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Abstract New proteasomes are produced to accommodate increases in cellular catabolic demand and prevent the accumulation of cytotoxic proteins. Formation of the proteasomal 20S core complex relies on the function of the five chaperones PAC1-4 and POMP. Here, to understand how these chaperones facilitate proteasome assembly, we tagged the endogenous chaperones using CRISPR/Cas gene editing and examined the chaperone-bound complexes by cryo-EM. We observe an early α-ring intermediate subcomplex that is stabilized by PAC1-4, which transitions to β-ring assembly upon dissociation of PAC3/PAC4 and rearrangement of the PAC1 N-terminal tail. Completion of the β-ring and dimerization of half-proteasomes repositions critical lysine K33 to trigger cleavage of the β pro-peptides, leading to the concerted dissociation of POMP and PAC1/PAC2 to yield mature 20S proteasomes. This study reveals structural insights into critical points along the assembly pathway of the human proteasome and provides a molecular blueprint for 20S biogenesis.

Objectives To assess the knowledge, attitude and practice (KAP) of patients with type A aortic dissection (AD) or their relatives regarding postoperative management.Design Cross-sectional study.Setting The participants were recruited from three hospitals between October 2022 and February 2023.Participants Patients diagnosed with type A AD or their relatives.Interventions No interventions were administered. A structured questionnaire was used to gather the demographic and KAP data from the participants.Primary and secondary outcome measures The outcome measures included the levels of KAP regarding postoperative management.Results A total of 483 participants were included. They exhibited poor knowledge (15.52±7.67, possible score: 0–32), positive attitude (31.10±5.86, possible score: 9–45) and poor practice (21.96±4.83, possible score: 8–40) towards postoperative management. The multivariable logistic analysis showed that knowledge scores (OR=1.09, 95% CI 1.05 to 1.12, p

The randomness, fluctuation and uncertainty of wind power brings great challenges to the dispatch and control of the power system. In order to raise the economy of hydro and wind power optimal dispatch, a stochastic optimal dispatching model considering the uncertainty of wind power in both time and power dimensions is proposed. The versatile distribution is used to describe the uncertainty of wind power in different power-time intervals, providing foundation for positive and negative reserves of hydro power. Moreover, to solve the multi-objective stochastic optimal dispatching model, the twin delayed deep deterministic policy gradient (TD3) algorithm is utilized, which can avoid falling into local optimum and has stronger search ability when dealing with high-dimensional multi-objective optimization problem. Simulations in a wind farm and hydro power station of western China show that the proposed model can accurately describe the uncertainty of wind power, and TD3 algorithm can find the global optimal solution more effectively than the traditional intelligent algorithms and other deep reinforcement learning algorithms.

Background Neutrophil extracellular traps (NETs) are produced by polymorphonuclear neutrophils (PMNs) stimulated by interleukin-17 (IL-17) and tumor necrosis factor α (TNF-α). However, the level and role of NETs in oral lichen planus (OLP) remain poorly understood. Objective This study aimed to investigate the expression of NETs in OLP and explore the correlation between NETs and the levels of IL-17 and TNF-α. Methods The expression and distribution of NET-related proteins in tissue samples from each group were assessed using hematoxylin-eosin (HE) staining and immunofluorescence (IF). Additionally, the expression of NET-related proteins in peripheral blood samples from each group was evaluated using cell IF technique and fluorescence spectrophotometry. The relative formation level of NETs in each group was determined by fluorescence spectrophotometry via plasma co-culture. Furthermore, the levels of inflammatory cytokines IL-17 and TNF-α in plasma and culture supernatant were measured using enzyme-linked immunosorbent assay (ELISA). Results NET-related proteins were located in the subepithelial and lamina propria layers of OLP lesions. OLP had significantly higher expression of NET-related proteins in lesion tissues and peripheral blood compared to the healthy control (HC) group (p < 0.05). The rate of NETs formation in the erosive-stage OLP (EOLP) group was significantly higher than that in the HC group (p < 0.05), in contrast, no significant increase was observed in the non-erosive OLP (NEOLP) group (p > 0.05). Furthermore, the levels of IL-17 and TNF-α in the EOLP group were significantly elevated compared to those in the NEOLP group and HC group (p < 0.05), while the levels in the NEOLP group did not significantly differ from those in the HC group (p > 0.05). The rate of NETs formation showed a positive correlation with the levels of IL-17 and TNF-α in plasma. Conclusion The expression of NET-related proteins was upregulated in OLP lesion tissues and peripheral blood. Elevated levels of IL-17 and TNF-α in peripheral blood plasma positively correlated with the rate of NETs formation, suggesting that IL-17 and TNF-α mediate the formation of NETs in OLP patients, and may thereby contribute to the development of OLP.

