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Profiles of University Students Who Graduate on Time: A Cohort Study from the Chilean Context
No full textGraduating from higher education on time is an important topic, given its relation to students' academic success and the efficiency of the institutions. However, a low percentage of university students finish their studies on time, which poses a challenge that requires the identification of the factors that account for this phenomenon. This study aimed to identify and characterize profiles of students who graduate on time. The population is 514 university students (45% men, 55% women), with an average age of 19.5 years (SD= 1.9) studying business at a university in Chile who belong to four cohorts entering between 2011 and 2014. The results obtained from the Classification and Regression Tree (CART) technique demonstrate eight student profiles constructed considering different variables at the pre-university, transition-motivation, and university levels. As the primary outcome, the profile of the student who graduates on time is characterized by a good performance in the first year of university, enters university right after high school, and takes advantage of institutional support by participating in academic tutoring. These findings suggest that institutions can implement specific strategies from the beginning of the university journey to promote on-time graduation
THINNING WOOD PROPERTIES OF <i>Nothofagus alpina</i> UNDER THREE DIFFERENT SILVICULTURAL CONDITIONS
No full textThe main objective of this study was to assess the properties of Nothofagus alpina (rauli) wood from thinning that originates from two sites with intensive silviculture and one similar to a secondary growth forest, with different soil, climatic conditions and age. To achieve this, some mechanical, physical and chemical-crystalline properties were characterized; studying the differences from pith to bark and between the selected trees that were taken from the thinning of the three plantations. Among the studied plantation sites, there were statistical differences in equilibrium moisture content, density and modulus of elasticity. Furthermore, FT-IR was able to differentiate the chemical-crystalline compositions from pith to bark and between plantations, while the X-Ray diffraction showed differences in the crystallinity index. It was possible to differentiate between the sites with a more intense silvicultural intervention and the one with more variable growth conditions
Development and Impact of a Handbook for Urban Sustainability Teaching in Three Chilean Universities
No full textSince active learning of Urban Sustainability (US) represents an area in growing development, contributing to this corpus with new concrete experiences, particularly those from the Global South, is necessary. This article aims to systematize the pilot implementation of an US learning manual in Chilean higher education institutions that emerged from the Urban Explorations: Sustainable Territory course taught at the Pontificia Universidad Cat & oacute;lica. Therefore, the authors carried out a qualitative research based on content analysis that used a theoretical-applied methodological process: first, a survey was carried out on former students of the pioneer course considering 5 parameters: contents, teaching organization, teaching methodologies, evaluation -feedback, and relationship between students - teaching staff. Then, based on the results of the survey, a handbook with didactic activities for the US was generated, and reviewed in a focus group with former students, professors at these universities, and expert peers. Subsequently, this manual was implemented in the course at 3 Chilean universities in a mixed way (on an online platform and some face -to -face activities) in 2022, and, in the end, it was evaluated in a new focus group carried out by the professors who taught the course. The first result corresponds to the survey where a high satisfaction with the course was observed in the 5 parameters evaluated (<70%). The second result is the analysis of the focus groups that used the same 5 parameters from the first revision of the handbook and in its final version. Finally, the authors discussed the idea that this project allows to approach the teaching of US in different Chilean territorial contexts from multiple perspectives, which highlights common interests that can serve for other Latin American educational centers to use this teaching material for higher education available online for free download in Spanish
Explanatory Factors of School Climate and School Identification: An Analysis of Multilevel Latent Profiles
