Obtención, caracterización y actividad fotocatalítica del óxido de titanio dopado con nitrógeno a partir de urea y nitrato de amonio para su utilización en la región del visible del espectro electromagnético

En el presente trabajo de investigación se sintetizaron óxidos de titanio a partir de urea y nitrato de amonio como precursores del nitrógeno dopante. Los materiales sintetizados se caracterizaron mediante difracción de rayos X (DRX), espectroscopia infrarroja con transformada de Fourier (FT-IR), espectroscopia fotoelectrónica de rayos X (XPS) y espectroscopia ultravioleta-visible de reflectancia difusa (DRS). La actividad fotocatalítica de los mismos se evaluó en la degradación del naranja de metilo. Mediante el método empleado se logró dopar la estructura del óxido de titanio (rutilo y Degussa P25) con nitrógeno, obteniéndose una única fase cristalina. Además, se determinó la fuente dopante más limpia (nitrato de amonio) y la proporción de nitrógeno (0,2) ideal para realizar el dopaje. El óxido de titanio (Degussa P25) dopado con nitrato de amonio con proporción de 0,2 degradó el azo-colorante al 14,55% en 200 minutos de reacción. Las condiciones de operación utilizadas fueron: concentración de 6 mg/L del colorante, pH de la solución igual a 2,5 y concentración de fotocatalizador de 70 mg/100mL.In the present investigation titanium oxides were synthesized from urea and ammonium nitrate as nitrogen dopant precursors. The synthesized materials were characterized by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), X-ray photoelectron spectroscopy (XPS) and ultraviolet-visible diffuse reflectance spectroscopy (DRS). The photocatalytic activity of the samples was measured by the degradation of the methyl orange. By the method it was possible to dope the structure of titanium oxide (rutile and Degussa P25) with nitrogen to obtain a single crystalline phase. Furthermore, the dopant source cleaner (ammonium nitrate) and the proportion of nitrogen (0,2) ideal for doping were determined. Titanium oxide (Degussa P25) doped with ammonium nitrate ratio of 0,2 degraded the azo-dye to 14,55% in 200 minutes of reaction. The operating conditions used were: concentration of 6 mg/L of dye solution at pH equal to 2,5 and concentration of 70 mg/100mL photocatalyst

Energy consumption in plastic industry - review of studies developed

El nivel de consumo energético para la producción de artículos plásticos es una variable que en los últimos años ha cobrado gran importancia, ya que tiene no solo un impacto ambiental en su uso racional sino que tiene un costo representativo para la producción. El artículo contiene una breve justificación de la relevancia de cuantificar el consumo de energía requerido para la producción de piezas plásticas, como también la forma de medirlo en variables tales como consumos fijos y variables, así como determinar el consumo de energía específico por planta de procesamiento, proceso y por equipos. Posteriormente, se hace un recuento de diferentes estudios de consumo y uso eficiente de la energía más relevantes en la industria del plástico, a nivel regional, nacional e internacional. El presente artículo es logrado con el objetivo de proveer un material de referencia básico a investigadores interesados en este tema.The level of energy consumption for the production of plastics is a variable that in recent years has gained great importance due to its environmental impact on energy rational use, and its representative cost for production. This paper contains a brief explanation of the importance of quantifying the energy consumption required for the production of plastic parts, as well as how to measure variables such as consumption fixed and variable, and determine the specific energy consumption for processing plants, for processes and equipment. Subsequently, it describes several studies about energy consumption rates relevant to the plastics industry in Colombia and different countries that count large polymer processing plants. This paper is made in order to provide a basic reference material to researchers interested in this topic

Relaciones entre proyecto de vida y organizaciones: una mirada metafórica desde la planeación, la formación y la contabilidad

