Los usos de las nuevas tecnologías de la información y la comunicación (TIC) están transformando ... more Los usos de las nuevas tecnologías de la información y la comunicación (TIC) están transformando radicalmente las formas, los espacios y los medios de la interacción social, configurando una nueva manera de comprender la realidad. Las redes sociales y la inmensa cantidad de datos producidos por las sociedades contemporáneas son, para muchos, una nueva forma de entender “lo social” y analizar las relaciones de poder. El presente trabajo pretende analizar el uso de redes sociales y Big Data por parte de actores del poder político, principalmente en periodos de campaña electoral, así mismo, buscamos construir un andamiaje teórico que nos permita, a nosotros y futuros investigadores, analizar la relación: redes sociales, big data y comunicación política.La microsegmentación basada en big data, la Georeferenciacion,y las campañas negativas y de fake news tienen potencialidades evidentes para influir en el comportamiento electoral. Es menester, que desde el campo de la comunicación, podam...
People perceive, interpret, and assess others’ behaviors to build social ties even at young ages,... more People perceive, interpret, and assess others’ behaviors to build social ties even at young ages, affected by local contexts, which can lead, in the end, to improving learning experiences, resolving complex tasks, or creating companies. After the recent healthcare crisis due to COVID-19, online and hybrid social interactions are more prevalent in current social relationships and particularly relevant in education because information communication technologies now modulate behaviors. Here, we explore the role of social behaviors and their local contexts in building social networks and driving individual network centrality. Chilean education configuration provides a natural setting for exploring social relationships because students remain in the same group eight hours per day during their entire primary (eight years) and secondary (four years) school years. Thus, in the social mix of the classroom, students would show and witness their and others’ behaviors in both academic and socia...
La pandemia del Covid-19 alteró la forma en que se desarrollaba la educación formal, incluyendo l... more La pandemia del Covid-19 alteró la forma en que se desarrollaba la educación formal, incluyendo la Educación Física. En efecto, aquella asignatura se comenzó a desarrollar de un modo virtual. La didáctica de la Educación Física se tuvo que adaptar a aquel contexto y también los estilos de enseñanza. Por ello, se desarrolló esta investigación que tuvo por objetivo identificar los estilos de enseñanza aplicados por un grupo de profesorado chileno en sus clases con modalidad virtual. La metodología utilizada es de corte cuantitativo, con un diseño no experimental, transversal y descriptivo. La muestra del estudio corresponde a 22 docentes de Educación Física de la Región Metropolitana (17 hombres y 5 mujeres), con un rango etario entre 23 y 65 años. Para recoger los datos se ha utilizado una encuesta online aplicada en la plataforma Google Forms. Esta encuesta se enfocó en los siguientes cinco estilos de enseñanza: mando directo, enseñanza basada en la tarea, autoevaluación, enseñanza ...
Infrared Sensors, Devices, and Applications VIII, 2018
The management of fish stocks in Chile caught by small-scale fishing boats are subject to catch q... more The management of fish stocks in Chile caught by small-scale fishing boats are subject to catch quotas. Due to the massive number of fish landings, solely a very small number of landings can be inspected. In this paper, we present the first step in order to develop a vision system for automatically checking the fish quotas. This first step consists in automatically classifying the different fish species that must be checked, based upon the hypothesis that different small pelagic fish species should have different spectral signatures. Thus, we collected hyperspectral cubes, in the Near Infrared (NIR) band, for the following three species of interest: Chilean Silverside (Odontesthes regia), Southern Rays Bream (Brama australis), and Silver Hake (Merlucciidae). The hypercubes, containing 256 spectral bands in the range of 900-1700 nm, were processed and labeled to obtain the spectral signatures of the species. The spectral signatures were used to develop k-nearest neighbor and support vector machine classifiers. Their performance was compared using n-fold cross-validation and 5000 trials. When only a small subset of spectral bands was used by the classifiers, the average classification rate achieved was approximately 80%. When the entire spatial-spectral information was used, the average classification rate raised to 90%.
