Optimal estimation for discrete time jump processes

Optimum estimates of nonobservable random variables or random processes which influence the rate functions of a discrete time jump process (DTJP) are obtained. The approach is based on the a posteriori probability of a nonobservable event expressed in terms of the a priori probability of that event and of the sample function probability of the DTJP. A general representation for optimum estimates and recursive equations for minimum mean squared error (MMSE) estimates are obtained. MMSE estimates are nonlinear functions of the observations. The problem of estimating the rate of a DTJP when the rate is a random variable with a probability density function of the form cx super K (l-x) super m and show that the MMSE estimates are linear in this case. This class of density functions explains why there are insignificant differences between optimum unconstrained and linear MMSE estimates in a variety of problems

Characterization of the Physical - Mechanical Properties of Alpaca Fiber (Vicugna Pacos) at the Tunshi Experimental Station

The alpaca is one of the four South American camelids that mainly inhabit the inter-Andean zone of Ecuador. Alpaca fiber is characterized by being a natural, soft and resistant fiber, of which, the fleece is the most valued part. The objective of this research was to evaluate the quality parameters of alpaca fiber in terms of physical-mechanical properties. The research was carried out in the Tunishi Experimental Station, ESPOCH. A descriptive statistic of mean, minimum and maximum range, and separation of means per student was applied. The alpaca with characteristics of Huacaya breed was selected and the shearing was carried out manually to obtain the fleece. Later, the performance of the fleece was evaluated, which was 85.71%. Two categories of fiber were selected: fine and thick. Sixty samples were taken for analysis by stretched and unstretched fiber length. The measurements of unstretched fiber length in cm for the thin and thick fiber were 12.50 cm and 13.52 cm respectively, presenting significant differences (p≤0.05). The measurements of the stretched fiber length in cm were 17.29 cm for fine fiber and 17.27 cm for thick fiber, presenting no significant differences (p≥0.05). The resistance of thread and fabric for fine fiber was 590 N/cm2, and for thick fiber was 2835.5 N/cm2, presenting highly significant differences (p≤0.01). Regarding the percentage of yarn elongation, the values obtained were 19% for fine fiber and 12% for thick fiber, observing highly significant differences (p≤0.01). The thick fiber fabric had a better resistance (2.3 BAR) than the fine fiber fabric (1.7 BAR), with a time of 2.34 s and 1.88 s respectively. The classification of the fiber by its softness did not present significant differences. Finally, regarding the sensory classification, it was established as a soft fiber with 91%. Keywords: alpaca, fleece, fine fiber, thick fiber, fiber properties. Resumen La alpaca es uno de los cuatro camélidos sudamericanos que principalmente habitan en la zona interandina del Ecuador. La fibra de alpaca se caracteriza por ser una fibra natural, suave y resistente; de la cual, el vellón es la parte de la fibra del animal más valorada. El objetivo de esta investigación fue evaluar los parámetros de calidad de fibra de alpaca en cuanto a las propiedades físico - mecánicas. La investigación se la realizó en la Estación Experimental TUNSHI - ESPOCH. Se aplicó una estadística descriptiva de media, rango mínimo y máximo y separación de medias por t estudent. Se seleccionó a la alpaca con características de la raza Huacaya y se realizó la esquila por el método manual para la obtención del vellón. Posteriormente, se evaluó el rendimiento del vellón el cual fue de 85,71%, se seleccionaron dos categorías de fibra fina y gruesa. Sesenta muestras fueron tomadas para su análisis: longitud de mecha estirada y sin estirar. La media de longitud de fibra sin estirar en cm para la fina y gruesa fueron de 12,50 y 13,52 correspondientemente, presentando diferencias significativas (p≤0,05), La media de la longitud en cm de fibra estirada determinó que la fibra fina presentó una media de 17,29 y la fibra gruesa de 17,27 cm, sin presentar diferencias significativas (p≥0,05). La resistencia del hilo y tejido para la fibra fina fue de 590 N/cm2 y para la gruesa fue de 2835,5 N/cm2, presentando diferencias altamente significativas (p≤0,01). Finalmente, en cuanto al porcentaje de elongación de hilo, presentó un 19% para fibra fina y un 12% para gruesa, observándose también diferencias altamente significativas (p≤0,01). El tejido de la fibra gruesa tuvo mejor resistencia (2,3 BAR) que el de la fibra fina (1,7 BAR), con un tiempo de 2,34 s y 1,88 s respectivamente. La clasificación de la fibra por su suavidad, no presentó diferencias significativas. En cuanto a la clasificación sensorial se la ubico como una fibra suave con el 91%. Palabras clave: alpaca, vellón, fibra fina, fibra gruesa, propiedades de la fibra

Soil-transmitted helminth parasites and allergy: Observations from Ecuador.

