Optimization of the Digital Terrestrial Television Transmission Mode of DVB-T2 in Colombia

In December 2011, Colombia updated its national Digital Terrestrial Television (DTT) standard from DVB-T to DVB-T2, the second generation of the DVB (Digital Video Broadcasting) project. DVB-T2 is the current state-of-the art DTT system in the world, and it brings very significant improvements in terms of capacity, bustness and flexibility compared with its predecessor. The case of Colombia is very special because it was the first country to deploy DVB-T2 with 6 MHz channelization and because the DVB-T2 networks were deployed from scratch without any constraint mposed by existing DVB-T infrastructure. This paper analyzes potential DVB-T2 ransmission modes to optimize existing DTT network designs of Colombia, originally made for DVB-T, analyzing the trade-offs between capacity, coverage level and ingle Frequency Network (SFN) size. Network planning results has been performed with a professional DTT networkplanning tool based on the three first deployment hases of the DTT network of the public national TV broadcaster RTVC.Results btained fully justify the decision of adopting DVB-T2. Compared with the initial DVB-T design, DVB-T2 can increase the national covered population up to 7.3% or offer 70.2% more of capacity transmission, or increase the SFN size up to 135% keeping the total power transmission and the geographic distribution of the transmitters.Martínez Pinzón, G.; López Sánchez, J.; Gómez Barquero, D.; Cardona Marcet, N. (2015). Optimization of the Digital Terrestrial Television Transmission Mode of DVB-T2 in Colombia. IEEE Latin America Transactions. 13(7):2144-2151. doi:10.1109/TLA.2015.7273770S2144215113

Targeted Next-Generation Sequencing of Congenital Hypothyroidism-causative Genes Reveals Unexpected Thyroglobulin Gene Variants in Patients with Iodide Transport Defect

Congenital iodide transport defect is an uncommon autosomal recessive disorder caused by loss-of-function variants in the sodium iodide symporter (NIS)-coding SLC5A5 gene and leading to dyshormonogenic congenital hypothyroidism. Here, we conducted a targeted next-generation sequencing assessment of congenital hypothyroidism-causative genes in a cohort of nine unrelated pediatric patients suspected of having a congenital iodide transport defect based on the absence of 99mTc-pertechnetate accumulation in a eutopic thyroid gland. Although, unexpectedly, we could not detect pathogenic SLC5A5 gene variants, we identified two novel compound heterozygous TG gene variants (p.Q29* and c.177-2A\u3eC), three novel heterozygous TG gene variants (p.F1542Vfs*20, p.Y2563C, and p.S523P), and a novel heterozygous DUOX2 gene variant (p.E1496Dfs*51). Splicing minigene reporter-based in vitro assays revealed that the variant c.177-2A\u3eC affected normal TG pre-mRNA splicing, leading to the frameshift variant p.T59Sfs*17. The frameshift TG variants p.T59Sfs*17 and p.F1542Vfs*20, but not the DUOX2 variant p.E1496Dfs*51, were predicted to undergo nonsense-mediated decay. Moreover, functional in vitro expression assays revealed that the variant p.Y2563C reduced the secretion of the TG protein. Our investigation revealed unexpected findings regarding the genetics of congenital iodide transport defects, supporting the existence of yet to be discovered mechanisms involved in thyroid hormonogenesis

Brucella neotomae Infection in Humans, Costa Rica

Several species of Brucella are known to be zoonotic, but B. neotomae infection has been thought to be limited to wood rats. In 2008 and 2011, however, B. neotomae was isolated from cerebrospinal fluid of 2 men with neurobrucellosis. The nonzoonotic status of B. neotomae should be reassessed

