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Direct ink writing provides a new method for ceramic material forming. The single-screw extruder is used here to extrude viscous SiC slurry. Because the flow mechanism of ceramic slurry in the slurry direct writing extrusion device is unclear, lattice Boltzmann method (LBM) is used to analyze the flow process of ceramic slurry in the extrusion device. In this study, three different types of special-shaped, single-screw extruders (constant depth variable pitch screw, variable depth constant pitch screw, and variable depth variable pitch screw) are investigated to explore the effects of the shapes on the flow process. Compared with the traditional single-screw extruder, more attention should be paid to the difference in the flow channel. The non-Newtonian rheological model of SiC slurry is built, then the LBM for the non-Newtonian slurry is introduced and used to conduct the simulations based on the aforementioned three different cases. The results show that the effect of constant depth and variable pitch screw on the flow of ceramic slurry is the least and the flow of ceramic slurry in variable depth and variable pitch screw is the most complex.

Public school teachers retire much earlier than comparable professionals. Pension rule changes affecting new teachers can be used to close this gap in the long run, but any effects will not be observed for decades and the implications for workforce quality are unclear. This paper considers targeted incentive policies designed to deter retirement among senior, experienced high-need science and math teachers, as a policy to staff classrooms with qualified teachers and improve workforce quality. We use structural estimates from a dynamic retirement model to simulate the workforce effects of targeted late-career salary bonuses and deferred retirement plans (DROPs) using administrative data from Missouri. Although both policies produce additional teaching years at relatively low costs, by forcing teachers to reveal work-retirement preferences, DROPs generally yield incremental teacher years at lower cost per year. More generally, this work highlights the utility of using structural retirement models to analyze fiscal and workforce effects of changes to public sector pension plans, since the effects of pension rule changes cumulate over many years.

Diabetes remains a critical global public health challenge, posing a growing threat to human health and well-being. White tea is a lightly fermented tea and one of the six traditional tea categories in China. Owing to its rich content of bioactive compounds such as catechins and alkaloids, it has demonstrated potential anti-diabetic properties. However, its precise bioactive components, mechanisms of action, and relevant molecular targets require further investigation. In this study, an integrated approach combining polyphenol-targeted metabolomics, in vitro antioxidant assays, α-glucosidase inhibition tests, network pharmacology analysis, GEO database exploration, molecular docking, and molecular dynamics simulations was employed to identify the potential anti-diabetic compounds, targets, and mechanisms of white tea. The findings revealed that white tea is particularly abundant in 10 bioactive compounds, including epigallocatechin gallate, epicatechin gallate, and catechin, all of which exhibit significant anti-diabetic potential. These compounds were found to exert their effects by interacting with core molecular targets, namely cathepsin V (CTSV) and nucleotide-binding oligomerization domain-containing protein 1 (NOD1), and engaging in pathways related to signal transduction, apoptosis, and immune responses. This study establishes a strong theoretical basis for advancing white tea research and underscores new opportunities for applying natural products in diabetes therapy. [ABSTRACT FROM AUTHOR]

