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"Bu, Qing"
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A Timing View of the Additional High-energy Spectral Component Discovered in the Black Hole Candidate Swift J1727.8-1613
We present an energy-dependent analysis for the type-C quasiperiodic oscillations (QPOs) observed in the black hole X-ray binary Swift J1727.8–1613 using Insight-HXMT observations. We find that the QPO fractional rms at energies above 40 keV is significantly higher than that below 20 keV. This is the first report of a high energy (HE) rms excess in the rms spectrum of a black hole X-ray binary. In the high energy band, an extra hard component is observed in addition to the standard thermal Comptonization component at a similar energy band. The value of the QPO HE rms excess is not only correlated with the disk parameters and the photon index of the standard Comptonization component but also exhibits a moderate positive correlation with the flux of the additional hard spectral component. No features in the QPO phase-lag spectra are seen corresponding to the additional hard component. We propose that the additional hard component in the spectrum may originate from jet emission and the associated QPO HE rms excess can be explained by the precession of the jet base.
Journal Article
Arthroscopic Anatomical Repair of Anterior Talofibular Ligament for Chronic Lateral Instability of the Ankle: Medium‐ and Long‐Term Functional Follow‐Up
Objective To evaluate the functional outcomes of arthroscopic anatomical repair of anterior talofibular ligament (ATFL) in the treatment of chronic lateral ankle instability (CLAI) during medium‐ and long‐term follow‐up. Methods From September 2014 to August 2017, the data of 37 patients (23 males, 14 females; 12 left ankles, 25 right ankles) aged between 21 and 56 years, with an average age of 32.17 ± 6.35 years, presenting with CLAI, was retrospectively analyzed. Among them, 32 injuries were caused by sprain and five injuries were caused by car accidents. The course of the disease lasted for 12 to 60 months, with an average of 26.07 ± 13.29 months. All patients had intact skin around the ankle and no skin lesions. All patients underwent arthroscopic anatomical repair of ATFL, with the fixation of one to two anchors. Pre‐ and post‐operative visual analogue scales (VAS), the American Orthopaedic Foot and Ankle Society Ankle‐Hindfoot Score (AOFAS), and the Karlsson Ankle Functional Score (KAFS) were compared to evaluate the curative effect of the operation. Results The operation was successful in all 37 cases. The operation time ranged from 40 to 75 min, with an average of 51.25 ± 11.49 min. After surgery, all incisions healed in stage I and there were no complications such as nerve, blood vessel and tendon injury, implant rejection, or suture rejection. Hospital stays of postoperative patients were 3 to 5 days, with an average of 3.77 ± 1.36 days. All patients were followed for 24 to 45 months, averaging 33.16 ± 10.58 months. For three patients with CLAI combined with mild limitation of subjective ankle movement, joint activity was normal after rehabilitation function exercise and proprioceptive function training for 2 months. At the final follow‐up, ankle pain had disappeared completely. The ankle varus stress test and ankle anterior drawer test were both negative. Range of joint motion was good. There was no lateral instability of the ankle and all patients returned to normal gait. The mean VAS score decreased to 1.12 ± 0.13, the AOFAS score increased to 92.53 ± 4.87, and the KAFS score increased to 93.36 ± 6.15. All the follow‐up indexes were significantly different from those before surgery. Conclusion Arthroscopic anatomical repair of ATFL for CLAI is precise, with less surgical trauma and reliable medium‐ and long‐term effect.
Journal Article
Hilbert–Huang Transform Analysis of Quasiperiodic Oscillations in MAXI J1820+070
We present a time-frequency analysis, based on the Hilbert–Huang transform, of the evolution of the low-frequency quasiperiodic oscillations observed in the black hole X-ray binary MAXI J1820+070. Through the empirical mode decomposition method, we decompose the light curve of the quasiperiodic oscillation (QPO) component and measure its intrinsic phase lag between photons from different energy bands. We find that the QPO phase lag is negative (low-energy photons lag behind high-energy photons); meanwhile, the absolute value of the lag increases with energy. By applying the Hilbert transform to the light curve of the QPO, we further extract the instantaneous frequency and amplitude of the QPO. Comparing these results with those from the Fourier analysis, we find that the broadening of the QPO peak is mainly caused by frequency modulation. Through further analysis, we find that these modulations could share a common physical origin with the broadband noise, and can be well explained by the internal shock model of the jet.
