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Exploration of spin defects in semiconductors for possible qubits encourages the development of the quantum field. Silicon carbide (SiC) is a suitable platform to carry spin defects, due to its excellent electrical, mechanical and optical properties, together with its convenience for crystallographic growth and doping processes. In this study, a negatively charged phosphorus-vacancy (PCVSi−) defect, consisting of a silicon vacancy and nearby substitution of a phosphorus atom to a carbon atom in 4H–SiC, is investigated by first-principles calculations. This defect is demonstrated to possess a high spin (S = 1) with relatively low formation energy. Computed zero-phonon line energy and zero-field splitting parameters of this defect are close to those of neutral divacancy (VCVSi0), negatively charged nitrogen-vacancy center (NCVSi−) and some other color centers, which indicate a similarity of both optical and spin properties among them. Moreover, the electron spin coherence time of this defect turns out to be 1.15–1.40 ms. Such a long coherence time provides the defect with reliability for quantum information processing. Our results show that the PCVSi− defect can be a promising candidate for a qubit. [ABSTRACT FROM AUTHOR]

Based on the framework of signed graphs, this paper investigates the finite‐time (FET) bipartite synchronization of Takagi‐Sugeno (T–S) fuzzy coupled neural networks with output coupling and state‐dependent parameters. Adaptive control schemes with quantizer are designed, and generalized norm is considered. Based on the framework of bipartite synchronization and FET synchronization, several sufficient conditions are established to realize the goal of synchronization by using Lyapunov functional method. Moreover, some numerical simulations are provided to illustrate the theoretical results. [ABSTRACT FROM AUTHOR]

In this study, three different brands of commercially available marinated tofu were analyzed and compared with homemade products to explore the effect of key flavor substances on their sensory quality, sensory properties, texture characteristics, and volatile components. The texture characteristics and flavor substances of the three brands of commercially available marinated tofu were significantly different from those of homemade products. A total of 64 volatile components were identified by headspace-gas chromatography-ion mobility spectrometry (HS-GC-IMS), mainly including 11 hydrocarbons, 11 alcohols, 10 ketones, 15 aldehydes, 4 esters, 1 acid, and 12 other volatile substances. Among these, nine key flavor compounds (ROAV > 1, VIP > 1) were identified using the relative odor activity value (ROAV) combined with a partial least squares discriminant analysis (PLS-DA) and variable importance in projection, including α-Pinene, β-Myrcene, α-Phellandrene, 1-Penten-3-one, Butanal, 3-Methyl butanal, acetic acid ethyl ester, 1,8-Cineol, and 2-Pentyl furan. The correlation heatmap showed that sensory evaluation was positively correlated with hardness, gumminess, chewiness, and springiness while negatively correlated with 2-Pentyl furan, α-Pinene, resilience, α-Phellandrene, 1-Penten-3-one, acetic acid ethyl ester, and 1,8-Cineol. Overall, this study provides a theoretical reference for developing new instant marinated tofu snacks. [ABSTRACT FROM AUTHOR]

The defects distribution of ion-implanted SiC is a key to understanding changes in the electronic, optical, and mechanical properties of SiC devices. However, accessing the defect distribution within the sample primarily relies on simulation, yet a number of factors remain unaccounted for in the simulation results, ultimately resulting in numerous inaccuracies. To address this issue, a defect distribution investigation method based on the combination of argon ion etching and deep-ultraviolet (DUV) Raman spectroscopy has been established. The defects at different depths were exposed to the surface by etching, and the crystal quality of the surface layer was assessed using Raman spectra with a 266 nm DUV laser. The spectra for the H+ implanted 4H-SiC showed that the full width at half maximum of the transverse optical mode at 781 cm−1 and the longitudinal optical mode at 965 cm−1 exhibited an increasing and then decreasing trend, approximate to a Gaussian distribution. These results were confirmed with the transmission electron microscopy cross-sectional image and SRIM-2013 simulation. The establishment of this analytical investigation method can be widely applied to other semiconductor materials, without the need for electrodes and sample contamination. [ABSTRACT FROM AUTHOR]