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The cytotoxic T lymphocyte-associated antigen-4 (CTLA4) gene, a member of the immunoglobulin superfamily, is crucial for maintaining immune homeostasis and preventing autoimmune diseases. Studies have shown that polymorphisms in the CTLA4 gene are linked to an increased risk of brucellosis in humans, but its association with brucellosis in goats remains unexplored. In this study, the tissue expression profile of CTLA4 in goats was investigated, and the correlation between InDel polymorphisms in the CTLA4 gene and susceptibility to brucellosis in goats was examined. The findings reveal the widespread expression of CTLA4 in goat tissues, particularly in the spleen and testes. The tested goat populations presented genotypes insertion/insertion (II), insertion/deletion (ID), and deletion/deletion (DD) at both the P1 and P2 loci, and an association analysis revealed significant differences in the distribution of genotypes and allele frequencies at the P1 and P2 loci of the CTLA4 gene between the Brucella goat case and the control groups (p < 0.05). Specifically, compared with the II genotype, the P1 and P2 loci were significantly associated with an elevated risk of brucellosis development in goats under both the codominant (ID/II) and dominant (ID + DD/II) models (P1, p = 0.042, p = 0.016; P2, p = 0.011, p = 0.014). Additionally, haplotype analysis indicated that haplotypes IP1DP2, DP1IP2, and DP1DP2 were significantly associated with an increased risk of brucellosis in goats compared to the reference haplotype IP1IP2 (p = 0.029, p = 0.012, p = 0.034). Importantly, the Lipopolysaccharide (LPS) stimulation of peripheral blood monocytes and/or macrophages from goats with the II, ID, and DD genotypes resulted in increased CTLA4 expression levels in the II genotype, leading to a robust LPS-induced inflammatory response. Through bioinformatic analysis, the observed effect of the InDel locus on Brucella pathogenesis risk in goats could be attributed to the differential binding of the transcription factors nuclear factor kappaB (NF-κB) and CCAAT/enhancer-binding protein α (C/EBPα). These findings offer potential insights for breeding strategies against brucellosis. [ABSTRACT FROM AUTHOR]

The Layer‐by‐Layer (LbL) strategy has emerged as a highly effective approach for enhancing the performance of organic photovoltaics (OPVs), notably boosting light harvesting and fill factor through spectral complementarity and morphology optimization. Crucially, the LbL processing strategy has been found to mitigate or overcome the decline in power conversion efficiency (PCE) during high‐speed blade coating. Despite these advancements, there remains a scarcity of research into the film‐formation process and the corresponding control strategies in high‐speed printing. A novel synergistic concentration‐temperature gradient control (SCTGC) strategy aimed at achieving high‐performance LbL‐type active layers at ultra‐fast coating speeds. This investigation reveals that both baseplate temperature and solution concentration exert a nonmonotonic regulatory influence on PCEs. Fine‐tuning the concentration gradient proves instrumental in balancing microfluidic competition within the wet film, thereby facilitating stable mass transport during the film formation process, and enhancing the high‐speed processability of the relevant OPV system. Additionally, the variations in crystallization kinetics under different temperatures are monitored. This work sheds light on the coating mechanism and film formation in high‐speed coating, highlighting the efficiency of the SCTGC method. [ABSTRACT FROM AUTHOR]

Morphology modulation and heterojunction construction are two efficacious strategies for developing high-performance gas sensors using metal oxide semiconductors. This study proposes a hierarchical MgO/Co3O4/ZnO hybrid structure for conductometric ethylene glycol gas sensing, achieved by fine-tuning the Co/Zn proportions in p–n heterojunction composites. The constructed ethylene glycol gas sensor, based on the hierarchical MgO/Co3O4/ZnO heterostructure, exhibits exceptional gas sensing capabilities with a Co/Zn feeding molar ratio of 4:1, manifesting a maximum response of 7.8–50 ppm of ethylene glycol at 125 °C. The noteworthy augmentation in ethylene glycol sensing performance is attributed to the synergistic effects of both n–n and p–n heterojunctions, along with the maximized surface area derived from the optimized feeding molar ratio of Co/Zn. The discerned findings of this study are poised to stimulate the innovation of prospective sensing materials for high-performance gas sensors. [ABSTRACT FROM AUTHOR]

