839 resultados para apnea del sonno, beat detection, respirazione, monitoraggio respiro, filtrare respiro.
Resumo:
El ciclo ecológico de los baculovirus comprende dos vías de transmisión: la horizontal que se produce entre congéneres y la vertical, que implica el paso de genomas virales de los parentales a la progenie. Recientemente se ha estudiado la efectiva transmisión vertical del Nucleopoliedrovirus de Spodoptera exigua (SeMNPV-Al1) en una población de su húesped de los invernaderos de Almería (España). La detección de progenie infectada de hembras sanas, sugiere la necesidad de determinar el papel que juegan ambos sexos en la transmisión del virus. En el presente trabajo se establecieron infecciones subletales para obtener adultos con infecciones encubiertas y utilizando un esquema de apareamientos entre adultos sanos e infectados se verificó que la transmisión del virus es posible vía paterna o materna. La vía materna parece más constante en su respuesta de acuerdo a la medición de la carga viral obtenida en la descendencia (qPCR). El tratamiento de desinfección de la puesta no afectó a la detección de ADN viral en la descendencia, lo que sugiere una transmisión transovo. La carga viral por insecto fue similar independientemente del sexo de los parentales y la descendencia masculina y femenina se vio afectada de igual manera por la infección.
Resumo:
La termometría es una técnica no invasiva que permite cuantificar los cambios en la temperatura cutánea y evaluarla de forma cuantitativa. El aumento significativo de la temperatura puede indicar la existencia de patología. Se ha demostrado que la actividad muscular induce procesos de transferencia de calor entre los músculos y las capas superficiales de tejido. En este estudio queremos cuantificar los cambios de temperatura que se producen en los músculos del pie y miembro inferior tras una carrera de 30 km, para ello hemos utilizado una cámara termográfica de alta resolución. Contamos con la colaboración voluntaria de 32 sujetos sanos a los que procedimos a tomar fotografías de la planta del pie, parte anterior de la pierna, parte posterior de la pierna, parte anterior del muslo y parte posterior del muslo en dos etapas, primero antes de la carrera y segunda toma después de la carrera de 30 km, de esta manera pudimos valorar si había o no variación de temperatura en las zonas seleccionadas. Tras el análisis de los datos obtenidos encontramos significativas variaciones térmicas en Talón, cabeza primer metatarsiano, cabeza segundo metatarsiano, cabeza tercer metatarsiano, cabeza cuarto metatarsiano, cabeza quinto metatarsiano, apófisis estiloides quinto metatarsiano, arco longitudinal interno, maléolo interno, maléolo externo, peroneo lateral largo, vasto interno, vasto externo, recto femoral, tensor de la fascia lata, inserción cuádriceps, gemelo interno, tendón de Aquiles y Biceps femoral.
Resumo:
Color segmentation of images usually requires a manual selection and classification of samples to train the system. This paper presents an automatic system that performs these tasks without the need of a long training, providing a useful tool to detect and identify figures. In real situations, it is necessary to repeat the training process if light conditions change, or if, in the same scenario, the colors of the figures and the background may have changed, being useful a fast training method. A direct application of this method is the detection and identification of football players.
Resumo:
In this paper we propose a statistical model for detection and tracking of human silhouette and the corresponding 3D skeletal structure in gait sequences. We follow a point distribution model (PDM) approach using a Principal Component Analysis (PCA). The problem of non-lineal PCA is partially resolved by applying a different PDM depending of pose estimation; frontal, lateral and diagonal, estimated by Fisher's linear discriminant. Additionally, the fitting is carried out by selecting the closest allowable shape from the training set by means of a nearest neighbor classifier. To improve the performance of the model we develop a human gait analysis to take into account temporal dynamic to track the human body. The incorporation of temporal constraints on the model increase reliability and robustness.
Resumo:
In this paper we propose a novel automated glaucoma detection framework for mass-screening that operates on inexpensive retinal cameras. The proposed methodology is based on the assumption that discriminative features for glaucoma diagnosis can be extracted from the optical nerve head structures,
such as the cup-to-disc ratio or the neuro-retinal rim variation. After automatically segmenting the cup and optical disc, these features are feed into a machine learning classifier. Experiments were performed using two different datasets and from the obtained results the proposed technique provides
better performance than approaches based on appearance. A main advantage of our approach is that it only requires a few training samples to provide high accuracy over several different glaucoma stages.