Bilateral adrenal hemorrhage after severe COVID-19 infection. Report of one case We report a 47-y... more Bilateral adrenal hemorrhage after severe COVID-19 infection. Report of one case We report a 47-year-old male with a severe disease caused by COVID-19, who required mechanical ventilation for 18 ays. During the hospital stay he received dexamethasone and anticoagulation with heparin. After discharge a new chest CT scan showed homogeneous hypo vascular enlargement of both adrenal glands, not present in the initial imaging studies. It was interpreted as a subacute bilateral adrenal hemorrhage. The patient remained stable and without any complaint.
Genypterus chilensis is a marine fish of high gastronomic demand, whose capture has declined in r... more Genypterus chilensis is a marine fish of high gastronomic demand, whose capture has declined in recent years due to overfishing. In the development of the farming technology, high mortalities were obtained during egg incubation. The objective of this study is to contribute to the knowledge of fecundity and eggs viability of G. chilensis in captivity. The spawns of G. chilensis were analyzed over a period of 2 years and 3 months. The total fecundity was estimated by counting the masses and eggs produced monthly throughout the period. The results confirm that G. chilensis is a partial spawner, since a female may more than two masses of eggs per day, due to a large amount of mass spawned per season (621 average). The total production of masses of the Farming Centre during the period was 2,290; of these, only 7% (166) corresponding to 15,330,517 eggs were incubated. Because of its high fecundity, G. chilensis produces numerous masses of eggs, of which only a small percentage reaches incubation, as well as it occurs in other marine fish.
The human red blood cell (RBC) membrane has significant elastic capabilities which can be describ... more The human red blood cell (RBC) membrane has significant elastic capabilities which can be described measuring typical membrane edge fluctuations and mechanical properties by optical techniques. The RBC elastic properties can be affected by changes in the surrounding media. In an attempt to elucidate the molecular mechanisms of the interaction of resveratrol with the red cell membrane and of its antioxidant capacity the changes in mechanical properties of the RBC membrane were analyzed. These studies were carried out through measurements of RBC membrane fluctuations in the presence of the oxidant agent HClO using thermal fluctuation spectroscopy (TFS). The observed results showed that the elastic capabilities of RBC changed with low concentration of hypochlorous acid but without morphological changes. However, in the presence of resveratrol the deformation and decrease of elastic capabilities induced by HClO on RBC decreased. These in vitro results demonstrated the protective effect of RV against the detrimental effects triggered by HClO upon human erythrocytes.
IEEE Colombian Conference on Communication and Computing (IEEE COLCOM 2015), 2015
Smart Grid constitutes the next generation of electricity delivery systems that intend to enhance... more Smart Grid constitutes the next generation of electricity delivery systems that intend to enhance reliability, efficiency, and security of the power grid. A fundamental component of this intelligent network is the Advanced Metering Infrastructure (AMI), which provides a two-way communication network between Utilities and a collection of smart meters located at the customers side. The interconnected meters form Neighborhood Area Networks that provide a platform for the deployment of customized AMI applications. In this paper, we study the operation of AMI in Colombia. While several Utilities are implementing first approximations to AMI that mostly focus on automated consumption readings, there is no certainty that traffic of different natures, corresponding to future AMI applications, can be supported by these initial deployments. As there is a lack of study of these issues, we carry out an extensive performance evaluation through simulations of current technologies delivering traffic from future AMI applications. Our simulations are based on an extensive review of the communication technologies that are currently employed for AMI in Colombia, and on a characterization of the future AMI applications. With our study we pursuit a better understanding of the primary challenges that will have to be faced for the development and enhancement of AMI networks in the country.
This paper presents a structural damage detection system. Variations in elasticity module are use... more This paper presents a structural damage detection system. Variations in elasticity module are used as a damage condition in a structural finite element model. This deviation alters vibration natural frequencies and shape modes; which is the fault indicator in this proposal. Noise and incomplete data are used to emulate real conditions in a beam and truss in different fault scenarios. Simulations show satisfactory performance in all cases studied. Therefore, this system can be used as suitable structural damage detection system.
