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Designing a multidimensional adaptive test (M-MST) based on a multidimensional item response theory (MIRT) model is critical to make full use of the advantages of both MST and MIRT in implementing multidimensional assessments. This study proposed two types of automated test assembly (ATA) algorithms and one set of routing rules that can facilitate the development of an M-MST. Different M-MST designs were developed based on the proposed ATA algorithms and routing rules and were evaluated through two sets of simulation studies. Study 1 used simulated item banks and considered a variety of testing factors, and results from which can inform us the theoretical performance of the proposed M-MST designs. Study 2 was designed based on a real multidimensional assessment. In addition, a MCAT was simulated as a baseline design to demonstrate the advantage of the proposed M-MST design in each study. Our simulation results indicate that the proposed ATA algorithms and routing rule can generate M-MSTs with a good-quality control and the same or even better ability estimation results than the MCAT given the same condition. This demonstrates the advantage of using M-MST for multidimensional assessment especially for the one that needs to satisfy many nonstatistical constraints.

In order to further optimize the performance of PMMA (Polymethyl Methacrylate) repair mortar. In this paper, fly ash, talcum powder and wollastonite powder are used as fillers to modify the PMMA repair mortar. The effects of these three fillers on the working performance, mechanical performance and durability of PMMA repair mortar were explored. The study shows that the three fillers have good effect on the bond strength of the repair mortar, in which the fly ash has the best effect on the mechanical performance. The mechanical properties of PMMA repair mortar were best when the amount of fly ash was 60 phr (parts per hundred, representing the amount of the material added per hundred parts of PMMA). At this time, the 28 d compressive strength was 71.26 MPa and the 28 d flexural strength was 28.09 MPa, which increased by 13.31% and 15.33%, respectively. Wollastonite powder had the least negative effect on the setting time of the PMMA repair mortar. When the dosage of wollastonite powder was increased to 100 phr, the setting time was only extended from 65 min to 94 min. When the talc dosage was 60 phr, the best improvement in salt freezing resistance was achieved. After 100 cycles of salt freezing, the mass loss rate and strength loss rate decreased to 0.159% and 4.97%, respectively, which were 75.1% and 37.7% higher than that of the control group. The addition of all three fillers reduced the porosity and the proportion of harmful pores in the mortar. This study contributes to a comprehensive understanding how different types of fillers affect PMMA repair mortars, and it also provides theoretical support for the further development of low-temperature rapid repair mortars. [ABSTRACT FROM AUTHOR]

Precisely estimating factor scores is challenging, especially when models are mis-specified. Stemming from network analysis, centrality measures offer an alternative approach to estimating the scores. Using a two-fold simulation design with varying availability of a priori theoretical knowledge, this study implemented hybrid centrality to estimate factor scores and compared the performance with traditional methods, where both proper and improper specifications were considered. In supervised scenarios, network scores using hybrid centrality performed similarly to CFA scores for correctly specified models. The network scores were more accurate when sample sizes were small or test reliability was low, and also demonstrated higher robustness under misspecification. In the second fold, network scores performed better than EFA scores when structure knowledge was unavailable, as the LoGo algorithm of network analysis demonstrated the best performance in retaining the correct factor structure. The results suggest that network analysis can be a better choice for factor score estimation under various conditions. [ABSTRACT FROM AUTHOR]

With the fast development of the cold chain transportation industry, the traditional refrigeration method results in significant energy consumption. To address the national call for energy saving and emission reduction, the search for a new type of energy storage material has already become a future development trend. According to the national standard GB/T28577 for the classification and basic requirements of cold chain logistics, the temperature in frozen logistics is typically below −18 °C. In this study, n-undecane with a phase change temperature of −26 °C is chosen as the core material of microcapsules. Poly(methyl methacrylate) is applied as the shell material, with n-undecane microcapsules being prepared through suspension polymerization for phase change cold storage materials (MEPCM). Using characterization techniques including SEM, DSC, FTIR, and laser particle size analysis, the effects of three types of emulsifiers (SMA, Tween-80, Tween-80/span-80 (70/30)), SMA emulsifier dosage, core–shell ratio, and emulsification rate on the thermal performance and micro-surface morphology of n-undecane/PMMA microcapsules were studied. The results indicate that when comparing SMA, Tween-80, and Tween-80/span-80 (70/30) as emulsifiers, the dodecane/PMMA microcapsules prepared with SMA emulsifier exhibit superior thermal performance and micro-surface morphology, possessing a complete core–shell structure. The optimal microstructure and the highest enthalpy of phase change, measuring 120.3 kJ/kg, are achieved when SMA is used as the emulsifier with a quantity of 7%, a core-to-wall ratio of 2.5:1, and an emulsification speed of 2000 rpm. After 200 hot and cold cycles, the enthalpy of phase change decreased by only 18.6 kJ/kg, indicating the MEPCM thermal performance and cycle life. In addition, these optimized microcapsules exhibit favorable microstructure, uniform particle size, and efficient energy storage, making them an excellent choice for the refrigeration and freezing sectors. [ABSTRACT FROM AUTHOR]

