significantly reducing the chemical consumption and carbon footprint of the recycling process. In this talk we will describe electrochemical driven alternatives for metals extraction and separation developed within the critical materials institute (CMI) for the recycling of end-of-life LIBs. The discussion will focus on how these technologies can be incorporated in the battery recycling flowsheet, and the impact of the electrochemical processes in the economic and carbon footprint of battery recycling
Introducción: La capacidad de conducir un vehículo motorizado impacta en la participación comunit... more Introducción: La capacidad de conducir un vehículo motorizado impacta en la participación comunitaria de una persona con lesión medular congénita o adquirida. Al respecto, los simuladores de conducción sirven tanto de en frenamiento como para determinar la idoneidad para conducir un vehículo motorizado. Objetivo: Describir la experiencia de uso de un simulador de conducción adaptado en entorno de realidad virtual en personas con lesión medular tipo paraplejia de origen congénito o adquirido. Método: Se seleccionaron 6 usuarios/as con paraplejia congénita o adquirida, entre 18 y 24 años de edad, sin antecedentes de patología visual, con resistencia máxima y sensibilidad completa en miembros superiores. Todos recibieron 8 sesiones de 40 minutos de uso del simulador. Se aplicó evaluación basal, al primero y tercer mes post intervención sobre estado funcional, impacto psicosocial de la asistencia tecnológica (PIADS) y satisfacción usuaria. Resultados: En PIADS, el puntaje para Adaptab...
Journal of infection and chemotherapy : official journal of the Japan Society of Chemotherapy, 2005
In clinical Helicobacter pylori isolates, metronidazole resistance has been associated with mutat... more In clinical Helicobacter pylori isolates, metronidazole resistance has been associated with mutations in the rdxA and frxA genes. The aim of this study was to examine the role of the rdxA and frxA genes after the in vitro induction of metronidazole resistance. A total of five suscep-tible H. pylori isolates were initially exposed to different subinhibitory metronidazole concentrations to induce in vitro resistance to metronidazole. Susceptible and resistant strains after the in vitro induction of resistance were examined to evaluate mutations of the rdxA and frxA genes by sequence analysis. After the in vitro induction of resistance, analysis revealed that two and four susceptible strains developed resistance when cultured with 0.3 microg/ml and 0.6 microg/ml of metronidazole, respectively. Before and after the induction of resistance, none of the susceptible strains that developed low and moderate levels of resistance presented any mutation in either of the evaluated genes, whereas...
Background. Primary and acquired resistance to the antimicrobial agents is a primary reason for t... more Background. Primary and acquired resistance to the antimicrobial agents is a primary reason for the failure of Helicobacter pylori eradication therapies. We assessed the primary antibiotic resistance rates of H. pylori to three different antibiotics and its relationship due to the annual antibiotic consumption in Japan during the period prior to approval of anti‐H. pylori therapy in Japan.Materials and Methods. Antibiotic susceptibility was tested using the agar dilution method for clarithromycin, amoxicillin and metronidazole. Isolates were considered resistant when the MIC value was > 8 mg/l for metronidazole, > 1 mg/l for clarithromycin and < 0.5 mg/l for amoxicillin.Results. Helicobacter pylori isolates were obtained from 593 Japanese patients from 1995 to 2000. Primary resistance of H. pylori to clarithromycin, metronidazole and amoxicillin was found in 11%, 9% and 0.3% strains, respectively. The proportion with clarithromycin resistance significantly increased from 7%...
JAMA: The Journal of the American Medical Association, 1963
The authors have recently encountered at the Hospital Dos de Mayo, Lima, Peru, 5 cases of thalliu... more The authors have recently encountered at the Hospital Dos de Mayo, Lima, Peru, 5 cases of thallium intoxication within a period of approximately one and a half years. In 1 instance a dense abdominal shadow corresponding to the liver was discovered by chance on roentgenograms obtained in an examination of the lumbosacral spine because of complaints of discomfort in that area. In this article, the clinical and experimental findings of the condition will be described, with stress laid on the roentgen features. Case Report G. J. O., a 22-year-old male, was brought by his family, against his will, to the hospital on Nov. 16, 1961, with a 16-day history of anorexia, epigastric pain, vomiting, myalgias, arthralgias, paresthesias, and hyperesthesias, principally in the arms and legs, but also in the lower back. The physical findings were considered unreliable because of the patient's lack of co-operation. He was moderately dehydrated and in no acute distress. There were muscular pains, especially when the arms an...
A set of experiments was carried out for validating a 40 cm long and ½ inch diameter sulphonation... more A set of experiments was carried out for validating a 40 cm long and ½ inch diameter sulphonation falling film reactor for the sulphonation of hydrogenated palm stearine-derived dodecylbenzene (DDB) and methyl esters (ME) compared to oleumderived gaseous SO3. Volumetric titration was used for determining the percentages of sulphonated (active) matter, sulphuric acid content and unsulphonated oil by petroleum ether extraction. The reactor's functionality was tested in the conditions reported by Gutiérrez et al., for DDB sulphonation. The falling film reactor analysis techniques applied to sulphonated DDB in the scale bank reactor were thus validated in Universidad Nacional de Colombia's Chemical Engineering Department Laboratory with the involvement of the Química Básica Colombiana Company (LIQ, Caloto, Cauca, Colombia). The influence of different process variables on the sulphonation of a mixture of methyl esters was then evaluated. The results obtained in the sulphonator we...
