Synthesis of biochar from chili seeds and its application to remove ibuprofen from water. Equilibrium and 3D modeling.

In this work chili seeds (Capsicum annuum) were used as raw material in the synthesis of biochar at temperatures between 400 and 600 °C. The samples were chemically, texturally and morphologically characterized and their properties were correlated with the calcination temperature. The adsorption mechanism of IBP was elucidated by analyzing the effect of solution pH, ionic strength and temperature, whereas that, the intraparticle diffusion mechanism was clarified through the application of a 3D diffusional model. The results evidenced that raising the pyrolysis temperature promotes a greater content of disordered graphitic carbon (51.6-85.02%) with small surface area (0.52-0.18 m2/g) and low quantity of functional groups. The adsorption study demonstrated that the biochar synthesized at 600 °C (C600) enhances the adsorption capacity >50 folds compared with chili seeds. Moreover, at pH = 7 the adsorption mechanism is governed by π-acceptor and attractive electrostatic interactions, whereas at basic pH the main adsorption mechanism is π-acceptor. Additionally, hydrophobic interactions become important by increasing the presence of NaCl. The application of 3D diffusional model based on surface diffusion interpreted clearly the kinetic curves obtaining values of Ds ranging from 2.31 × 10-8-2.51 × 10-8 cm2 s-1. Besides, it was determined that intraparticle mass flux is larger along the shortest axis of the seed, and always directed toward the particle center. The maximum mass flux takes place in the center of particle, and it advances like a moving front as time was increased.

Active compounds and distinctive sensory features provided by American ginseng (Panax quinquefolius L.) extract in a new functional milk beverage.

American ginseng (Panax quinquefolius L.) has recognized neurocognitive effects, and a ginsenoside-rich extract of the root of the plant has been shown to improve cognitive functions in young adults. This study aimed at assessing the chemical and sensory profiles of a UHT-treated, low-lactose functional milk containing American ginseng. Individual ginsenosides in the milk were analyzed by HPLC. Descriptive sensory analysis was performed by a trained panel to quantitatively document sensory changes resulting from the addition of ginseng and the UHT process on flavored and unflavored milks. Consumer acceptance of the product was also investigated. Total ginsenoside content in the UHT-treated milk enriched with the ginseng extract after UHT process treatment was 7.52 mg/100 g of milk, corresponding to a recovery of 67.6% compared with the content in the unprocessed extract. The intake of 150 to 300 mL of this ginseng-enriched milk provides the amount of total ginsenosides (11.5 to 23 mg) necessary to improve cognitive function after its consumption. Both the presence of ginsenosides and their thermal treatment affected some sensory properties of the milk, most notably an increase in bitterness and metallic taste, the appearance of a brownish color, and a decrease in milky flavor. Levels of brown color, bitterness, and metallic taste were highest in the industrially processed ginseng-enriched milk. The bitterness attributable to ginseng extract was reduced by addition of vanilla flavor and sucralose. A consumer exploratory study revealed that a niche of consumers exists who are willing to consume this type of product.

Wastewater use in agriculture: irrigation of sugar cane with effluents from the Cañaveralejo wastewater treatment plant in Cali, Colombia.

In Valle del Cauca, south-west Colombia, surface and ground waters are used for sugar cane irrigation at a rate of 100 m3 of water per tonne of sugar produced. In addition large quantities of artificial fertilizers and pesticides are used to grow the crop. Preliminary experiments were undertaken to determine the feasibility of using effluents from the Cañaveralejo primary wastewater treatment plant in Cali. Sugar cane variety CC 8592 was planted in 18 box plots, each 0.5 m2. Six were irrigated with conventional primary effluent, six with chemically enhanced primary effluent and six with groundwater. For each set of six box plots, three contained local soil and three a 50:50 mixture of sand and rice husks. The three irrigation waters were monitored for 12 months, and immediately after harvest the sugar content of the sugar cane juice determined. All physico-chemical quality parameters for the three irrigation waters were lower than the FAO guideline values for irrigation water quality; on the basis of their sodium absorption ratios and electrical conductivity values, both wastewater effluents were in the USDA low-to-medium risk category C2S1. There was no difference in the sugar content of the cane juice irrigated with the three waters. However, the microbiological quality (E. coli and helminth numbers) of the two effluents did not meet the WHO guidelines and therefore additional human exposure control measures are required in order to minimize any resulting adverse health risks to those working in the wastewater-irrigated fields.

Prevalence of bacteriophages infecting Staphylococcus aureus in dairy samples and their potential as biocontrol agents.

