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La enseñanza aprendizaje se convierte en una estrategia de la educación desde el constructivismo. El objetivo de este estudio es analizar la enseñanza aprendizaje desde una síntesis del análisis conceptual del enfoque centrado en procesos. En cuanto a la metodología se destaca desde un análisis documental realizado desde una búsqueda sistemática en bases de datos internacionales como: Scielo, Dialnet, Web of Science, Scopus y Ebsco. Los resultados dan cuenta que el enfoque basado en el proceso de enseñanza-aprendizaje se apoya con el modelo constructivista, por lo tanto, todo conocimiento que se construye corresponde al pensamiento y las diversas formas de su interiorización desde el ser. Se concluye que los entornos educativos, condicionan los procesos de enseñanza aprendizaje, y la influencia de los métodos de participación en los mismos sistematizan la formación en investigación.

T-cell self-recognition of antigen presenting molecules is led by antigen-dependent or independent mechanisms. The endothelial protein C receptor (EPCR) shares remarkable similarity with CD1d, including a lipid binding cavity. We have identified EPCR-specific α/β T-cells in the peripheral blood of healthy donors. The average frequency in the CD3+ leukocyte pool is comparable to other autoreactive T-cell subsets that specifically bind MHC-like receptors. Alteration of the EPCR lipid cargo, revealed by X-ray diffraction studies, points to a prevalent, yet not exclusive, lipid-independent self-recognition. In addition, we solve the EPCR lipidome, and detect species not yet described as EPCR ligands. These studies report, for the first time, novel recognition by circulating α/β T-cells and provide grounds for EPCR and lipid mediated T-cell restriction.

El presente artículo aborda inicialmente el concepto de salud mental visto desde la legislación colombiana. Luego menciona los trastornos mentales de mayor prevalencia en el país describiéndolos en forma breve y señalando la importancia que se le ha dado a este tópico en el contexto nacional. Posteriormente se explican los diferentes efectos del medio carcelario en la salud mental de los individuos aludiendo a diversas teorías que explican de manera clara esta afectación. Además se comenta la prevalencia de trastornos mentales en las personas privadas de la libertad haciendo mayor énfasis en el fenómeno del suicidio. Finalmente se hace referencia a la situación actual de la atención de la salud mental en las cárceles del país.

The aim of this study was to construct and internally validate a scoring system to estimate the probability of death in hypertensive inpatients. Existing predictive models do not meet all the indications for clinical application because they were constructed in patients enrolled in clinical trials and did not use the recommended statistical methodology. This cohort study comprised 302 hypertensive patients hospitalized between 2015 and 2017 in Spain. The main variable was time-to-death (all-cause mortality). Secondary variables (potential predictors of the model) were: age, gender, smoking, blood pressure, Charlson Comorbidity Index (CCI), physical activity, diet and quality of life. A Cox model was constructed and adapted to a points system to predict mortality one year from admission. The model was internally validated by bootstrapping, assessing both discrimination and calibration. The system was integrated into a mobile application for Android. During the study, 63 patients died (20.9%). The points system prognostic variables were: gender, CCI, personal care and daily activities. Internal validation showed good discrimination (mean C statistic of 0.76) and calibration (observed probabilities adjusted to predicted probabilities). In conclusion, a points system was developed to determine the one-year mortality risk for hypertensive inpatients. This system is very simple to use and has been internally validated. Clinically, we could monitor more closely those patients with a higher risk of mortality to improve their prognosis and quality of life. However, the system must be externally validated to be applied in other geographic areas.

La niñez es una etapa fundamental para el óptimo desarrollo físico, social, psicológico y biológico de la persona; en su desarrollo inciden aspectos individuales, familiares, culturales, sociales e históricos. El presente artículo muestra la incidencia de diferentes contextos en la aparición de problemas a nivel mental en niños, niñas y adolescentes, examinando los determinantes sociales y explicando su relación en la aparición de diversas alteraciones a nivel mental en este grupo poblacional. Se destaca la familia como red primaria de los niños en el desarrollo de conductas prosociales, la autorregulación emocional y su importancia en la prevención de problemas de salud mental. Asimismo, se plantea la importancia del desarrollo de la resiliencia infantil y el papel preponderante de la autoestima como factor protector de la salud mental.