Cancer metastasis is the leading cause of mortality in patients with hepatocellular carcinoma (HCC). To meet the rapid malignant growth and transformation, tumor cells dramatically increase the consumption of nutrients, such as amino acids. Peptide transporter 1 (PEPT1), a key transporter for small peptides, has been found to be an effective and energy‐saving intracellular source of amino acids that are required for the growth of tumor cells. Here, the role of PEPT1 in HCC metastasis and its underlying mechanisms is explored. PEPT1 is upregulated in HCC cells and tissues, and high PEPT1 expression is associated with poor prognosis in patients with HCC. PEPT1 overexpression dramatically promoted HCC cell migration, invasion, and lung metastasis, whereas its knockdown abolished these effects both in vitro and in vivo. Mechanistic analysis revealed that high PEPT1 expression increased cellular dipeptides in HCC cells that are responsible for activating the MAP4K4/G3BP2 signaling pathway, ultimately facilitating the phosphorylation of G3BP2 at Thr227 and enhancing HCC metastasis. Taken together, these findings suggest that PEPT1 acts as an oncogene in promoting HCC metastasis through dipeptide‐induced MAP4K4/G3BP2 signaling and that the PEPT1/MAP4K4/G3BP2 axis can serve as a promising therapeutic target for metastatic HCC. [ABSTRACT FROM AUTHOR]

Autophagy may play an important role in the occurrence and development of glucocorticoid‐induced osteonecrosis of the femoral head (GC‐ONFH). Lithium is a classical autophagy regulator, and lithium can also activate osteogenic pathways, making it a highly promising therapeutic agent for GC‐ONFH. We aimed to evaluate the potential therapeutic effect of lithium on GC‐ONFH. For in vitro experiments, primary osteoblasts of rats were used for investigating the underlying mechanism of lithium's protective effect on GC‐induced autophagy levels and osteogenic activity dysfunction. For in vivo experiments, a rat model of GC‐ONFH was used for evaluating the therapeutic effect of oral lithium on GC‐ONFH and underlying mechanism. Findings demonstrated that GC over‐activated the autophagy of osteoblasts and reduced their osteogenic activity. Lithium reduced the over‐activated autophagy of GC‐treated osteoblasts through PI3K/AKT/mTOR signalling pathway and increased their osteogenic activity. Oral lithium reduced the osteonecrosis rates in a rat model of GC‐ONFH, and restrained the increased expression of autophagy related proteins in bone tissues through PI3K/AKT/mTOR signalling pathway. In conclusion, lithium can restrain over‐activated autophagy by activating PI3K/AKT/mTOR signalling pathway and up‐regulate the expression of genes for bone formation both in GC induced osteoblasts and in a rat model of GC‐ONFH. Lithium may be a promising therapeutic agent for GC‐ONFH. However, the role of autophagy in the pathogenesis of GC‐ONFH remains controversial. Studies are still needed to further explore the role of autophagy in the pathogenesis of GC‐ONFH, and the efficacy of lithium in the treatment of GC‐ONFH and its underlying mechanisms. [ABSTRACT FROM AUTHOR]

Metal–halide perovskite nanocrystals (NCs) have gained significant attention in the field of optoelectronic and photonic devices due to their promising applications. Despite their exceptional optical properties, the impact of different synthetic strategies on the fundamental nature of NCs, such as nonradiative recombination centers, remains poorly understood. In this study, we investigated the photophysical properties of CsPbBr3 NCs synthesized using two distinct methods, hot injection and ligand-assisted reprecipitation, at the individual particle level. We observed different blinking behaviors under specific photoexcitation power densities and proposed, through intensity–lifetime analysis and Monte–Carlo simulations, that these different synthetic strategies can fabricate NCs with similar crystal structures but distinct surface quenchers with varying energy levels, which significantly affected the photo-induced blinking-down and blinking-up behaviors in individual NCs. Our findings indicate a practical and feasible approach for controlling defect engineering in perovskite NCs, with significant implications for their use in optoelectronic and other technological applications. [ABSTRACT FROM AUTHOR]