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Mid‐infrared (MIR) lasers generated by nonlinear optical (NLO) crystals have aroused extensive attention in various military and civilian applications. Among the MIR NLO crystal family, LiInSe2 (LISe) is a promising candidate in the generation of MIR lasers due to its wide transmission range, large bandgap, and high laser‐induced damage threshold. However, the intrinsic defects in LISe induce optical losses, which will induce laser damage and hinder the performance of MIR laser generation. In this work, the mechanism of optical absorption induced by defects is revealed in LISe through transient absorption (TA) spectroscopy. It is verified that the deep‐level defects in LISe give rise to the extra optical absorption, which is owing to the excited state absorption (ESA) and photo‐induced absorption (PIA). Accordingly, for improving the optical properties of LISe crystals, Li2Se vapor‐mediated annealing to reduce defects concentration is rationally designed. The results confirmed that the optical properties of annealed LISe are improved due to the decrease of defects concentration. Ultimately, the performance of MIR laser generation is successfully enhanced by using the annealed LISe crystal. This work provides deep insights into the defect‐induced absorption losses in LISe crystals and promotes the application of LISe crystals in MIR laser generation. [ABSTRACT FROM AUTHOR]

Accurate target prediction, especially bounding box estimation, is a key problem in visual tracking. Many recently proposed trackers adopt the refinement module called IoU predictor by designing a high‐level modulation vector to achieve bounding box estimation. However, due to the lack of spatial information that is important for precise box estimation, this simple one‐dimensional modulation vector has limited refinement representation capability. In this study, a novel IoU predictor (IoUNet++) is designed to achieve more accurate bounding box estimation by investigating spatial matching with a spatial cross‐layer interaction model. Rather than using a one‐dimensional modulation vector to generate representations of the candidate bounding box for overlap prediction, this paper first extracts and fuses multi‐level features of the target to generate template kernel with spatial description capability. Then, when aggregating the features of the template and the search region, the depthwise separable convolution correlation is adopted to preserve the spatial matching between the target feature and candidate feature, which makes their IoUNet++ network have better template representation and better fusion than the original network. The proposed IoUNet++ method with a plug‐and‐play style is applied to a series of strengthened trackers including DiMP++, SuperDiMP++ and SuperDIMP_AR++, which achieve consistent performance gain. Finally, experiments conducted on six popular tracking benchmarks show that their trackers outperformed the state‐of‐the‐art trackers with significantly fewer training epochs. [ABSTRACT FROM AUTHOR]

Blood oxygenation level‐dependent (BOLD) signals in the white matter (WM) have been demonstrated to encode neural activities by showing structure‐specific temporal correlations during resting‐state and task‐specific imaging of fiber pathways with various degrees of correlations in strength and time delay. Previous neuroimaging studies have shown state‐dependent functional connectivity and regional amplitude of signal fluctuations in brain gray matter across wakefulness and nonrapid eye movement (NREM) sleep cycles. However, the functional characteristics of WM during sleep remain unknown. Using simultaneous electroencephalography and functional magnetic resonance imaging data during wakefulness and NREM sleep collected from 66 healthy participants, we constructed 10 stable WM functional networks using clustering analysis. Functional connectivity between these WM functional networks and regional amplitude of WM signal fluctuations across multiple low‐frequency bands were evaluated. In general, decreased WM functional connectivity between superficial and middle layer WM functional networks was observed from wakefulness to sleep. In addition, functional connectivity between the deep and cerebellar networks was higher during light sleep and lower during both wakefulness and deep sleep. The regional fluctuation amplitude was always higher during light sleep and lower during deep sleep. Importantly, slow‐wave activity during deep sleep negatively correlated with functional connectivity between WM functional networks but positively correlated with fluctuation strength in the WM. These observations provide direct physiological evidence that neural activities in the WM are modulated by the sleep–wake cycle. This study provided the initial mapping of functional changes in WM during sleep. [ABSTRACT FROM AUTHOR]