Abstract The performance of superconducting quantum circuits for quantum computing has advanced tremendously in recent decades; however, a comprehensive understanding of relaxation mechanisms does not yet exist. In this work, we utilize a multimode approach to characterizing energy losses in superconducting quantum circuits, with the goals of predicting device performance and improving coherence through materials, process, and circuit design optimization. Using this approach, we measure significant reductions in surface and bulk dielectric losses by employing a tantalum-based materials platform and annealed sapphire substrates. With this knowledge we predict the relaxation times of aluminum- and tantalum-based transmon qubits, and find that they are consistent with experimental results. We additionally optimize device geometry to maximize coherence within a coaxial tunnel architecture, and realize on-chip quantum memories with single-photon Ramsey times of 2.0 − 2.7 ms, limited by their energy relaxation times of 1.0 − 1.4 ms. These results demonstrate an advancement towards a more modular and compact coaxial circuit architecture for bosonic qubits with reproducibly high coherence.

Abstract In two-dimensional chiral metal-halide perovskites, chiral organic spacers endow structural and optical chirality to the metal-halide sublattice, enabling exquisite control of light, charge, and electron spin. The chiroptical properties of metal-halide perovskites have been measured by transmissive circular dichroism spectroscopy, which necessitates thin-film samples. Here, by developing a reflection-based approach, we characterize the intrinsic, circular polarization-dependent complex refractive index for a prototypical two-dimensional chiral lead-bromide perovskite and report large circular dichroism for single crystals. Comparison with ab initio theory reveals the large circular dichroism arises from the inorganic sublattice rather than the chiral ligand and is an excitonic phenomenon driven by electron-hole exchange interactions, which breaks the degeneracy of transitions between Rashba-Dresselhaus-split bands, resulting in a Cotton effect. Our study suggests that previous data for spin-coated films largely underestimate the optical chirality and provides quantitative insights into the intrinsic optical properties of chiral perovskites for chiroptical and spintronic applications.

Background: Prolonged circulatory arrest time is an independent risk factor for postoperative adverse events of type A aortic dissection (TAAD) surgery. Further reduction of the circulatory arrest time is essential to improve surgical outcomes. This study aimed to evaluate the safety and effectiveness of the novel Sutureless Integrated Stented (SIS) graft prosthesis in an animal experiment. Materials and methods: Straight type of the SIS graft prosthesis was implanted into the descending aorta of 10 adult male sheep, and the use of the device was scored on a scale of 1–10. Aortic digital subtraction angiography (DSA) was performed at 4, 14, and 26 weeks to investigate the prostheses. After 26 weeks, the animals were sacrificed for histological analysis. Results: The immediate success rate of the surgery was 100 %, and the overall mean score of the use of the device was 9.65 ± 0.99. Three animals died from non-device-related causes during follow-up. Aortic DSA showed filling defects in 5 animals. Histological analysis revealed that all prostheses were intact. Except for 2 early deaths, the other 8 prostheses were endothelialized with mild inflammation, foreign body reactions, and intimal fibrosis. The mean cross-sectional area of the sutureless region was reduced by 26.4 % (range, 1.3–39.1 %). Conclusions: The safety and effectiveness of the novel SIS graft prosthesis were acceptable, and the delivery system exhibited a promising performance. Using the SIS graft prosthesis in TAAD surgery was expected to simplify the procedures and shorten the circulatory arrest time. Further large-scale clinical trials are required to verify these findings.

Objective: To evaluate the efficacy of the fruits of the medicinal plant Forsythia suspensa (Thunb.) Vahl (FS), in treating inflammation-associated diseases through a meta-analysis of animal models, and also probe deeply into the signaling pathways underlying the progression of inflammation.Materials and methods: All data analyses were performed using Review Manager 5.3 and the results are presented as flow diagrams, risk-of-bias summaries, forest plots, and funnel plots. Summary estimates were calculated using a random- or fixed-effect model, depending on the value of I2.Results: Of the 710 records identified in the initial search, 11 were selected for the final meta-analysis. Each study extracted data from the model and treatment groups for analysis, and the results showed that FS alleviated the inflammatory cytokine levels in serum; oxidant indicator: reactive oxygen species; enzymes of liver function; endotoxin and regulatory cells in blood; and improved the antioxidant enzyme superoxide dismutase.Conclusion: FS effectively reversed the change in acute or chronic inflammation indicators in animal models, and the regulation of multiple channel proteins in inflammatory signaling pathways suggests that FS is a good potential drug for inflammatory disease drug therapy.

