Diseño de un instrumento para medir estigma hacia la tuberculosis

RESUMENIntroducción: La tuberculosis continúa siendo un problema en salud pública con alta carga de la enfermedad. El efecto del estigma en el control de la TBC es desconocido porque se han realizado pocos estudios formales sobre el tema. Objetivo: Desarrollar un instrumento para medir el estigma hacia la TBC. Materiales y métodos: Estudio de evaluación de tecnología diagnóstica, con diseño del instrumento bajo las recomendaciones de Wolfe y Smith, basados en el modelo de análisis Rasch. Resultados: Se diseñó un instrumento con 35 ítems, que presentaron una adecuada comprensión por parte de las personas evaluadas. Conclusiones: El instrumento diseñado contribuirá en la medición de este constructo y en la comprensión de sus efectos en el control de la TBC.Palabras Claves: Estigma, tuberculosis, medición, instrumento. Design of an instrument for the measurement of tuberculosis stigmaABSTRACTIntroduction: Tuberculosis remains a public health problem with high burden of disease. The effect of stigma in TB control is unknown because there have been too few formal studies on the subject. Objective: To design an instrument to measure the tuberculosis stigma. Methodology: Study of diagnostic technologies evaluation, aiming at the elaboration of an instrument based on the Rasch- Analysis in accordance with the recommendations of Wolfe and Smith. Results: An instrument has been designed featuring 35 items that had been adequately understood by the persons assessed. Conclusions: The tool designed will contribute to measuring stigma and to understanding its impact on TB control.Keywords: Stigma, tuberculosis, measurement, instrument. Forma de citar: Upegui LD. Orozco LC. Diseño de un instrumento para medir estigma hacia la tuberculosis. rev.univ.ind.santander.salud 2014; 46 (1): 23-3

Diseño de un instrumento para medir estigma hacia la tuberculosis

RESUMENIntroducción: La tuberculosis continúa siendo un problema en salud pública con alta carga de la enfermedad. El efecto del estigma en el control de la TBC es desconocido porque se han realizado pocos estudios formales sobre el tema. Objetivo: Desarrollar un instrumento para medir el estigma hacia la TBC. Materiales y métodos: Estudio de evaluación de tecnología diagnóstica, con diseño del instrumento bajo las recomendaciones de Wolfe y Smith, basados en el modelo de análisis Rasch. Resultados: Se diseñó un instrumento con 35 ítems, que presentaron una adecuada comprensión por parte de las personas evaluadas. Conclusiones: El instrumento diseñado contribuirá en la medición de este constructo y en la comprensión de sus efectos en el control de la TBC.Palabras Claves: Estigma, tuberculosis, medición, instrumento. Design of an instrument for the measurement of tuberculosis stigmaABSTRACTIntroduction: Tuberculosis remains a public health problem with high burden of disease. The effect of stigma in TB control is unknown because there have been too few formal studies on the subject. Objective: To design an instrument to measure the tuberculosis stigma. Methodology: Study of diagnostic technologies evaluation, aiming at the elaboration of an instrument based on the Rasch- Analysis in accordance with the recommendations of Wolfe and Smith. Results: An instrument has been designed featuring 35 items that had been adequately understood by the persons assessed. Conclusions: The tool designed will contribute to measuring stigma and to understanding its impact on TB control.Keywords: Stigma, tuberculosis, measurement, instrument. Forma de citar: Upegui LD. Orozco LC. Diseño de un instrumento para medir estigma hacia la tuberculosis. rev.univ.ind.santander.salud 2014; 46 (1): 23-3

Neotropical tadpoles: spatial and temporal distribution and habitat use in a seasonal lake in Veracruz, México

