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Employing a 2-phenylfuro[2,3-b]quinoxaline (FQ) scaffold as a fluorophore, and phenyl, biphenyl, anthracene, and benzothiadiazole units as π-linkers, the four compounds Ph-dFQ, bPh-dFQ, ADN-dFQ and Bth-dFQ were respectively constructed, along with BIZ-FQ with a benzimidazole unit, to screen suitable blue emitters. When the linker was changed from phenyl to biphenyl, benzothiadiazole, or anthracene, the torsion angle between the FQ and linker increased from 29.7° to up to 80.0° due to their steric interaction. Owing to the large bulk and π-conjugation length of the anthracene linker, the torsion angle of 80.0° was predicted from theoretical calculations for ADN-dFQ, and as a result, multiple-wavelength emission is possible. ADN-dFQ and Bth-dFQ provided green emission due to clear charge-transfer emission but low fluorescence efficiency because the large torsion angles would prompt more energy dissipation from the S1 state and weaken its transition probabilities. Furthermore, despite the weak electron-donating capability of the phenyl, biphenyl and anthracene π-linkers, a charge-transfer state could be clearly formed with the electron-deficient FQ unit, and as a result, sky-blue to green emissions were observed for the three compounds Ph-dFQ, bPh-dFQ and ADN-dFQ. In addition, it was found that the five compounds could form an exciplex with 2-methyl-9,10-di(2-naphthyl)anthracene (MADN), and thus, when the five compounds were doped into a MADN host, the corresponding OLEDs mainly presented a green emission (∼496 nm) from the exciplex. [ABSTRACT FROM AUTHOR]

In blast furnace smelting with high-alumina ore, the permeability of high-alumina slag affects operational stability. The viscosity of the melt is a critical determinant of slag permeability. However, the viscosity behaviour and structural characteristics of high-alumina slag melts containing FeO remain insufficiently understood. In this study, the rotating cylinder method and Raman spectroscopy were employed to investigate the effects of the FeO content (5–20 mass pct) and w(CaO)/w(SiO2) (C/S, 1.2–1.6) on the viscosity and structural properties of a CaO-7 mass pct MgO-15 mass pct Al2O3–SiO2–FeO high-alumina slag melt. The experimental results show that the melt viscosity decreased with increasing FeO content and C/S ratio (from 1.2 to 1.4). However, when C/S was increased to 1.6, the viscosity initially increased and then decreased. The flow activation energy decreased with increasing FeO content and C/S. The thermal stability of the melt improved with higher FeO content, whereas it initially decreased and then increased with an increase in C/S. Raman spectroscopy results suggest that the viscosity reduction was primarily caused by the depolymerisation of silicate structures, involving the transformation of Q2 into Q1 and Q0, which led to an increase in the NBO/Si ratio. Increasing C/S from 1.4 to 1.5 caused an abnormal increase in viscosity, which can be attributed to the effect of ion arrangement densification outweighing that of silicate network depolymerisation. This study enhances the understanding of viscosity behaviour in high-alumina slag melts, providing a theoretical basis for the smelting of high-alumina ores. [ABSTRACT FROM AUTHOR]

Understanding the shrinkage behavior of iron ore is crucial for achieving blast furnace (BF) operating efficiency and reducing fuel ratio. This study presents high-temperature reduction load experiments on iron ore, simulating BF conditions. Two new shrinkage behavior models (SAEM-PC and SAEM-S&M) were established by combining the effects of temperature and reduction. These models describe the dynamic relationships between the temperature, reduction degree, and the physical properties of iron ore such as density and apparent viscosity during the reduction process. The activation energies ( E PC for the PC stage and E SM for the S&M stage) were determined to range from 79.95 to 42.69 kJ/mol and from 68.74 to 2.51 kJ/mol, respectively. The E PC demonstrates a gradual decrease, indicating a weakening of contraction resistance with temperature rise and reduction progress, while E SM exhibits fluctuations due to the interplay between the formation of liquid slag and the generation of solid sponge iron. The predictive accuracy of the model is substantiated by its average deviations. This study can deepen the understanding of the shrinkage mechanism of iron ore, which is of great significance for enhancing energy efficiency and reducing emissions in the steel industry., Competing Interests: The authors declare no competing financial interest., (© 2024 The Authors. Published by American Chemical Society.)

