This study aimed to explore the indirect effects of appearance-related anxiety (ARA) on Instagram addiction (IA) through sequential mediators, namely social media activity intensity (SMAI) and Instagram feed dependency (IFD). The study also aimed to provide theoretical explanations for the observed relationships and contribute to the understanding of the complex interplay between appearance-related concerns, social media usage, and addictive behaviors in the context of IA. A sample of 306 participants was used for the analysis. The results of the sequential mediation analysis (SMA) revealed several important findings. Firstly, the mediation model demonstrated that SMAI mediated the relationship between ARA and IA. However, there was no direct relationship observed between ARA and SMAI. Secondly, the analysis showed that IFD acted as a second mediator in the relationship between ARA and IA. Both ARA and SMAI had significant direct effects on IA, indicating their individual contributions to addictive behaviors. Furthermore, the total effect model confirmed a positive relationship between ARA and IA. This finding suggests that ARA has a direct influence on the development of IA. The examination of indirect effects revealed that ARA indirectly influenced IA through the sequential mediators of SMAI, IFD, and ultimately IA itself. The completely standardized indirect effect of ARA on IA through these mediators was found to be significant. Overall, this study provides evidence for the indirect effects of ARA on IA and highlights the mediating roles of SMAI and IFD. These findings contribute to our understanding of the psychological mechanisms underlying the complex relationship between appearance-related concerns, social media usage, and the development of IA.

This research aims to examine the role of learning leadership on teacher performance in elementary schools, analyze the influence of digital literacy on teacher performance, analyze the role of emotional intelligence on teacher performance and analyze the role of intellectual intelligence on teacher performance. In this digital era, digital literacy plays an important role in education. The application of digital literacy in education is still not optimal and there is no previous research that discusses the variables of instructional leadership, teacher performance, digital literacy, emotional intelligence and intellectual intelligence. The research method used is quantitative, the population of this research is all teachers who have used e-learning methods, and the analysis of this research uses structural equation modelling (SEM), the respondents for this research are 675 Indonesian teachers. The sampling method is simple random sampling. Research data was obtained from distributing online questionnaires designed using a 5-point Likert scale, namely scale 1 is strongly disagree, scale 2 is disagree, scale 3 is neutral, scale 4 is agree and scale 5 is strongly agree. Data processing uses SmartPLS 3.0 software tools. The SEM test stages in this research are the outer model test, namely convergent validity, discriminant validity and composite reliability, and then the inner model test, namely hypothesis testing. The results of the analysis using SEM are that the Instructional leadership variable has a positive and significant relationship to teacher performance, the Digital literacy variable has a positive and significant relationship to teacher performance, the Emotional intelligence variable has a positive and significant relationship to teacher performance and Intellectual intelligence has a positive and significant relationship to teacher performance. The novelty of this research is the discovery of a model of the relationship between instructional leadership variables, digital literacy variables, emotional intelligence variables, and intellectual intelligence variables on teacher performance which did not exist in previous research studies. This research has a novelty, namely a model analyzed using SEM-PLS in the digital era. The principal must be able to determine and set learning objectives in his school, in his implementation the principal always involves teachers in developing and implementing learning goals and objectives and the principal also refers to the curriculum set by the government in developing learning. The dimensions of instructional leadership are defining school goals, managing learning programs, and creating a positive learning climate. In other words, the principal has implemented Instructional Leadership with indicators of setting learning goals, indicators of being a resource for staff, indicators of creating a school culture and climate that is conducive to learning, indicators of communicating the school’s vision and mission to staff, indicators of conditioning staff to achieve their goals.

Bioactive materials are those that cause a number of interactions at the biomaterial-living tissue inter-face that result in the evolution of a mechanically strong association between them. For this reason, an implantable material’s bioactive behavior is highly advantageous. Silicate glasses are encouraged to be used as bioactive glasses due to their great biocompatibility and beneficial biological effects. The sol-gel method is the most effective for preparing silicate glasses because it increases the material’s bioactivity by creating pores. Glass densities are altered by the internal network connectivity between network formers and network modifiers. The increase in the composition of alkali or alkaline oxides reduces the number of bridging oxygens and increases the number of non-bridging oxygens by retaining the overall charge neutrality between the alkali or alkaline cation and oxygen anion. Higher drying temperatures increase pore densities, while the melt-quenching approach encourages the creation of higher density glasses. Band assignments for the BAG structure can be explained in detail using Fourier Transform Infrared (FTIR) and Raman spectroscopic investigations. Raman spectroscopy makes it simple to measure the concentration of the non-bridging oxygens in the silica matrix.

The objective is to determine the impact of economic growth on the externalities of infrastructure investments for the Peruvian case for the periods from 2000 to 2022. The methodologies used are descriptive, explanatory and correlational, analyzing qualitative and mainly quantitative methods. Econometric software was used, and correlations of variables were created for each proposed hypothesis. The estimated model shows that all the independent variables have a significant t-statistic greater than 2 and a probability of less than 5%, which indicates that they are significant and explains the model. The R² is 98.02% which indicates that there is a high level of explanation by the independent variables to the LOG(RGDP). The results of the estimated models demonstrate the existence of a positive and significant relationship of investments in infrastructure and externalities on the growth of the non-deterministic component of real GDP, therefore, in a practical way, private and public investment has a positive effect on the non-deterministic growth of real GDP.

Micro-mobility has the potential to address first -mile challenges, improving transit accessibility and encouraging public transit usage. However, users’ acceptability of modal integration between various micro-mobility options and public transit remains largely unexplored in the literature. Our study investigates the user behavior for first-mile options, focusing on four alternatives: walking, bicycling, motorcycling, and bus, to access urban mass rapid transit (UMRT) in Hanoi, Vietnam. Based on data collected from 1380 individuals, a Nested Logit Model (NLM) was proposed to analyze the determinants of users’ acceptability under each access mode option as well as evaluate further impacts of shifts in access mode choice on vehicle-kilometer traveled and emissions. The analysis shows that the availability of access modes might increase UMRT use by 47.83%. While this increase further generates additional vehicle-kilometer traveled due to the increase in park-and-ride users, this is offset overall by the large number of motorcycle users shifting to UMRT. Under the most optimistic scenario, modal integration for transit-access trips leads to an average reduction of 17.7% in net vehicle-kilometer traveled or 14.5% in net CO₂ emissions or 10.9% in NO_x from private vehicles. Our findings also imply that the introduction of parking fees for bicycling- or motorcycling-access trips, while impactful, does not significantly change UMRT choice. Therefore, the pricing schemes should be a focus of parking planning surrounding stations. Finally, a number of policy suggestions for parking planning and first-mile vehicles are presented.