A system was developed to identify and quantify up to seven species of helminth eggs (Ascaris lumbricoides -fertile and unfertile eggs-, Trichuris trichiura, Toxocara canis, Taenia saginata, Hymenolepis nana, Hymenolepis diminuta, and Schistosoma mansoni) in wastewater using different image processing tools and pattern recognition algorithms. The system was developed in three stages. Version one was used to explore the viability of the concept of identifying helminth eggs through an image processing system, while versions 2 and 3 were used to improve its efficiency. The system development was based on the analysis of different properties of helminth eggs in order to discriminate them from other objects in samples processed using the conventional United States Environmental Protection Agency (US EPA) technique to quantify helminth eggs. The system was tested, in its three stages, considering two parameters: specificity (capacity to discriminate between species of helminth eggs and other objects) and sensitivity (capacity to correctly classify and identify the different species of helminth eggs). The final version showed a specificity of 99% while the sensitivity varied between 80 and 90%, depending on the total suspended solids content of the wastewater samples. To achieve such values in samples with total suspended solids (TSS) above 150 mg/L, it is recommended to dilute the concentrated sediment just before taking the images under the microscope. The system allows the helminth eggs most commonly found in wastewater to be reliably and uniformly detected and quantified. In addition, it provides the total number of eggs as well as the individual number by species, and for Ascaris lumbricoides it differentiates whether or not the egg is fertile. The system only requires basically trained technicians to prepare the samples, as for visual identification there is no need for highly trained personnel. The time required to analyze each image is less than a minute. This system could be used in central analytical laboratories providing a remote analysis service.

RESUMEN

When a lesion occurs in a blood vessel, a series of mechanisms are activated to stop hemorrhage by increasing blood viscosity at the wounded place.If a sample of blood extracted of the human body is illuminated with coherent light, a time varying speckle pattern is observed. It is show high activity at the start and decreases with time until it finally stop.The analysis of these patterns shows a degree of correlation between speckle activity and the temporal evolution of the clot.These preliminary results are promising for the continuation of studies aiming to the application of biospeckle techniques to the analysis of coagulation times.

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ResumenEl acceso a imágenes fuera del espectro visible ha abierto grandes posibilidades para la caracterización de procesos y materiales en muchas áreas de la actividad humana; particularmente, las termografías son notablemente útiles en el estudio del comportamiento de los fenómenos de propagación del calor; en este caso, los análisis se han limitado a verificar distribuciones de calor en un momento dado y solo estáticamente. El enlace temporal de las isotermas y de los centros de generación del calor permite obtener información de carácter dinámico y realizar análisis más completos sobre el comportamiento de los equipos o materiales bajo estudio. En este trabajo se presentan los resultados de aplicar técnicas de análisis de secuencias de imágenes a termografías de diferentes procesos; se demuestra que con ellas se logra un entendimiento más preciso del comportamiento del calor al circular por los objetos, de cómo sus fuentes y sumideros asimilan diferentes condiciones y de la evolución general de flujos constantes o variables de perfiles de temperatura.Palabras clave: Termografía infrarroja, Procesamiento de imágenes, Análisis de materiales. AbstractAccess to images out of visible spectrum range has opened a wide field of possibilities for processes and material characterization in many areas of human activity. Thermography is particularly useful in analyzing the behavior of heat propagation phenomena. In this case, the analysis has been limited to verify the heat distribution at a given time, it means, the static aspect of the phenomena. The temporary connection of isotherms and heat generation areas can yield dynamic information that enables a more comprehensive analysis of equipment or materials behavior of interest. This paper presents the results obtained from the application of analytical techniques in different processes of some image sequences. The results show that it achieves a more precise understanding of the heat behavior circulation through the objects, it also reveals how sources and sinks assimilate the different conditions and the temperature profiles trends of constant or variable flow's general evolution.