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Autonomy and Foreign Language Learning in a Virtual Learning Environment
Digitalised learning with its promise of autonomy, enhanced learner choice, independence and freedom, is an intuitive and appealing construct but closer examination reveals it to be a rather simplistic proposition, raising the following questions. -What do we mean by autonomy? -What are we implying about the role of the teacher, the classroom, and interaction between learners? -What do we understand about the impact of technology on the ecology of the learning environment? This book describes the use of a Virtual Learning Environment (VLE) by a group of advanced English language learners in Mexico, comparing what students thought and what they did in response to the technology. The theoretical aim of the book is to work towards the construction of a theory of the development of autonomy and virtual learning in an EFL context. Enhanced understanding about the relationship between autonomy and technology has the potential to inform academics, software designers, materials writers, teacher educators, and teachers and to help learners in their quest to acquire a foreign language.
eBook
Engineers' education in digital era
The Fourth Industrial Revolution has already taken around the world. Decision taking at industries is more and more dependent on new technologies and processes, which demand updating and adjustment of the engineering education. Through a systematized literature revision, this article aims to search, select and prioritize bibliographic sources which reflect relevant initiatives that may work as a reference for engineering bachelor's degree courses. 50 most relevant articles were selected and analyzed from 4,333 articles published in the Scopus database. The results show the 10 main authors, the 9 main journals and the 10 main institutions among the 50 most relevant articles, as references in the analyzed sample. Regarding aspects for the improvement of engineers education, one can highlight PBL (Project-Based Learning), Competency-Based Education and focus on holistic education. This research may encourage reflection, awareness and improvement by the ones interested in the study of engineers' education, by integrating market demand, learners' expectations and academic excellence, in order to contribute to the growth of scientific and practical knowledge and of society technological development.
Journal Article
First detection and characterization of Salmonella spp. in poultry and swine raised in backyard production systems in central Chile
Little is known about Salmonella serovars circulating in backyard poultry and swine populations worldwide. Backyard production systems (BPS) that raise swine and/or poultry are distributed across Chile, but are more heavily concentrated in central Chile, where industrialized systems are in close contact with BPS. This study aims to detect and identify circulating Salmonella serovars in poultry and swine raised in BPS. Bacteriological Salmonella isolation was carried out for 1744 samples collected from 329 BPS in central Chile. Faecal samples were taken from swine, poultry, geese, ducks, turkeys and peacocks, as well as environmental faecal samples. Confirmation of Salmonella spp. was performed using invA-polymerase chain reaction (PCR). Identification of serovars was carried out using a molecular serotyping approach, where serogroups were confirmed by a multiplex PCR of Salmonella serogroup genes for five Salmonella O antigens (i.e., D, B, C1, C2-C3, and E1), along with two PCR amplifications, followed by sequencing of fliC and fljB genes. A total of 25 samples (1·4% of total samples) from 15 BPS (4·6 % of total sampled BPS) were found positive for Salmonella. Positive samples were found in poultry (chickens and ducks), swine and environmental sources. Molecular prediction of serovars on Salmonella isolated showed 52·0% of S. Typhimurium, 16·0% of S. Infantis, 16·0% S. Enteritidis, 8·0% S. Hadar, 4·0% S. Tennessee and 4·0% S. Kentucky. Poor biosecurity measures were found on sampled BPS, where a high percentage of mixed confinement systems (72·8%); and almost half of the sampled BPS with improper management of infected mortalities (e.g. selling the carcasses of infected animals for consumption). Number of birds other than chickens (P = 0·014; OR = 1·04; IC (95%) = 1·01–1·07), mixed productive objective (P = 0·030; OR = 5·35; IC (95%) = 1·24–27·59) and mixed animal replacement origin (P = 0017; OR = 5·19; IC (95%) = 1·35–20·47) were detected as risk factors for BPS positivity to Salmonella spp. This is the first evidence of serovars of Salmonella spp. circulating in BPS from central Chile. Detected serovars have been linked to human and animal clinical outbreaks worldwide and in Chile, highlighting the importance of BPS on the control and dissemination of Salmonella serovars potentially hazardous to public health.
