Exploring self-regulation through learning navigation pathways in online learning during the pandemic

Abstract. Online learning has shown significant growth as a powerful alternative method to deliver learning through the pandemic situation. In the meantime, many studies have been attempting to investigate how to provide education within online platforms effectively; however, a few have examined how students regulate their learning during online courses. Through the lens of self-regulated learning theory and Zimmerman’s cyclical model (2000), the present study examines how successful students and less successful students regulate their learning in hypermedia contexts. Moreover, the research aims to explore self-regulatory behaviors via the learning pathways between successful students and less successful students in a learning management system. The process-oriented method was applied to investigate the student’s learning paths from the log data collected. The coding was done based on a new coding scheme created through the lens of self-regulated learning theories, in which half of the events were assigned with self-regulatory activities due to the lack of theoretical explanation. The frequency analysis and process mining analysis of coded learning events were generated to examine the differences in self-regulated learning between successful and less successful students. The results indicate how successful and less successful students regulate differently in their learning navigation. For educators, the study provides insights to better design online learning courses and suggests self-regulatory strategies to support students in hypermedia contexts

Performance analysis of multihop full-duplex NOMA systems with imperfect interference cancellation and near-field path-loss

Outage probability (OP) and potential throughput (PT) of multihop full-duplex (FD) nonorthogonal multiple access (NOMA) systems are addressed in the present paper. More precisely, two metrics are derived in the closed-form expressions under the impact of both imperfect successive interference cancellation (SIC) and imperfect self-interference cancellation. Moreover, to model short transmission distance from the transmit and receive antennae at relays, the near-field path-loss is taken into consideration. Additionally, the impact of the total transmit power on the performance of these metrics is rigorously derived. Furthermore, the mathematical framework of the baseline systems is provided too. Computer-based simulations via the Monte Carlo method are given to verify the accuracy of the proposed framework, confirm our findings, and highlight the benefits of the proposed systems compared with the baseline one.Web of Science231art. no. 52

The impact of environmental and climatic variation on the spatiotemporal trends of hospitalized pediatric diarrhea in Ho Chi Minh City, Vietnam.

It is predicted that the integration of climate-based early warning systems into existing action plans will facilitate the timely provision of interventions to diarrheal disease epidemics in resource-poor settings. Diarrhea remains a considerable public health problem in Ho Chi Minh City (HCMC), Vietnam and we aimed to quantify variation in the impact of environmental conditions on diarrheal disease risk across the city. Using all inpatient diarrheal admissions data from three large hospitals within HCMC, we developed a mixed effects regression model to differentiate district-level variation in risk due to environmental conditions from the overarching seasonality of diarrheal disease hospitalization in HCMC. We identified considerable spatial heterogeneity in the risk of all-cause diarrhea across districts of HCMC with low elevation and differential responses to flooding, air temperature, and humidity driving further spatial heterogeneity in diarrheal disease risk. The incorporation of these results into predictive forecasting algorithms will provide a powerful resource to aid diarrheal disease prevention and control practices in HCMC and other similar settings

Finishing the euchromatic sequence of the human genome

The sequence of the human genome encodes the genetic instructions for human physiology, as well as rich information about human evolution. In 2001, the International Human Genome Sequencing Consortium reported a draft sequence of the euchromatic portion of the human genome. Since then, the international collaboration has worked to convert this draft into a genome sequence with high accuracy and nearly complete coverage. Here, we report the result of this finishing process. The current genome sequence (Build 35) contains 2.85 billion nucleotides interrupted by only 341 gaps. It covers ∼99% of the euchromatic genome and is accurate to an error rate of ∼1 event per 100,000 bases. Many of the remaining euchromatic gaps are associated with segmental duplications and will require focused work with new methods. The near-complete sequence, the first for a vertebrate, greatly improves the precision of biological analyses of the human genome including studies of gene number, birth and death. Notably, the human enome seems to encode only 20,000-25,000 protein-coding genes. The genome sequence reported here should serve as a firm foundation for biomedical research in the decades ahead

Performance Analysis of Multihop Full-Duplex NOMA Systems with Imperfect Interference Cancellation and Near-Field Path-Loss

Outage probability (OP) and potential throughput (PT) of multihop full-duplex (FD) nonorthogonal multiple access (NOMA) systems are addressed in the present paper. More precisely, two metrics are derived in the closed-form expressions under the impact of both imperfect successive interference cancellation (SIC) and imperfect self-interference cancellation. Moreover, to model short transmission distance from the transmit and receive antennae at relays, the near-field path-loss is taken into consideration. Additionally, the impact of the total transmit power on the performance of these metrics is rigorously derived. Furthermore, the mathematical framework of the baseline systems is provided too. Computer-based simulations via the Monte Carlo method are given to verify the accuracy of the proposed framework, confirm our findings, and highlight the benefits of the proposed systems compared with the baseline one

