Student experiences of two small group learning-teaching formats: Seminar and fishbowl

Abstract Introduction As teaching strategies, the seminar and fishbowl approaches promote active learning and shift the focus from the teacher to the learner. The aim of this study was to compare the self-reported perceptions of each student-centred teaching technique amongst a group of dental students as well as resultant quiz scores after each teaching technique. Material and Methods During the first semester of 2017, all year-3 (N = 88) Semiology and year-5 (N = 71) Oral Surgery students participated in weekly seminars in which teams of students from both cohorts were given an actual clinical case to study; a diagnosis and treatment plan would be rendered, and an oral case presentation would be presented to the rest of the class. In the second semester, the same students tried to solve similar clinical cases using the fishbowl training format. A course coordinator provided final feedback, and the session culminated with a quiz. Students were invited to provide quantitative and qualitative perceptions whilst quiz scores obtained during seminar and fishbowl teaching formats were compared. Results and Discussion A total of 97 (61%) seminar and 92 (58%) fishbowl students provided insights regarding these teaching techniques. Both cohorts believed the fishbowl format allowed them to be actively involved. However, only year-3 students gave the fishbowl format a significantly higher score than the seminar format, considering it an attractive format that allowed them to learn. In contrast, year-5 students believed the seminars met their expectations better than the fishbowl format. Interesting clinical cases as well as the final round of feedback were qualitative themes reported by both cohorts. The mean seminar and fishbowl quiz scores were statistically significant different for year-3 students (

Artificial Neural Network and a Nonlinear Regression Model for Predicting Electrical Pole Crash

This paper presents the investigation about a problem situation that Electric Distributor Companies are facing in Chile resulting from transit accidents. The number of vehicle crashes to power distribution poles and street lighting has grown. This situation causes discomfort to citizen and mainly to the neighbors due to power cuts and even on occasion , losses of human lives because of the accident that have occurred. Based on previous research, the accidents are not random nor chance dependent, but the majority of transit accident follow parameters or variables from the scenery where it occurs. In order to analyze the variables and the degree this variables affect the accidents, a model of Perceptron and Multipercetron Artificial Neural Networks and a Multiple Nonlinear Regression model are proposed. An empirical study was made; collecting data from a distributor company and from Chilean National Traffic Safety Commission, where the more frequent variables involved in accidents were determined to develop the mentioned models. These variables were investigated and also their influence on the occurrence of vehicle crashes to power distribution poles could be confirmed. With this data, the prediction of post crashes was developed, where through the application of the neural network and multiple nonlinear regression, revealed 95.7% of acceptable predictions. This study will bring benefits to power distribution companies considering a risk index in the streets, based on the number of crashes of poles per street; this will allow optimal decisions in future electrical distribution projects avoiding critical areas

The RNA Chaperone Hfq Participates in Persistence to Multiple Antibiotics in the Fish Pathogen Yersinia ruckeri

Indexación: ScopusYersinia ruckeri causes outbreaks of enteric redmouth disease in salmon aquaculture all over the world. The transient antibiotic tolerance exhibited by bacterial persisters is commonly thought to be responsible for outbreaks; however, the molecular factors underlying this behavior have not been explored in Y. ruckeri. In this study, we investigated the participation of the RNA chaperone Hfq from Y. ruckeri in antibiotic persistence. Cultures of the hfq-knockout mutant (∆hfq) exhibited faster replication, increased ATP levels and a more reductive environment than the wild type. The growth curves of bacteria exposed to sublethal concentrations of ampicillin, oxolinic acid, ciprofloxacin and polymyxin B revealed a greater susceptibility for the ∆hfq strain. The time-kill curves of bacteria treated with the antibiotics mentioned above and florfenicol, using inoculums from exponential, stationary and biofilm cultures, demonstrated that the ∆hfq strain has significant defects in persister cells production. To shed more light on the role of Hfq in antibiotic persistence, we analyzed its dependence on the (p)ppGpp synthetase RelA by determining the persister cells production in the absence of the relA gene. The ∆relA and ∆relA∆hfq strains displayed similar defects in persister cells formation, but higher than ∆hfq strain. Similarly, stationary cultures of the ∆relA and ∆relA∆hfq strains exhibited comparable levels of ATP but higher than that of the ∆hfq strain, indicating that relA is epistatic over hfq. Taken together, our findings provide valuable information on antibiotic persistence in Y. ruckeri, shedding light on the participation of Hfq in the persistence phenomenon. © 2021 by the authors. Licensee MDPI, Basel, Switzerland