Herein, a Y-type compound ( 67dMeOTPA-FQ ) and a T-type compound ( 58dMeOTPA-FQ ) based on furo[2,3- b ]quinoxaline were synthesized. The theory calculation shows the S 1 and T 1 of both compounds own a charge-transfer feature while their T 2 states have a local excitation feature. The calculated k RISC(T2-S1) is one to 2 orders of magnitude larger than k RISC(T1-S1) . Thus, the nonadiabatic spin-vibronic mechanism involved in the T 2 state is suggested to be responsible for the thermally activated delayed fluorescence (TADF) feature. Meanwhile, when 2-methyl-9,10-bis(naphthalen-2-yl)anthracene is selected as host, the maximum luminance of the device based on 67dMeOTPA-FQ is up to 104215 cd·m -2 , and the external quantum efficiency (EQE) keeps in the 8.2-8.0% range with the luminance changed from 55.0 cd·m -2 to 90000 cd·m -2 , only 2.4% efficiency roll-off. As for 58dMeOTPA-FQ , a slightly lower EQE of 7.1-6.7% with the luminance range of 1-40000 cd·m -2 was achieved for orange-red emission. Both the reverse intersystem crossing (RISC) and triplet-triplet annihilation mechanisms are supposed to concurrently contribute to the utilization of triplet excitons and suppress the notorious efficiency roll-off observed in TADF-based devices.

Can a robotic gripper only operate when attached to a robotic arm? The application space of the traditional gripper is limited by the robotic arm. Giving robot grippers the ability to move will expand their range of applications. Inspired by rich behavioral repertoire observed in octopus, we implement an integrated multifunctional soft robotic gripper with 6 independently controlled Arms. It can execute 8 different gripping actions for different objects, such as irregular rigid/soft objects, elongated objects with arbitrary orientation, and plane/curved objects with larger sizes than the grippers. Moreover, the soft gripper can realize omnidirectional crawling and swimming by itself. The soft gripper can perform highly integrated tasks of releasing, crawling, swimming, grasping, and retrieving objects in a confined underwater environment. Experimental results demonstrate that the integrated capabilities of multimodal adaptive grasping and omnidirectional motions enable dexterous manipulations that traditional robotic arms cannot achieve. The soft gripper may apply to highly integrated and labor-intensive tasks in unstructured underwater environments, including ocean litter collecting, capture fishery, and archeological exploration., Competing Interests: Competing interests: The authors declare that they have no competing interests., (Copyright © 2024 Mingxin Wu et al.)

Background: In this study, we aimed to construct a robust diagnostic model that can predict the early onset of heart failure in patients with ST-elevation myocardial infarction (STEMI) following a primary percutaneous coronary intervention (PCI). This diagnostic model can facilitate the early stratification of high-risk patients, thereby optimizing therapeutic management., Methods: We performed a retrospective analysis of 664 patients with STEMI who underwent their inaugural PCI. We performed logistic regression along with optimal subset regression and identified important risk factors associated with the early onset of heart failure during the time of admission. Based on these determinants, we constructed a predictive model and confirmed its diagnostic precision using a receiver operating characteristic (ROC) curve., Results: The logistic and optimal subset regression analyses revealed the following three salient risk factors crucial for the early onset of heart failure: the Killip classification, the presence of renal insufficiency, and increased troponin T levels. The constructed prognostic model exhibited excellent discriminative ability, which was indicated by an area under the curve value of 0.847. The model's 95% confidence interval following 200 Bootstrap iterations was found to be between 0.767 and 0.925. The Hosmer-Lemeshow test revealed a chi-square value of 3.553 and a p -value of 0.938. Notably, the calibration of the model remained stable even after 500 Bootstrap evaluations. Furthermore, decision curve analysis revealed a substantial net benefit of the model., Conclusion: We have successfully constructed a diagnostic prediction model to predict the incipient stages of heart failure in patients with STEMI following primary PCI. This diagnostic model can revolutionize patient care, allowing clinicians to quickly identify and create individualized interventions for patients at a higher risk., Competing Interests: None., (AJCD Copyright © 2024.)

The top-down approach in designing and fabricating origami robots could achieve far more complicated functions with compliant and elegant designs than traditional robots. This study presents the design, fabrication, and testing of a reticular origami soft robotic gripper that could adapt to the shape of the grasping subject and grasp the subject within 80 ms from the trigger instance. A sensing mechanism consisting of the resistive pressure sensor array and flexible elongation sensor is designed to validate further the shape-adaptive grasping capability and model the rough shape and size of the subject. The grasping test on various objects with different shapes, surface textures, sizes, and living animals further validates the excellent grasping capabilities of the gripper. The gripper could be either actively triggered by actuation or passively triggered by a minimum of 0.0014 J disturbance energy. Such features make it particularly suitable for applications such as capturing underwater creatures and illegal drone control.

