The proficiency of English teachers in accurately understanding their roles and employing diverse teaching skills is crucial for enhancing the quality of English instruction. This study utilizes the ...Rasch model, a component of the Item Response Theory (IRT), to develop assessment scales aimed at evaluating English teachers’ role orientation and teaching skill levels. We selected 267 English teachers from higher education institutions in X province as participants. The assessment instruments, designed around these scales, were disseminated via the Questionnaire Star platform and analyzed using Excel and SPSS software. This research examines the application of the Rasch model in assessing the role orientation and teaching skills of English teachers. It specifically investigates the scales’ unidimensionality, goodness of fit, and scoring quality across various levels. The results from the unidimensionality test of teachers’ role orientation skills yielded weighted fit values ranging from 0.90 to 0.97, with logit results for teachers’ role orientation skills spanning from -2.065 to 4.651. Furthermore, the loadings for teacher skill levels remained within the acceptable range of ±0.6. Interestingly, the discrepancy between the logit values of the strictest and most lenient teacher raters was significantly smaller (1.189 logits) compared to that of student raters, which was 2.562 logits. The findings suggest that employing the Rasch model to analyze English teachers’ role orientation and skill levels can significantly support the enhancement of teachers’ capability to grasp their educational roles and improve their teaching skills.
We investigate the pricing and reverse channel choice decision issues in a closed-loop supply chain, within which the original equipment manufacturer (OEM) sells the new and remanufactured products ...through a retailer, while collects used products (cores) via dual recycling channels. We consider that collection competition exists between the dual recycling channels and the OEM has three options (i.e., OEM and Retailer dual collecting model, Retailer and Third party dual collecting model and OEM and Third party dual collecting model) to choose for collecting cores. We analytically show that the ranking of certain optimal values among the three optional models are independent of the competition intensity. Our result also shows that the OEM and Retailer dual collecting model is the best option for the OEM regardless of the competition intensity. We further compare our work with the existing optimal results in Hong et al. (2013) and Savaskan et al. (2004) for managerial insights on reverse channel choice.
•Investigating the pricing and reverse channel choice decision issues in a closed-loop supply chain.•Considering the collection competition between the two reverse channels.•Systematically comparing three different dual reverse channels in the same model framework.
The long non-coding RNA PVT1 (lncRNA PVT1) has been reported to act as an oncogenic regulator of several cancers. However, its expression and function in gallbladder cancer (GBC) remain largely ...unknown.
In situ hybridization (ISH) and quantitative real-time PCR (qPCR) were performed to detect the expression of PVT1 and miR-143 in GBC tissues and cell lines. Immunohistochemistry (IHC) assays were performed to assess the expression of the hexokinase 2 (HK2) protein. The relationships among PVT1, miR-143 and HK2 were evaluated using dual-luciferase reporter, RNA immunoprecipitation (RIP) and biotin pull-down assays. The biological functions of PVT1, miR-143 and HK2 in GBC cells were explored with cell counting kit 8 (CCK-8), 5-ethynyl-20-deoxyuridine (EdU), colony formation, transwell, wound healing and glucose metabolism assays in vitro. For in vivo experiments, a xenograft model was used to investigate the effects of PVT1 and HK2 on GBC.
PVT1 was upregulated in GBC tissues and cells and was positively associated with malignancies and worse overall survival. PVT1 knockdown inhibited cell proliferation, migration, and invasion in vitro and restrained tumor growth in vivo. Further studies demonstrated that PVT1 positively regulated HK2 expression via its competing endogenous RNA (ceRNA) activity on miR-143. Additionally, HK2 expression and function were positively correlated with PVT1. Furthermore, we observed that the PVT1/miR-143/HK2 axis promoted cell proliferation and metastasis by regulating aerobic glucose metabolism in GBC cells.
The results of our study reveal a potential ceRNA regulatory pathway in which PVT1 modulates HK2 expression by competitively binding to endogenous miR-143 in GBC cells, which may provide new insights into novel molecular therapeutic targets for GBC.