The RNA Chaperone Hfq Participates in Persistence to Multiple Antibiotics in the Fish Pathogen Yersinia ruckeri

Yersinia ruckeri causes outbreaks of enteric redmouth disease in salmon aquaculture all over the world. The transient antibiotic tolerance exhibited by bacterial persisters is commonly thought to be responsible for outbreaks; however, the molecular factors underlying this behavior have not been explored in Y. ruckeri. In this study, we investigated the participation of the RNA chaperone Hfq from Y. ruckeri in antibiotic persistence. Cultures of the hfq-knockout mutant (Δhfq) exhibited faster replication, increased ATP levels and a more reductive environment than the wild type. The growth curves of bacteria exposed to sublethal concentrations of ampicillin, oxolinic acid, ciprofloxacin and polymyxin B revealed a greater susceptibility for the Δhfq strain. The time-kill curves of bacteria treated with the antibiotics mentioned above and florfenicol, using inoculums from exponential, stationary and biofilm cultures, demonstrated that the Δhfq strain has significant defects in persister cells production. To shed more light on the role of Hfq in antibiotic persistence, we analyzed its dependence on the (p)ppGpp synthetase RelA by determining the persister cells production in the absence of the relA gene. The ΔrelA and ΔrelAΔhfq strains displayed similar defects in persister cells formation, but higher than Δhfq strain. Similarly, stationary cultures of the ΔrelA and ΔrelAΔhfq strains exhibited comparable levels of ATP but higher than that of the Δhfq strain, indicating that relA is epistatic over hfq. Taken together, our findings provide valuable information on antibiotic persistence in Y. ruckeri, shedding light on the participation of Hfq in the persistence phenomenon

Desarrollo de un producto de seguros aplicable al sector frutícola

127 páginasPresenta un análisis que muestra cómo se llegó a determinar y por qué un seguro aplicable al sector frutícola chileno. Indica que el resultado fue un seguro privado, del tipo riesgo múltiple, que cubre heladas, granizo, lluvias inoportunas y ventarrones, con una cobertura igual al 70 por ciento del rendimiento base o promedio y cuya indemnización sería igual a la diferencia entre la cobertura y el rendimiento real. Se determinó además, que, al menos en una primera etapa, este seguro será accesible a los productores de uva de mesa, manzanas, duraznos y nectarina, cuyos huertos se ubiquen en las regiones V, VI, VII y Metropolitana, siempre y cuando dichos huertos estén también en alguna de las 10 regiones homogéneas de seguro que se ha definido para su implementación. El contenido del análisis está estructurado en 10 capítulos y bajo los siguientes encabezamientos: 1) determinación de los riesgos que afectan el sector frutícola; 2) tratamiento de los riesgos que afectan al sector frutícola; 3) análisis de las características básicas de los seguros agrícolas; 4) estructura del seguro en desarrollo; 5) análisis y selección de los cultivos asegurables; 6) análisis del comportamiento histórico de los cultivos asegurables; 7) determinación de la cobertura (porcentaje del rendimiento base a garantizar); 8) aproximación a la tarificación; 9) análisis de tarifas y mercado; y 10) conclusiones

Isolation of a Novel Aggregatibacter actinomycetemcomitans Serotype b Bacteriophage Capable of Lysing Bacteria within a Biofilm▿†

A bacteriophage specific for Aggregatibacter actinomycetemcomitans serotype b, able to kill the bacterium within a biofilm, was isolated. Random mutagenesis of this phage rendered a bacteriophage able to kill 99% of the bacteria within a biofilm. This is the first report of a biocontrol experiment against A. actinomycetemcomitans

Inequidades en la prestación de servicios de salud en Latinoamérica y el Caribe

El presente libro recoge intervenciones, ponencias y comunicaciones, presentadas en el Simposio: INEQUIDADES EN LA PRESTACION DE SERVICIOS DE SALUD EN LATINOAMÉRICA Y EL CARIBE celebrado dentro del II CONGRESO CIENCIAS, TECNOLOGÍAS Y CULTURAS, los días 29 octubre a 1 de noviembre 2010. El Congreso fue organizado y tuvo su sede en la Universidad de Santiago, Chile. El Simposio tuvo el auspicio de la Red Latinoamericana de Historiadores en Ciencias de la Salud y de la Federación Latinoamericana y del Caribe de Instituciones de Bioética (FELAIBE)[email protected]