There is considerable interest as to potential protective effects of soil-transmitted helminths (STH) against allergy and allergic diseases. Here, we discuss findings of studies done of the effects of STH parasites on atopy and allergic diseases in Ecuador. While cross-sectional studies have consistently shown a reduced prevalence of allergen skin prick test (SPT) reactivity among infected schoolchildren, the removal of these infections by repeated deworming did not affect SPT prevalence over the short-term (ie, 12 months) but may have increased SPT prevalence over the long-term (ie, 15-17 years). In the case of allergic symptoms, cross-sectional studies have generally not shown associations with STH and intervention studies showed no impact on prevalence. However, a birth cohort suggested that early STH infections might reduce wheeze by 5 years. Allergic sensitization to Ascaris, however, explained a significant proportion of wheezing among rural schoolchildren. Studies of the effects of STH on immune and inflammatory responses indicated a potential role of STH in contributing to more robust regulation. The effects of STH on allergy are likely to be determined by history of exposure over the life-course and by interactions with a wide variety of other infectious and non-infectious factors

Persistencia de vena cava superior izquierda: ¿marcador ecocardiográfico de malformaciones fetales cardiacas y extra-cardiacas

Introduction: Persistentleft upper vena cava (VSIP) is the most common congenital vascular malformation, observed in 0.3% of autopsies in the general population and 4-8 % of patients with congenital heart disease. During early embryological development the venous return of the head and arms normally drains into the right atrium by the left and right upper cardinal veins. Objective: Relate the Persistence of Vena Cava Superior Left (VCSIP) diagnosed by fetal echocardiographic study, with the presence of intraandal abnormalities. Methodology: A descriptive, retrospective study is carried out in 75 cases obtained from the database of the Department of Perinatal Medicine of the Hospital Universitario La Paz (Madrid –Spain), during the period between 2006 -2017 with prenatal diagnosis of (VCSIP). Echocardiographic studies at 32 amniocentesis and 2 chorionic rate biopsies are performed onall 75 patients and, whether or not, related to congenital cardiac abnormalities and extracardiac defects are established. Statistical analysis is performed using the STATA program. Result: 75 fetuses diagnosed with VcSIP were ultrasoundd, with an averagegestational age at diagnosis of 26.6 weeks (DE: 5.87; IC: 95%). In 14 patients (18.67%) no malformations were detected; 27 patients (36%) cardiac abnormalities were evident; 15 patients (20%), had extra cardiac malformations and 19 patients (25.33%), had extra and intracardiac malformations. Conclusions: Prenatal ultrasound has a major impact for early diagnosisof anatomical effects and variations such as the upper left vena cava. Diagnosis of this alteration requires desperation and monitoring of other associated foetal abnormalities, whether intra and extra-cardiac. With good prenatal ultrasound screening it would not be imperative to indicate to patients with isolated VcSIP an invasive prenatal test.Introducción:Lavena cava superior izquierda persistente(VCSIP) es la malformación vascular congénita más frecuente, observada en el 0.3% de autopsias en la población general y en el 4 -8 % de pacientes con cardiopatías congénitas. Durante el desarrollo embriológico temprano el retorno venoso de la cabeza y los brazos normalmente drena en la aurícula derecha por las venas cardinales anteriores izquierda y derecha. Objetivo: Relacionar la Persistencia de Vena Cava Superior Izquierda (VCSIP) diagnosticada por estudio ecocardiográfico fetal, con la presencia de anomalías intra y extracardiacas. Metodología: Se realiza un estudio descriptivo, retrospectivo en 75 casos obtenidos de la base de datos del departamento de Medicina Perinatal del Hospital Universitario La Paz (Madrid –España), durante el periodo comprendido entre 2006 -2017 con diagnóstico prenatal de (VCSIP). A los 75 pacientes se realiza estudio ecocardiográfico, a 32 amniocentesis y a 2 biopsia de velocidades coriónicas y, se establece su relación o no, con anomalías congénitas cardiacas y extracardiacas. El análisis estadístico se realiza mediante el programa STATA. Resultados: Se analizaron ecográficamente 75 fetos con diagnóstico de VCSIP, con una media de edad gestacional al diagnóstico de 26,6 semanas (DE:5,87; IC: 95%). En 14 pacientes (18.67%)no se detectaron malformaciones; en 27 pacientes (36%) se evidenciaron alteraciones cardiacas; 15 pacientes (20%), presentaron malformaciones extra cardiacas y 19 pacientes (25.33%), presentaron malformaciones extra e intracardiacas. Conclusiones: La ecografía prenatal tiene un gran impacto para el diagnóstico temprano de afectaciones y variaciones anatómicas como la vena cava superior izquierda. El diagnóstico de esta alteración obliga a realizar despistaje y seguimiento de otras anomalías fetales asociadas ya sean intra y extra-cardiacas. Con un buen screening ecográfico prenatal no sería imperativo indicar a los pacientes con VCSIP aislada una prueba invasiva prenatal