To electrically control magnetic properties of material is promising toward spintronic applications, where the investigation of carrier doping effects on antiferromagnetic (AFM) materials remains challenging due to their zero net magnetization. In this work, the authors find electron doping dependent variation of magnetic orders of a 2D AFM insulator NiPS3, where doping concentration is tuned by intercalating various organic cations into the van der Waals gaps of NiPS3 without introduction of defects and impurity phases. The doped NiPS3 shows an AFM‐ferrimagnetic (FIM) transition at a doping level of 0.2–0.5 electrons/cell and a FIM‐AFM transition at a doping level of ≥0.6 electrons/cell. The authors propose that the found phenomenon is due to competition between Stoner exchange dominated inter‐chain ferromagnetic order and super‐exchange dominated AFM order at different doping level. The studies provide a viable way to exploit correlation between electronic structures and magnetic properties of 2D magnetic materials for realization of magnetoelectric effect. [ABSTRACT FROM AUTHOR]

Terahertz (THz) technology has attracted great attention in the past few decades for its unique applications in various fields, including spectroscopy, noninvasive detection, wireless communications, and imaging. In parallel to this, the practical, fast, and broadband modulation of THz waves is becoming indispensable. Two‐dimensional (2D) materials exhibit unusual optical and electrical properties, which has prompted tremendous interest and significant advances in THz modulation. This review provides the recent progress in 2D materials‐based THz modulators, outlining the operating principles, including all‐optical, electro‐optic, magneto‐optic, and other exotic mechanisms. We focus on the recent advances in THz modulation by the designed photonic structures, such as heterostructure, metamaterial, capacitor, optical cavity, and waveguide integration. Lastly, we discussed the challenges and opportunities for 2D materials‐based THz modulators and presented our prospects for the future development. [ABSTRACT FROM AUTHOR]

The LD conversion offers great potential in providing an additional degree of freedom that may be beneficial to novel polarization‐wavelength‐selective detectors and optical switching. However, conventional crystals with optical anisotropy typically show unidirectional LD over a broad wavelength range and the materials with LD conversion behavior remain scarce. Here, by combining angle‐resolved polarized optical absorption measurements and theoretical calculations, this study demonstrates that quasi‐1D Weyl semimetal (TaSe4)2I single crystal shows unique LD conversion phenomenon at the wavelength of 1064 nm. Meanwhile, (TaSe4)2I persists giant linear optical anisotropy due to the intrinsic feature of 1D [TaSe4] chains along the c‐axis. Additionally, the (TaSe4)2I nanoribbon exhibits anisotropic second harmonic generation (SHG). These results hold significant importance to facilitate the development of topological photonics and novel photonic devices applications based on topological semimetals. [ABSTRACT FROM AUTHOR]

Oplopanax horridus, widely distributed in North America, is an herbal medicine traditionally used by Pacific indigenous peoples for various medical conditions. After oral ingestion, constituents in O. horridus extract (OhE) could be converted to their metabolites by the enteric microbiome before absorption. In this study, in order to mimic gut environment, the OhE was biotransformed using the enteric microbiome of healthy human subjects. For accurate and reliable data collection with optimized approaches in sample preparation and analytical conditions, ultra‐performance liquid chromatography and quadrupole time‐of‐flight mass spectrometry were used to characterize parent constituents and their metabolites. In the extract, 20 parent compounds were identified including polyynes, sesquiterpenes, monoterpeondids, phenylpropanoids and phenolic acids. After the biotransformation, a total of 78 metabolites were identified, of which 37 belonged to polyynes metabolites. The common biotransformation pathways are hydroxylation, acetylization, methylation and demethylation. Based on the pathway distributions, the metabolism signature of OhE has been explored. The metabolism pathways of OhE compounds are dependent on their structural classifications and hydrophilic/hydrophobic properties. In summary, with comprehensive analysis, we systematically investigated human microbiome‐derived OhE metabolites. The enteric microbial metabolism signature provides novel information for future effective use of O. horridus. [ABSTRACT FROM AUTHOR]