Surface‐enhanced Raman scattering (SERS) spectroscopy is an ultrasensitive detection technique for molecular identification in both biology and chemistry. 2D materials have displayed increasing potentials as SERS substrates based on chemical enhancement, where optimization of the band structure to promote the charge transfer is exceptionally important. Here, the regulation of band structure of 2D metal phosphorus trichalcogenides (MPCh3) via entropy engineering is demonstrated. The optimized high‐entropy MnFeCuAgInPS3 nanosheets (NSs) with narrowed bandgap (Eg) show significant SERS performance with a low detection limit with 10−9m for both rhodamine 6G and crystal violet. Combined spectral characterizations and density functional theory (DFT) calculations reveal that the combination of multiple hetero‐element provides continuous d orbitals and endows high‐entropy MPCh3 NSs with high population of electrons at the energies near Fermi level (EF), which allows highly efficient photo‐induced charge transfer (PICT) between the SERS substrates and target molecules. This work affords a new strategy for high‐performance 2D SERS materials and also reveals the origin of the band structure regulation by entropy engineering. [ABSTRACT FROM AUTHOR]

Aims: To evaluate the impact of a dual glucose‐dependent insulinotropic peptide (GIP) and glucagon‐like peptide‐1 (GLP‐1) receptor agonist tirzepatide (TZP), and its potential dose‐response effect, on heart rate. Methods: Articles were searched from PubMed, Web of Science, Embase, Cochrane Library, and clinical trials registries (ClinicalTrials.gov) databases. Randomized controlled trials (RCTs) comparing TZP at doses of 5, 10 and 15 mg in adults with type 2 diabetes were included. Six study arms were summarized from original research (TZP 5, 10 and 15 mg, GLP‐1 receptor agonists [GLP‐1RAs], insulin, placebo). The GLP‐1RA and non‐GLP‐1RA groups were combined to form a control group. Two reviewers independently extracted data and assessed the quality of each study. Mean differences (MDs) were calculated as effect estimates for continuous outcomes. Pairwise meta‐analyses and network meta‐analyses were conducted. The study protocol was prospectively registered (PROSPERO ID: CRD42023418551). Results: Eight articles were included in this systematic review and meta‐analysis. The mean baseline heart rate ranged from 65.2 to 75.7 beats per minute. Pairwise meta‐analysis showed that, compared with combined the control group, there were significantly greater increases in heart rates in the TZP group (MD 1.82, 95% confidence interval [CI] 0.75, 2.89). Similar significant rises were identified when comparing TZP with GLP‐1RAs and non‐GLP‐1RAs (GLP‐1 RAs: MD 2.29, 95% CI 1.00, 3.59; non‐GLP‐1RAs: MD 1.58, 95% CI 0.26, 2.91). TZP 5 mg was associated with smaller increases in heart rates compared to TZP 10 mg and TZP 15 mg (TZP 10 mg: MD −0.97, 95% CI −1.79, −0.14; TZP 15 mg: MD −2.57, 95% CI −3.79, −1.35). TZP 10 mg increased heart rate less than TZP 15 mg (MD −1.5, 95% CI −2.38, −0.82). Network meta‐analysis indicated that TZP 15 mg was associated with significant increases in heart rate compared with TZP 5 mg (MD 2.53, 95% CI 1.43, 3.62), TZP 10 mg (MD 1.44, 95% CI 0.35, 2.53), GLP‐1RAs (MD 3.46, 95% CI 1.67, 5.25), insulin (MD 2.86, 95% CI 1.32, 4.41) and placebo (MD 2.96, 95% CI 1.36, 4.57). Conclusions: Our study showed not only that there was a greater increase in heart rate in the TZP group than in the control, GLP‐1RA and non‐GLP‐1RA groups, but also that the 15‐mg dose of TZP had the strongest impact on increasing heart rates compared with the other five inventions, with a TZP dose‐response impact on heart rate. Further research on the effects of TZP treatment‐related increases in heart rate is required. [ABSTRACT FROM AUTHOR]