Persistencia de vena cava superior izquierda: ¿marcador ecocardiográfico de malformaciones fetales cardiacas y extra-cardiacas

Introduction: Persistentleft upper vena cava (VSIP) is the most common congenital vascular malformation, observed in 0.3% of autopsies in the general population and 4-8 % of patients with congenital heart disease. During early embryological development the venous return of the head and arms normally drains into the right atrium by the left and right upper cardinal veins. Objective: Relate the Persistence of Vena Cava Superior Left (VCSIP) diagnosed by fetal echocardiographic study, with the presence of intraandal abnormalities. Methodology: A descriptive, retrospective study is carried out in 75 cases obtained from the database of the Department of Perinatal Medicine of the Hospital Universitario La Paz (Madrid –Spain), during the period between 2006 -2017 with prenatal diagnosis of (VCSIP). Echocardiographic studies at 32 amniocentesis and 2 chorionic rate biopsies are performed onall 75 patients and, whether or not, related to congenital cardiac abnormalities and extracardiac defects are established. Statistical analysis is performed using the STATA program. Result: 75 fetuses diagnosed with VcSIP were ultrasoundd, with an averagegestational age at diagnosis of 26.6 weeks (DE: 5.87; IC: 95%). In 14 patients (18.67%) no malformations were detected; 27 patients (36%) cardiac abnormalities were evident; 15 patients (20%), had extra cardiac malformations and 19 patients (25.33%), had extra and intracardiac malformations. Conclusions: Prenatal ultrasound has a major impact for early diagnosisof anatomical effects and variations such as the upper left vena cava. Diagnosis of this alteration requires desperation and monitoring of other associated foetal abnormalities, whether intra and extra-cardiac. With good prenatal ultrasound screening it would not be imperative to indicate to patients with isolated VcSIP an invasive prenatal test.Introducción:Lavena cava superior izquierda persistente(VCSIP) es la malformación vascular congénita más frecuente, observada en el 0.3% de autopsias en la población general y en el 4 -8 % de pacientes con cardiopatías congénitas. Durante el desarrollo embriológico temprano el retorno venoso de la cabeza y los brazos normalmente drena en la aurícula derecha por las venas cardinales anteriores izquierda y derecha. Objetivo: Relacionar la Persistencia de Vena Cava Superior Izquierda (VCSIP) diagnosticada por estudio ecocardiográfico fetal, con la presencia de anomalías intra y extracardiacas. Metodología: Se realiza un estudio descriptivo, retrospectivo en 75 casos obtenidos de la base de datos del departamento de Medicina Perinatal del Hospital Universitario La Paz (Madrid –España), durante el periodo comprendido entre 2006 -2017 con diagnóstico prenatal de (VCSIP). A los 75 pacientes se realiza estudio ecocardiográfico, a 32 amniocentesis y a 2 biopsia de velocidades coriónicas y, se establece su relación o no, con anomalías congénitas cardiacas y extracardiacas. El análisis estadístico se realiza mediante el programa STATA. Resultados: Se analizaron ecográficamente 75 fetos con diagnóstico de VCSIP, con una media de edad gestacional al diagnóstico de 26,6 semanas (DE:5,87; IC: 95%). En 14 pacientes (18.67%)no se detectaron malformaciones; en 27 pacientes (36%) se evidenciaron alteraciones cardiacas; 15 pacientes (20%), presentaron malformaciones extra cardiacas y 19 pacientes (25.33%), presentaron malformaciones extra e intracardiacas. Conclusiones: La ecografía prenatal tiene un gran impacto para el diagnóstico temprano de afectaciones y variaciones anatómicas como la vena cava superior izquierda. El diagnóstico de esta alteración obliga a realizar despistaje y seguimiento de otras anomalías fetales asociadas ya sean intra y extra-cardiacas. Con un buen screening ecográfico prenatal no sería imperativo indicar a los pacientes con VCSIP aislada una prueba invasiva prenatal

NIRS potential use for the determination of natural resources quality from dehesa (acorn and grass) in Montanera system for Iberian pigs.