We studied a tadpole assemblage in a seasonal neotropical lake where 14 species of anurans reproduce. Tadpoles were collected monthly at nine sampling stations at depth intervals of 1 m from the surface to the bottom (13 m). Sufficient numbers of tadpoles of three species were collected to compare habitat use. This three species assemblage breed in the following order (first to last): Smilisca baudinii, Gastrophryne usta, and Rana berlandieri. R. berlandieri had the greatest microhabitat breadth followed by S. baudinii. S. baudinii and G. usta had high microhabitat overlap, but significant differences in microhabitat use were found. S. baudinii tended to occur near the bottom, while G. usta was near the surface. This study shows that temporal and habitat partitioning both occur and depend on the species of tadpole. Dynamic interactions occur between habitat and temporal dimensions. Phenology and habitat selection depend both on the species and on abiotic and biotic factors

Study of waterborne polyurethane materials under aging treatments. Effect of the soft segment length

Coatings made of waterborne polyurethane dispersions are a promising alternative to solvent-borne ones but their mechanical and thermal properties under harsh outdoor conditions such as high temperature and humidity are somewhat limited. In this work saturated polyesters (PBA) with different molecular weights (800–2600 g/mol) were synthesized by reacting adipic acid with 1,4 butanediol. These polyols, an internal emulsifier, and an aliphatic diisocyanate were used as raw materials to synthesize polyurethane (PU) aqueous dispersions with solids contents of 29–38 wt%. The increase of the molecular weight of the polyol decreased the mean particle size of the PU dispersions from 308 to 78 nm. Polyurethane (PU) films were obtained by water evaporation of the PU dispersions and they were annealed at 80 °C for 2 h. Accelerated aging studies were performed by submerging the PU films in the water at 80 °C for 2 h. The PU films synthesized with the polyols with lower molecular weight exhibited enhanced phase miscibility, giving place to storage and loss moduli of similar magnitudes in a wide temperature range and they were less susceptible to hydrolytic degradation. Microphase miscibility was favored when shorter polyols are used. Contact angle measurement and cross-hatch adhesion test on PU coatings placed on stainless steel plate, before and after annealing and water aging were carried out. All PU coatings retained the adhesion to the substrate after aging, the PU coatings synthesized with shorter polyols exhibited enhanced adhesion.The authors thank the University of Antioquia for the “Estudiante Instructor” grant and to CODI for the economic and time support on the project 785 registered in the act 2018-19331

Digital Image Tamper Detection Technique Based on Spectrum Analysis of CFA Artifacts

Existence of mobile devices with high performance cameras and powerful image processing applications eases the alteration of digital images for malicious purposes. This work presents a new approach to detect digital image tamper detection technique based on CFA artifacts arising from the differences in the distribution of acquired and interpolated pixels. The experimental evidence supports the capabilities of the proposed method for detecting a broad range of manipulations, e.g., copy-move, resizing, rotation, filtering and colorization. This technique exhibits tampered areas by computing the probability of each pixel of being interpolated and then applying the DCT on small blocks of the probability map. The value of the coefficient for the highest frequency on each block is used to decide whether the analyzed region has been tampered or not. The results shown here were obtained from tests made on a publicly available dataset of tampered images for forensic analysis. Affected zones are clearly highlighted if the method detects CFA inconsistencies. The analysis can be considered successful if the modified zone, or an important part of it, is accurately detected. By analizing a publicly available dataset with images modified with different methods we reach an 86% of accuracy, which provides a good result for a method that does not require previous training

Digital Images Authentication Technique Based on DWT, DCT and Local Binary Patterns

In the last few years, the world has witnessed a ground-breaking growth in the use of digital images and their applications in the modern society. In addition, image editing applications have downplayed the modification of digital photos and this compromises the authenticity and veracity of a digital image. These applications allow for tampering the content of the image without leaving visible traces. In addition to this, the easiness of distributing information through the Internet has caused society to accept everything it sees as true without questioning its integrity. This paper proposes a digital image authentication technique that combines the analysis of local texture patterns with the discrete wavelet transform and the discrete cosine transform to extract features from each of the blocks of an image. Subsequently, it uses a vector support machine to create a model that allows verification of the authenticity of the image. Experiments were performed with falsified images from public databases widely used in the literature that demonstrate the efficiency of the proposed method

