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Critical thinking is one of the core twenty-first century skills. This study designs the strategy of peer assessment based on the theory of knowledge building to improve a class of 33 undergraduate students' critical thinking skills in one semester. The context of knowledge building has four phases--idea generation, idea connection, idea improvement, and rising above--which are iterated by three rounds of peer assessment. In this study, the dependent variable was critical thinking skills, and the independent variable was peer assessment. Data sources include critical thinking skills surveyed, peer comments on Knowledge Forum and grades scored by students. The results showed that (1) students' critical thinking skills were significantly improved; (2) students' reports have risen in peer assessment; and (3) students' critical thinking skills are significantly correlated with peer assessment in the knowledge-building community with both peer comments and peer grades. The findings indicated that knowledge building created a positive culture for the promotion of critical thinking skills, comments that expressed strong disagreement could improve students' critical thinking skills, and the formation of community knowledge played a substantial role in promoting students' critical thinking skills.

The asymmetric construction of a quaternary fluorine‐containing stereogenic carboncenter is highly valuable for the development of fluoroine‐containing bioactive molecules. Herein, a base‐promoted, diastereoselective Mannich‐type reaction of 2‐aryloxy‐2‐fluoroketones with N‐(tert‐butylsulfinyl)imines has been developed. A number of the addition products featuring a fluorinated quaternary stereocarbon centre and a β‐fluoroamine structural motif have been readily obtained in good yields with moderate to good diastereoselectivities. The absolute configuration of the major diasteromer was determined by X‐ray crystallography analysis, and a closed transition‐state mode was proposed to explain the stereochemical outcome of this reaction. In addition, the addition product was efficiently converted into a α‑fluoro‐β‐amino alcohol through desulfinylation followed by reduction of the carbonyl group. [ABSTRACT FROM AUTHOR]

Rock slopes with layered fractured structure are widely distributed in the mountainous areas of Southwest China. Under earthquake, these slopes are highly susceptible to disasters such as collapse, landslides, etc., adversely impacting the operation safety of transportation systems. This study aims to investigate the difference in seismic behaviors of two types of fractured rock slopes with typical dipping and anti-dipping layered structures. To do so, two sets of large-scale shaking table tests on the two typical fractured rock slopes were performed. The emphasis was made on the different failure mechanism of these slopes tested when subjected to four different seismic loadings with step-wise increase in amplitudes up to 0.7 g. We observed a three-stage destabilization process in both cases. For the dipping slope, the initial formation of microcracks and then their rapid development was followed by generation of terraced sliding surface through slope, whereas the formation of microcracks was followed by toppling of rock front until final collapse for the anti-dipping slope. Both slopes exhibit elevation amplification effects upon seismic loads as previously observed in other studies of similar slopes. The acceleration amplification effects near the bedrock interface and within slopes are more significant in the dipping case compared to the anti-dipping one. These effects are much enhanced at the top of slopes considered when the peak input acceleration exceeds 0.4 g. Further, Hilbert marginal spectrum analysis indicates that a sliding failure surface above the midslope was formed for the dipping slope, whereas the anti-dipping slope experienced more severe damages at the slope shoulder. The outcomes of this study are of important potential to assist the risk assessment and early warning of seismic hazards of fractured rock slopes. [ABSTRACT FROM AUTHOR]

Purpose: The present study aimed to further examine the factor structure and measurement invariance of the UDRQ among a sample of Hungarian university students. Methods: Firstly, the factor structure of the UDRQ was examined among 837 Hungarian university students. Specifically, two measurement models (firstorder model and second-order model) were constructed and compared. Secondly, the internal consistency reliability of the UDRQ was examined. Thirdly, measurement invariance of the UDRQ was evaluated across genders. Finally, measurement invariance of the UDRQ was evaluated across two different samples. Results: It was found that the first-order model outperformed the secondorder model and better represented the factor structure of the UDRQ subscales. Results of Cronbach's alpha and Composite Reliability suggested that the internal consistency reliabilities of the two UDRQ subscales were satisfactory. Measurement invariance analysis revealed that the UDRQ measurement model was strict invariant across genders and samples. Conclusion: The findings of the present study indicated that the UDRQ displayed satisfactory reliability and validity and could be used to assess demands and resources of Hungarian university students. [ABSTRACT FROM AUTHOR]

The herringbone gear planetary transmission system (HGPTS) is a common component in the gearbox of wind turbines. Studying the dynamic performance of gear systems is the key to improving their stability. To reveal the influence of cracks on the dynamic characteristics of the HGPTS, using slicing method, we explore the influence of different crack factors on the time-varying meshing stiffness (TVMS) of the system. A 55-degrees of freedom bending torsion axis pendulum dynamic model was constructed using the centralized mass parameter method; in the model, factors such as TVMS of cracks as well as receding groove and errors are considered. The Runge–Kutta method was used to solve the dynamics, and the evolution diagram of the vibration and load distribution characteristics of the system under crack changes was obtained. Vibration tests were conducted on the system studied in this work. The results show that under the influence of cracks, the TVMS of the external and internal meshing pairs of the system will decrease, and as the cracks intensify, the fluctuation of the TVMS will decrease. Cracks can lead to regular impact behavior in the system. A modulation sideband centered on the meshing frequency appears in the vibration response, and the vibration trajectory of the gears will also become disordered, at the same time, under the influence of cracks, there are significant excitation factors in the load-sharing characteristics of the system. As the cracks continue to intensify, the vibration of the system becomes increasingly evident, and the load-sharing characteristics show a trend of first decreasing and then increasing. The vibration test results are in good agreement with the theoretical predictions. The correctness of the established model is verified. The research results can provide reference for the reliability research of wind turbine HGPTS. [ABSTRACT FROM AUTHOR]

The highly localized Fe d orbital in ion phthalocyanine (FePc)-based molecular catalysts significantly hinders their electrocatalytic nitrogen reduction reaction (eNRR) performance. Herein, we theoretically designed a series of FePc-based molecules with adjacent metal phthalocyanine sites to form an asymmetric delocalized electronic structure on Fe centers, promoting the catalytic activity and lowering the overpotential of the eNRR, as well as suppressing the hydrogen evolution reaction (HER) side reaction. [ABSTRACT FROM AUTHOR]

The current study presents the development process and initial validation of the Engagement in Athletic Training Scale (EATS), which was designed to evaluate athletes' engagement in athletic training. In study 1, item generation and initial content validity of the EATS were achieved. In study 2, the factor structure of the EATS was examined using exploratory factor analysis (EFA) and exploratory structural equation modeling (ESEM). Internal consistency reliabilities of the subscales were examined (N = 460). In study 3, factor structure, discriminant validity, internal consistency reliability, and nomological validity of the EATS were further examined in an independent sample (N = 513). Meanwhile, measurement invariance of the EATS across samples (study 2 and study 3) and genders was evaluated. Overall, results from the 3 rigorous studies provided initial psychometric evidence for the 19-item EATS and suggested that the EATS could be used as a valid and reliable measure to evaluate athletes' engagement in athletic training. [ABSTRACT FROM AUTHOR]