The laying process is crucial in using stereolithography (SL) for molding Al2O3 parts. However, most studies focus on the laying process of macroscopic slurry; there needs to be more focus on microscopic exploration. Studying from a microscopic perspective can help us understand the influence of its parameters on droplet spreading and infer the macroscopic changes of the slurry based on the changes in droplet spreading to understand why parameters cause macroscopic changes in the slurry. A pseudopotential model based on Sisko's non-Newtonian behavior in lattice Boltzmann method is proposed to study the spreading process of droplets and validated using wetting characteristics. The previous layers of the platform and the printed solid are investigated to understand the effect of laying velocity on the spreading diameter, the thickness, and the both-sided contact angles. The results indicate that a higher laying velocity leads to a larger spreading diameter, a smaller spreading thickness, and a smaller left contact angle. However, it also increases the contact angle difference between the two sides, leading to uneven slurry. The droplet spreads more unevenly when the previous laying surface is the printed solid. At the same velocity, the droplet spreads with a smaller diameter, thicker thickness, and larger contact angle on the printed solid surface. Therefore, a higher laying velocity in the SL laying process is not recommended, especially when the front layer is a printed solid. Although a higher laying velocity will increase the laying area and reduce laying time, it will cause protrusions at the front edge, and inconsistent laying thickness of the same layer will affect the following photosensitive curing process. The Harris Hawks optimization-generalized regression neural network algorithm is proposed and compared with other common artificial intelligence algorithms to predict the spreading parameters. The comparison shows that the proposed algorithm provides a more stable and accurate prediction of spreading parameters. [ABSTRACT FROM AUTHOR]

Geometric errors are the key error sources that affect the machining quality of a five-axis machine tool. In the case of a non-orthogonal five-axis machine tool (NOFAMT), the modelling and compensation of geometric errors can be quite complex. This paper proposes a simplified modelling algorithm to derive the analytical expressions for the position-independent geometric error (PIGE) compensation of a NOFAMT without generating higher-order error terms. First, the geometric error modelling was conducted based on the homogeneous transformation matrix (HTM). Then, algebraic expressions for PIGE compensation were obtained according to the actual inverse kinematics and a simplified algorithm. By using the simplified algorithm, the efficiency of deriving algebraic expressions for geometric error compensation can be greatly enhanced. The PIGE compensation's numerical control (NC) codes can be directly computed using these algebraic expressions. Finally, the effectiveness and efficiency of the new algorithm were verified by numerical analysis and virtual machining. The detailed results were compared with those obtained using the differential method, and both sets of results showed the same trend. [ABSTRACT FROM AUTHOR]

The research constructs a theoretical framework including the relationship between the interaction of corporate environmental responsibility and technological base and firm performance and the mediating role of knowledge recombination. The research empirically studies the proposed framework by using the data of 258 firms listed on the Shanghai and Shenzhen Stock Exchanges from 2008 to 2019. The results show that the interaction between corporate environmental responsibility and technological base has a positive effect on firm performance and both the two dimensions of knowledge recombination that are knowledge recombination reuse and knowledge recombination creation could mediate this relationship. These results not only figure out the interaction between corporate environmental responsibility and technological base and its influencing mechanisms on firm performance, which is knowledge recombination and further broaden the application of the knowledge‐based view, but also provide important managerial implications for firms to acquire superior performance through corporate environmental responsibility and technological base. [ABSTRACT FROM AUTHOR]

Ceramic slurry is the raw material used in stereolithography, and its performance determines the printing quality. Rheological behavior, one of the most important physical factors in stereolithography, is critical in ceramic printing, significantly affecting the flow, spreading, and printing processes. The rheological behavior of SiO2 slurry used in stereolithography technology is investigated in the current research using different powder diameters and temperatures. The results present the apparent non-Newtonian behavior. The yielding characteristics occur in all cases. For single-powder cases, the viscosity decreases when the powder diameter is increased. When the nano-sized and micro-sized powders are mixed in different proportions, a more significant proportion of micron-sized powders will decrease the viscosity. With an increase in the nano-sized powders, the slurry exhibits the shear thinning behavior; otherwise, the shear thickening behavior is observed. Thus, the prediction model is built based on the use of the pelican optimization algorithm-deep extreme learning machine (POA-DELM), and the model in then compared with the fitted and traditional models to validate the effectiveness of the method. A more accurate viscosity prediction model will contribute to better fluid dynamic simulation in future work. [ABSTRACT FROM AUTHOR]