Inmunodiagnóstico de la infección chagásica por ELlSA

Demonstration of the infectious agent is the gold standard in parasitic infections but this is not always feasible.Thus diagnosis is confirmed through Trypanosoma cruziantibody detection (in the case of Chagas'disease) by using serological assays. In this study the enzyme immunoassay (ELISA) for the diagnosis of Trypanosoma cruz; infection was standardised and assessed. 595 serum samples taken from people coming from the endemic area of Guateque, Boyaca, were tested against T. cruziepimastigotes from the IRHOlCOl69lGuateque Colombian strain, using both the immunofluorescent antibody test (IFAT) and the ELlSA test. Analysis of the ELlSA test's validity was done through estimation of the area under the receptor-operator curve (ROC). The optimum conditions for the ELlSA test were an antigen concentration of 0.75 ygrlml and sample dilution of 1:1000. The assay's sensitivity for cut-off points of 0.2, 0.3, 0.4 and 0.5 was 0.99, 0.99, 0.98 and 0.93 and its specificity for the same cut-off points was 0.94, 0.96, 0.98 and 0.98.The ELlSA test is a valid and useful test, not only because of its sensitivity and specificity but also because the estimation of the area under the receptor-operator curve (ROC) was 0.9952, this being very close to the ideal. The ELlSA test is better than the IFAT test for detection of Trypanosoma cruzi infection antibodies and could be used in seroepidemiological sur'veys in areas of moderate to high prevalence.La demostración del agente infeccioso es la regla de oro en las parasitosis, pero, esto no siempre es factible. Por ello, en la infección chagásica ce recurre a la detección de anticuerpos contra Trypanosoma cruzi siendo las pruebas serodiagnósticas de gran utilidad. El presente estudio estandarizó y evaluó la prueba inmunoenzimática Elisa para el inmunodiagnóstico de la infección chagásica. Se confrontaron 595 muestras de suero de pacientes provenientes de Guateque, Boyacá, zona endémica de la enfermedad de Chagas, con epimastigotes de Tcruzide la cepa colombiana IRHOICO/69/Guateque utilizando las pruebas inmunodiagnósticas de inmunofluorescencia indirecta (IFI), prueba de referencia, y el ensayo inmunoenzimático ELISA. El análisis de la validez de ésta se realizó mediante el cálculo del área bajo la curva del operador receptor (ROC) como medida de la exactitud (validez). Las condiciones óptimas de la prueba ELlSA fueron: antígeno 0,75 pglml y dilución de la muestra 1:1.000. El ensayo del estudio según los puntos de corte 0,2, 0,3, 0,4 y 0,5 ofrece una sensibilidad de 0,99, 039, 0,98 y 0,93 y una especificidad de 0,94, 0,96, 0,98 y 0,98, respectivamente. El ELlSA del estudio se muestra como una prueba válida no sólo por la sensibilidad y especificidad sino porque el análisis del área bajo la curva ROC fue de 0,9952 que es muy cercano al ideal. La prueba de ELlSA es superior a la de IFI para la detección de anticuerpos contra 1 cruzi y podría ser utilizada en estudios seroepidemiológicos en zonas de alta y moderada prevalencia

Corrosión electroquímica de los aceros inoxidables 410 y 304 en sistemas de enfriamiento de aceite para transmisión.

En este trabajo se analizan las causas y grado de corrosión que se presenta en la parte externa de los intercambiadores de calor de aceite para transmisión automática, elaborados con placas de acero inoxidable 304 o 410. Se determinó la velocidad de corrosión de los especímenes empleando la técnica electroquímica de resistencia a la polarización lineal, con un sistema de tres electrodos y tres medios de exposición (H2O, solución salina usada por la industria automotriz (OY) y anticongelante automotriz) a 25 y 60°C. Se observó que el acero inoxidable 304 contaminado con cobre presenta una cinética de corrosión mayor que el mismo acero no contaminado y que el acero 410 no contaminado con cobre