RESUMEN Las infecciones víricas por Epstein-Barr (EBV) y Adenovirus (AdV) representan una causa significativa de morbi-mortalidad en pacientes sometidos a un trasplante alogénico de progenitores hematopoyéticos debido al uso de tratamientos inmunomielosupresores y al prolongado periodo de inmunodeficiencia que generan. Hasta el momento, se ha demostrado el papel protector post-trasplante de los linfocitos T CD8+ (CTLs) específicos de EBV y AdV. Sin embargo, otros factores son cada vez más importantes en la regulación de la reconstitución y actividad de CTLs específicos para estos virus, como las diferentes subpoblaciones celulares (linfocitos T CD4+, linfocitos T reguladores, células dendríticas, células Natural Killer, etc.), mecanismos moleculares de inmunoregulación y los fármacos administrados al paciente como profilaxis para una posible enfermedad de injerto contra huésped. El objetivo de esta revisión es analizar la importancia de la monitorización de la respuesta celular específica funcional frente a EBV y AdV en el manejo de los pacientes post-trasplante.

Las pérdidas y desperdicios de alimentos (PDA) se originan en el campo hasta su transformación y consumo, generando un impacto negativo en los recursos naturales (agua y suelo) y pérdida de nutrientes (energía y proteína). Las PDA pueden emplearse en la alimentación animal mediante su transformación y enriquecimiento, favoreciendo la conservación ambiental y conduciendo a una “producción orgánica”. Se han realizado estudios caracterizando nutricionalmente las PDA ofrecidas en distintas formas, proporción y mezcla, así como, su relación con el desempeño animal, obteniendo resultados alentadores de conversión, ganancia de peso y desempeño reproductivo. Es así que en ésta revisión se presentan algunas alternativas en el uso de residuos de plato con alternativas que reducen la carga microbiana y su uso en alimentación de cerdos con valores que han sido favorables para la producción. Además, se ha propuesto al ensilaje como estrategia para su aprovechamiento de los PDA, y como una alternativa de bajo costo para economías campesinas y sistemas de producción sostenibles amigables con el medio ambiente.

Comprehensive gas chromatography-mass spectrometry (GC×GC-MS) provides a different perspective in metabolomics profiling of samples. However, algorithms for GC×GC-MS data processing are needed in order to automatically process the data and extract the purest information about the compounds appearing in complex biological samples. This study shows the capability of independent component analysis-orthogonal signal deconvolution (ICA-OSD), an algorithm based on blind source separation and distributed in an R package called osd, to extract the spectra of the compounds appearing in GC×GC-MS chromatograms in an automated manner. We studied the performance of ICA-OSD by the quantification of 38 metabolites through a set of 20 Jurkat cell samples analyzed by GC×GC-MS. The quantification by ICA-OSD was compared with a supervised quantification by selective ions, and most of the R(2) coefficients of determination were in good agreement (R(2)>0.90) while up to 24 cases exhibited an excellent linear relation (R(2)>0.95). We concluded that ICA-OSD can be used to resolve co-eluted compounds in GC×GC-MS.

Background: Hydatidosis is an endemic zoonosis in Chile. We report a 48-year-old former slaughterman, with a previous history of pulmonary hydatidosis, who presented a stroke without associated cardiovascular symptoms. An echocardiogram revealed a tumor mass with cystic features in the left ventricle. The patient was operated and the cyst was successfully excised. During the follow up, the patient remains asymptomatic.

Introducción: Se estima que 1 de cada 1.000 niños presenta hipoacusia severa al nacimiento o en los primeros meses de vida y el 50% de las hipoacusias congénitas se relacionan con el gen de la conexina 26 (GJB2). En poblaciones caucásicas la variante patogénica 35delG del gen GJB2, que es la más frecuente, se encuentra en 30°% de los pacientes con hipoacusia congénita no sindrómica. En Chile, la frecuencia de esta variante en escolares sordos no está descrita. Objetivos: Estimar la frecuencia de la mutación 35delG del gen GJB2 en niños con sordera congénita no sindrómica y no atribuible a causas ambientales conocidas, de colegios especiales de Santiago. Correlacionar la presencia de 35delG con los antecedentes clínicos de estos niños. Material y método: Se determinó la presencia de la mutación 35delG mediante PCR alelo específico y secuenciación automatizada en 81 escolares. Se buscó asociar la presencia de 35delG y los antecedentes clínicos de los niños mediante la prueba exacta de Fisher. Resultados: En el grupo estudiado, el 11,25°% de los casos presentaron la variante 35delG, siendo ésta más frecuente en los casos en que había antecedentes familiares de sordera. En 8 casos se encontró una variante considerada no patogénica V27I. Conclusión: La frecuencia de la mutación 35delG fue inferior a lo esperado, probablemente debido al método de selección de los niños a estudiar (aquellos cuyos padres no referían causa conocida de sordera, lo cual no fue refrendado por exámenes de laboratorio que permitieran descartar enfermedades infecciosas u otras condiciones causantes de sordera).