An Ab Initio RRKM-Based Master Equation Study for Kinetics of OH-Initiated Oxidation of 2-Methyltetrahydrofuran and Its Implications in Kinetic Modeling

Cyclic ethers (CEs) can be promising future biofuel candidates. Most CEs possess physico-chemical and combustion indicators comparable to conventional fuels, making them suitable for internal combustion engines. This work computationally investigates the kinetic behaviors of hydrogen abstraction from 2-methyl tetrahydrofuran (2MTHF), one of the promising CEs, by hydroxyl radicals under combustion and atmospheric relevant conditions. The various reaction pathways were explored using the CCSD(T)/cc-pVTZ//M06-2X/aug-cc-pVTZ level of theory. The Rice–Ramsperger–Kassel–Marcus-based master equation (RRKM-ME) rate model, including treatments for hindered internal rotation and tunneling, was employed to describe time-dependent species profiles and pressure and temperature-dependent rate coefficients. Our kinetic model revealed that the H-abstraction proceeds via an addition-elimination mechanism forming reaction complexes at both the entrance and exit channels. Eight different reaction channels yielding five radical products were located. The reaction exhibited complex kinetics yielding a U-shaped Arrhenius behavior. An unusual occurrence of negative temperature dependence was observed at low temperatures, owing to the negative barrier height for the hydrogen abstraction reaction from the C-H bond at the vicinity of the O-atom. A shift in the reaction mechanism was observed with the dominance of the abstraction at Cα-H of 2MTHF ring (causing negative-T dependence) and at CH3 (positive-T dependence) at low and high temperatures, respectively. Interestingly, the pressure effect was observed at low temperatures, revealing the kinetic significance of the pre-reaction complex. Under atmospheric pressure, our theoretical rate coefficients showed excellent agreement with the available literature data. Our model nicely captured the negative temperature-dependent behaviors at low temperatures. Our predicted global rate coefficients can be expressed as k (T, 760 Torr) = 3.55 × 101 × T−4.72 × exp [−340.0 K/T] + 8.21 × 10−23 × T3.49 × exp [918.8 K/T] (cm3/molecule/s). Our work provides a detailed kinetic picture of the OH-initiated oxidation kinetics of 2MTHF. Hence, this information is useful for building a kinetic me chanism for methylated cyclic ethers

Perceived effects of COVID-19 restrictions on smallholder farmers: Evidence from seven lower- and middle-income countries

CONTEXT: The COVID-19 pandemic caused unprecedented global disruption and continues to wreak havoc. Dire predictions were made about the risks to smallholder farmers in lower- and middle- income, but hard data have been lacking. We present the results from 9201 interviews with smallholder farmers from seven countries. OBJECTIVE: The objectives are to describe: i) how farmers perceive the key effects of the COVID-19 pandemic and containment measures on livelihoods and food security; ii) the effects on agricultural activities; iii) the coping strategies households deployed. METHODS: Household surveys were conducted as part of ongoing monitoring programs during the latter half of 2020. Sites in seven countries were covered: Burundi; Kenya; Rwanda; Tanzania; Uganda; Zambia; and Vietnam. Findings are representative of smallholder farmers across multiple districts per country. RESULTS AND CONCLUSIONS: The effects of the COVID-19 containment measures were widespread and often perceived to be severe. Food purchase, off-farm income, sale of farm produce, and access to crop inputs were all affected. In locations under more stringent restrictions during the time of the survey, up to 80% of households had to reduce food consumption and/or variety. Almost all households with off-farm incomes reported reductions, by half on average. A half to three-quarters of households (depending on the location) with income from farm sales reported losses compared to the pre-pandemic situation. In locations with more relaxed containment measures in place during the time of the survey, less frequent and less severe economic and food security outcomes were perceived by the respondent, with around 20% of households reporting negative outcomes. Mobility restrictions, reduced market access, crashes in sale price for agricultural goods, and soaring prices for food purchase were key factors. Sale prices generally dropped for all agricultural products in any given location, and affected not only high-value perishable products, but also staple crops such as maize and cassava. Depending on the location, between 30% and 90% of the households applied coping strategies in response to the pandemic during 2020. There was an almost complete absence of official aid amongst households interviewed. SIGNIFICANCE: Our results raise the thorny issue of how best to balance containment of disease against the wellbeing of the vulnerable rural population in lower- and middle-income countries. There is a risk that the buffering capacity of rural people will become exhausted. Possible policy measures to limit negative outcomes include i) tiered mobility restrictions with travel allowed for economic reasons; ii) short-term price guarantee schemes to stabilise the food system; iii) direct aid; iv) the timely re-installation of distribution channels for agricultural inputs