It is important that companies carry out proper planning and training in order to have favorable financial results. Thus, the objective was to analyze the relationships between planning, business formation and accounting process in financial results, using the human life project as a metaphor for organizations. Interviews were conducted with seven businessmen from organizations in the municipality of Andes (Antioquia), located in four groups called entrepreneurship, in growth, sustainability and consolidated.Finally, it was concluded that there is the proposed metaphor of organization with its relation to the life project of the human being, starting from relating the planning and training processes to obtain positive financial resultsEs importante que las empresas realicen una debida planeación y formación con el propósito de tener resultados financieros favorables. Así, se planteó como objetivo analizar las relaciones entre la planeación, la formación de las empresas y el proceso contable en los resultados financieros, utilizando el proyecto de vida del ser humano como metáfora para las organizaciones. Se realizaron entrevistas a siete empresarios de organizaciones del municipio de Andes (Antioquia) ubicadas en cuatro grupos denominados emprendimiento, crecimiento, sostenibilidad y consolidación.Finalmente se concluyó que sí existe la metáfora propuesta de organización en relación con el proyecto de vida del ser humano, partiendo de relacionar los procesos de planeación y formación para la obtención de resultados financieros positivos

Diagnosis and Treatment of Autoimmune Hepatitis

RESUMEN: La hepatitis autoinmune (HAI) es una enfermedad crónica, progresiva, más frecuente en mujeres y de etiología desconocida, caracterizada histológicamente por infiltrado de células mononucleares en el tracto portal y bioquímicamente por hipertransaminasemia e hipergamaglobulinemia y por la presencia de autoanticuerpos específicos para el hígado. La respuesta al tratamiento inmunosupresor es generalmente buena y la resolución tanto bioquímica como histológica de la inflamación se logra en el 87% de los pacientes en tres años después de haber iniciado dicho tratamiento. Diversos estudios han demostrado que, en ausencia de tratamiento, la enfermedad lleva rápidamente a fibrosis y la tasa de mortalidad es mayor del 80% a los cinco años del diagnóstico. Por el contrario, si el paciente ya presenta cirrosis hepática el tratamiento disminuye la respuesta inflamatoria y la progresión histológica de la fibrosis. La expectativa de vida de los pacientes que responden al tratamiento excede el 90% a los 10 años y es de 80% a los 20 años; sin embargo, 10-15% no tienen respuesta adecuada o satisfactoria al tratamiento médico. En este artículo se revisan el tratamiento estándar y las nuevas opciones para el manejo de esta enfermedad.ABSTRACT: Autoimmune hepatitis is a chronic, progressive disease, more frequent in women than in men, and of unknown etiology. Histologically, it is characterized by mononuclear cell infiltration in the portal tract, and biochemically by elevation of transaminases, hypergammaglobulinemia, and the presence of liver specific autoantibodies. Response to immunosuppressive treatment is generally good and the resolution of inflammation, both biochemically and histologically, is achieved in 87% of patients in 3 years after immunosuppressive treatment is started. Several studies have shown that in the absence of treatment the disease progresses rapidly to fibrosis, and the mortality rate is higher than 80% in the 5 years following diagnosis in untreated patients. Nevertheless, even if the patient has liver fibrosis, treatment decreases the inflammatory response and the histological progression of fibrosis. Life expectancy of patients who respond to treatment exceeds 90% at 10 years, and is 80% at 20 years; however, 10-15% of patients do not have satisfactory response to medical treatment. Standard treatment and new therapeutic options are reviewed in this article

Comparative study of alumina and carbon black as reinforcing fllers in natural rubber mixtures