The prevalence of bacteriophages infecting Staphylococcus aureus in dairy samples was assessed. Fourteen Staph. aureus strains were used in enrichment cultures of 75 dairy samples. All samples grew specific Staph. aureus bacteriophages. According to the host range, 8 different phages were isolated. Three of them, phages PhiH5, PhiG7, and PhiA72, were found in 89% of the samples; all the isolated phages were temperate. Phages PhiH5 and PhiA72 were used in preliminary bacterial challenge tests against Staph. aureus in milk. A phage mixture (1:1) was more effective than each single phage, most likely by preventing the survival of lysogenized cells. Phages inhibited Staph. aureus in UHT and pasteurized whole-fat milk. However, the phages were less active in semi-skimmed raw milk and little inhibition was achieved in whole, raw milk. Killing of Staph. aureus was observed at room temperature and at 37 degrees C, but not at refrigeration temperature.

Eficacia del uso de bisoprolol con hidroclorotiazida en la reducción de la masa del ventrículo izquierdo en pacientes con hipertensión arterial en comparación con el uso del enalapril / Effectiveness of the bisoprolol use with hydroclorothiazida in the reduction of the mass of the left ventricle in patients with arterial hypertension in comparison with the use of the enalapril

La hipertension arterial (HTA) es un factor de riesgo para enfermedad cardiovascular y es considerada como un problema de salud pública. La HTA constituye una sobrecarga de presión, que induce en el corazón una serie de modificaciones anatómicas y funcionales para compensar esta sobrecarga y esto se logra a través de la hipertrofia del ventrículo izquierdo (HVI). La HVI constituye un factor de riesgo independiente para mortalidad cardiovascular en pacientes con HTA; por consiguiente, la utilización de diferentes fármacos antihipertensivos, pueden reducir y/o revertir la HVI. Evaluar la eficacia de la combinación de bisoprolol con hidroclorotiazida en la reducción de la presión arterial (PA) y masa del ventrículo izquierdo (MVI), en pacientes con HTA y compararlo con el uso de un IECA. El presente estudio clínico controlado y doble ciego, evaluó la regresión de la HVI, en 19 pacientes hipertensos asignados al azar en dos: grupo A (n=10) recibió la combinación de bisoprolol con hidroclorotiazida y el grupo B (n=9) recibió enalapril, durante 6 meses, 16 pacientes completaron el estudio. Se observó reducción significativa de la MVI al 3er y 6to mes de tratamiento en los pacientes tratados con la combinación de bisoprolol con hidroclorotiazida (p<0,05). La reducción de la HVI en los pacientes tratados enalapril ocurrió al 6to mes y no fue significativo (p>0,05). Ambos medicamentos redujeron la PA (p<0,05) 7 pero esta fue mayor en el grupo A (bisoprolol con hidroclorotiazida). La combinación de bisoprolol con hidroclorotiazida es más efectiva en la reducción de la PA y MVI en pacientes con HTA estadio I y II que el enalapril

¿Cómo conseguir éxito en un simposio de medicina? experiencia con el simposio: resurgimiento de las enfermedades tropicales / Symposium of medicine in with success setting? symposium with experience: reappearance of tropical disease

Durante la conmemoración del 76 aniversario de la fundación de la Cátedra de Medicina Tropical de la Universidad Central de Venezuela se planificó y efectuó el Simposio: Resurgimiento de las Enfermedades Tropicales en Venezuela, considerando exitoso por sus asistentes, organizadores y participantes, que motivó la elaboración de éste artículo, el cual tiene como propósito: describir, evaluar y narrar el procedimiento metodológoco empleado para su realización. Se nombró un Comité Organizador, la elaboración de un programa viable, la invitación de profesionales especialiastas en los temas seleccionados, el ofrecimiento del simposio a los posibles patrocinantes y la contratación de una compañia experta en eventos de esta naturaleza, con siete (7) meses de antelación. Se pregunto sobre la manera de como se enteraron del simposio y sobre preferencias temáticas para las próximas jornada. Asistieron 301 personas: 42 por ciento estudiantes de medicina, 22 por ciento médicos y 21 por ciento bioanalistas. El financiamiento lo aportaron cinco (5) laboratorios de la industria farmacéutica (75 por ciento), la inscripción de los asistentes, la Facultad de Medicina de la Universidad Central y la Dirección de extensión de la misma Universidad. El 90 por ciento de los que respondieron señaló que se enteraron del simposio, mediante un afiche publicitario, y tuberculosis, dengue y toxoplasmosis fueron los temas preferidos para el futuro. La participación de estudiantes universitarios, médicos y bioanalistas sugiere hacia quienes debe dirigirse la publicidad en futuras jornadas. El financiamiento de la industria farmacéutica es fundamental en actividades de esta naturaleza, ya que sin su concurso es más difícil, aunque no imposible su realización

Feasibility of waste stabilization pond technology for small municipalities in Colombia.