Metabolomics GC-MS samples involve high complexity data that must be effectively resolved to produce chemically meaningful results. Multivariate curve resolution-alternating least squares (MCR-ALS) is the most frequently reported technique for that purpose. More recently, independent component analysis (ICA) has been reported as an alternative to MCR. Those algorithms attempt to infer a model describing the observed data and, therefore, the least squares regression used in MCR assumes that the data is a linear combination of that model. However, due to the high complexity of real data, the construction of a model to describe optimally the observed data is a critical step and these algorithms should prevent the influence from outlier data. This study proves independent component regression (ICR) as an alternative for GC-MS compound identification. Both ICR and MCR though require least squares regression to correctly resolve the mixtures. In this paper, a novel orthogonal signal deconvolution (OSD) approach is introduced, which uses principal component analysis to determine the compound spectra. The study includes a compound identification comparison between the results by ICA-OSD, MCR-OSD, ICR and MCR-ALS using pure standards and human serum samples. Results shows that ICR may be used as an alternative to multivariate curve methods, as ICR efficiency is comparable to MCR-ALS. Also, the study demonstrates that the proposed OSD approach achieves greater spectral resolution accuracy than the traditional least squares approach when compounds elute under undue interference of biological matrices.

En este articulo se presenta el diseno conceptual de una alternativa complementaria de la solucion al manejo de las aguas asociadas de produccion dentro de un marco ambiental y tecnico factible, cuyo fin es la recuperacion de la sal de mayor porcentaje, mediante un proceso de cristalizacion fraccionada tipo Paro plantear y analizar la alternativa de trabajo con los aguas asociadas de produccion provenientes de las estaciones La Gloria, La Gloria Norte y Morichal, pertenecientes o la Asociacion Casanare, dado que las anteriores producen un afluente con alto contenido de sales, la propuesta esta enfocada al tratamiento del 30% del volumen de agua asociada producida, esperada para el ano 2000 (1239 m3/dia) en los campos de estudio. El proceso permite recuperar un 92% de NaCi presente, equivalente a 0.918 Ton/h, con una pureza del 97%. Para garantizar la calidad del producto final y aprovechar las facilidades del campo, se proponen sistemas de aireacion y evaporacion previos a la etapa de cristalizacion.

10.1016/j.envint.2014.06.012 In addition to passive inhalation, non-smokers, and especially children, are exposed to residual tobacco smoke gases and particles that are deposited to surfaces and dust, known as thirdhand smoke (THS). However, until now the potential cancer risks of this pathway of exposure have been highly uncertain and not considered in public health policy. In this study, we estimate for the first time the potential cancer risk by age group through non-dietary ingestion and dermal exposure to carcinogen N-nitrosamines and tobacco-specific nitrosamines (TSNAs) measured in house dust samples. Using a highly sensitive and selective analytical approach we have determined the presence of nicotine, eight N-nitrosamines and five tobacco-specific nitrosamines in forty-six settled dust samples from homes occupied by both smokers and non-smokers. Using observations of house dust composition, we have estimated the cancer risk by applying the most recent official toxicological information. Calculated cancer risks through exposure to the observed levels of TSNAs at an early life stage (1 to 6. years old) exceeded the upper-bound risk recommended by the USEPA in 77% of smokers' and 64% of non-smokers' homes. The maximum risk from exposure to all nitrosamines measured in a smoker occupied home was one excess cancer case per one thousand population exposed.The results presented here highlight the potentially severe long-term consequences of THS exposure, particularly to children, and give strong evidence of its potential health risk and, therefore, they should be considered when developing future environmental and health policies.