Journal Article
Assessing Antibiotic Residues in Poultry Eggs from Backyard Production Systems in Chile, First Approach to a Non-Addressed Issue in Farm Animals
Eggs are the main product generated from backyard poultry production systems (BPS) because they can quickly be consumed and sold to meet essential family needs. Nevertheless, antimicrobial residues can accumulate in this product. The objective of this study was to evaluate the presence of antimicrobial residues in eggs produced by poultry kept in BPS in central Chile. To assess this, eggs were obtained from 83 BPS and analysed to evaluate the presence of antibiotic residues (families: tetracyclines, beta-lactams, aminoglycosides and macrolides), using a Four-Plate Test screening method for the detection, based on a bacterial growth inhibition method. Results show a lack of biosecurity procedures at BPS level, making these systems susceptible to the dissemination of antimicrobial residues. These include intensive animal production units in the proximity, and the presence of shared watercourses with other farms. Furthermore, 66% of the surveyed owners are indicated as giving pharmacological treatments to their chickens. Eggs from 61 BPS were positive for at least one antimicrobial. Fifty-three BPS were positive for more than one antimicrobial, and one BPS was positive for all four antimicrobials tested. Consequently, there is a risk that poultry eggs produced in BPS in central Chile carry residues of different families of antimicrobials.
Journal Article
Novel Low Pathogenic Avian Influenza H6N1 in Backyard Chicken in Easter Island (Rapa Nui), Chilean Polynesia
Little is known about the prevalence of avian influenza viruses (AIV) in wildlife and domestic animals in Polynesia. Here, we present the results of active AIV surveillance performed during two sampling seasons in 2019 on Easter Island (Rapa Nui). Tracheal and cloacal swabs as well as sera samples were obtained from domestic backyard poultry, while fresh faeces were collected from wild birds. In addition to detecting antibodies against AIV in 46% of the domestic chickens in backyard production systems tested, we isolated a novel low pathogenic H6N1 virus from a chicken. Phylogenetic analysis of all genetic segments revealed that the virus was closely related to AIV’s circulating in South America. Our analysis showed different geographical origins of the genetic segments, with the PA, HA, NA, NP, and MP gene segments coming from central Chile and the PB2, PB1, and NS being closely related to viruses isolated in Argentina. While the route of introduction can only be speculated, our analysis shows the persistence and independent evolution of this strain in the island since its putative introduction between 2015 and 2016. The results of this research are the first evidence of AIV circulation in domestic birds on a Polynesian island and increase our understanding of AIV ecology in region, warranting further surveillance on Rapa Nui and beyond.
Journal Article
Long-Term Interactions of Salmonella Enteritidis With a Lytic Phage for 21 Days in High Nutrients Media
Salmonella spp. is a relevant foodborne pathogen with worldwide distribution. To mitigate Salmonella infections, bacteriophages represent an alternative to antimicrobials and chemicals in food animals and food in general. Bacteriophages (phages) are viruses that infect bacteria, which interact constantly with their host. Importantly, the study of these interactions is crucial for the use of phages as a mitigation strategy. In this study, experimental coevolution of Salmonella Enteritidis ( S . Enteritidis) and a lytic phage was conducted in tryptic soy broth for 21 days. Transfer to fresh media was conducted daily and every 24 hours, 2 mL of the sample was collected to quantify Salmonella OD 600 and phage titter. Additionally, time-shift experiments were conducted on 20 colonies selected on days 1, 12, and 21 to evaluate the evolution of resistance to past (day 1), present (day 12), and future (day 21) phage populations. The behavior of the dynamics was modeled and simulated with mathematical mass-action models. Bacteria and phage from days 1 and 21 were sequenced to determine the emergence of mutations. We found that S . Enteritidis grew for 21 days in the presence and absence of the phage and developed resistance to the phage from day 1. Also, the phage was also able to survive in the media for 21 days, however, the phage titer decreased in approx. 3 logs PFU/mL. The stability of the lytic phage population was consistent with the leaky resistance model. The time-shift experiments showed resistance to phages from day 1 of at least 85% to the past, present, and future phages. Sequencing of S . Enteritidis showed mutations in genes involved in lipopolysaccharide biosynthesis genes rfbP and rfbN at day 21. The phage showed mutations in the tail phage proteins responsible for recognizing the cell surface receptors. These results suggest that interactions between bacteria and phage in a rich resource media generate a rapid resistance to the infective phage but a fraction of the population remains susceptible. Interactions between Salmonella and lytic phages are an important component for the rational use of phages to control this important foodborne pathogen.