Cerebral ischaemia‒reperfusion injury (IRI), during which neurons undergo oxygen-glucose deprivation/reoxygenation (OGD/R), is a notable pathological process in many neurological diseases. N1-methyladenosine (m 1 A) is an RNA modification that can affect gene expression and RNA stability. The m 1 A landscape and potential functions of m 1 A modification in neurons remain poorly understood. We explored RNA (mRNA, lncRNA, and circRNA) m 1 A modification in normal and OGD/R-treated mouse neurons and the effect of m 1 A on diverse RNAs. We investigated the m 1 A landscape in primary neurons, identified m 1 A-modified RNAs, and found that OGD/R increased the number of m 1 A RNAs. m 1 A modification might also affect the regulatory mechanisms of noncoding RNAs, e.g., lncRNA-RNA binding proteins (RBPs) interactions and circRNA translation. We showed that m 1 A modification mediates the circRNA/lncRNA‒miRNA-mRNA competing endogenous RNA (ceRNA) mechanism and that 3' untranslated region (3'UTR) modification of mRNAs can hinder miRNA-mRNA binding. Three modification patterns were identified, and genes with different patterns had intrinsic mechanisms with potential m 1 A-regulatory specificity. Systematic analysis of the m 1 A landscape in normal and OGD/R neurons lays a critical foundation for understanding RNA modification and provides new perspectives and a theoretical basis for treating and developing drugs for OGD/R pathology-related diseases., Competing Interests: CZ, XY, MH, QL, XL, LL, EQ, MW, LQ, HJ, ZQ, YL, XK, MB, SF, HZ No competing interests declared, (© 2023, Zhang, Yi, Hou et al.)

Objective: To explore the effect of H 2 O 2 -actived RAW264.7 macrophages on the migration, proliferation, and osteogenesis gene expression of MC3T3-E1 in mice., Methods: MC3T3-E1 cells and RAW264.7 cells were cultured to the 7th generation. RAW264.7 macrophages were stimulated with 0, 25, 50 and 100 μmol/L H 2 O 2 , the cell proliferation rate was detected by MTS at 1, 3, and 6 hours after stimulated, and superoxide dismutase (SOD) content by SOD assay kit at 1 hour after stimulated. The appropriate concentration and action time of H 2 O 2 -actived RAW264.7 were obtained. The supernatant of RAW264.7 macrophages stimulated by H 2 O 2 or not was collected at 24 hours. Then, the supernatant was used to culture MC3T3-E1 cells in groups B (not stimulated by H 2 O 2 ) and C (stimulated by H 2 O 2 ), and DMEM was used as a control in group A. The migration of MC3T3-E1 cells was detected at 12 and 24 hours by cell scratch test, the proliferation of MC3T3-E1 cells at 24, 48, and 72 hours by MTS assay. MC3T3-E1 cells were cultured with only complete medium in blank control group, with complete medium containing 50 μg/mL vitamin C + 10 nmol/L β sodium glycerophosphate in positive group, normal control group (adding the supernatant not stimulated by H 2 O 2 ), and experimental group (adding the supernatant stimulated by H 2 O 2 ). At 3, 7, and 14 days, RT-PCR was used to determine the osteogenesis related mRNA expressions of alkaline phosphatase (ALP), Runx2, osteopontin (OPN), osteocalcin (OC), bone sialoprotein (BSP), and collagen type I (COL-I)., Results: The results of MTS and SOD assay showed that the appropriate concentration and action time of H 2 O 2 -actived RAW264.7 macrophages were 25 μmol/L and 1 hour, respectively. MTS assay showed that the proliferation rate of MC3T3-E1 cells was significant higher in groups B and C than group A ( P <0.05), in group B than group C, and significant difference was shown between groups at 2 and 3 days ( P <0.05). The cell scratch test indicated that the migration of MC3T3-E1 cells was significantly faster in groups B and C than group A, and in group C than group B at 12 hours ( P <0.05); many migrated cells were observed in all scratch sites of groups B and C at 24 hours. When compared with positive control group, the mRNA expressions of ALP, Runx2, OC and BSP in experimental group were significantly down-regulated at 7 and 14 days ( P <0.05). When compared blank control group, the mRNA expressions of OPN and COL-I in experimental group were significantly down-regulated at 7 and 14 days ( P <0.05)., Conclusions: The appropriate concentration and action time of H 2 O 2 -actived RAW264.7 macrophages are 25 μmol/L and 1 hour. The H 2 O 2 -actived RAW264.7 cells can promote MC3T3-E1 cells migration, and suppress MC3T3-E1 cells proliferation and expressions of osteogenesis related genes.