The formulation of compounds of rubbers is the art and science of selecting and combining rubber and additives in order to produce a compound with the chemical, physical and mechanical properties required in the fnished product and to make possible easier processing conditions. Rubber formulations generally involve different compounds, each one with a specifc function, and therefore they have an impact on the properties and processing costs of the fnal product. These compounds can be classifed in the following categories: polymers (natural or synthetic rubber), vulcanization system (vulcanizing agents, accelerator, activator or inhibitor), fllers (reinforcing or not reinforcing), antidegradant (antioxidant, antiozonant), lubricants and extenders, pigments and other special additives. In this work, the addition of carbon black and alumina (Al2O3) as reinforcing fllers in natural rubber, was investigated. Rheological, mechanical and morphological properties were evaluated by using a vulcanization reometer, a Shore A durometer, a Universal Testing Machine and optical microscopy techniques. The results showed that both fllers had an effect mainly on tensile strength, hardness and viscosity. The article aims to contribute to the rubber industry once they require knowing the effects generated by the participation of black fllers and white fller for natural rubber compositesLa formulación de compuestos de caucho, es el arte y la ciencia de seleccionar y combinar cauchos y aditivos para producir un compuesto con las propiedades químicas, físicas y mecánicas necesarias en el producto terminado, así como para facilitar el procesamiento. Esta formulación generalmente contiene diferentes compuestos que tienen una función específca, y por lo tanto, con un impacto en las propiedades, procesabilidad y costos del producto fnal. Estos componentes pueden clasifcarse en varias categorías: polímeros (caucho natural y sintético), sistemas de vulcanización (agentes de vulcanización, acelerador, activador o inhibidor), carga (reforzante, no reforzante), antidegradantes (antioxidante, antiozonante), lubricantes y extendedores, pigmentos de color y otros aditivos especiales. En la presente investigación se estudiaron los efectos generados por la adición de negro de humo y alúmina (Al2O3) como cargas reforzantes de un caucho natural. Se realizaron ensayos de dureza, tensión, dispersión morfológica, reometría de vulcanización, microscopia óptica y reometría de torque, para determinar las propiedades de las mezclas. Fue posible determinar que tanto el negro de humo como la carga blanca de alúmina infuyen principalmente en propiedades físico mecánicas de la mezcla como viscosidad, dureza y resistencia a la tensión. Estos resultados contribuyen a posibles aplicaciones en nuevos desarrollos y productos en caucho natural al utilizar cargas blancas reforzantes. &nbsp

Redefinición, correlación e implicaciones geotectónicas del batolito de Ibagué, Colombia

New fieldwork, petrographic, geochemical, and zircon U-Pb geochronologic data allow us to identify new units and redefine the limits of the Ibagué batholith. The Ibagué batholith, located to the north of the Ibagué Fault, was divided into two geological units: the Anzoátegui Metatonalite (~194.7 km2) and Ibagué Tonalite (~278 km2). To the south of the Ibagué fault, the name Ibagué batholith is maintained, but its original extension changes to ~3200 km2 due to theoccurrence of the Carboniferous Belalcázar and Los Guayabos gabbros, the Permian Ortega and La Plata granites, and the early Jurassic Páez quartz-monzodiorite. The Anzoátegui Metatonalite and Ibagué Tonalite are composed of calc-alkaline and metaluminous metatonalites, tonalites, and granodiorites, yielding U-Pb crystallization ages between 158.2+1.2/–0.4 and 150.17±0.86 Ma, and between 145.71+0.72/–1.42 Ma and 138.48±0.95 Ma, respectively. The Ibagué batholith is constituted by calc-alkaline to high K calc-alkaline, metaluminous and peraluminous, tonalites, granodiorites, and monzogranites, yielding crystallization ages between 171.5±1.3 and 137.9±1.0 Ma. The Ibagué batholith, the Anzoátegui Metatonalite, and the Ibagué Tonalite are calcic granitoids generated in an arc environment, presenting Nb, Ti, and P negative anomalies. The geotectonic position, petrographic and geochemical composition, and crystallization ages allowed us to correlate the Ibagué batholith, the Anzoátegui Metatonalite, and the Ibagué Tonalite with the Segovia and Los Alisales batholiths, the Siapana granodiorite, the Payandé stock, and volcanic units such as the La Malena volcanic rocks, the Segovia and Chaparral vulcanites. This correlation also drives the separation of the Ibagué batolith from other units like the Carboniferous, Permian, and Early to Middle Jurassic plutons cropping out further east.Nuevos datos de campo, petrografía, geoquímica y geocronología U-Pb en circón permiten redefinir el batolito de Ibagué y proponer nuevas unidades. El batolito de Ibagué, al norte de la Falla de Ibagué, ha sido dividido en la Metatonalita de Anzoátegui (∼194,7 km2) y la Tonalita de Ibagué (∼278 km2). Al sur de la falla de Ibagué conserva el nombre de batolito de Ibagué con una extensión de ~3200 km2, debido a la escisión de los gabros de Belalcázar y Los Guayabos de edad Carbonífera, los granitos de Ortega y La Plata de edad Pérmica, y la Cuarzomonzodiorita de Páez de edad Jurásico temprano. La Metatonalita de Anzoátegui y la Tonalita de Ibagué se componen de metatonalitas, tonalitas y granodioritas calco-alcalinas metaluminosas, con edades U-Pb para la Metatonalita de Anzoátegui entre 158,2+1,2/–0,4 y 150,17±0,86 Ma y para la Tonalita de Ibagué entre 145,71+0,72/–1,42 Ma y 138,48±0,95 Ma, Jurásico medio a Cretácico inferior. El batolito de Ibagué está constituido por tonalitas, granodioritas y monzogranitos calco-alcalinos a calco-alcalinos de alto K, metaluminosos y peraluminosos, con edades entre 171,5±1,3 y 137,9±1,0 Ma. El batolito de Ibagué, la Metatonalita de Anzoátegui y la Tonalita de Ibagué son granitoides cálcicos de arco, con anomalías negativas de Nb, Ti y P. La posición geotectónica, la composición petrográfica y química, y las edades de cristalización permitieron correlacionar el batolito de Ibagué, La Metatonalita de Anzoátegui y la Tonalita de Ibagué con los batolitos de Segovia y Los Alisales, la Granodiorita de Siapana, el stock de Payandé, y con unidades volcánicas como el Volcánico de La Malena, las Vulcanitas de Segovia y Chaparral. Con esta correlación se separan unidades que estaban asociadas al batolito de Ibagué que afloran en una posición más oriental, definidas como los cinturones de plutones del carbonífero, Pérmico y Jurásico temprano a medio