Journal Article
Ginsenoside Rb1, Compound K and 20(S)-Protopanaxadiol Attenuate High-Fat Diet-Induced Hyperlipidemia in Rats via Modulation of Gut Microbiota and Bile Acid Metabolism
Hyperlipidemia, characterized by elevated serum lipid concentrations resulting from lipid metabolism dysfunction, represents a prevalent global health concern. Ginsenoside Rb1, compound K (CK), and 20(S)-protopanaxadiol (PPD), bioactive constituents derived from Panax ginseng, have shown promise in mitigating lipid metabolism disorders. However, the comparative efficacy and underlying mechanisms of these compounds in hyperlipidemia prevention remain inadequately explored. This study investigates the impact of ginsenoside Rb1, CK, and PPD supplementation on hyperlipidemia in rats induced by a high-fat diet. Our findings demonstrate that ginsenoside Rb1 significantly decreased body weight and body weight gain, ameliorated hepatic steatosis, and improved dyslipidemia in HFD-fed rats, outperforming CK and PPD. Moreover, ginsenoside Rb1, CK, and PPD distinctly modified gut microbiota composition and function. Ginsenoside Rb1 increased the relative abundance of Blautia and Eubacterium, while PPD elevated Akkermansia levels. Both CK and PPD increased Prevotella and Bacteroides, whereas Clostridium-sensu-stricto and Lactobacillus were reduced following treatment with all three compounds. Notably, only ginsenoside Rb1 enhanced lipid metabolism by modulating the PPARγ/ACC/FAS signaling pathway and promoting fatty acid β-oxidation. Additionally, all three ginsenosides markedly improved bile acid enterohepatic circulation via the FXR/CYP7A1 pathway, reducing hepatic and serum total bile acids and modulating bile acid pool composition by decreasing primary/unconjugated bile acids (CA, CDCA, and β-MCA) and increasing conjugated bile acids (TCDCA, GCDCA, GDCA, and TUDCA), correlated with gut microbiota changes. In conclusion, our results suggest that ginsenoside Rb1, CK, and PPD supplementation offer promising prebiotic interventions for managing HFD-induced hyperlipidemia in rats, with ginsenoside Rb1 demonstrating superior efficacy.
Journal Article
Rational construction of genome-reduced and high-efficient industrial Streptomyces chassis based on multiple comparative genomic approaches
Background
Streptomyces chattanoogensis
L10 is the industrial producer of natamycin and has been proved a highly efficient host for diverse natural products. It has an enormous potential to be developed as a versatile cell factory for production of heterologous secondary metabolites. Here we developed a genome-reduced industrial
Streptomyces chassis
by rational ‘design-build-test’ pipeline.
Results
To identify candidate large non-essential genomic regions accurately and design large deletion rationally, we performed genome analyses of
S. chattanoogensis
L10 by multiple computational approaches, optimized Cre/
loxP
recombination system for high-efficient large deletion and constructed a series of universal suicide plasmids for rapid
loxP
or
loxP
mutant sites inserting into genome. Subsequently, two genome-streamlined mutants, designated
S. chattanoogensis
L320 and L321, were rationally constructed by depletion of 1.3 Mb and 0.7 Mb non-essential genomic regions, respectively. Furthermore, several biological performances like growth cycle, secondary metabolite profile, hyphae morphological engineering, intracellular energy (ATP) and reducing power (NADPH/NADP
+
) levels, transformation efficiency, genetic stability, productivity of heterologous proteins and secondary metabolite were systematically evaluated. Finally, our results revealed that L321 could serve as an efficient
chassis
for the production of polyketides.
