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1.
Sci Rep ; 14(1): 8335, 2024 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-38594318

RESUMO

Enhancing information security has become increasingly significant in the digital age. This paper investigates the concept of physical layer security (PLS) within a relay-aided power line communication (PLC) system operating over a multiple-input multiple-output (MIMO) channel based on MK model. Specifically, we examine the transmission of confidential signals between a source and a distant destination while accounting for the presence of multiple eavesdroppers, both colluding and non-colluding. We propose a two-phase jamming scheme that leverages a full-duplex (FD) amplify-and-forward (AF) relay to address this challenge. Our primary objective is to maximize the secrecy rate, which necessitates the optimization of the jamming precoding and transmitting precoding matrices at both the source and the relay while adhering to transmit power constraints. We present a formulation of this problem and demonstrate that it can be efficiently solved using an effective block coordinate descent (BCD) algorithm. Simulation results are conducted to validate the convergence and performance of the proposed algorithm. These findings confirm the effectiveness of our approach. Furthermore, the numerical analysis reveals that our proposed algorithm surpasses traditional schemes that lack jamming to achieve higher secrecy rates. As a result, the proposed algorithm offers the benefit of guaranteeing secure communications in a realistic channel model, even in scenarios involving colluding eavesdroppers.

2.
Phytomedicine ; 128: 155368, 2024 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-38498951

RESUMO

BACKGROUND: Idiopathic pulmonary fibrosis (IPF) is a chronic disease characterized by the abnormal proliferation of fibroblast and excessive deposition of extracellular matrix (ECM), accompanied by inflammation and ultimately respiratory failure. Yinhuang granule (YHG), with clinical properties of clearing heat, detoxifying and anti-inflammation, is commonly used to heal upper respiratory diseases in China for decades. PURPOSE: To explore the improvement of YHG on bleomycin (BLM)-induced IPF in mice and its possible engaged mechanism. METHODS: The mortality rate was recorded, lung function was determined and hematoxylin-eosin (H&E) staining was carried out to explore the alleviation of YHG on BLM-caused IPF in mice. Hydroxyproline, collagen I and collagen III contents were detected, and Sirius red and Masson staining were conducted to evaluate YHG's alleviation on lung fibrosis. The underlying mechanism was predicted by network pharmacology, and confirmed by Real-time polymerase chain reaction (RT-PCR), Western-blot (WB) and enzyme linked immunosorbent assay (ELISA). The binding affinity between related key proteins and active compounds in YHG was calculated by using molecular docking, and further validated by cellular thermal shift assay (CESTA). RESULTS: YHG (400, 800 mg/kg) weakened lung damage and pulmonary fibrosis in mice induced by BLM. Network pharmacology and experimental validation displayed that inflammation and angiogenesis participated in the YHG-provided improvement on IPF, and key involved molecules included tumor necrosis factor-α (TNFα), vascular endothelial growth factor-A (VEGFA), interleukine-6 (IL-6), etc. The data of molecular docking presented that some main active compounds from YHG had a high binding affinity with TNFR1 or VEGFR2, and some of them were further validated by CESTA. CONCLUSION: YHG effectively improved the BLM-induced IPF in mice via reducing inflammation and angiogenesis.

3.
Opt Lett ; 49(5): 1329-1332, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38427005

RESUMO

In this Letter, we demonstrate a sensitivity-enhanced strain sensor based on a shape-modulated multimode fiber (MMF). In contrast to conventional single-mode-multimode-single-mode (SMS) fiber structures, which typically contain a single cylindrical homogeneous MMF section, the shape of the MMF section in this investigation is modulated by lateral offset splicing of multiple MMF segments. Simulation results show that the designed shape-modulated MMF has a higher peak mechanical strain than that of a cylindrical MMF. Experimental results demonstrate that the strain sensitivity achieved by the shaped-modulated MMF-formed SMS fiber structure is as high as -55.63 pm/µÎµ, which is 33 times higher than that for a cylindrical MMF-formed conventional SMS fiber structure at -1.65 pm/µÎµ. This high sensitivity and low-fabrication cost SMS fiber sensor has the potential to be a promising candidate in precise strain measurement applications.