Technological Development of CNC Machine Tool for Machining Soft Materials

In recent years, the process carried out in the GACIPE research group is related to the development of the base technology of the manufacturing and metalworking industry. The machine tools that are vital for the consolidation and competitiveness of the industry in any country has been approached through two approaches: The design and construction of the new machine. In this aspect, the modeling of the structure and the displacements’ parameterization allows defining the precision of the movements and the rational use of energy. The adaptation and repowering of a used machine. In this approach, the recovery and technological updating proposed to recover its performance, becoming an excellent alternative to improving and perfecting the production of a company. In both cases, the CNC milling machine tools are controlled by free software. The application proposed is mechanized in soft materials

Population structure among Mycobacterium tuberculosis Isolates from pulmonary tuberculosis patients in Colombia

Background: Phylogeographic composition of M. tuberculosis populations reveals associations between lineages and human populations that might have implications for the development of strategies to control the disease. In Latin America, lineage 4 or the Euro-American, is predominant with considerable variations among and within countries. In Colombia, although few studies from specific localities have revealed differences in M. tuberculosis populations, there are still areas of the country where this information is lacking, as is a comparison of Colombian isolates with those from the rest of the world. Principal Findings: A total of 414 M. tuberculosis isolates from adult pulmonary tuberculosis cases from three Colombian states were studied. Isolates were genotyped using IS6110-restriction fragment length polymorphism (RFLP), spoligotyping, and 24-locus Mycobacterial interspersed repetitive units variable number tandem repeats (MIRU-VNTRs). SIT42 (LAM9) and SIT62 (H1) represented 53.3% of isolates, followed by 8.21% SIT50 (H3), 5.07% SIT53 (T1), and 3.14% SIT727 (H1). Composite spoligotyping and 24-locus MIRU- VNTR minimum spanning tree analysis suggest a recent expansion of SIT42 and SIT62 evolved originally from SIT53 (T1). The proportion of Haarlem sublineage (44.3%) was significantly higher than that in neighboring countries. Associations were found between M. tuberculosis MDR and SIT45 (H1), as well as HIV-positive serology with SIT727 (H1) and SIT53 (T1). Conclusions: This study showed the population structure of M. tuberculosis in several regions from Colombia with a dominance of the LAM and Haarlem sublineages, particularly in two major urban settings (Medellı ´n and Cali). Dominant spoligotypes were LAM9 (SIT 42) and Haarlem (SIT62). The proportion of the Haarlem sublineage was higher in Colombia compared to that in neighboring countries, suggesting particular conditions of co-evolution with the corresponding human population that favor the success of this sublineage