10.1016/j.chroma.2011.11.017 A novel, highly selective method for the determination of nicotine, N-nitrosamines and tobacco-specific nitrosamines (TSNAs) in indoor dust samples is presented in this study. Samples were extracted by in-cell clean-up pressurized liquid extraction (PLE) that allows high extraction efficiency with moderate consumption of organic solvents. The extracts were analyzed by comprehensive gas chromatography and detected with a nitrogen chemiluminiscence detector (GC × GC-NCD) that provided enhanced selectivity and sensitivity for organic nitrogen containing compounds. Method validation showed good linearity, repeatability and reproducibility (%RSD < 8%). Recovery was higher than 80% for most target compounds and limits of detection lower than 16 ng g-1. The method was used for the determination of the nitrosamine target compounds in house dust samples from both smoking and non-smoking households. All the analytes were found in the samples, nicotine being the most abundant compound in smokers¿ dust and one of the most abundant in non-smokers¿ dust. To our knowledge this is the first time that volatile N-nitrosamines and TSNAs have been determined in indoor dust samples. The results demonstrate the presence of these highly carcinogenic compounds in house dust, with inherent human exposure through inhalation and/or involuntary ingestion of house dust.

10.1016/j.envint.2011.11.002 This study focuses on characterising the risk of exposure to volatile organic compounds (VOCs) by means of inhalation in people living in the vicinity of the largest chemical production site in the Mediterranean area. Eighty-six VOCs were initially selected for this study based on their adverse environmental and health effects. The monitoring campaign was conducted for 276 days in three different locations around the chemical site. The analytical method used for the characterisation was based on European standard method EN-14662-2, which consists of the active sampling of air for 24 h in charcoal tubes, followed by extraction with carbon disulphide and GC¿MS analysis. Forty-four VOCs with toxicological data available concerning their carcinogenic and non-carcinogenic health effects were quantified during the monitoring campaign. None of the quantified VOCs showed average concentrations exceeding their chronic reference concentrations and, therefore, no non-carcinogenic health effects are expected as a result of this exposure. However, the global average cancer risk due to VOC exposure in the area (3.3 × 10- 4) was found to be above the values recommended by the WHO and USEPA. The influence of the analytical method was also evaluated by comparing cancer risk estimates using a thermal desorption (TD) method based on method EN-14662-1. The results of the 24-h samples for the solvent extraction method were compared with the average of 12 daily samples of 2-h for the TD method for 24 sampling days. Although the global estimated lifetime cancer risk was statistically comparable for both methods, some differences were found in individual VOC risks. To our knowledge, this is the first study that estimates the carcinogenic and non-carcinogenic risks

Background: Since the introduction of stents in 1994, improved clinical results have boosted the development of coronary angioplasty in Chile. Drug eluting stents, that have a reduced rate of restenosis, are being increasingly used. Aim: To assess the acute and long-term results of bare metal stent implantation. Patients and Methods: Acute and long-term clinical, procedural and angiographic results were assessed in non acute myocardial infarction patients undergoing coronary stent implantation between August 1996 and December 2003. Results: During the study period, 932 patients aged 30 to 87 years (194 women) had at ¡east one stent implanted. Twenty two percent were diabetic, 33% had recent myocardial infarction, 53% unstable angina and 22% stable angina. Angiographic and clinical success were 99.6% and 98.2%, respectively. In hospital death was 0.5%. During a mean follow-up of 19.1 months, all cause mortality was 3.9%, cardiac death 1.9% and survival free of major cardiac ischemic events was 85.3%. Only 6.4% of lesions underwent target vessel revascularization (TVR). Independent predictors of TVR were previous surgery, ¡eft anterior descending artery, small post stent minimum luminal diameter. Ostial location, in-stent restenosis, and younger age were non significant predictors. Conclusions: Acute and long-term results of bare metal stents in this population were excellent. An intriguingly low rate of TVR was seen. Selective bare metal stenting should continue in lesions and patients with a low risk of clinical restenosis

The Calgary Depression Scale for Schizophrenia (CDSS) is a valid tool to assess depression in schizophrenics and has been translated, adapted, and validated to be used in different non-English languages. Therefore, it may be predicted that a Spanish version of this scale will be also a valid instrument to assess symptoms of depression in patients with schizophrenia.

We report a previously healthy 73 years old woman, who was hospitalised with increasing dyspnea and signs of congestive heart failure. Echocardiography showed a normal left ventricular cavity with increased echogenicity of its walls and severe pulmonary hypertension. A lung ventilation/perfusion scintigraphy concluded that there was a low probability for pulmonary embolism. Coronary angiography was normal. A restrictive cardiomyopathy due to amyloid deposits was suspected. Myocardial pyrophosphate scintigraphy showed intense pyrophosphate uptake in the left ventricle wall. An abdominal fat tissue biopsy was positive for amyloid deposits (Rev Méd Chile 2002; 130: 315-8)