Resumo:
The increasing occurrence of puffer fish containing tetrodotoxin (TTX) in the Mediterranean could represent a major food safety risk for European consumers and threaten the fishing industry. The work presented herein describes the development of a new enzyme linked immunosorbent assay (mELISA) based on the immobilization of TTX through dithiol monolayers self-assembled on maleimide plates, which provides an ordered and oriented antigen immobilization and favors the antigen-antibody affinity interaction. The mELISA was found to have a limit of detection (LOD) of TTX of 0.23 mg/kg of puffer fish matrix. The mELISA and a surface plasmon resonance (SPR) immunosensor previously developed were employed to establish the cross-reactivity factors (CRFs) of 5,6,11-trideoxy-TTX, 5,11-deoxy-TTX, 11-nor-TTX-6-ol, and 5,6,11-trideoxy-4-anhydro-TTX, as well as to determine TTX equivalent contents in puffer fish samples. Results obtained by both immunochemical tools were correlated (R(2) = 0.977). The puffer fish samples were also analyzed using liquid chromatography-tandem mass spectrometry (LC-MS/MS), and the corresponding CRFs were applied to the individual TTX contents. Results provided by the immunochemical tools, when compared with those obtained by LC-MS/MS, showed a good degree of correlation (R(2) = 0.991 and 0.979 for mELISA and SPR, respectively). The mouse bioassay (MBA) slightly overestimated the CRF adjusted TTX content of samples when compared with the data obtained from the other techniques. The mELISA has been demonstrated to be fit for the purpose for screening samples in monitoring programs and in research activities.
Resumo:
By the end of 2004, the Canadian swine population had experienced a severe 2 increase in the incidence of Porcine circovirus-associated disease (PCVAD), a problem that was 3 associated with the emergence of a new Porcine circovirus-2 genotype (PCV-2b), previously 4 unrecovered in North America. Thus it became important to develop a diagnostic tool that could 5 differentiate between the old and new circulating genotypes (PCV-2a and -2b, respectively). 6 Consequently, a multiplex real-time quantitative polymerase chain reaction (mrtqPCR) assay that 7 could sensitively and specifically identify and differentiate PCV-2 genotypes was developed. A 8 retrospective epidemiological survey that used the mrtqPCR assay was performed to determine if 9 cofactors could affect the risk of PCVAD. From 121 PCV-2–positive cases gathered for this 10 study, 4.13%, 92.56% and 3.31% were positive for PCV-2a, PCV-2b, and both genotypes, 11 respectively. In a data analysis using univariate logistic regressions, PCVAD compatible 12 (PCVAD/c) score was significantly associated with the presence of Porcine reproductive and 13 respiratory syndrome virus (PRRSV), PRRSV viral load, PCV-2 viral load, and PCV-2 14 immunohistochemistry (IHC) results. Polytomous logistic regression analysis revealed that 15 PCVAD/c score was affected by PCV-2 viral load (P = 0.0161) and IHC (P = 0.0128), but not by 16 the PRRSV variables (P > 0.9); suggesting that mrtqPCR in tissue is a reliable alternative to IHC. 17 Logistic regression analyses revealed that PCV-2 increased the odds ratio of isolating 2 major 18 swine pathogens of the respiratory tract, Actinobacillus pleuropneumoniae and Streptococcus 19 suis serotypes 1/2, 1, 2, 3, 4, and 7, which are serotypes commonly associated with clinical 20 diseases.
Resumo:
Los sistemas de software SIG Open Source implementados en servidores Web se encuentran en una etapa de madurez, de forma que son en muchos aspectos iguales o superiores a sus homónimos comerciales; su sofisticación, solidez, estabilidad y manejabilidad facilitan la creación de sistemas de información geográfica accesibles mediante Internet, especializados en diferentes materias, entre ellas la investigación médica. La vigilancia de la situación en salud sigue siendo la piedra angular de la detección de amenazas para la población, que requieren medidas de salud pública. La distribución de este tipo de información especializada es muy útil tanto para apoyar posteriores estudios técnicos, como para cubrir las necesidades de información de los potenciales usuarios. (...)