The selection of any wastewater treatment technology should take into consideration both "software" and "hardware" aspects. There are contrasting opinions regarding the feasibility of waste stabilisation ponds (WSP): some emphasise their advantages while others are concerned with their high land area requirements. As with any technology, WSP are feasible under specific circumstances related to the context where they are to be implemented. In this study data were collected from three regions in Colombia (Nariño, Tolima and Valle del Cauca) in order to assess the feasibility of WSP under real conditions in a tropical country. A feasibility matrix was developed in order to organise and synthesise the information gathered. The results obtained showed that WSP are highly feasible in Tolima and Valle del Cauca due to the fact that these regions have geographical, socio-economic and technical characteristics that enhance the advantages of WSP technology. Nariño has a very mountainous topography along with other local limitations that hinder the application of WSP technology. The cost of land was not found to be a real limitation for the technology, whereas the availability of land is. Finally, the feasibility matrix may be a good planning tool at regional or national levels in order to help decision-making regarding cost-effective wastewater treatment alternatives on the basis of local conditions.

Microbiological quality of a waste stabilization pond effluent used for restricted irrigation in Valle Del Cauca, Colombia.

This paper discusses the applicability of effluent reuse in agriculture after treatment in a series of anaerobic, facultative and maturation ponds. The WSP system is located in Ginebra municipality, a small town in southwest Colombia. The total HRT is 12 days. Several samples of the final effluent were taken over a 55 day period and were analysed for E. coli, Streptococcus spp. and helminth eggs. Some additional grab samples were taken to determine the presence of pathogenic bacteria such as Salmonella spp. and Shigella spp. The results showed that the system was able to remove 4 log units of E. coli, 1 log unit of Streptococcus spp. and 100% of helminth eggs. Meanwhile, Salmonella spp. were detected in the effluent of the facultative pond whilst Shigella spp. were not detected in any sample. The main species of helminth eggs encountered were Taenia spp., Ascaris spp., Trichuris spp., Hymenolepis nana, H. diminuta and Enterobius vermicularis. Removal efficiencies were satisfactory despite the relatively short HRT. Nevertheless, WHO guidelines were slightly surpassed in the case of E. coli for unrestricted irrigation. The helminth egg value was always below the maximum WHO limit. Hence, this effluent can be safely used for restricted irrigation provided that field workers are protected from direct contact with wastewater given the presence of Salmonella spp. in the facultative pond effluent.

¿Qué significa medicina basada en evidencia? / What it means medicine evidence-based?

El presente artículo revisa críticamente el significado de la medicina basada en evidencia. El estudio comienza definiendo el concepto de paradigma de acuerdo a Thomas Khun y dentro de este contexto por qué la medicina basada en evidencia constituye un cambio de paradigma. Después de evaluar las dos principales perspectivas discrepantes del paradigma arriba señalado resuelve la controversia mediante el análisis etimiológico de la palabra evidencia y la fenomenología del conocimiento para luego concluir con una posición propia de los autores

Fiebre prolongada: una visión contemporánea de un viejo problema clínico de difícil diagnóstico / Prolongue fever: a contemporary vision and old clinical problem to diagnosis difficult

El objetivo de este estudio es determinar las causas más frecuentes de Síndrome Febril Prolongado (SFP) en el HUC y diseñar estrategias de aproximación diagnóstica al paciente con SFP en nuestro medio. Se presenta un estudio prospectivo realizado en los servicios Medicina Interna y Enfermedades Infecciosas del Adulto de HUC, entre diciembre de 1993 y diciembre de 1995, obteniéndose 100 pacientes que cumplieron los siguientes criterios de inclusión: 1) Edad> 12 años; 2) Fiebre >38,3ºC y 3) Fiebre >21-días de duración. Se llenó un formato de extracción de datos que incluyó: 1) identificación, 2) antecedentes epidemiológicos, 3) síntomas constitucionales, 4) examen físico, 5) estudios complementarios (laboratorio, imagenología y citomorfológicos). Los resultados se analizaron según métodos estadísticos descriptivos. De los pacientes, 58 correspodieron al sexo masculino y 42 al sexo femenino. La edad promedio fue de 36.9 años con rango entre 13 y 80, procedentes en su mayoría de Caracas (51 por ciento) y Estado Miranda (22 por ciento). Las patologías se presentaron en el siguiente orden: Infecciosas 55 por ciento, neoplásicas 18 por ciento, enfermedades del tejido conectivo 14 por ciento, misceláneas 6 por ciento, sin diagnóstico 7 por ciento. El S.I.D.A. se presenta como la patología más frecuente (24 por ciento) lo que implica un cambio en el abordaje del paciente con SFP, siendo prioritario determinar la presencia del Virus de Inmunodeficiencia Humana (HIV), para clasificar a los pacientes en seronegativos que serán estudiados según esquemas clásicos, y seropositivos donde deberán buscarse principalmente causas infecciosas. En ambos grupos deberán investigarse las patologías infecciosas propias de nuestro medio