Background. The classification of coronary lesion complexity, using the American College of Cardiology/American Heart Association (ACC/AHA) is a predictor of balloon angioplasty success. Stents have improved results even in complex lesions. Aim. To compare the ACC/ AHA and the new Society for Cardiac Angiography (SCAepsilonI) coronary lesion scores as predictors of angioplasty success. Patients and Methods. Alí consecutive angioplasty procedures (n=346, 456 lesions, 47% stents) were prospectively analized from August 1996 to March 1999. Coronary lesions were classified using the ACC/AHA and SCA&I scores. Angiographic success was assesed and its multivariate predictors determined with logistic regression analysis. Results. According to the ACC/AHA score, angiographic success was 97, 92.7, 93.3, and 82.3% in A, Bl, B2 and C lesions respectively (p=0.013). There only were significant differences in success between C and A, Bl or B2 lesions. According to the SCAepsilonI score success was achieved in 97.3, 97.9, 75.8 and 33.3% in nonCP, CP, nonCO and CO lesions respectively (P

We report a 50-year-old woman with a recent myocardial infarction in whom a myocardial perfusion single photon emission computed tomography (SPECT) with Thallium201201Tl SPECT to study viability and a FDG-SPECT with a dual head high-energy collimator camera were done. Images, acquired 45 min after injection, were analyzed visually. In anterior and medial apical sectors, discordance between flux and metabolism, considered a classical mismatch, was observed. Echocardiographic hypokinesia disappeared three month after revascularization (Rev Méd Chile 2000; 128: 1019-23).

Resumen tomado de la revista El objetivo de este trabajo es analizar la estructura factorial de la segunda versión del B.D.I. (Beck Depression Inventory, B.D.I.; Beck, Rush, Shaw y Emery, 1979) en una muestra de 249 padres de niños con trastornos psicopatológicos. Se realizó un análisis factorial de componentes principales (rotación oblimin) y se extrajeron dos factores de primer orden: el primero relacionado con el componente cognitivo de la depresión y el segundo con el somático. El índice de consistencia interna para todo el inventario fue alto: 0,84. El alpha de Cronbach para los factores fue más bajo: 0,80 para el factor cognitivo y 0,71 para el somático. Los datos coinciden con los hallados en otras investigaciones españolas o extranjeras realizadas con muestras comunitarias.. Valencia ESP

TiAlNO coatings were obtained on corning glass by means of the co-sputtering technique. Two series were fabricated. In the first one the argon flux was maintained at 12 sccm, while the nitrogen flux was varied in 3, 6 and 9 sccm; in the second one the argon flux was 15 sccm and the nitrogen flux was varied in 2, 3, 4, 5 and 6 sccm, which produced a working pressure variation. For co-sputtering in the first series, three targets were occupied: titanium, alumina and aluminium; meanwhile in the second series, two targets were used: titanium monoxide and aluminium plus an amount of titanium, specifically, 3.5 gr in the aluminium target, occupying 40% of the total effective area of the target. Structural, mechanical and electrical properties were obtained through X-ray diffraction, the Vickers microhardness test and resistivity probes, respectively. For first series, X-ray diffraction detected titanium nitride (TiN) in the crystalline phase; for the second series, aluminium nitride and titanium oxide (TiO)3.38. The difference in the crystalline structure obtained for the series explains the microhardness values; in the first series a maximum value of 20.4 GPa at 2 sccm of nitrogen was obtained, whereas in the second series the maximum value obtained was 8 GPa. As one can observe, the increase in nitrogen flux is not an advantage to hardness, but in electrical resistivity it has a positive effect. The results suggest that TiAlNO is versatile material that could be used for both mechanical and electronic applications; however, it is important to control fabrication conditions.

En cultivos de algodonero del Sinú, de 80 días de edad, se presentó durante la cosecha 83-84 una malformación de botones y "capullos" que al ocasionar la caída de las estructuras del tercio supe­rior pudo reducir la producción hasta en 700 Kg./ha, según estimativos pre­liminares. En muchos casos, la malfor­mación estuvo seguida por una pudri­ción bacterial producida por Pseudomonas sin tener aún claridad sobre la relación patógeno-insecto. La especie responsable de estos daños Contarinia gossypii (Diptera: Cecido­míidae) tiene larvas rosáceas, de 2 mm. de longitud cuando maduras, las cuales se alimentan internamente de pétalos y androceo, pudiéndose encontrar hasta 185 de ellas por botón de 6 mm. de diámetro. Las larvas abandonan las estructuras atacadas mediante un salto caracterís­tico para empupar en el suelo. Las pu­pas son obtectas, oscuras, de 1,2 mm de largo y protegidas por un cocon se­doso el cual se encuentra a poca pro­fundidad de la superficie del suelo. Los adultos son típicos cecidomyíidos de antenas y patas muy largas, recu­biertos de pilosidad oscura y densa que les da un aspecto de diminutas mosqui­tas grisáceas; miden aproximadamente de 1 a 2 mm. de longitud. Observaciones de laboratorio indican que la emer­gencia ocurre en las últimas horas de la tarde. Como enemigo natural se ha encontra­do un parásito de larvas de la familia Platygasteridae, cuyos puparios tam­bién se encuentran en el suelo. Fuera del algodonero no se ha encon­trado otra planta hospedante. Los re­gistros de C. gossípii en Cereté, Mon­tería, San Carlos, San Pelayo, Ciénaga de Oro y Lorica señalan su amplia dis­tribución en el Departamento de Cór­doba.

