The interpersonal communication behaviors of teachers have been substantiated to affect motivation, engagement, and success of students in the academic arena. Aiming to provide a systematic review of ...some teacher-related constructs in this domain, the present article was a bid to explain the crucial pillars of clarity, credibility, and immediacy of teachers in juxtaposition with theories and models of motivation and engagement of students. More particularly, this article presents some theoretical underpinnings to justify its claims using the ideas of positive psychology, the broaden-and-build theory, the rhetorical/relational goal theory, social cognitive theory, the attachment theory, some popular motivational theories, and the engagement theory. These theories signify the importance of clarity, credibility, and immediacy of teachers in the classroom and depict their association and impact on motivation and engagement of students. Later, the arguments are defended through a quick glance at the available empirical studies on each of the constructs. Afterward, the findings and implications of this review article are discussed. Finally, research gaps and future directions are presented for avid researchers to make new explorations.
Given the fact that students’ absence and disengagement are among the major challenges that teachers experience in educational contexts, investigating factors contributing to students’ academic ...engagement and willingness to attend classes is of high importance. These challenges are more common in English as a medium of instruction (EMI) classes wherein students are usually not skilled enough to participate in academic tasks and activities. Accordingly, the present study probed into the role of Chinese EMI teachers’ clarity and credibility in fostering students’ academic engagement and willingness to attend classes. In doing so, the E-version of Teacher Clarity Short Inventory, Source Credibility Scale, Utrecht Work Engagement Scale for Students, and Willingness to Attend Classes Questionnaire was virtually distributed among 832 Chinese college students. Performing correlational analyses, strong associations were found between teachers’ clarity and credibility and students’ academic engagement and willingness to attend classes. To assess the power of Chinese EMI teachers’ clarity and credibility in predicting students’ academic engagement and willingness to attend classes, structural equation modeling (SEM) was employed. The results of SEM analysis illuminated that both teacher clarity and credibility are strong predictors of students’ academic engagement and willingness to attend classes. The implications of the findings are also discussed.
Chitosan is a product of the deacetylation of chitin, which is widely found in nature. Chitosan is insoluble in water and most organic solvents, which seriously limits both its application scope and ...applicable fields. However, chitosan contains active functional groups that are liable to chemical reactions; thus, chitosan derivatives can be obtained through the chemical modification of chitosan. The modification of chitosan has been an important aspect of chitosan research, showing a better solubility, pH-sensitive targeting, an increased number of delivery systems, etc. This review summarizes the modification of chitosan by acylation, carboxylation, alkylation, and quaternization in order to improve the water solubility, pH sensitivity, and the targeting of chitosan derivatives. The applications of chitosan derivatives in the antibacterial, sustained slowly release, targeting, and delivery system fields are also described. Chitosan derivatives will have a large impact and show potential in biomedicine for the development of drugs in future.
Interorganellar cooperation maintained via exquisitely controlled retrograde-signaling pathways is an evolutionary necessity for maintenance of cellular homeostasis. This signaling feature has ...therefore attracted much research attention aimed at improving understanding of the nature of these communication signals, how the signals are sensed, and ultimately the mechanism by which they integrate targeted processes that collectively culminate in organellar cooperativity. The answers to these questions will provide insight into how retrograde-signal-mediated regulatory mechanisms are recruited and which biological processes are targeted, and will advance our understanding of how organisms balance metabolic investments in growth against adaptation to environmental stress. This review summarizes the present understanding of the nature and the functional complexity of retrograde signals as integrators of interorganellar communication and orchestrators of plant development, and offers a perspective on the future of this critical and dynamic area of research.
The next day, however, it proved to be an inflated report of the efficacy of the drug. ...all media reporting on public health issues, especially in major health crises, should base on reality ...without exaggeration and falsehood. ...we recommend that the public arrange reasonable time for reading news information. ...we suggested that the government or the news media industry organizations ban relating laws or regulations to regulate the news coverage, so as not to cause public panic and headline stress disorder in the event of a public emergency.
Air pollution constitutes a significant stimulus of asthma exacerbations; however, the impacts of exposure to major air pollutants on asthma-related hospital admissions and emergency room visits ...(ERVs) have not been fully determined.
We sought to quantify the associations between short-term exposure to air pollutants ozone (O3), carbon monoxide (CO), nitrogen dioxide (NO2), sulfur dioxide (SO2), and particulate matter ≤10 μm (PM10) and PM2.5 and the asthma-related emergency room visits (ERV) and hospitalizations.
Systematic computerized searches without language limitation were performed. Pooled relative risks (RRs) and 95% confidence intervals (95%CIs) were estimated using the random-effect models. Sensitivity analyses and subgroup analyses were also performed.