Conclusions
Here we developed the combined strategy of multiple computational approaches and site-specific recombination system to rationally construct genome-reduced
Streptomyces
hosts with high efficiency. Moreover, a genome-reduced industrial
Streptomyces chassis
S. chattanoogensis
L321 was rationally constructed by the strategy, and the
chassis
exhibited several emergent and excellent performances for heterologous expression of secondary metabolite. The strategy could be widely applied in other
Streptomyces
to generate miscellaneous and versatile
chassis
with minimized genome. These
chassis
can not only serve as cell factories for high-efficient production of valuable polyketides, but also will provide great support for the upgrade of microbial pharmaceutical industry and drug discovery.
Journal Article
Quantum Neural Network with Improved Quantum Learning Algorithm
We present a quantum BP neural network with the universality of single-qubit rotation gate and two-qubit Controlled-NOT gate. Also, we show the process of the BP learning algorithm for the quantum model, and propose an improved BP learning algorithm based on quantum genetic algorithm. The type recognition simulation of the Matlab program shows the efficiencies of the quantum neural network and the improved learning algorithm.
Journal Article
Alanine Substitution to Determine the Effect of LR5 and YR6 Rice Peptide Structure on Antioxidant and Anti-Inflammatory Activity
The relationship between the structure of peptides LR5 (LHKFR) and YR6 (YGLYPR) and their antioxidant and anti-inflammatory activity remains unclear. Herein, leucine, tyrosine, proline, and phenylalanine at different positions in the peptides were replaced by Alanine (Ala), and two new pentapeptides (AR5 and LAR5) and four hexapeptides (AGR6, YAR6, YLR6, and YGR6) were obtained. The effect of Ala replacement on the hydrophobicity, cytotoxicity, NO inhibition rate, and active oxygen radical scavenging ability of these peptides and their antioxidant and anti-inflammatory abilities were investigated. The results indicated that the hydrophobicity of the peptides was associated with their amino acid composition and their specific sequence. However, hydrophobicity had no significant effect on cytotoxicity. Ala replacement was shown to enhance hydrophobicity and consequently increased the antioxidant and anti-inflammatory activity of the peptides. The molecular docking studies indicated that the amino acid interactions of the peptide with the Keap1 protein influenced the hydrophobicity and thus affected the antioxidant activity of the peptide.
Journal Article
A Novel Neural Network Based on Quantum Computing
Since the first quantum neural network based on quantum computing was proposed by famous scholar Kak, much attention has been taken focus on designing new quantum neural network models. In this paper, a novel efficient quantum feed-forward neural network based on quantum computing is established, which adopts genetic algorithm to improve the traditional back propagation algorithm in parameters learning process. We clearly show the mathematical process of the new proposed quantum network model and improved algorithm. The experimental results of MATLAB simulations show that the new network model which makes the best use of fast quantum neural computation does a better job in function approximation and prediction of educational short video’s spreading capacity than traditional back propagation neural network, and the improved algorithm is more efficient than common back propagation algorithm in the proposed quantum network model. Our model can be widely used in weather prediction, handwriting recognition, speech recognition, and other aspects.
Journal Article
Separating the Role of Mixing‐Entropy on the Dynamics of Glass‐Forming Liquids
While the concept of high entropy has gained prominence in materials design, disentangling specific impacts of entropy on material properties from the enthalpy of mixing remains elusive. It is demonstrated that the role of entropy can be distinguished from the dynamics of glass‐forming liquids through micro‐alloying. Based on experiment analysis of 79 compositions, liquid fragility is found to consistently decreases under two conditions: i) when the alloying content x is minimal, irrespective of the elements used; or ii) when increasing the diversity of alloying elements at a constant x, namely the high‐entropy micro‐alloying. These observations are consistent with thermodynamic principles that favor an entropy‐dominated regime over enthalpy. These findings elucidate the subtle impact of mixing entropy on material properties and provide evidence of the entropy nature of glass transition. This research innovates by distinguishing entropy’s impact from enthalpy in materials through micro‐alloying. It finds liquid fragility decreases with minimal alloying content or increased element diversity. This clarifies entropy’s role and supports the entropy‐driven glass transition, guiding new material design.
Journal Article