Resumen Objetivo Determinar la incidencia de violencia extrema contra la mujer (VECM) y feminicidio, así como algunos factores de riesgo en el Perú entre los años 2009 y 2014. Método Investigación observacional de datos secundarios (2009-2014) del Observatorio de Criminalidad del Ministerio Público. Resultados Tacna (razón de tasas [RT] = 3,144; intervalo de confianza del 95% [IC95%] = 2,622-3,770), Madre de Dios (RT = 2,611; IC95% = 1,828-3,730), Junín (RT = 2,302; IC95% = 2,017-2,627), Ayacucho (RT = 2,101; IC95% = 1,720-2,567) y Huánuco (RT = 1,393; IC95% = 1,199-1,619) tuvieron mayor riesgo de feminicidio. En enero existe mayor riesgo de VECM (RT = 1,329; IC95% = 1,090-1,622) y feminicidio (RT = 1,427; IC95%: 1,139-1,789). Existe mayor riesgo de que la VECM culmine en feminicidio cuando la víctima es ≤12 años (odds ratio cruda [ORc] = 8,698; IC95% = 2,482-53,660) o ≥65 años (ORc = 8,263; IC95% = 1,525-173,100), cuando el agresor es desconocido (ORc = 4,697; IC95% = 1,599-19,360), conocido (ORc = 4,216; IC95% = 1,626-13,910), familiar (ORc = 2,150; IC95% = 1,260-3,843) o pareja (ORc = 1,337; IC95% = 1,008-1,772). Conclusiones Existe mayor riesgo de VECM y feminicidio en enero; asimismo, el riesgo de feminicidio es mayor cuando la VECM se produce en un escenario no íntimo y perpetrado por un desconocido.

This work presents an experimental study of solids suspension in upward annular flow using non-Newtonian biopolymer solutions as liquid phases. The biopolymers employed were xanthan and guar gums, and the solid phase consisted of silica sand with a mean particle size of 250 μm. The experimental equipment is a vertical concentric pipe system, with 3 m of height and a hydraulic diameter of 0.15 m, simulating the drilling process at room temperature without the drill rotation effects. The annular velocity, concentration of load and polymer were the most important variables studied. It was found that the transport ratio allows a simple quantification of the effects of the polymer as a viscosifying additive in drilling muds, independently of the solids loading. xanthan gum provides a better suspension capacity than Guar gum at similar concentrations, especially at low flow velocities, while at high velocities the solids transport is similar for both polymeric solutions, due to their pseudoplasticity. El siguiente trabajo presenta un estudio experimental de la suspensión de sólidos en flujo anular vertical, usando soluciones no-newtonianas de biopolímeros como fase líquida. Los biopolímeros empleados fueron goma xantano y goma guar, y la fase sólida consistió en arena de sílice con un diámetro promedio particular de 250 μm. El equipo experimental es un sistema de tubos concéntricos con 3 m de altura y un diámetro hidráulico de 0,15 m, que simulan el proceso de perforación de pozos a temperatura ambiente y sin el efecto de la rotación de la mecha. Las variables estudiadas más importantes fueron la velocidad anular, la concentración de carga y de polímero. Se obtuvo que la relación de transporte permite una cuantificación simple del efecto del polímero como un aditivo viscosificante en lodos de perforación, independientemente la concentración de carga utilizada. La goma xantano provee una mejor capacidad de suspensión que la goma guar a concentraciones similares, especialmente a bajas velocidades de flujo, mientras que a altas velocidades el transporte de solidos es similar para soluciones de ambos polímeros, debido a la pseudoplasticidad de las mismas.