Journal of Network and Computer Applications, 2015
Smart Grid is the modern infrastructure of the electric grid, which has the objective to improve ... more Smart Grid is the modern infrastructure of the electric grid, which has the objective to improve efficiency, reliability, and security. This is achieved through the control automation of the transmission and distribution lines, the enhancement of metering technologies, the implementation of renewable energy sources, and new energy management techniques. The growing demand of energy, changes in global weather, problems in the storing and distribution, and the need to implement more efficient metering systems are some of the factors that influence the transit toward a more complex and robust electric grid. A fundamental component of the Smart Grid is an Advanced Metering Infrastructure (AMI), which provides a two-way communication flow between utilities and meters at the customer side. In this survey, we outline the main features of this new infrastructure, including a classification of communication technologies and routing protocols employed in the Neighborhood Area Network domain. We introduce a set of metrics for the AMI network (such as scalability, interoperability, latency, security, and quality of service), and present a full analysis and comparison of AMI-related routing protocols and technologies. Open issues related to wireless and wired technologies, as well as routing for the neighborhood area network domain are also provided.
RESUMEN. El congrio colorado Genypterus chilensis (Guichenot, 1848) es un pez altamente demandado... more RESUMEN. El congrio colorado Genypterus chilensis (Guichenot, 1848) es un pez altamente demandado por el mercado chileno. Las capturas han disminuido y mantenido bajo 1.000 ton anuales en la década 2000-2010 con un precio de US$7 kg-1. El objetivo de este trabajo fue evaluar el crecimiento de juveniles de primera generación producida de padres silvestres en condiciones de cultivo. Se estimó el crecimiento de 128 juveniles durante cinco meses en el hatchery del CIMARQ, Valparaíso, Chile, distribuidos en cinco grupos de talla en estanques con agua marina (35 g L-1) y rango de temperatura de 12-14°C. Los pesos promedios iniciales varíaron desde el grupo menor de 4 g (11 cm) al mayor de 23 g (18 cm). Estos fueron alimentados con pellet comercial para peces marinos. Se midió mensualmente la longitud total (cm), peso (g) y se estimó sus promedios, porcentaje de crecimiento en peso, tasa de crecimiento específico, coeficiente de crecimiento termal y factor de conversión. A los cinco meses el grupo menor alcanzó un peso promedio de 16 ± 7 g (16 ± 2 cm) y el mayor 75 ± 17 g (27 ± 6 cm). Los pesos promedios mensuales se ajustaron con R 2 = 0,9 a las ecuaciones P = 3,845e 0,300t y P = 20,63e 0,240t. Los factores de conversión fluctuaron entre 8,6 y 0,3 al mes 5 para el grupo menor y de 0,6 a 0,2 para el mayor. Si se proyecta el crecimiento desde el peso inicial de 4 y 23 g hasta el peso de cosecha de 2 kg, éste se obtendría entre 26 y 18 meses para los grupos menor y mayor respectivamente. Palabras clave: Genypterus chilensis, congrio colorado, crecimiento, acuicultura, Chile. Growth of cusk eel Genypterus chilensis juveniles in culture conditions ABSTRACT. The cusk eel Genypterus chilensis (Guichenot, 1848) is a fish demanded by the Chilean market. Their catches have remained under 1,000 ton per year in the decade 2000-2010, at a price of US$7 kg-1. The aim of this study was to evaluate the growth of first generation juveniles produced by wild parents in culture conditions. Growth of 128 juveniles was estimated for five months in the hatchery of CIMARQ, Valparaiso, Chile, distributed into five size groups in tanks with seawater (35 g L-1), and temperature range: 12-14°C. Initial averages weight ranging from lower to the larger group 4 g (11 cm) to 23 g (18 cm). They were fed with commercial marine fish pellets. Total length, weight, estimated average, percentage of weight growth, specific growth rate, coefficient of thermal growth and feed conversion rate were monthly measured. The lower group at 5 months reached an average of 16 ± 7 g (16 ± 2 cm) and the largest group 75 ± 17 g (27 ± 6 cm). Their monthly average were adjusted with R 2 = 0.9 to the equations P = 3,845e 0,300t and P=20,63e 0,240t. Monthly feed conversion rates ranged from 8.6 to 0.3 at month 5 for the lower group and from 0.6 to 0.2 for the larger. Projected growth from the initial weight of 4 and 23 g to harvest weight of 2 kg could be obtained between 26 and 18 months for the smaller and larger group respectively.
The aim of this study was to evaluate the role of laparoscopic decapsulation in the management of... more The aim of this study was to evaluate the role of laparoscopic decapsulation in the management of splenic cysts. Cystic disease of spleen is an infrequent entity. Laparoscopic surgery should be considered as the method of choice for the greater of patients diagnosed with a splenic cyst. We provide 2 new cases of splenic cysts treated with partial laparoscopic decapsulation using harmonic scalpel. The patients were examined 5 years later and no cysts recurrence was found.