No full textSchool climate is a highly relevant variable that is associated with a series of positive results. However, there are still few studies that have statistically modelled the simultaneous influence of structural variables at the school level on the individual perception of the school climate and identification. This study had two objectives: (1) Identify school climate and school identification profiles at the individual and school levels. (2) Relate school climate and school identification profiles to factors located at the individual and school levels. The participants were selected from a probabilistic and stratified sample, n = 2070 adolescents (40.6% men, 59.4% women), aged between 13 and 18 years (M = 14.64, SD = 0.718), from 28 secondary schools in Chile. The results allowed us to identify four clusters at the student level and two classes of school climate at the school level. The explanatory factors at the individual level were Cognitive engagement (p < 0.001), Academic Expectations (p < 0.001), Positive Attitude to Authority (p < 0.001) and Family Conflict (p < 0.001). The explanatory factor at the school level was the school vulnerability index (p = 0.031). Finally, the explanatory effects of factors at individual and school levels on school climate are theoretically discussed
Contributions of the notion of cosmosophy to the formulation of critical sustainability sciences
No full textBenthic macroinvertebrates community structure and physical-chemical characteristics at Lauca River Basin high altitude wetlands, Altiplano, Chile
No full textHigh Andean freshwater ecosystems are highly threatened by scarce water availability, species invasion, and global climate change, so generating knowledge about their ecological characteristics is extremely important for conservation decision-making. In this work, the seasonal variations and relationships between physico-chemical variables and the structure and composition of the macroinvertebrate community were analyzed considering 'season', 'type of ecosystem' and 'site' factors. Five sites of representative ecosystems at Lauca River Basin of the Chilean Altiplano were sampled, two of them lentic and three lotic. Two field-sampling periods within a year according to the pre- and post-rain seasons characteristic of the Altiplano climate were considered. Thirty-five taxa were identified, and it was observed that the taxa Orthocladiinae, Austrelmis sp., Hyallela cf kochi, Podonominae and Helicopsychidae were indicator taxa that contributed the most to differences among sites or ecosystems (>= 10 %.). No significant differences were found in the alpha diversity indicators used, except for some abundance values and Pielou's Evenness index (J '), which varied significantly between lotic and lentic systems. The results of the ordination analysis showed a significant differentiation considering physical and chemical variables and macroinvertebrates assemblages that responded to 'sites' (ANOSIM R Global = 0.64, p = 0.001) and 'type of ecosystem' factors (ANOSIM R Global = 0.31, p = 0.02). The 'season' factor was not statistically significant to explain the variability of biological data (ANOSIM R Global = -0.003, p = 0.47) and was slight and marginally significant with the physical and chemical data (ANOSIM R Global = 0.1, p = 0.04). In addition, the linear redundancy analysis (RDA) showed that physico-chemical variables related to hardness, temperature, phosphorous, and nitrogen explained most of the variance in the biological data (the first two canonical axes RDA1 and RDA2 explained 45.23 % of the total variation, p = 0.004). These results support the relevance of local conditions for high altitude wetlands and how those environmental characteristics can be reflected in the macroinvertebrate assemblages that inhabit them
Effects of type of substrate and dilution rate on fermentation in serial rumen mixed cultures
No full textForages and concentrates have consistently distinct patterns of fermentation in the rumen, with forages producing more methane (CH4) per unit of digested organic matter (OM) and higher acetate to propionate ratio than concentrates. A mechanism based on the Monod function of microbial growth has been proposed to explain the distinct fermentation pattern of forages and concentrates, where greater dilution rates and lower pH associated with concentrate feeding increase dihydrogen (H2) concentration through increasing methanogens growth rate and decreasing methanogens theoretically maximal growth rate, respectively. Increased H2 concentration would in turn inhibit H2 production, decreasing methanogenesis, inhibit H2-producing pathways such as acetate production via pyruvate oxidative decarboxylation, and stimulate H2-incorporating pathways such as propionate production. We examined the hypothesis that equalizing dilution rates in serial rumen cultures would result in a similar fermentation profile of a high forage and a high concentrate substrate. Under a 2 x 3 factorial arrangement, a high forage and a high concentrate substrate were incubated at dilution rates of 0.14, 0.28, or 0.56 h-1 in eight transfers of serial rumen cultures. Each treatment was replicated thrice, and the experiment repeated in two different months. The high concentrate substrate accumulated considerably more H2 and formate and produced less CH4 than the high forage substrate. Methanogens were nearly washed-out with high concentrate and increased their initial numbers with high forage. The effect of dilution rate was minor in comparison to the effect of the type of substrate. Accumulation of H2 and formate with high concentrate inhibited acetate and probably H2 and formate production, and stimulated butyrate, rather than propionate, as an electron sink alternative to CH4. All three dilution rates are considered high and selected for rapidly growing bacteria. The archaeal community composition varied widely and inconsistently. Lactate accumulated with both substrates, likely favored by microbial growth kinetics rather than by H2 accumulation thermodynamically stimulating electron disposal from NADH into pyruvate reduction. In this study, the type of substrate had a major effect on rumen fermentation largely independent of dilution rate and pH