Consenso colombiano para el manejo de pacientes con Hipofosfatasia

La hipofosfatasia (HPP) es una enfermedad metabólica, de tipo hereditario, causada por mutaciones en el gen ALPL. Teniendo en cuenta los retos del manejo adecuado de los pacientes con HPP, se realizó un consenso interdisciplinario de expertos (endocrocrinólogos pediatras, nefrólogos pediatras, ortopedistas infantiles y genetistas clínicos) con el fin de proponer recomendaciones de utilidad clínica para el diagnóstico, tratamiento y seguimiento de los pacientes colombianos con HPP. Estas sugerencias se realizan en el contexto de los diferentes tipos de presentaciones y las edades de los pacientes.Q41-7Hypophosphatasia (HPP) is a hereditary metabolic disease caused by mutations in the ALPL gene. Taking into account the challenges found in the adequate management of patients with HPP, an interdisciplinary consensus of experts (pediatric endocrinologists, pediatric nephrologists, pediatric orthopedists and clinical geneticists) was carried out, in order to propose recommendations of clinical utility for the diagnosis, treatment and follow-up of Colombian patients with HPP. These suggestions are made in the context of the different types of presentations and the ages of the patients

Antimicrobial resistance among migrants in Europe: a systematic review and meta-analysis

BACKGROUND: Rates of antimicrobial resistance (AMR) are rising globally and there is concern that increased migration is contributing to the burden of antibiotic resistance in Europe. However, the effect of migration on the burden of AMR in Europe has not yet been comprehensively examined. Therefore, we did a systematic review and meta-analysis to identify and synthesise data for AMR carriage or infection in migrants to Europe to examine differences in patterns of AMR across migrant groups and in different settings. METHODS: For this systematic review and meta-analysis, we searched MEDLINE, Embase, PubMed, and Scopus with no language restrictions from Jan 1, 2000, to Jan 18, 2017, for primary data from observational studies reporting antibacterial resistance in common bacterial pathogens among migrants to 21 European Union-15 and European Economic Area countries. To be eligible for inclusion, studies had to report data on carriage or infection with laboratory-confirmed antibiotic-resistant organisms in migrant populations. We extracted data from eligible studies and assessed quality using piloted, standardised forms. We did not examine drug resistance in tuberculosis and excluded articles solely reporting on this parameter. We also excluded articles in which migrant status was determined by ethnicity, country of birth of participants' parents, or was not defined, and articles in which data were not disaggregated by migrant status. Outcomes were carriage of or infection with antibiotic-resistant organisms. We used random-effects models to calculate the pooled prevalence of each outcome. The study protocol is registered with PROSPERO, number CRD42016043681. FINDINGS: We identified 2274 articles, of which 23 observational studies reporting on antibiotic resistance in 2319 migrants were included. The pooled prevalence of any AMR carriage or AMR infection in migrants was 25·4% (95% CI 19·1-31·8; I2 =98%), including meticillin-resistant Staphylococcus aureus (7·8%, 4·8-10·7; I2 =92%) and antibiotic-resistant Gram-negative bacteria (27·2%, 17·6-36·8; I2 =94%). The pooled prevalence of any AMR carriage or infection was higher in refugees and asylum seekers (33·0%, 18·3-47·6; I2 =98%) than in other migrant groups (6·6%, 1·8-11·3; I2 =92%). The pooled prevalence of antibiotic-resistant organisms was slightly higher in high-migrant community settings (33·1%, 11·1-55·1; I2 =96%) than in migrants in hospitals (24·3%, 16·1-32·6; I2 =98%). We did not find evidence of high rates of transmission of AMR from migrant to host populations. INTERPRETATION: Migrants are exposed to conditions favouring the emergence of drug resistance during transit and in host countries in Europe. Increased antibiotic resistance among refugees and asylum seekers and in high-migrant community settings (such as refugee camps and detention facilities) highlights the need for improved living conditions, access to health care, and initiatives to facilitate detection of and appropriate high-quality treatment for antibiotic-resistant infections during transit and in host countries. Protocols for the prevention and control of infection and for antibiotic surveillance need to be integrated in all aspects of health care, which should be accessible for all migrant groups, and should target determinants of AMR before, during, and after migration. FUNDING: UK National Institute for Health Research Imperial Biomedical Research Centre, Imperial College Healthcare Charity, the Wellcome Trust, and UK National Institute for Health Research Health Protection Research Unit in Healthcare-associated Infections and Antimictobial Resistance at Imperial College London