Rice (Oryza sativa L.), a crucial food crop that sustains over half the world’s population, is often hindered by salt stress during various growth stages, ultimately causing a decrease in yield. However, the specific mechanism of rice roots’ response to salt stress remains largely unknown. In this study, transcriptomics and lipidomics were used to analyze the changes in the lipid metabolism and gene expression profiles of rice roots in response to salt stress. The results showed that salt stress significantly inhibited rice roots’ growth and increased the roots’ MDA content. Furthermore, 1286 differentially expressed genes including 526 upregulated and 760 downregulated, were identified as responding to salt stress in rice roots. The lipidomic analysis revealed that the composition and unsaturation of membrane lipids were significantly altered. In total, 249 lipid molecules were differentially accumulated in rice roots as a response to salt stress. And most of the major phospholipids, such as phosphatidic acid (PA), phosphatidylcholine (PC), and phosphatidylserine (PS), as well as major sphingolipids including ceramide (Cer), phytoceramide (CerP), monohexose ceramide (Hex1Cer), and sphingosine (SPH), were significantly increased, while the triglyceride (TG) molecules decreased. These results suggested that rice roots mitigate salt stress by altering the fluidity and integrity of cell membranes. This study enhances our comprehension of salt stress, offering valuable insights into changes in the lipids and adaptive lipid remodeling in rice’s response to salt stress.

Ti6Al4V is the most widely used materials in aerospace, medical, nuclear power and other fields. However, due to its unique properties such as low thermal conductivity, titanium alloy poses challenges in machining processes. Electrical discharge milling (EDM) is a machining method that utilizes the electrical corrosion phenomenon of pulsed spark discharge between two electrodes to remove materials, which is highly suitable for the machining of Ti6Al4V. This paper investigates a mixed powder EDM approach for titanium alloy using a graphene solution medium known for its green and sustainable characteristics. Compared to conventional deionized water medium processing which without powder particles, the material removal rate can be increased by 50%, the surface hardness after processing was 2.5 times higher than that of the substrate, the electrode wear rate could be reduced by 40%, the surface roughness values were reduced by more than 20%. Besides that, the micro-cracks and micro-pores on the workpiece surface can be significantly reduced. Subsequently, single factor experiments and orthogonal experiments were conducted using material removal rate, electrode wear rate, and surface roughness as process indicators. The influence of processing parameters on process indicators was investigated based on optimal selection method and analysis of variance (ANOVA). Finally, the optimized parameters in graphene solution mixed powder EDM for Ti6Al4V were obtained. When using the process combination A3B3C1D2, the maximum MRR can be obtained.

The chronic accumulation of phosphogypsum (PG) has resulted in significant environmental contamination issues within the wet-process phosphoric acid (WPPA) industry. An innovative technical route for transforming PG into a resource has been achieved through the introduction of floc flotation and acid cleaning in WPPA. The floc flotation using cationic polyacrylamide as a flocculant and micro lotion, which is composed of dioctyl phthalate, polyoxyethylene(10)nonylphenyl ether, kerosene, and n-octanol as a collector, has been performed. The effect of floc flotation on product quality and the underlying mechanisms were investigated by XRF, FT-IR, SEM, and 2-dimensional fractal dimension analysis. The optimal parameters were determined through a factor experiment, which yielded the following results: floc flotation temperature 65 °C, cationic polyacrylamide 180 g/Mg, collector 1.08 kg/Mg, and flushing sulfuric acid concentration 20%. The resulting PG exhibited a high grade of 95.01%, whiteness of 70.8%, and gypsum recovery of 93.52%. Furthermore, the soluble phosphorus and soluble fluorine levels are below 0.1%. In the flotation process, the combination of polyacrylamide and collector effectively separated fine organic matter and siliceous material with a hydrophobic bubble, facilitating their upward movement and subsequent separation from PG. The new WPPA, which exhibits enhanced product quality and reduced production costs, can be utilized extensively within the WPPA. [ABSTRACT FROM AUTHOR]

Sophora flavescens, which was first recorded in Shen Nong's Herbal Classic, has the functions of clearing away heat, drying dampness, killing parasites and promoting urination. In its long-term application, traditional Chinese medicine has gradually deepened its understanding of the origin and efficacy of S. flavescens. In order to explore changes in the origin and efficacy of traditional Chinese herb S. flavescens in the history of China and Japan, in this paper, the origin and development of S. flavescens in China and Japan were compared from three aspects; the origin, medicinal efficacy, and processing methods of S. flavescens in China and Japan, hoping to provide clear understanding of the medicinal plant S. flavescens. [ABSTRACT FROM AUTHOR]