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Robust coordination of overcurrent and undervoltage protection devices for microgrids
(2018-12-30) Núñez Mata, Óscar Fernando; Palma Behnke, Rodrigo; Mendoza Araya, Patricio
The development of a proper protection system is essential for the secure and reliable operation of microgrids. In a microgrid, operating conditions that produce limited magnitudes of fault currents will be insufficient to activate the overcurrent protective devices. Therefore, it will be necessary to propose new protection systems for its safe and reliable operation. In this work, a new methodology for optimal coordination of protection devices based in a robust optimization is proposed. This proposal uses a protective device based on the combined action of overcurrent and undervoltage elements, which are operating in an interleaved manner. Internal time coordination of both protection elements is required. Once the overcurrent element is established as the primary protection, and the undervoltage element as the backup protection, the operating times of the protective devices are optimized. The methodology was evaluated in the ESUSCON microgrid, which is a low-voltage isolated microgrid located in northern Chile. The simulation results show a better performance of the proposed device than the existing protection system of the microgrid. The proposed methodology proved its effectiveness by clearing all evaluated faults in a timely and coordinated manner.
El grupo genérico Hoodothrips (Terebrantia: Heliothripidae)
(Acta zoológica, 2007) Retana Salazar, Axel Pedro
En este trabajo se presenta el análisis filogenético del grupo genérico Hoodothrips. Varios caracteres sinapomórficos se incluyen para la determinación del grupo Hoodothrips, el cual es descrito como la tribu Hoodothripini. Se describe un nuevo género Hoodothripiella n.gen. El principal carácter para este nuevo taxón es la presencia de siete antenómeros, se restablece el género Hoodothripoides. Se incluyen figuras como también claves de identificación.
Effect of human papillomavirus 16/18 L1 viruslike particle vaccine among young women with preexisting infection: A randomized trial
(American Medical Association, 2007-08-15) Hildesheim, Allan; Herrero, Rolando; Wacholder, Sholom; Rodríguez, Ana Cecilia; Solomon, Diane; Bratti Verdejo, M. Concepcion; Schiller, John T.; González Sequeira, María Paula; Dubin, Gary; Porras Gutiérrez, Carolina; Jiménez, Silvia E.; Lowy, Douglas R.
Context: Viruslike particle human papillomavirus (HPV) vaccines were designed to prevent HPV infection and development of cervical precancers and cancer. Women with oncogenic HPV infections might consider vaccination as therapy. Objective: To determine whether vaccination against HPV types 16 and 18 increases the rate of viral clearance in women already infected with HPV. Design and Setting: Phase 3, masked, community-based randomized trial conducted in 2 provinces of Costa Rica. Participants: A total of 2189 women aged 18 to 25 years who were recruited between June 2004 and December 2005. Participants were positive for HPV DNA at enrollment, had at least 6 months of follow-up, and had follow-up HPV DNA results. Intervention: Participants were randomly assigned to receive 3 doses of a bivalent HPV-16/18 L1 protein viruslike particle AS04 candidate vaccine (n=1088) or a control hepatitis A vaccine (n=1101) over 6 months. Main Outcome Measures: Presence of HPV DNA was determined in cervical specimins by a molecular hybridization assay using chemiluminescence with HPV RNA probes and by polymerase chain reaction using SPF10 primers and a line probe assay detection system before vaccination and by polymerase chain reaction after vaccination. We compared rates of type-specific viral clearance using generalized estimating equations methods at the 6-month visit (after 2 doses) and 12-month visit (after 3 doses) in the 2 study groups. Results: There was no evidence of increased viral clearance at 6 or 12 months in the group who received HPV vaccine compared with the control group. Clearance rates for HPV-16/18 infections at 6 months were 33.4% (82/248) in the HPV vaccine group and 31.6% (95/ 298) in the control group (vaccine efficacy for viral clearance, 2.5%; 95% confidence interval, − 9.8% to 13.5%). Human papillomavirus 16/18 clearance rates at 12 months were 48.8% (86/177) in the HPV vaccine group and 49.8% (110/220) in the control group (vaccine efficacy for viral clearance, −2.0% ; 95% confidence interval, −24.3% to 16.3%). There was no evidence of a therapeutic effect for other oncogenic or nononcogenic HPV categories, among women receiving all vaccine doses, among women with single infections, or among women stratified by the following entry variables: HPV-16/18 serology, cytologic results, HPV DNA viral load, time since sexual debut, Chlamydia trachomatis or Neisseria gonorrhoeae infection, hormonal contraceptive use, or smoking. Conclusion: In women positive for HPV DNA, HPV-16/18 vaccination does not accelerate clearance of the virus and should not be used to treat prevalent infections.
Promovamos las prácticas en salud auditiva y escucha segura. ¿Por cuánto tiempo estás dispuesto a escuchar?
(2025-07-07) Arias Ramírez, Denis Rodolfo
En el marco de los proyectos, gestionados por estudiantes, de Iniciativas Estudiantiles de Acción Social de la Vicerrectoría de Acción Social de la Universidad de Costa Rica, 2021-2022. El siguiente material aborda las vivencias, saberes, guías, conocimientos, compartidos entre los estudiantes y las comunidades costarricenses fomentando un vínculo entre la sociedad y la universidad pública. Se llevó a cabo gracias a la comunidad del Hospital de San Carlos, Ciudad Quesada, San Carlos, provincia de Alajuela, Costa Rica. Proyecto facilitado por la iniciativa estudiantil: IE-175 Ayúdame a escucharte mejor. Se espera que este material pueda ser de gran ayuda al momento de implementar prácticas para el autocuidado de la audición, la escucha segura y una optima salud auditiva. Al desarrollar dicho proyecto se buscó generar conciencia en la población trabajadora y pacientes de dicho hospital acerca de los efectos negativos del ruido excesivo. Cada uno de los capítulos de este material fue revisado por un equipo interdisciplinario en donde participaron personas especialistas en el área de audiología, educación, trabajo social y sociología. Este documento compila de cada uno de los talleres y charlas presentadas a la población participante, quienes además pudieron evaluar cada uno de los contenidos de las sesiones con la finalidad de validar los contenidos desarrollados. Se agradece especialmente al servicio de Tamizaje Auditivo Neonatal Universal del Hospital de San Carlos.
Creating foods for older adults: Emotional responses and liking of microwave-assisted thermal sterilization processed meals.
(2022-04-27) Romaniw, Olivia C.; Montero Díaz, María Laura; Sharma, Madhu; Ross, Carolyn F.; Duizer, Lisa M.
The purpose of this study was to examine emotional and liking responses to foods designed for older adults and made using microwave-assisted thermal sterilization technology (MATS). Six chicken pasta meals (three each with and without herbs) were formulated with three concentrations of salt at 100%, 75%, and 50%. Seventy-six community-dwelling older adults conducted sensory and emotional evaluations. Sensory testing involved measuring liking of various sensory attributes using a 9-point edonic scale, Just-about-right scales to measure appropriateness of the intensity of the attributes, and check-all-thatapply questions to identify perceived flavor and texture attributes. EsSense25 methodology was used for capturing food-evoked emotional responses. Significant differences existed in all measured sensory attributes and in 14 out of the 25 tested emotions across the six meals. Liking scores for all pastas with herbs and high salt pasta with no herbs were not significantly different for all tested attributes and fell between neither like nor dislike and like slightly on the 9-point hedonic scale. These samples were also associated with positive emotions related to energy and activation. Low-salt pastas with no herbs were consistently the least liked samples and evoked negative emotions. Results show that sodium content can be reduced by up to half when herbs are added to microwave-processed pasta meals without compromising liking.