NIRS technology has been used as an alternative to conventional methods to determinate the content of nutrients of acorns and grass from dehesa ecosystem. Dry matter (DM), crude fat (CF), crude protein (CP), starch, total phenolic compounds (TP), α-tocopherol, γ-tocopherol, fatty acids, neutral detergent fiber (NDF), total antioxidant activity (TAA) and total energy (TE) were determined by conventional methods for later development of NIRS predictive equations. The NIR spectrum of each sample was collected and for all studied parameters, a predictive model was obtained and external validated. Good prediction equations were obtained for moisture, crude fat, crude protein, total energy and γ-tocopherol in acorns samples, with high coefficients of correlation (1-VR) and low standard error of prediction (SEP) (1-VR=0.81, SEP=2.62; 1-VR=0.92, SEP=0.54; 1-VR=0.86, SEP=0.47; 1-VR=0.84, SEP=0.2; 1-VR=0.88, SEP=5.4, respectively) and crude protein, NDF, α-tocopherol and linolenic acid content in grass samples (1-VR=0.9, SEP=1.99; 1-VR=0.87, SEP=4.13; 1-VR=0.76, SEP=10.9; 1-VR=0.82, SEP=0.6, respectively). Therefore, these prediction models could be used to determinate the nutritional composition of Montanera natural resources

Instructional Design Methodological Proposal for the Training of Online Content Tutors

With the challenge of change that a teacher faces, the use of educational technologies requires knowledge of instructional design. The teacher plays a prominent role in this process, so it must create educational content, following the principles of an instructional design model. The problem is that not all methodologies include a practical approach where the tutor takes ownership of pedagogical and practical aspects. Therefore, this study proposes an instructional design methodology for online Tutors combining the ADDIE, ASSURE, and PACIE models. In addition, to validate the proposed methodology, an evaluation process is carried out, taking into account the appropriation of the role of tutor of online content and level of use of the LMS tools.     Keywords: instructional design, LMS, online course, E-learnin

Temperament and welfare. Effect on production of cattle meat

Los bovinos con temperamento indócil ganan menos peso, producen carne mas dura, y presentan pérdidas por hematomas y abscesos en distintas áreas musculares, adquiridas durante el manejo y el transporte que deben eliminarse para comercializar. Las perdidas en argentina se estiman en 0,89 u$s por animal faenado siendo de 28 y 47 dólares para Estados Unidos, aumentando la preocupación por el bienestar de los animales. El temperamento se define como el conjunto de comportamientos de los animales relacionados con el hombre atribuido al miedo. Los test que miden temperamento evalúan el miedo, imitando condiciones peligrosas con las que se encuentran los animales en su ambiente de producción, para estandarizar la reactividad entre individuos. Algunos test restringen físicamente a los animales para evaluar su comportamiento, otros observan los animales en áreas grandes incluyendo interacción con el operador. Existen indicios de que es posible modificar la intensidad de las reacciones emocionales por manejo y selección, amansando los animales mediante procesos de habituación y de aprendizaje asociativo. Las medidas del temperamento tuvieron moderada a alta heredabilidad (h2= 0,54) cuando los test se realizaron al destete y baja (h2= 0,26) cuando se evaluaron nuevamente a los 18 meses de edad. Siendo el temperamento un carácter heredable que impacta sobre el bienestar animal y la producción bovina, el mismo puede utilizarse como criterio de selección. La selección por temperamento requerirá establecer un sistema de evaluación estandarizado e implementar buenas prácticas de manejo para reducir las perdidas económicas.The bovine ones which have unruly temperament gain less weight produce firm meat, and present losses for bruises and abscesses in different muscular areas acquired during the managing and the transport that must be eliminated to commercialize. The losses in Argentine are estimated in 0,89 u$s by slaughtered animal being 28 and 47 dollars for The United States, increasing the worry for the welfare of the animals. The temperament is defined as the set of behaviors of the animals related to the man attributed to fear. The tests that measure temperament evaluate fear, imitating hazardous conditions which find the animals in their production environment, to standardize the reactivity among individuals. Some tests restrict animals physically; others observe the animals in big areas including interaction with the operator. There are evidences which indicate that it is possible to modify the intensity of the emotional reactions for managing and selection, taming the animals by means of processes of habituation and of associative learning. Temperament measures were moderate heritability (h2 = 0,54) when the test carried out to the weaning and fell (h2 = 0,26) when they were evaluated again at 18 months of age. Being the temperament a character inheritable that strikes on the animal well-being and the bovine production, it can be used as criterion of selection. The selection for temperament will need to establish a standardized evaluation system and to implement good managing practices to reduce economic losses.Facultad de Ciencias Veterinaria