After screening of 246 studies, 87 were included in our analyses. Air pollutants were associated with significantly increased risks of asthma ERVs and hospitalizations O3: RR(95%CI), 1.009 (1.006, 1.011); I2 = 87.8%, population-attributable fraction (PAF) (95%CI): 0.8 (0.6, 1.1); CO: RR(95%CI), 1.045 (1.029, 1.061); I2 = 85.7%, PAF (95%CI): 4.3 (2.8, 5.7); NO2: RR(95%CI), 1.018 (1.014, 1.022); I2 = 87.6%, PAF (95%CI): 1.8 (1.4, 2.2); SO2: RR(95%CI), 1.011 (1.007, 1.015); I2 = 77.1%, PAF (95%CI): 1.1 (0.7, 1.5); PM10: RR(95%CI), 1.010 (1.008, 1.013); I2 = 69.1%, PAF (95%CI): 1.1 (0.8, 1.3); PM2.5: RR(95%CI), 1.023 (1.015, 1.031); I2 = 82.8%, PAF (95%CI): 2.3 (1.5, 3.1). Sensitivity analyses yielded compatible findings as compared with the overall analyses without publication bias. Stronger associations were found in hospitalized males, children and elderly patients in warm seasons with lag of 2 days or greater.
Short-term exposures to air pollutants account for increased risks of asthma-related ERVs and hospitalizations that constitute a considerable healthcare utilization and socioeconomic burden.
Optimizing advertising budget allocation in the luxury fashion industry is an important problem. In this study, motivated by real‐world practices, we consider a luxury fashion firm serving a ...conspicuous market consisting of two groups of consumers who influence one another. We investigate the optimal customer portfolios and budget allocation problem using the mean‐variance (MV) framework. Under the basic model in which all budget must be spent, we identify different scenarios and propose an algorithm to construct the MV efficient frontier for each scenario. Interestingly, different from the classic investment portfolio problem, we reveal that: (i) not all budget allocations between the two groups of consumers are MV efficient, which means that the efficient frontier is not continuous; (ii) in the presence of social influence, diversification of customer portfolio does not always lead to a smaller variance, which counterintuitively means that focusing on a single consumer group can reduce risk. We also prove that to maximize expected profit, the optimal strategy is to allocate all advertising budget to one group of consumers only (i.e., a polarized strategy). We illustrate analytically, the importance of identifying the right scenario for budget planning. Finally, we examine the budget saving strategy in the extended model and uncover that the respective range of efficient solutions is smaller than the one under the all budget spending strategy. This shows that the budget saving strategy offers less flexibility for MV efficient budget allocation than the all budget spending strategy.
Herein we disclose a scalable organocatalytic direct arylation approach for the regio- and atroposelective synthesis of non-C 2-symmetric 2,2′-dihydroxy-1,1′-binaphthalenes (BINOLs). In the presence ...of catalytic amounts of axially chiral phosphoric acids, phenols and naphthols are coupled with iminoquinones via a cascade process that involves sequential aminal formation, sigmatropic rearrangement, and rearomatization to afford enantiomerically enriched BINOL derivatives in good to excellent yields. Our studies suggest that the (local) symmetry of the initially formed aminal intermediate has a dramatic impact on the level of enantioinduction in the final product. Aminals with a plane of symmetry give rise to BINOL derivatives with significantly lower enantiomeric excess than unsymmetrical ones featuring a stereogenic center. Presumably asymmetric induction in the sigmatropic rearrangement step is significantly more challenging than during aminal formation. Sigmatropic rearrangement of the enantiomerically enriched aminal and subsequent rearomatization transfers the central chirality into axial chirality with high fidelity.
Electrical capacitance tomography (ECT) image reconstruction has developed decades and made great achievements, but there is still a need to find new theory framework to make image reconstruction ...results better and faster. Recent years, deep learning, which is based on different series of artificial neural networks good at mapping complicated nonlinear functions, is flourishing and adopted in many fields. In this paper, a supervised autoencoder neural network is proposed to solve the image reconstruction problem of ECT, which has an encoder network and a decoder network. A simulation-based data set consisting of 40 000 pairs of instances, of which each pair of sample has a capacitance vector and corresponding permittivity distribution vector, is used to train and test the performance of the autoencoder by 10-fold cross validation. Furthermore, data with artificial noise, data regarding flow pattern not in training data set, and experimental data from a practical ECT system, are used to test the generalization ability and practicability of the network, respectively. The preliminary results show that the proposed autoencoder-based image reconstruction algorithm for ECT is of providing better reconstruction results.
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