4.
Materials (Basel) ; 16(20)2023 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-37895723

RESUMO

Utilizing regenerated polyester fibers (RPFs) for the reinforcement of silty road bases not only enhances the soil's engineering performance but also offers a sustainable method for repurposing waste polyester bottles. To investigate the engineering properties and microscopic behaviors of this reinforced silty soil, a series of extensive physico-mechanical tests were conducted, supplemented by Scanning Electron Microscopy (SEM) analyses. These evaluations focused on the influence of variables such as fiber content, fiber length, moisture content, and curing duration on the modified soil's performance. The fiber content of the test was 0-1%, and the fiber length was 6-17 mm. The results indicate that curing age had a less significant impact on liquid and plastic limits than the addition of fiber, along with a marginal decline in the plasticity index over time. The rate of shrinkage in the unmodified soil was between 1.04 and 1.45 times higher than that in the fiber-reinforced soil, indicating effective shrinkage control by the fibers. However, variations in maximum dry density (ρdmax) were insignificant across different fiber contents, while a slight increase was observed in the optimum moisture content (OMC) as fiber dosage increased. After a 28-day curing period, the resilient modulus and California Bearing Ratio (CBR) met highway road base design standards. A decline in unconfined compressive strength was noted when the fiber dosage exceeded 0.2%. The addition of fibers mitigated diagonal cracking and shifted the failure pattern towards a more ductile mode. This research contributes scientific insights for the broader application and promotion of silty road base improvement techniques using RPFs.

5.
Cell Biol Toxicol ; 39(6): 3269-3285, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37816928

RESUMO

Hepatic sinusoidal obstruction syndrome (HSOS) is a death-dealing liver disease with a fatality rate of up to 67%. In the study present, we explored the efficacy of andrographolide (Andro), a diterpene lactone from Andrographis Herba, in ameliorating the monocrotaline (MCT)-induced HSOS and the underlying mechanism. The alleviation of Andro on MCT-induced rats HSOS was proved by biochemical index detection, electron microscope observation, and liver histological evaluation. Detection of hepatic ATP content, mitochondrial DNA (mtDNA) copy number, and protein expression of nuclear respiratory factor-1 (NRF1) and peroxisome proliferator-activated receptor gamma coactivator 1 alpha (PPARGC1A) demonstrated that Andro strengthened mitochondrial biogenesis in livers from MCT-treated rats. Chromatin immunoprecipitation assay exhibited that Andro enhanced the occupation of nuclear factor erythroid 2-related factor 2 (NFE2L2, also known as NRF2) in the promoter regions of both PPARGC1A and NRF1. Andro also activated the NRF2-dependent anti-oxidative response and alleviated liver oxidative injury. In Nrf2 knock-out mice, MCT induced more severe liver damage, and Andro showed no alleviation in it. Furthermore, the Andro-activated mitochondrial biogenesis and anti-oxidative response were reduced in Nrf2 knock-out mice. Contrastingly, knocking out Kelch-like ECH-associated protein 1 (Keap1), a NRF2 repressor, reduced MCT-induced liver damage. Results from co-immunoprecipitation, molecular docking analysis, biotin-Andro pull-down, cellular thermal shift assay, and surface plasmon resonance assay showed that Andro hindered the NRF2-KEAP1 interaction via directly binding to KEAP1. In conclusion, our results revealed that NRF2-dependent liver mitochondrial biogenesis and anti-oxidative response were essential for the Andro-provided alleviation of the MCT-induced HSOS. Graphical Headlights: 1. Andro alleviated MCT-induced HSOS via activating antioxidative response and promoting mitochondrial biogenesis. 2. Andro-activated antioxidative response and mitochondrial biogenesis were NRF2-dependent. 3. Andro activated NRF2 via binding to KEAP1.


Assuntos
Diterpenos , Hepatopatia Veno-Oclusiva , Camundongos , Ratos , Animais , Hepatopatia Veno-Oclusiva/induzido quimicamente , Hepatopatia Veno-Oclusiva/metabolismo , Hepatopatia Veno-Oclusiva/patologia , Antioxidantes/farmacologia , Monocrotalina/efeitos adversos , Fator 2 Relacionado a NF-E2/metabolismo , Proteína 1 Associada a ECH Semelhante a Kelch/metabolismo , Simulação de Acoplamento Molecular , Biogênese de Organelas , Diterpenos/farmacologia , Estresse Oxidativo , Camundongos Knockout , DNA Mitocondrial/metabolismo
6.
Dose Response ; 20(2): 15593258221107906, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35783237