Vibrio mimicus diarrhea following ingestion of raw turtle eggs

artículo (arbitrado) -- Universidad de Costa Rica. Centro de Investigaciones en Biología Celular y Molecular, 1996Clinical and epidemiological characteristics of diarrhea associated with Vibrio mimicus were identified in 33 hospitalized patients referred to the Costa Rican National Diagnostic Laboratory Network between 1991 and 1994. The relevant symptoms presented by patients included abundant watery diarrhea, vomiting, and severe dehydration that required intravenous Dhaka solution in 83% of patients but not fever. Seroconversion against V. mimicus was demonstrated in four patients, from whom acute- and convalescent-phase sera were obtained. Those sera did not show cross-reaction when tested against Vibrio cholerae O1 strain VC-12. All the V. mimicus isolates from these cases produced cholera toxin (CT) and were susceptible to commonly used antibiotics. Attempts to isolate this bacterium from stool samples of 127 healthy persons were not successful. Consumption of raw turtle eggs was recalled by 11 of the 19 (58%) individuals interviewed. All but two V. mimicus diarrheal cases were sporadic. These two had a history of a common source of turtle (Lepidochelys olivacea) eggs for consumption, and V. mimicuswas isolated from eggs from the same source (a local market). Among the strains, variations in the antimicrobial susceptibility pattern were observed. None of the strains recovered from market turtle eggs nor the four isolates from river water showed CT production. Further efforts to demonstrate the presence of CT-producing V. mimicus strains in turtle eggs were made. Successful results were obtained when nest eggs were tested. In this case, it was possible to isolate CT- and non-CT-producing strains, even from the same egg. For CT detection we used PCR, enzyme-linked immunosorbent assay (ELISA), and Y-1 cell assay, obtaining a 100% correlation between ELISA and PCR results. Primers Col-1 and Col-2, originally described as specific for the V. cholerae O1 ctxA gene, also amplified a 302-bp segment with an identical restriction map from V. mimicus. These results have important implications for epidemiological surveillance in tropical countries where turtle eggs are used for human consumption, serving as potential sources of cholera-like diarrhea.Universidad de Costa RicaUCR::Vicerrectoría de Investigación::Unidades de Investigación::Ciencias Básicas::Centro de Investigación en Biología Celular y Molecular (CIBCM

Frequency and Network Planning and Optimization of the Digital Terrestrial Television DVB-T2 Networks in Colombia

[EN] In December 2011, Colombia updated its national Digital Terrestrial Television (DTT) standard from DVB-T to DVBT2, the second-generation European DTT standard. DVBT2 is the current state-of-the art DTT system in the world, and it brings very significant improvements in terms of capacity, robustness and flexibility compared with any other DTT technology. The iTEAM Research Institute was very involved in the promotion and adoption of DVB-T2 in Colombia. The case of Colombia is unique because it was the first country to deploy DVB-T2 with 6 MHz channelization, and because the digital networks will co-exist with the analogue NTSC network until the analogue switch-off and with digital ISDB-Tb and DVB-T networks in the neighbor countries. Furthermore, DVB-T2 networks will be deployed from scratch without any constraint imposed by existing DVB-T infrastructure. This paper provides an overview of the frequency and network DVB-T2 planning activities performed by the iTEAM Research Institute in cooperation with the Spectrum Regulator of Colombia.This work was partially supported by the Spectrum Regulator of Colombia ANE (Agencia Nacional del Espectro). The authors thank the Spanish companies Ingenia-Telecom and Axión Infraestructuras de Telecomunicación, partners in some of the projects developed for the ANE.Gómez Barquero, D.; López Sánchez, J.; Martinez Pinzon, G.; Ribadeneira Ramírez, JA.; Garro Crevillen, E.; García Pardo, C.; Fuentes Muela, M.... (2014). Frequency and Network Planning and Optimization of the Digital Terrestrial Television DVB-T2 Networks in Colombia. Waves. 6:35-49. http://hdl.handle.net/10251/56485S3549

High efficiency wireless video networks for next generation of ENG services

This work has been partially funded by the CDTI under the FREEDOM (Servicios de Videocomunicaciones de Alta Eficiencia para Redes Inalámbricas de Nueva Generación en Movilidad) project, with Reference Number IDI20120486.Ruiz, D.; Giménez Gandia, JJ.; Gómez Barquero, D.; Anaya, JJ.; Fernández, FJ.; Valdés Francisco J.; Barjau, C.... (2013). High efficiency wireless video networks for next generation of ENG services. Waves. 5-16. http://hdl.handle.net/10251/55008S51

AGRICULTURAL CREDIT IN COSTA RICA: DIAGNOSIS AND RECOMMENDATIONS

Although credit can be directed with sufficient facility toward some economic activities, the same cannot be said about agriculture, first because there are thousands of clients and secondly, most of them do not meet the requirements for obtaining a loan. Moreover, they do not know how to utilize credit and frequently they do not accept the general conditions that the credit institutions establish. Unfamiliarity with the sources of funds is another problem. Therefore, if credit does not accompany other complementary services, like technical assistance for example, the farmers present low modernization indexes, and productivity levels are not very different in relation to those who do not use credit. Given the importance that agricultural credit has for the Costa Rican economy and its role in the country's development, it is necessary to examine the agricultural credit situation with emphasis on the last eight years. For this reason the method of analysis employed in this study is descriptive and diagnostic