RESUMEN. Actualmente la tendencia de la acuicultura mundial está orientada hacia la diversificaci... more RESUMEN. Actualmente la tendencia de la acuicultura mundial está orientada hacia la diversificación de los cultivos, principalmente de especies nativas. El congrio colorado Genypterus chilensis es un pez nativo de alta demanda gastronómica y explotación estacional que lo proyecta como candidato para el desarrollo de su tecnología de cultivo. El objetivo de este trabajo fue evaluar la eficiencia de dos sistemas de incubación de masas de huevos de G. chilensis, uno con circuito cerrado de agua (SICC) y el otro con circuito abierto (SICA); su eficiencia fue medida por el porcentaje de eclosión de huevos. Dos ensayos fueron realizados midiendo y comparando los porcentajes de fecundación y eclosión de huevos en cuatro réplicas entre los dos sistemas, encontrándose solo diferencias significativas entre los porcentajes de fecundación del bioensayo 2. El bioensayo 1 tuvo un 81% promedio de fecundación de los huevos y el porcentaje promedio de eclosión para el SICC fue 42,9 ± 34,5% y para el SICA fue 0,0 ± 0,0%. El bioensayo 2 tuvo un porcentaje promedio de fecundación de los huevos de 87,3 ± 2,6% para el SICC y 79,8 ± 3,2% para el SICA y el porcentaje promedio de eclosión para el SICC fue 27,9 ± 33,7% y para el SICA fue 4,8 ± 5,6%. Se discuten los parámetros de incubación para obtener una máxima eclosión y se entrega una proposición para mejorar el sistema SICC. El sistema de incubación con circuito cerrado de agua generó mayores sobrevivencias en los huevos de G. chilensis. Palabras clave: incubación, huevos, congrio colorado, Genypterus chilensis, Chile. Evaluation and comparison of the efficiency of two incubation systems for Genypterus chilensis (Guichenot, 1848) eggs ABSTRACT. The current trend in world aquaculture is towards the diversification of cultures, mainly native species. The red cusk eel Genypterus chilensis is a native Chilean species of high gastronomic demand and seasonal exploitation that is projected as a candidate for the development of farming technology. The objective of this study was to test the efficiency of two incubation systems for G. chilensis egg masses, one with a closed water circuit (SICC) and the other with an open water circuit (SICA). Efficiency was measured by the percentage of eggs hatched. Two assays were performed, measuring and comparing the percentages of egg fecundation and hatching in four replicates between the two incubation systems. Significant differences were only found between the percentages of fecundation of bioassay 2. On average, in bioassay 1, egg fecundation reached 81%, and the average of hatching for the SICC was 42.9 ± 34.5% and for the SICA was 0.0 ± 0.0%. Bioassay 2 had an average fecundation of 87.3 ± 2.6% for the SICC and 79.8 ± 3.2% for the SICA, and the average for hatching was 27.9 ± 33.7% for the SICC and 4.8 ± 5.6% for the SICA. Incubation parameters for maximum hatching were discussed and a proposal was made for improving the SICC system. The incubation system with a closed water circuit generated greater survival of G. chilensis eggs.
Sr. Director: Hemos leído con gran interés el reciente editorial del Dr. Kehlet 1 donde hace una ... more Sr. Director: Hemos leído con gran interés el reciente editorial del Dr. Kehlet 1 donde hace una valoración de las realidades y las dificultades de la llamada fast-track surgery. Por otra parte, la colecistectomía laparoscópica (CL) es hoy día la técnica de elección para tratar ...
... Surg Endosc. 2003;17:1497. Pubmed. Rosado, Rafael a ; Gallardo, Andrés a ; Mezquita, Susana a... more ... Surg Endosc. 2003;17:1497. Pubmed. Rosado, Rafael a ; Gallardo, Andrés a ; Mezquita, Susana a ; Huertas, Francisco a ; Medina, Pedro a ; Ramírez, Diego a ; López, Javier b ; Corrales, Antonio c. a Servicio de Cirugía. Hospital de Huércal-Overa. Almería. España. ...