Emerging evidence indicates that gene expression in higher organisms is regulated by RNA polymerase II stalling during early transcription elongation. To probe the mechanisms responsible for this ...regulation, we developed methods to isolate and characterize short RNAs derived from stalled RNA polymerase II in Drosophila cells. Significant levels of these short RNAs were generated from more than one-third of all genes, indicating that promoter-proximal stalling is a general feature of early polymerase elongation. Nucleotide composition of the initially transcribed sequence played an important role in promoting transcriptional stalling by rendering polymerase elongation complexes highly susceptible to backtracking and arrest. These results indicate that the intrinsic efficiency of early elongation can greatly affect gene expression.
This paper develops a model to study channel coordination and risk sharing in a retailer-led supply chain. Such chains are characterized by a dominant retailer who aims to coordinate the upstream ...production quantity. We investigate a coordinating contract based on an option with two parameters. An option price is paid by the retailer for each additional unit of product reserved beyond the initial order. An exercise price serves as the unit purchasing price when the retailer sets a second order if realized demand is more than the initial order. A successful coordination needs two conditions. One condition is to maintain a negative correlation between exercise price and option price. Particularly, we draw the functional form. The other is that the firm commitment must be lower than the optimal production quantity in a centralized system. In a risk sharing mechanism, we prove that such a contract brings benefit to each party.
A novel dummy molecularly imprinted polymers (DMIPs) for aminoglycoside antibiotics (AAs) was prepared for the first time by precipitation polymerization using raffinose as template molecule, ...methacrylic acid as functional monomer and trimethylolpropane triacrylate as cross-linker. The obtained DMIPs were characterized in detail, and their adsorbing and recognition performance were evaluated. The results showed that the DMIPs exhibited specific recognition towards six AAs with large adsorption capacity. The dummy molecularly imprinted solid phase extraction (DMISPE) conditions including elution/washing solutions and sample loading volumes were optimized. Under optimum conditions, a convenient and efficient method for the determination of AAs in environmental water samples based on DMISPE coupling with hydrophilic interaction-high performance liquid chromatography-tandem mass spectrometry was established. The developed method showed good linearity with correlation coefficients higher than 0.9921 for all the analytes and good recoveries (70.8–108.3%) with relative standard deviations from 2.6 to 11.4% spiked at three different concentration levels in water samples. The limit of detection (S/N = 3) ranged from 0.006 to 0.6 ng/mL. The results demonstrated good potential of DMIPs for sample pretreatment of trace AAs in environmental water samples.
Schematic illustration of the synthetic process of dummy molecularly imprinted polymers for determination of aminoglycoside antibiotics in environmental water samples. Display omitted
•Dummy molecularly imprinted polymers (DMIPs) for aminoglycoside antibiotics was prepared.•Raffinose was used as the dummy template for synthesizing polymers.•DMISPE coupled with HILIC-LC-MS/MS method was developed for analysis of aminoglycoside antibiotics.•The developed method was simple and sensitive.
In this study, the effect of lithium slag (LS) on the frost resistance of cement-soil was evaluated. The results of freeze−thaw damage on the surface of the cement-soil, freeze−thaw mass loss, ...unconfined compression strength, triaxial shear strength, cohesion, and internal friction angle were tested at various freeze−thaw cycles after 90 days of curing when LS was incorporated into the cement-soil at different proportions (0%, 6%, 12%, and 18%). Combining nuclear magnetic resonance (NMR) T2 distribution and scanning electron microscopy (SEM) microscopic images, the mechanism of the effect of LS on the cement-soil was also analyzed. The experiment confirmed that the surface freeze−thaw damage degree and mass loss value of the cement-soil decreased after incorporating different LS contents, and that the unconfined compression strength, triaxial shear strength, cohesion, and internal friction angle also improved significantly compared with the specimens without LS. In this experiment, the optimization level of the cement-soil performance with different LS content was ranked as 12% > 18% > 6% > 0%. According to the NMR and SEM analysis results, the LS content of 12% can optimize the internal pore structure of the cement-soil and strengthen the bond between aggregate particles, hence inhibiting the extension of freeze-swelling cracks induced by freeze−thaw cycles. In conclusion, LS can effectively enhance the frost resistance of cement-soil, and the optimum content in this experiment is 12%.
