Do American and Korean Instructors Hold the Same Perceptions of Arguments for and against Online Teaching? An Exploratory Study

This study compared instructors’ perceptions of arguments for and against online teaching in the United States and South Korea and examined the impact of selected demographical variables on these perceptions. Results showed that American and Korean instructors had similar perceptions about online teaching. However, the two groups significantly differed on the extent of agreement or disagreement with the statements included in the study. Several of the demographic variables that were examined in the study had significant impacts on participants’r esponses

Exploratory Study of the Factors that Influence the Adoption of Electronic Commerce in a Latin-American Context

The strong pattern of inequality that marks Latin America and the Caribbean (LAC) is repeated, although with different characteristics, in access to information and communication technologies (ICTs). Although it is not currently possible to demonstrate empirically, in great detail, that mobile telephony is making a substantive contribution to poverty reduction in LAC, we aim to shed light on certain areas. First, we argue that mobile telephony penetration has been significantly higher than that of other ICTs among the poorest sectors of the population. Second, by constructing Gini indexes of phone access, data show that the distribution of mobile telephony is consistently more equitable than that of landlines in LAC. Third, the high degree of mobile telephone penetration in poor sectors sparks new implications about possible strategies and tools for promoting other ICTs, which have had comparatively less impact so far. We seek then to contribute to the discussion on design –or redesign- of public policies that focus on development through the use of ICTs in the region

Inverse Electron-Demand [4 + 2]-Cycloadditions of Ynamides: Access to Novel Pyridine Scaffolds

Functionalized polycyclic aminopyridines are central to the chemical sciences, but their syntheses are still hampered by a number of shortcomings. These nitrogenated heterocycles can be efficiently prepared by an intramolecular inverse electron demand hetero Diels–Alder ( ih DA) cycloaddition of ynamides to pyrimidines. This ihDA/rDA sequence is general in scope and affords expedient access to novel types of aminopyridinyl scaffolds that hold great promise in terms of exit vector patterns

Acceptance of social networking sites by older people before and after COVID-19 confinement: a repeated cross-sectional study in Chile

This study aims to examine the capacity of the Theory of Planned Behaviour (TPB) to explain the intention to use social networking sites by older people in two time periods, before and after their confinement by the SARS-CoV-2 virus, as well as the evolution of effects (paths) over time of TPB’s determinants. Based on the samples of 384 and 383 Chilean adults collected before and after confinement, the evolution of the effects (paths) was analysed using the TPB model applying the PLS-SEM technique. In conclusion, as older people begin to use social networking sites to connect with their families and people of interest during confinement, their attitudes become more significant, their perceptions of control become less important, and social pressures remain permanent in time

Identification of iridoid synthases from Nepeta species : Iridoid cyclization does not determine nepetalactone stereochemistry

Nepetalactones are iridoid monoterpenes with a broad range of biological activities produced by plants in the Nepeta genus. However, none of the genes for nepetalactone biosynthesis have been discovered. Here we report the transcriptomes of two Nepeta species, each with distinctive profiles of nepetalactone stereoisomers. As a starting point for investigation of nepetalactone biosynthesis in Nepeta, these transcriptomes were used to identify candidate genes for iridoid synthase homologs, an enzyme that has been shown to form the core iridoid skeleton in several iridoid producing plant species. Iridoid synthase homologs identified from the transcriptomes were cloned, heterologously expressed, and then assayed with the 8-oxogeranial substrate. These experiments revealed that catalytically active iridoid synthase enzymes are present in Nepeta, though there are unusual mutations in key active site residues. Nevertheless, these enzymes exhibit similar catalytic activity and product profile compared to previously reported iridoid synthases from other plants. Notably, four nepetalactone stereoisomers with differing stereochemistry at the 4α and 7α positions – which are generated during the iridoid synthase reaction – are observed at different ratios in various Nepeta species. This work strongly suggests that the variable stereochemistry at these 4α and 7α positions of nepetalactone diastereomers is established further downstream in the iridoid pathway in Nepeta. Overall, this work provides a gateway into the biosynthesis of nepetalactones in Nepeta

How Performance and Self-Efficacy Influence the Ease of Use of Object-Orientation: The Moderating Effect of Prior Training

In this study, we empirically explore how task performance and domain-specific self-efficacy influence the perceived ease of use (PEU) of object-oriented techniques. We hypothesize that both self-efficacy and performance positively influences PEU according to existing literature. However, we speculate that the effect of self-efficacy on PEU, even though still positive, becomes weaker when subjects are given prior training in structured analysis. In contrast, the relationship between performance and PEU becomes stronger when subjects are given the same training. We conducted two tests and collected data from a group of 79 subjects. We found a strong support for most of the research hypotheses

Perceived Strategic Value and Adoption of Electronic Commerce: An Empirical Study of Small and Medium Sized Businesses

By combining two independent research streams, we examine the strategic value and adoption of electronic commerce (e-commerce) as perceived by top managers in small and medium sized enterprises (SME). We propose a research model that posits three factors that have been found to be influential in previous research in the perception of strategic value of other information technologies. Inspired by the technology acceptance model of Davis [14] and other relevant research in the area, we also identify four factors that we believe will influence e-commerce adoption. We hypothesize a causal link between the perceived strategic value of e-commerce and e-commerce adoption. To validate the research model, we collected data from top managers/owners of SME via an Internet survey. Confirmatory factor analysis was used to test the factors utilized in this study while canonical correlation analysis was employed to validate the causal link between the two main constructs of this study

Explorando la adopción de ERP con el modelo Business Process Change (BPC): Tres casos de estudio en Chile

Si bien existen numerosos estudios enfocados en determinar factores críticos de éxito en la adopción de ERP, mayoritariamente no se basan en teoría y se realizan en países desarrollados. Basada en el modelo Business Process Change (BPC), el objetivo de este trabajo es explorar el proceso de implementación de ERP de tres importantes empresas Chilenas, con el fin de identificar los factores que favorecen o inhiben una implementación exitosa. Los resultados obtenidos confirman muchos de los factores críticos de éxito encontrados en la literatura y ratifican la importancia del modelo BPC como base en el estudio de este fenómeno

Predictive model to reduce the dropout rate of university students in Perú: Bayesian Networks vs. Decision Trees

El texto completo de este trabajo no está disponible en el Repositorio Académico UPC por restricciones de la casa editorial donde ha sido publicado.This research proposes a prediction model that might help reducing the dropout rate of university students in Peru. For this, a three-phase predictive analysis model was designed which was combined with the stages proposed by the IBM SPSS Modeler methodology. Bayesian network techniques was compared with decision trees for their level of accuracy over other algorithms in an Educational Data Mining (EDM) scenario. Data were collected from 500 undergraduate students from a private university in Lima. The results indicate that Bayesian networks behave better than decision trees based on metrics of precision, accuracy, specificity, and error rate. Particularly, the accuracy of Bayesian networks reaches 67.10% while the accuracy for decision trees is 61.92% in the training sample for iteration with 8:2 rate. On the other hand, the variables athletic person (0.30%), own house (0.21%), and high school grades (0.13%) are the ones that contribute most to the prediction model for both Bayesian networks and decision trees