Los usos de las nuevas tecnologías de la información y la comunicación (TIC) están transformando ... more Los usos de las nuevas tecnologías de la información y la comunicación (TIC) están transformando radicalmente las formas, los espacios y los medios de la interacción social, configurando una nueva manera de comprender la realidad. Las redes sociales y la inmensa cantidad de datos producidos por las sociedades contemporáneas son, para muchos, una nueva forma de entender “lo social” y analizar las relaciones de poder. El presente trabajo pretende analizar el uso de redes sociales y Big Data por parte de actores del poder político, principalmente en periodos de campaña electoral, así mismo, buscamos construir un andamiaje teórico que nos permita, a nosotros y futuros investigadores, analizar la relación: redes sociales, big data y comunicación política.La microsegmentación basada en big data, la Georeferenciacion,y las campañas negativas y de fake news tienen potencialidades evidentes para influir en el comportamiento electoral. Es menester, que desde el campo de la comunicación, podam...
People perceive, interpret, and assess others’ behaviors to build social ties even at young ages,... more People perceive, interpret, and assess others’ behaviors to build social ties even at young ages, affected by local contexts, which can lead, in the end, to improving learning experiences, resolving complex tasks, or creating companies. After the recent healthcare crisis due to COVID-19, online and hybrid social interactions are more prevalent in current social relationships and particularly relevant in education because information communication technologies now modulate behaviors. Here, we explore the role of social behaviors and their local contexts in building social networks and driving individual network centrality. Chilean education configuration provides a natural setting for exploring social relationships because students remain in the same group eight hours per day during their entire primary (eight years) and secondary (four years) school years. Thus, in the social mix of the classroom, students would show and witness their and others’ behaviors in both academic and socia...
La pandemia del Covid-19 alteró la forma en que se desarrollaba la educación formal, incluyendo l... more La pandemia del Covid-19 alteró la forma en que se desarrollaba la educación formal, incluyendo la Educación Física. En efecto, aquella asignatura se comenzó a desarrollar de un modo virtual. La didáctica de la Educación Física se tuvo que adaptar a aquel contexto y también los estilos de enseñanza. Por ello, se desarrolló esta investigación que tuvo por objetivo identificar los estilos de enseñanza aplicados por un grupo de profesorado chileno en sus clases con modalidad virtual. La metodología utilizada es de corte cuantitativo, con un diseño no experimental, transversal y descriptivo. La muestra del estudio corresponde a 22 docentes de Educación Física de la Región Metropolitana (17 hombres y 5 mujeres), con un rango etario entre 23 y 65 años. Para recoger los datos se ha utilizado una encuesta online aplicada en la plataforma Google Forms. Esta encuesta se enfocó en los siguientes cinco estilos de enseñanza: mando directo, enseñanza basada en la tarea, autoevaluación, enseñanza ...
Infrared Sensors, Devices, and Applications VIII, 2018
The management of fish stocks in Chile caught by small-scale fishing boats are subject to catch q... more The management of fish stocks in Chile caught by small-scale fishing boats are subject to catch quotas. Due to the massive number of fish landings, solely a very small number of landings can be inspected. In this paper, we present the first step in order to develop a vision system for automatically checking the fish quotas. This first step consists in automatically classifying the different fish species that must be checked, based upon the hypothesis that different small pelagic fish species should have different spectral signatures. Thus, we collected hyperspectral cubes, in the Near Infrared (NIR) band, for the following three species of interest: Chilean Silverside (Odontesthes regia), Southern Rays Bream (Brama australis), and Silver Hake (Merlucciidae). The hypercubes, containing 256 spectral bands in the range of 900-1700 nm, were processed and labeled to obtain the spectral signatures of the species. The spectral signatures were used to develop k-nearest neighbor and support vector machine classifiers. Their performance was compared using n-fold cross-validation and 5000 trials. When only a small subset of spectral bands was used by the classifiers, the average classification rate achieved was approximately 80%. When the entire spatial-spectral information was used, the average classification rate raised to 90%.