The accumulation of lipid droplets (LDs) in hepatocytes is the main pathogenesis in nonalcoholic fatty liver disease (NAFLD), which is also the key risk factor for the progression of hepatocellular ...carcinoma (HCC). LDs behaviors are demonstrated to be associated with HCC advancement, and are tightly regulated by a subset protein localized on the surface of LDs. However, the role of LDs-localized protein in HCC has been rarely investigated. This study is focused on the transcriptional dynamic and prognostic value of LDs-localized protein in HCC. Firstly, we summarized the known LDs-localized proteins, which are demonstrated by immunofluorescence according to previous studies. Next, by the use of GEPIA/UALCAN/The Human Protein Atlas databases, we screened the transcriptional change in tumor and normal liver tissues, and found that 13 LDs-localized proteins may involve in the progression of HCC. Then we verified the transcriptional changes of 13 LDs-localized proteins by the use of HCC samples. Moreover, based on the assays of fatty liver of mice and human NAFLD liver samples, we found that the hepatic steatosis mainly contributed to the transcriptional change of selected LDs-localized proteins, indicating the involvement of these LDs-localized proteins in the negative role of NAFLD in HCC progression. Finally, we focused on the role of PLIN3 in HCC, and revealed that NAFLD status significantly promoted PLIN3 transcription in HCC tissue. Functional studies revealed that PLIN3 knockdown significantly limited the migration and chemosensitivity of hepatoma cells, suggesting the positive role of PLIN3 in HCC progression. Our study not only revealed the transcriptional change and prognostic value of lipid droplet-localized proteins in HCC, but also built the correlation between HCC and hepatic steatosis.
A salt crystal-templating synthesis route is proposed to synthesize a Fe-N-C catalyst with well-controlled mesoporous structure. In the presence of glucose, NaCl-template can efficiently tune the ...porous structure of catalyst and help to improve the oxygen reduction reaction (ORR) activity. The optimized catalyst possesses a hierarchical mesopore size distribution, a high Brunauer-Emmett-Teller surface area (up to 911.56 m2 g−1) and homogeneous distribution of abundant active sites. As a result, the obtained catalyst shows a desirable ORR activity in alkaline medium (half-wave potential of 0.84 V and kinetic mass activity at 0.8 V of 24.95 A g−1), high selectivity (electron transfer number >3.92), excellent long term durability (only 16 mV negative shift of half-wave potential after 5000 potential cycles in O2-saturated 0.1 M KOH) and good tolerance to methanol. The enhanced electrochemical performance enables the proposed catalyst to be the promising electrocatalyst candidate to commercial Pt/C towards ORR.
A 3D hierarchical mesoporous Fe-C-N catalyst with a large surface area was proposed as efficient electrocatalysts for oxygen reduction reaction by an eco-friendly and facile “salt crystal-templating” synthesis route. Display omitted
•A 3D hierarchical porous Fe-N-C catalyst is synthesized by an eco-friendly route.•Catalysts show a large specific area (911.56 m2 g−1) and abundant active sites.•Hierarchical porous structure efficiently facilitates mass transfer during ORR.•As-prepared catalyst shows excellent ORR activity and stability in alkaline media.
Percutaneous ablation has quickly arisen as one of the important alternative treatments for hepatocellular carcinoma (HCC). We aimed to compare the therapeutic effects of radiofrequency ablation ...(RFA) and other ablative techniques on HCCs.
Databases were searched to identify literature on complete tumor ablation (CTA), overall survival (OS), local tumor recurrence (LTR), and complications of RFA in the treatment of HCC, compared with those of microwave ablation (MWA), percutaneous ethanol injection (PEI), PEI plus RFA, cryoablation (CRA), laser ablation (LSA), and high-intensity focused ultrasound. Randomized controlled trials and high-quality cohort studies were included in the assessment.
The effects of MWA and CRA appeared to be similar to those of RFA, but lower rates of LTR and higher rates of CTA in large tumors compared with RFA were reported (P < 0.05). CTA rates were lower in patients treated with PEI (odds ratio OR 0.16, 95% confidence interval CI 0.06-0.42), and higher in those treated with PEI plus RFA (OR 2.28, 95% CI 1.19-3.60), with an increased incidence of fever (P < 0.05). LSA resulted in lower CTA rates (OR 0.32, 95% CI 0.13-0.81) and OS (hazard ratio 1.47, 95% CI 1.01-2.15), with a lower incidence of complications.
Compared with RFA, identical effects were found in MWA and CRA groups. Fewer complications were observed in PEI and LSA group. PEI plus RFA appeared more effective, with a higher rate of complications. Well-designed randomized controlled trials are further needed to confirm above results.