Electrons sourced from low carbon energy sources can be used as a green reagent to enable hydrome... more Electrons sourced from low carbon energy sources can be used as a green reagent to enable hydrometallurgical recycling of lithium-ion batteries (LIB), significantly reducing the chemical consumption and carbon footprint of the recycling process. In this talk we will describe electrochemical driven alternatives for metals extraction and separation developed within the critical materials institute (CMI) for the recycling of end-of-life LIBs. The discussion will focus on how these technologies can be incorporated in the battery recycling flowsheet, and the impact of the electrochemical processes in the economic and carbon footprint of battery recycling
Introducción: La capacidad de conducir un vehículo motorizado impacta en la participación comunit... more Introducción: La capacidad de conducir un vehículo motorizado impacta en la participación comunitaria de una persona con lesión medular congénita o adquirida. Al respecto, los simuladores de conducción sirven tanto de en frenamiento como para determinar la idoneidad para conducir un vehículo motorizado. Objetivo: Describir la experiencia de uso de un simulador de conducción adaptado en entorno de realidad virtual en personas con lesión medular tipo paraplejia de origen congénito o adquirido. Método: Se seleccionaron 6 usuarios/as con paraplejia congénita o adquirida, entre 18 y 24 años de edad, sin antecedentes de patología visual, con resistencia máxima y sensibilidad completa en miembros superiores. Todos recibieron 8 sesiones de 40 minutos de uso del simulador. Se aplicó evaluación basal, al primero y tercer mes post intervención sobre estado funcional, impacto psicosocial de la asistencia tecnológica (PIADS) y satisfacción usuaria. Resultados: En PIADS, el puntaje para Adaptab...
Journal of infection and chemotherapy : official journal of the Japan Society of Chemotherapy, 2005
In clinical Helicobacter pylori isolates, metronidazole resistance has been associated with mutat... more In clinical Helicobacter pylori isolates, metronidazole resistance has been associated with mutations in the rdxA and frxA genes. The aim of this study was to examine the role of the rdxA and frxA genes after the in vitro induction of metronidazole resistance. A total of five suscep-tible H. pylori isolates were initially exposed to different subinhibitory metronidazole concentrations to induce in vitro resistance to metronidazole. Susceptible and resistant strains after the in vitro induction of resistance were examined to evaluate mutations of the rdxA and frxA genes by sequence analysis. After the in vitro induction of resistance, analysis revealed that two and four susceptible strains developed resistance when cultured with 0.3 microg/ml and 0.6 microg/ml of metronidazole, respectively. Before and after the induction of resistance, none of the susceptible strains that developed low and moderate levels of resistance presented any mutation in either of the evaluated genes, whereas...
Background. Primary and acquired resistance to the antimicrobial agents is a primary reason for t... more Background. Primary and acquired resistance to the antimicrobial agents is a primary reason for the failure of Helicobacter pylori eradication therapies. We assessed the primary antibiotic resistance rates of H. pylori to three different antibiotics and its relationship due to the annual antibiotic consumption in Japan during the period prior to approval of anti‐H. pylori therapy in Japan.Materials and Methods. Antibiotic susceptibility was tested using the agar dilution method for clarithromycin, amoxicillin and metronidazole. Isolates were considered resistant when the MIC value was > 8 mg/l for metronidazole, > 1 mg/l for clarithromycin and < 0.5 mg/l for amoxicillin.Results. Helicobacter pylori isolates were obtained from 593 Japanese patients from 1995 to 2000. Primary resistance of H. pylori to clarithromycin, metronidazole and amoxicillin was found in 11%, 9% and 0.3% strains, respectively. The proportion with clarithromycin resistance significantly increased from 7%...
JAMA: The Journal of the American Medical Association, 1963
The authors have recently encountered at the Hospital Dos de Mayo, Lima, Peru, 5 cases of thalliu... more The authors have recently encountered at the Hospital Dos de Mayo, Lima, Peru, 5 cases of thallium intoxication within a period of approximately one and a half years. In 1 instance a dense abdominal shadow corresponding to the liver was discovered by chance on roentgenograms obtained in an examination of the lumbosacral spine because of complaints of discomfort in that area. In this article, the clinical and experimental findings of the condition will be described, with stress laid on the roentgen features. Case Report G. J. O., a 22-year-old male, was brought by his family, against his will, to the hospital on Nov. 16, 1961, with a 16-day history of anorexia, epigastric pain, vomiting, myalgias, arthralgias, paresthesias, and hyperesthesias, principally in the arms and legs, but also in the lower back. The physical findings were considered unreliable because of the patient's lack of co-operation. He was moderately dehydrated and in no acute distress. There were muscular pains, especially when the arms an...
Uploads
Papers by LUIS HERNANDO BUITRAGO ALDANA