AGRICULTURAL CREDIT IN COSTA RICA: DIAGNOSIS AND RECOMMENDATIONS

Although credit can be directed with sufficient facility toward some economic activities, the same cannot be said about agriculture, first because there are thousands of clients and secondly, most of them do not meet the requirements for obtaining a loan. Moreover, they do not know how to utilize credit and frequently they do not accept the general conditions that the credit institutions establish. Unfamiliarity with the sources of funds is another problem. Therefore, if credit does not accompany other complementary services, like technical assistance for example, the farmers present low modernization indexes, and productivity levels are not very different in relation to those who do not use credit. Given the importance that agricultural credit has for the Costa Rican economy and its role in the country's development, it is necessary to examine the agricultural credit situation with emphasis on the last eight years. For this reason the method of analysis employed in this study is descriptive and diagnostic.Agricultural Finance,

Efecto de ocho clases de expresión corporal en el estado de ánimo y autoconcepto general de jóvenes universitarios

The purpose of this study was to investigate the psychological effects of body expression in students from the University of Costa Rica. Thirty-five young people from two groups: 17 from Theater Workshop and 18 from Theater Appreciation. Average age: men 18.78 ± 1.42 and 18.52 ± 1.91 age women. The first subjects performed eight corporal expression sessions of two hours once a week for eight weeks. The second subjects received eight lectures on theater appreciation, two hours once a week for eight weeks. The measurements of mood were made using the profile of mood states (POMS) pre and post the first, fourth and eighth session. Measurements of self-concept were conducted prior to the commencement of the first session (Pre), at the end of the fourth session (Test), and at the end of the eighth session (Post-test). There were significant improvements in mood states of tension and vigor and in the variable of inhibition-empathy-distrust. It is concluded that the body expression can have a positive impact on moods and self-concept of college students during their first semester on University.El propósito del estudio fue indagar sobre los efectos psicológicos de la expresión corporal en estudiantes de la Universidad de Costa Rica. Se trabajó con 35 jóvenes de dos grupos: 17 de taller de teatro y 18 de apreciación de teatro. Su promedio de edad: hombres 18,78 ± 1,42 y mujeres 18,52 ± 1,91 años. Los sujetos de taller realizaron ocho sesiones de expresión corporal de dos horas, una vez por semana por ocho semanas. Los sujetos de apreciación recibieron ocho clases magistrales sobre teatro, de dos horas, una vez por semana por ocho semanas. Las mediciones del estado de ánimo se realizaron por medio del perfil de estados de ánimo (P.O.M.S.) pre y post de la primera, la cuarta y octava sesión. Las mediciones del autoconcepto general se realizaron previo al inicio de la primera sesión (Pre), al final de la cuarta sesión (Test), y al final de la octava sesión (Post-test). Como resultados se encontraron mejoras significativas en los estados de ánimo de tensión y vigor, así como en la variable de inhibición-empatía-desconfianza. Se concluye que la expresión corporal puede influir positivamente sobre estados de ánimo y el autoconcepto de estudiantes de nivel universitario, durante su primer ciclo en la Universidad

Análisis de las Posibilidades de Conectividad Existentes en Centroamérica, para el Establecimiento de una Red de Comunicaciones

Obando Barquero, M. & Hernández Granda, G. (1998). Análisis de las Posibilidades de Conectividad Existentes en Centroamérica, para el Establecimiento de una Red de Comunicaciones. [Tesis de Licenciatura]. Universidad Nacional, Costa Rica.El contenido de este trabajo está estructurado según el esquema de procedimientos o pasos apropiados, que recomienda el autor Arellano en su libro Elementos de investigación, con el objetivo de determinar las posibles formas de comunicación que se pueden presentar en Centroamérica apoyadas éstas sobre las infraestructuras de telecomunicaciones centroamericanas, que permiten la transmisión de datos, voz e imagen en movimiento (videoconferencia). El documento producto de nuestra investigación se esquematiza de la siguiente manera: El primer capítulo denominado introducción contempla los antecedentes y justificaciones que se dieron para llevar a cabo este trabajo, así como la formulación del problema presentado y que nos indujo a la investigación. El segundo capítulo corresponde al Marco Teórico y presenta toda la información generalizada sobre elementos que sustentan los resultados. El capítulo tercero Recolección de datos, describe la definición de las variables a investigar y evaluar, así como la metodología empleada para llevar a acabo esta investigación, los instrumentos que se usaron para recoger la información y las fuentes de donde ésta fue tomada. El capítulo cuarto denominado Presentación y Análisis de Datos, nos permite mostrar todos los datos producto de nuestra investigación, en forma esquematizada según los tópicos orientados por las diferentes variables definidas en el capítulo cuarto. El capítulo quinto Conclusiones, nos permite ofrecer las conclusiones que se lograron con la investigación y que son el producto final importante de este trabajo y en las cuales afirmamos cuál o cuales son los problemas o situaciones que se dan en el área cuando se busca la implementación de una red a nivel centroamericano que involucre datos, voz y videoconferencia.Universidad Nacional, Costa RicaEscuela de Informátic