China and India’s Health Diplomacy in Africa during the COVID-19 Pandemic
Get PDFLa denominada "diplomacia de la salud" ha adquirido un papel fun-damental en las Relaciones Internacionales contemporáneas, especialmente en momentos de crisis sanitaria global, como ocurre con la pandemia de la Co-vid-19. Países como China e India se han destacado en este ámbito, principal-mente a través de sus actividades de Cooperación Sur-Sur (CSS) con naciones del Sur Global. Este artículo tiene como objetivo analizar de manera comparativa la "diplomacia de la salud" implementada por China e India en África durante la pandemia de la Covid-19. La pregunta que guía este estudio es: "¿Cómo han utilizado estos países las políticas de Cooperación Internacional para el Desarrollo (CID) en la región para combatir la pandemia?" Para responder a esta interrogante, examinamos cómo las prácticas de CID de estos países se relacionan con sus intereses geopolíticos y económicos en la región. Los re-sultados del análisis indican que la actuación china se ha destacado a través de donaciones de vacunas, insumos y equipamiento hospitalario, además de acciones en el ámbito de la cooperación financiera, como el alivio de la deuda. El caso indio sobresale por la predominancia de la cooperación técnica, mediante la compartición de tecnologías para telecomunicaciones y teleconsultas, además del suministro de vacunas, medicamentos y equipamiento hospitalario.So-called health diplomacy has become a fundamental element in contemporary International Relations, especially in the context of world health crises such as the global COVID-19 pandemic. Countries like China and India have stood out in this field through their South-South Cooperation (SSC) ac-tivities, together with countries of the Global South. This article seeks to com-pare the health diplomacy conducted by China and India in Africa within the context of the COVID-19 pandemic. Our guiding question is: How have these countries employed International Development Cooperation (IDC) policies in this region to fight the pandemic? To answer this, we have analyzed how the IDC practices of these countries are related to their geopolitical and economic interests in the region. The results indicate that China stands out in terms of its vaccine donations, hospital supplies, and equipment, in addition to financial co-operation such as debt relief. India, meanwhile, stands out in terms of financial cooperation, based on sharing telecommunication technologies and tele-consulting, in addition to supplying vaccines, medication, and hospital equipment
A Heavy-Tailed Distribution Based on the Lomax-Rayleigh Distribution with Applications to Medical Data
No full textIn this paper, we extend the Lomax-Rayleigh distribution to increase its kurtosis. The construction of this distribution is based on the idea of the Slash distribution, that is, its representation is based on the quotient of two independent random variables, one being a random variable with a Lomax-Rayleigh distribution and the other a beta(q,1). Based on the representation of this family, we study its basic properties, such as moments, coefficients of skewness, and kurtosis. We perform statistical inference using the methods of moments and maximum likelihood. To illustrate this methodology, we apply it to two real data sets
Drying treatment for sludges of the Chilean salmon farming industry and its potential as an agricultural soil amendment
No full textOrganic waste generation in aquaculture worldwide requires circular economy approaches. The revalorization of wastes in the Chilean salmon industry could be a potential soil amendment. We investigated the thermo-drying process on salmon sludge, evaluating it as an alternative to reusing in horticulture. The chemical characterization of untreated sludge (wet sludges: WS) and dried sludges (DS) were evaluated with thermogravimetry, IR spectroscopy, and fluorescence. Additionally, the germination index of the DS was determined in L. sativa, R. sativus, and S. lycopersicum. The results show that DS reduces salinity, ammonium content, and pathogens compared to WS. During the thermic process, there were no significant decreases in organic matter, phosphorus, potassium, and humic and fulvic substances. The high salinity in DS inhibited seed germination. This research constituted a novel contribution to studying the DS as a strategy for horticultural production. In the same way, the drying technology for salmon sludge favored the management of wastes, contributing to the circular economy in both the agricultural and aquaculture sectors. However, we recommend considering that excessive incorporation of DS into germination substrates or direct application into the soil could affect the crop's performance due to its high salinity