Bilateral adrenal hemorrhage after severe COVID-19 infection. Report of one case We report a 47-y... more Bilateral adrenal hemorrhage after severe COVID-19 infection. Report of one case We report a 47-year-old male with a severe disease caused by COVID-19, who required mechanical ventilation for 18 ays. During the hospital stay he received dexamethasone and anticoagulation with heparin. After discharge a new chest CT scan showed homogeneous hypo vascular enlargement of both adrenal glands, not present in the initial imaging studies. It was interpreted as a subacute bilateral adrenal hemorrhage. The patient remained stable and without any complaint.
Genypterus chilensis is a marine fish of high gastronomic demand, whose capture has declined in r... more Genypterus chilensis is a marine fish of high gastronomic demand, whose capture has declined in recent years due to overfishing. In the development of the farming technology, high mortalities were obtained during egg incubation. The objective of this study is to contribute to the knowledge of fecundity and eggs viability of G. chilensis in captivity. The spawns of G. chilensis were analyzed over a period of 2 years and 3 months. The total fecundity was estimated by counting the masses and eggs produced monthly throughout the period. The results confirm that G. chilensis is a partial spawner, since a female may more than two masses of eggs per day, due to a large amount of mass spawned per season (621 average). The total production of masses of the Farming Centre during the period was 2,290; of these, only 7% (166) corresponding to 15,330,517 eggs were incubated. Because of its high fecundity, G. chilensis produces numerous masses of eggs, of which only a small percentage reaches incubation, as well as it occurs in other marine fish.
The human red blood cell (RBC) membrane has significant elastic capabilities which can be describ... more The human red blood cell (RBC) membrane has significant elastic capabilities which can be described measuring typical membrane edge fluctuations and mechanical properties by optical techniques. The RBC elastic properties can be affected by changes in the surrounding media. In an attempt to elucidate the molecular mechanisms of the interaction of resveratrol with the red cell membrane and of its antioxidant capacity the changes in mechanical properties of the RBC membrane were analyzed. These studies were carried out through measurements of RBC membrane fluctuations in the presence of the oxidant agent HClO using thermal fluctuation spectroscopy (TFS). The observed results showed that the elastic capabilities of RBC changed with low concentration of hypochlorous acid but without morphological changes. However, in the presence of resveratrol the deformation and decrease of elastic capabilities induced by HClO on RBC decreased. These in vitro results demonstrated the protective effect of RV against the detrimental effects triggered by HClO upon human erythrocytes.
IEEE Colombian Conference on Communication and Computing (IEEE COLCOM 2015), 2015
Smart Grid constitutes the next generation of electricity delivery systems that intend to enhance... more Smart Grid constitutes the next generation of electricity delivery systems that intend to enhance reliability, efficiency, and security of the power grid. A fundamental component of this intelligent network is the Advanced Metering Infrastructure (AMI), which provides a two-way communication network between Utilities and a collection of smart meters located at the customers side. The interconnected meters form Neighborhood Area Networks that provide a platform for the deployment of customized AMI applications. In this paper, we study the operation of AMI in Colombia. While several Utilities are implementing first approximations to AMI that mostly focus on automated consumption readings, there is no certainty that traffic of different natures, corresponding to future AMI applications, can be supported by these initial deployments. As there is a lack of study of these issues, we carry out an extensive performance evaluation through simulations of current technologies delivering traffic from future AMI applications. Our simulations are based on an extensive review of the communication technologies that are currently employed for AMI in Colombia, and on a characterization of the future AMI applications. With our study we pursuit a better understanding of the primary challenges that will have to be faced for the development and enhancement of AMI networks in the country.
This paper presents a structural damage detection system. Variations in elasticity module are use... more This paper presents a structural damage detection system. Variations in elasticity module are used as a damage condition in a structural finite element model. This deviation alters vibration natural frequencies and shape modes; which is the fault indicator in this proposal. Noise and incomplete data are used to emulate real conditions in a beam and truss in different fault scenarios. Simulations show satisfactory performance in all cases studied. Therefore, this system can be used as suitable structural damage detection system.