Despite the impressive progresses in terahertz (THz) sources and detection, there is still a big challenge for high performance active optoelectronic THz devices such as THz modulators. All‐optically controlled THz modulators with large modulation depth (MD) and wide modulation bandwidth are of great importance for the THz technology. Herein, a MoTe2/Si van der Waals (vdWs) heterostructure is rationally designed as all‐optical THz modulator by taking advantage of their similar band alignment and easy integration with Si complementary metal‐oxide‐semiconductor (CMOS). The MoTe2/Si modulator presents an ultrasensitive THz modulation performance with a MD of 99.9% under a low illumination power of 300 mW at 1064 nm. This is a record MD for TMDCs‐based all‐optically controlled THz modulators to date. Moreover, the MoTe2/Si modulator exhibits broadband modulation performance with a wide frequency range from 0.3 to 2.0 THz. The high modulation performance under low illumination power is beneficial for practical application with low energy consumption and easy heat dissipation, which is advantageous to modulator chip. This work validates a facile protocol for fabricating high performance THz modulators and paves the way for their practical applications in THz technology. [ABSTRACT FROM AUTHOR]

Background & Aims: Nonalcoholic fatty liver disease encompasses isolated steatosis or nonalcoholic fatty liver and nonalcoholic steatohepatitis (NASH). NASH develops from isolated steatosis with obscure driving forces. We aim to identify key factors promoting this transition. Methods: Following 21‐week of high‐fat diet feeding, obese mice were classified into two groups termed as isolated steatosis and NASH based on hematoxylin‐eosin staining of liver histology. The integrated multi‐omics analysis of lipidome, transcriptome and gut microbiome were performed in mice with isolated steatosis and NASH, and confirmed in human samples. Results: Livers in mice with NASH lost most lipids, and the transcriptional landscape was also changed dramatically in mice with NASH in relative to mice with isolated steatosis. Plasma lipidome analysis demonstrated a very clear difference between these two groups of mice, which was partially recapitulated in serum of patients with isolated steatosis and NASH. The microbiota composition revealed that Bacteroides genus and Bacteroides uniformis species decreased while Mucispirillum genus and Mucispirillum schaedleri species increased largely in mice with NASH. More importantly, we found that Bacteroides uniformis correlated positively with triglycerides (TGs) and negatively with free fatty acids (FFAs) and PE(18:1/20:4), while Mucispirillum schaedleri correlated positively with FFAs, LysoPC(20:3), LysoPC(20:4) and DG(16:1/18:2). Mechanically, administration of Bacteroides uniformis increased specific TGs, and decreased hepatic injury and inflammation in diet‐induced mice. Conclusions: Overall, through multi‐omics integration, we identified a microbiota‐lipid axis promoting the initiation of NASH from isolated steatosis, which might provide a novel perspective on NASH pathogenesis and treatment. [ABSTRACT FROM AUTHOR]

Different grades of natural manganese ores were used to remove SO2 by dry flue gas desulfurization. The grades of the manganese ores were negatively correlated with the desulfurization performance. The produced MnSO4 enriched on the surface would block the gas diffusion channels during desulfurization. The better desulfurization properties of the low‐grade manganese ores are ascribed to the highly active γ‐MnO2, the porous structure, and the high specific surface area as well as the SiO2 bridge‐like effects. This study supports the cooperative use of sulfur‐containing flue gases and low‐grade natural manganese oxides. [ABSTRACT FROM AUTHOR]

The dissolution of transition metals is the main reason for the capacity fading and structural degradation of Ni‐rich cathode materials. In this work, NiF2 is used as functional electrolyte additive for the first time to improve the performance of LiNi0.6Co0.2Mn0.2O2 cathodes by the chemical‐equilibrium principle. The suppression of transition‐metal dissolution, especially Ni, is proved by energy disperse spectroscopy and inductively coupled plasma analyses. The NiF2 additive can stabilize the cathode structure by relieving the dissolution of transition metals, which is confirmed by morphology and structure analyses. Moreover, the NiF2 additive also reduces side reactions of the cell, which is verified by self‐discharge tests and coulombic efficiency analysis. As a result, the addition of 100 ppm NiF2 elevates the capacity retention of the Li/NCM622 half‐cell from 69.53 to 79.67 % after 100 cycles, and the 100 ppm NiF2‐containing cathode delivers an initial capacity of 174.0 mAh g−1 even at 8 C after 50 cycles. [ABSTRACT FROM AUTHOR]