Journal Article
Arquitectura (y) narrativa: museografía de San Francisco de la Alameda 1929–2020
Esta tesis busca levantar y registrar arquitectónicamente los diferentes modelos y detalles museográficos que han conformado al Museo de Arte Colonial de San Francisco a lo largo de los años, un programa inscrito en un conjunto arquitectónico de más de 400 años de antigüedad. Esto se hace por medio de una documentación compuesta de 3 partes: un levantamiento arquitectónico preciso del claustro en la actualidad, luego, un registro graficado de su colección fija más notable, que es la serie de 54 pinturas del S.XVII sobre la vida de San Francisco, y finalmente, una reconstrucción temporal que cruza estos dos materiales producidos con registros fotográficos, entrevistas, textos y otros tipos de fuentes de investigación que informan el contexto arquitectónico y disposición de los cuadros. Entendiendo a los museos como una pieza de arquitectura pública, activa y con poder ideológico y socio-cultural, el fin de éste estudio es, por un lado, comprender e identificar de mejor manera la carga cultural que subyace al conjunto arquitectónico más antiguo de Santiago, sirviendo a futuras intervenciones patrimoniales y reformulaciones museológicas que pretendan llevarse a cabo de manera informada y proactiva sobre un edificio icónico de la Iglesia Católica y de Chile. Y por otro lado, abrir una discusión sobre la manera en que la arquitectura juega un rol curatorial sobre una colección permanente de museo, e incidentalmente, sobre una narrativa.
Dissertation
Screening the Presence of Non-Typhoidal Salmonella in Different Animal Systems and the Assessment of Antimicrobial Resistance
Salmonella is a major bacterial foodborne pathogen that causes the majority of worldwide food-related outbreaks and hospitalizations. Salmonellosis outbreaks can be caused by multidrug-resistant (MDR) strains, emphasizing the importance of maintaining public health and safer food production. Nevertheless, the drivers of MDR Salmonella serovars have remained poorly understood. In this study, we compare the resistance profiles of Salmonella strains isolated from 4047 samples from domestic and wild animals in Chile. A total of 106 Salmonella strains (2.61%) are isolated, and their serogroups are characterized and tested for susceptibility to 16 different antimicrobials. The association between antimicrobial resistance (AMR) and a subset of independent variables is evaluated using multivariate logistic models. Our results show that 47 antimicrobial-resistant strains were found (44.3% of the total strains). Of the 47, 28 correspond to single-drug resistance (SDR = 26.4%) and 19 are MDR (17.9%). S. Enteritidis is highly persistent in animal production systems; however, we report that serogroup D strains are 18 times less likely to be resistant to at least one antimicrobial agent than the most common serogroup (serogroup B). The antimicrobials presenting the greatest contributions to AMR are ampicillin, streptomycin and tetracycline. Additionally, equines and industrial swine are more likely to acquire Salmonella strains with AMR. This study reports antimicrobial-susceptible and resistant Salmonella in Chile by expanding the extant literature on the potential variables affecting antimicrobial-resistant Salmonella.
Journal Article