Journal of Network and Computer Applications, 2015
Smart Grid is the modern infrastructure of the electric grid, which has the objective to improve ... more Smart Grid is the modern infrastructure of the electric grid, which has the objective to improve efficiency, reliability, and security. This is achieved through the control automation of the transmission and distribution lines, the enhancement of metering technologies, the implementation of renewable energy sources, and new energy management techniques. The growing demand of energy, changes in global weather, problems in the storing and distribution, and the need to implement more efficient metering systems are some of the factors that influence the transit toward a more complex and robust electric grid. A fundamental component of the Smart Grid is an Advanced Metering Infrastructure (AMI), which provides a two-way communication flow between utilities and meters at the customer side. In this survey, we outline the main features of this new infrastructure, including a classification of communication technologies and routing protocols employed in the Neighborhood Area Network domain. We introduce a set of metrics for the AMI network (such as scalability, interoperability, latency, security, and quality of service), and present a full analysis and comparison of AMI-related routing protocols and technologies. Open issues related to wireless and wired technologies, as well as routing for the neighborhood area network domain are also provided.
RESUMEN. El congrio colorado Genypterus chilensis (Guichenot, 1848) es un pez altamente demandado... more RESUMEN. El congrio colorado Genypterus chilensis (Guichenot, 1848) es un pez altamente demandado por el mercado chileno. Las capturas han disminuido y mantenido bajo 1.000 ton anuales en la década 2000-2010 con un precio de US$7 kg-1. El objetivo de este trabajo fue evaluar el crecimiento de juveniles de primera generación producida de padres silvestres en condiciones de cultivo. Se estimó el crecimiento de 128 juveniles durante cinco meses en el hatchery del CIMARQ, Valparaíso, Chile, distribuidos en cinco grupos de talla en estanques con agua marina (35 g L-1) y rango de temperatura de 12-14°C. Los pesos promedios iniciales varíaron desde el grupo menor de 4 g (11 cm) al mayor de 23 g (18 cm). Estos fueron alimentados con pellet comercial para peces marinos. Se midió mensualmente la longitud total (cm), peso (g) y se estimó sus promedios, porcentaje de crecimiento en peso, tasa de crecimiento específico, coeficiente de crecimiento termal y factor de conversión. A los cinco meses el grupo menor alcanzó un peso promedio de 16 ± 7 g (16 ± 2 cm) y el mayor 75 ± 17 g (27 ± 6 cm). Los pesos promedios mensuales se ajustaron con R 2 = 0,9 a las ecuaciones P = 3,845e 0,300t y P = 20,63e 0,240t. Los factores de conversión fluctuaron entre 8,6 y 0,3 al mes 5 para el grupo menor y de 0,6 a 0,2 para el mayor. Si se proyecta el crecimiento desde el peso inicial de 4 y 23 g hasta el peso de cosecha de 2 kg, éste se obtendría entre 26 y 18 meses para los grupos menor y mayor respectivamente. Palabras clave: Genypterus chilensis, congrio colorado, crecimiento, acuicultura, Chile. Growth of cusk eel Genypterus chilensis juveniles in culture conditions ABSTRACT. The cusk eel Genypterus chilensis (Guichenot, 1848) is a fish demanded by the Chilean market. Their catches have remained under 1,000 ton per year in the decade 2000-2010, at a price of US$7 kg-1. The aim of this study was to evaluate the growth of first generation juveniles produced by wild parents in culture conditions. Growth of 128 juveniles was estimated for five months in the hatchery of CIMARQ, Valparaiso, Chile, distributed into five size groups in tanks with seawater (35 g L-1), and temperature range: 12-14°C. Initial averages weight ranging from lower to the larger group 4 g (11 cm) to 23 g (18 cm). They were fed with commercial marine fish pellets. Total length, weight, estimated average, percentage of weight growth, specific growth rate, coefficient of thermal growth and feed conversion rate were monthly measured. The lower group at 5 months reached an average of 16 ± 7 g (16 ± 2 cm) and the largest group 75 ± 17 g (27 ± 6 cm). Their monthly average were adjusted with R 2 = 0.9 to the equations P = 3,845e 0,300t and P=20,63e 0,240t. Monthly feed conversion rates ranged from 8.6 to 0.3 at month 5 for the lower group and from 0.6 to 0.2 for the larger. Projected growth from the initial weight of 4 and 23 g to harvest weight of 2 kg could be obtained between 26 and 18 months for the smaller and larger group respectively.
The aim of this study was to evaluate the role of laparoscopic decapsulation in the management of... more The aim of this study was to evaluate the role of laparoscopic decapsulation in the management of splenic cysts. Cystic disease of spleen is an infrequent entity. Laparoscopic surgery should be considered as the method of choice for the greater of patients diagnosed with a splenic cyst. We provide 2 new cases of splenic cysts treated with partial laparoscopic decapsulation using harmonic scalpel. The patients were examined 5 years later and no cysts recurrence was found.