The activation of the heart inward rectifier potassium channel (IK1) can reduce the injury of myocardial cells by shortening the action potential duration and reducing intracellular calcium overload. Zacopride is a selective IK1 agonist and suppresses triggered arrhythmias in rat hearts. This investigation studied the effects of St. Thomas (ST) cardioplegia enriched with Zacopride on the isolated rat heart model. Sprague-Dawley rat hearts were harvested and perfused for 20 minutes with 37°C Krebs-Henseleit (KH) buffer followed by 15 minute perfusion with 4°C calcium-free KH buffer in the Control group (Con, n = 8), ST cardioplegia in the ST group (ST, n = 8) and ST cardioplegia with Zacopride in the STZ group (STZ, n = 8). After 45 minutes of arresting, all hearts were reperfused with 37°C KH buffer for 60 minutes. Hearts in the STZ group arrested faster than the Con and ST groups (9.25 ± 2.38 s vs. 72.25 ± 8.1 s, 12.75 ± 2.87 s). The recovery of the left ventricular developed pressure, ± dP/dtmax, heart rate, and coronary flow in the STZ group is significantly better than the other two groups during reperfusion. Compared with the Con and ST groups, the STZ group showed significant decreases in the maximum carciac troponin I level ( P < 0.05) and the infarct size ( P < 0.05). The superoxide dismutase level in the STZ group increased during the first 20 minutes of reperfusion ( P < 0.05). ST cardioplegia enriched with Zacopride has beneficial effects against ischemia-reperfusion injury in this isolated rat heart model. [ABSTRACT FROM AUTHOR]

The aim of this study is to compare cerebral protection using antegrade cerebral perfusion (ACP) with various flow rates during deep hypothermic circulatory arrest (DHCA) in a piglet model. Twenty-three piglets were randomized to five groups: the control group ( n = 3), DHCA group ( n = 5), ACP25 group ( n = 5), ACP50 group ( n = 5), and ACP80 group ( n = 5). Three control piglets did not undergo operations. Twenty piglets underwent cardiopulmonary bypass (CPB) and DHCA for 60 min at 20°C. ACP was conducted at 0, 25, 50, and 80 mL/kg/min in the DHCA, ACP25, ACP50, and ACP80 group, respectively. Serum S-100B protein and neuron-specific enolase were monitored, and brain tissues were assayed for the activities of caspase-3 and stained for the evidence of apoptotic cellular injury. Rise in serum S-100B level (post-CPB-pre-CPB) in the ACP50 group was significantly lower than that in the ACP80 group ( P = 0.001). Caspase-3 levels were significantly elevated in the ACP80 group compared with the ACP25 ( P = 0.041) and ACP50 group ( P = 0.01), while positive terminal deoxyneucleotidyl transferase-mediated biotin-dUTP nick end labeling reaction scores in the ACP80 group were significantly higher than those in the ACP25 ( P = 0.043) and ACP50 group ( P = 0.023). Cerebral protection effects of ACP at 25 and 50 mL/kg/min were superior to that of ACP at 80 mL/kg/min as determined by cerebral markers, immunology, and histology. [ABSTRACT FROM AUTHOR]

THz modulators based on 2D materials are attracting attention due to their potential applications in THz communication, sensing, and biomedical diagnostics. The authors present recent progress on 2D materials with different photonic structures, fundamental of THz modulation, and THz operation principles. This work provides useful guidance for the design strategy of 2D materials based THz modulators. (DOI: 10.1002/inf2.12236) [ABSTRACT FROM AUTHOR]

isolation and structure elucidation of two new pregnane glycosides, cynatraosides A (I) and B (II), along with six known steroids [ABSTRACT FROM AUTHOR]