Resumo:
This paper presents an approach to ameliorate the reliability of the correspondence points relating two consecutive images of a sequence. The images are especially difficult to handle, since they have been acquired by a camera looking at the sea floor while carried by an underwater robot. Underwater images are usually difficult to process due to light absorption, changing image radiance and lack of well-defined features. A new approach based on gray-level region matching and selective texture analysis significantly improves the matching reliability
Resumo:
Often practical performance of analytical redundancy for fault detection and diagnosis is decreased by uncertainties prevailing not only in the system model, but also in the measurements. In this paper, the problem of fault detection is stated as a constraint satisfaction problem over continuous domains with a big number of variables and constraints. This problem can be solved using modal interval analysis and consistency techniques. Consistency techniques are then shown to be particularly efficient to check the consistency of the analytical redundancy relations (ARRs), dealing with uncertain measurements and parameters. Through the work presented in this paper, it can be observed that consistency techniques can be used to increase the performance of a robust fault detection tool, which is based on interval arithmetic. The proposed method is illustrated using a nonlinear dynamic model of a hydraulic system
Resumo:
This paper proposes a parallel architecture for estimation of the motion of an underwater robot. It is well known that image processing requires a huge amount of computation, mainly at low-level processing where the algorithms are dealing with a great number of data. In a motion estimation algorithm, correspondences between two images have to be solved at the low level. In the underwater imaging, normalised correlation can be a solution in the presence of non-uniform illumination. Due to its regular processing scheme, parallel implementation of the correspondence problem can be an adequate approach to reduce the computation time. Taking into consideration the complexity of the normalised correlation criteria, a new approach using parallel organisation of every processor from the architecture is proposed
Resumo:
In dam inspection tasks, an underwater robot has to grab images while surveying the wall meanwhile maintaining a certain distance and relative orientation. This paper proposes the use of an MSIS (mechanically scanned imaging sonar) for relative positioning of a robot with respect to the wall. An imaging sonar gathers polar image scans from which depth images (range & bearing) are generated. Depth scans are first processed to extract a line corresponding to the wall (with the Hough transform), which is then tracked by means of an EKF (Extended Kalman Filter) using a static motion model and an implicit measurement equation associating the sensed points to the candidate line. The line estimate is referenced to the robot fixed frame and represented in polar coordinates (rho&thetas) which directly corresponds to the actual distance and relative orientation of the robot with respect to the wall. The proposed system has been tested in simulation as well as in water tank conditions
Resumo:
Introducción: la tercera causa de muerte ginecológica es cáncer de ovario (CO), la detección temprana es fundamental para reducir mortalidad. El objetivo es establecer asociación entre senescencia en cultivos de tejido epitelial de ovario (ESO) mediante expresión de enzima ßgalactosidasa/normalizada y factores de riesgo reconocidos para CO. Métodos: estudio descriptivo observacional con fase exploratoria de datos proporcionados por TRF2 segunda fase; muestra 29 tejidos de mujeres con ooforectomia condiciones benignas, analizadas estadísticamente con confianza del 95%, software SPSS versión 17, datos se presentan con desviación estándar, promedio, mediana (velocidad de crecimiento celular y ßgal/Normalizada) y porcentajes (variables categóricas). Realizo comparación con t-student, test de normalidad con Shapiro Wilks y asociación mediante análisis multivariado. Resultados: encuentra evidencia estadísticamente significativa (p < 0,05) para asociación entre antecedente familiar de otros tipos de cáncer con cáncer gástrico (IC95%: -2,84, -0,23) y cáncer de seno (IC95%: -3,39, -0,38); no tener régimen de afiliación en salud (vinculado) (IC95%: -3,67 -0,014); uso de método anticonceptivo de barrera (IC95%: -3,95, -0,07); consumo de embutidos (IC95%: -3,30, -0,21) y enlatados (IC95%: -3,62, -0,030) 1 a 3 veces/semana y consumo de alcohol (IC95%: -2,33, -0,33) con aumento expresión ßgal/Normalizada. Discusión: senescencia es antitumorigénica a edades tempranas, en avanzadas es protumorigénica, cuando hay mucha acumulación de células senescentes en tejido, éstas cambian su perfil senector produciendo sustancias que afectan a las vecinas, lo que lleva a transformación tumoral. Esta investigación es novedosa.