RESUMEN. Actualmente la tendencia de la acuicultura mundial está orientada hacia la diversificaci... more RESUMEN. Actualmente la tendencia de la acuicultura mundial está orientada hacia la diversificación de los cultivos, principalmente de especies nativas. El congrio colorado Genypterus chilensis es un pez nativo de alta demanda gastronómica y explotación estacional que lo proyecta como candidato para el desarrollo de su tecnología de cultivo. El objetivo de este trabajo fue evaluar la eficiencia de dos sistemas de incubación de masas de huevos de G. chilensis, uno con circuito cerrado de agua (SICC) y el otro con circuito abierto (SICA); su eficiencia fue medida por el porcentaje de eclosión de huevos. Dos ensayos fueron realizados midiendo y comparando los porcentajes de fecundación y eclosión de huevos en cuatro réplicas entre los dos sistemas, encontrándose solo diferencias significativas entre los porcentajes de fecundación del bioensayo 2. El bioensayo 1 tuvo un 81% promedio de fecundación de los huevos y el porcentaje promedio de eclosión para el SICC fue 42,9 ± 34,5% y para el SICA fue 0,0 ± 0,0%. El bioensayo 2 tuvo un porcentaje promedio de fecundación de los huevos de 87,3 ± 2,6% para el SICC y 79,8 ± 3,2% para el SICA y el porcentaje promedio de eclosión para el SICC fue 27,9 ± 33,7% y para el SICA fue 4,8 ± 5,6%. Se discuten los parámetros de incubación para obtener una máxima eclosión y se entrega una proposición para mejorar el sistema SICC. El sistema de incubación con circuito cerrado de agua generó mayores sobrevivencias en los huevos de G. chilensis. Palabras clave: incubación, huevos, congrio colorado, Genypterus chilensis, Chile. Evaluation and comparison of the efficiency of two incubation systems for Genypterus chilensis (Guichenot, 1848) eggs ABSTRACT. The current trend in world aquaculture is towards the diversification of cultures, mainly native species. The red cusk eel Genypterus chilensis is a native Chilean species of high gastronomic demand and seasonal exploitation that is projected as a candidate for the development of farming technology. The objective of this study was to test the efficiency of two incubation systems for G. chilensis egg masses, one with a closed water circuit (SICC) and the other with an open water circuit (SICA). Efficiency was measured by the percentage of eggs hatched. Two assays were performed, measuring and comparing the percentages of egg fecundation and hatching in four replicates between the two incubation systems. Significant differences were only found between the percentages of fecundation of bioassay 2. On average, in bioassay 1, egg fecundation reached 81%, and the average of hatching for the SICC was 42.9 ± 34.5% and for the SICA was 0.0 ± 0.0%. Bioassay 2 had an average fecundation of 87.3 ± 2.6% for the SICC and 79.8 ± 3.2% for the SICA, and the average for hatching was 27.9 ± 33.7% for the SICC and 4.8 ± 5.6% for the SICA. Incubation parameters for maximum hatching were discussed and a proposal was made for improving the SICC system. The incubation system with a closed water circuit generated greater survival of G. chilensis eggs.
Sr. Director: Hemos leído con gran interés el reciente editorial del Dr. Kehlet 1 donde hace una ... more Sr. Director: Hemos leído con gran interés el reciente editorial del Dr. Kehlet 1 donde hace una valoración de las realidades y las dificultades de la llamada fast-track surgery. Por otra parte, la colecistectomía laparoscópica (CL) es hoy día la técnica de elección para tratar ...
... Surg Endosc. 2003;17:1497. Pubmed. Rosado, Rafael a ; Gallardo, Andrés a ; Mezquita, Susana a... more ... Surg Endosc. 2003;17:1497. Pubmed. Rosado, Rafael a ; Gallardo, Andrés a ; Mezquita, Susana a ; Huertas, Francisco a ; Medina, Pedro a ; Ramírez, Diego a ; López, Javier b ; Corrales, Antonio c. a Servicio de Cirugía. Hospital de Huércal-Overa. Almería. España. ...
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