RESUMO

Background: The personalized, heart rate-dependent computed tomography angiography (CTA) protocol can reduce the use of contrast medium (CM) and the radiation dose. This is especially beneficial for patients with CTA of coronary combined with pulmonary arteries. Purpose: To evaluate the feasibility of low CM in one-stop coronary and pulmonary arterial CTA tailored by patients' heart rate. Material and Methods: 94 patients set to undergo CTA of coronary combined with pulmonary arteries with one-stop scans. Patients were prospectively randomized into two groups: For group A (n = 47), the timing of the scans was determined according to the patient's HR using 30 mL CM; For group B (n = 47), in which the routine bolus tracking was applied by setting the ascending aortic threshold of 80 HU with 70 mL CM, scans were performed simultaneously. Results: Compared with group B, group A had slightly higher computed tomography (CT) value and image quality of pulmonary artery (CT value: group A 484.7HU; group B 457.9HU; t = 2.446, P = .016; image quality: χ2 = 8.292, P = .016), but in coronary artery wasn't statistically different between two groups(image quality: χ2 = 2.516, P = .642). Conclusion: The heart rate-dependent CM injection protocol can greatly reduce the use of CM, simplify the work-flow, and may obtain comparable or even better image quality compared with the routine bolus tracking.

7.
Phytomedicine ; 99: 153994, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35220131

RESUMO

BACKGROUND: Non-alcoholic fatty liver disease (NAFLD) is becoming more and more common in clinic in the world, and the study on its mechanism and treatment strategy has already been a research hotspot. Natural chemical compound 2,3,5,4'-tetrahydroxy-stilbene-2-O-ß-d-glucoside (TSG) is isolated from Polygonum multiflorum Thunb. that has already been reported to have the lipid-lowering activity. PURPOSE: The purpose of this research was to observe the improvement of TSG on methionine and choline deficient (MCD) diet-induced NAFLD in mice and to further elucidate its engaged mechanism. METHODS: NAFLD was induced in mice fed by MCD diet for 6 weeks. The accumulation of lipids in hepatocytes was induced by 0.5 mM non-esterified fatty acid (NEFA). Biochemical parameters in serum or livers from mice were tested. Protein and mRNA expression and stability were measured. Mitochondrial dysfunction was analyzed both in vivo and in vitro. The Label-free quantitative proteomic analysis was used to find potential involved key molecules. RESULTS: TSG attenuated hepatic parenchymal cells injury, liver inflammatory responses and hepatic fibrosis, and markedly ameliorated liver steatosis in mice from MCD group. In vitro results indicated that TSG reduced the accumulation of cellular lipids in hepatocytes induced by NEFA. TSG reduced reactive oxygen species (ROS) formation and attenuated mitochondrial dysfunction both in vivo and in vitro. The label-free quantitative proteomic analysis predicted the crucial participation of NAD-dependent protein deacylase sirtuin-5 (SIRT5). Next experimental results further evidenced that TSG enhanced SIRT5 expression in mitochondria both in vitro and in vivo. The TSG-supplied inhibition on ROS formation and mitochondrial dysfunction in hepatocytes was disappeared after the application of SIRT5 siRNA. TSG increased the expression and enzymatic activity of carnitine palmitoyltransferase 1A (CPT1A), but this enhance was diminished in hepatocytes transfected with SIRT5 siRNA. Additionally, the TSG-provided inhibition on cellular lipids accumulation was also disappeared in hepatocytes transfected with SIRT5 siRNA. Further results demonstrated that TSG increased SIRT5 expression by regulating its mRNA stability through enhancing the binding of SIRT5 mRNA with serine/arginine-rich splicing factor 2 (SRSF2), which is an RNA-binding protein (RBP). CONCLUSION: TSG attenuated liver steatosis and inhibited NAFLD progression through preventing oxidative stress injury and improving mitochondrial dysfunction, and SIRT5 played a key role in this process.

8.
Phytomedicine ; 91: 153666, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34339944

RESUMO

BACKGROUND: Metabolic-associated fatty liver disease (MAFLD) is a spectrum of liver disorders. Nonalcoholic steatohepatitis (NASH) is defined as a more serious process of MAFLD with liver inflammation. PURPOSE: This study aims to observe the alleviation of Yinhuang granule (YHG), a Chinese patent medicine, on methionine and choline-deficient diet (MCD)-induced MAFLD in mice. METHODS: Network pharmacology was used to analyze the improving effect of YHG on MAFLD and possible targets. MAFLD was induced in mice by MCD diet feeding for 6 weeks. In the last 2 weeks, the mice were orally given with YHG (400, 800 mg/kg) every day. Biochemical parameters of serum and liver, as well as hepatic gene expression were detected. RESULTS: Network pharmacology showed that YHG could improve MAFLD, inflammation, liver fibrosis, and oxidative stress. In animal experiments, YHG reduced hepatocellular damage and hepatic lipids accumulation which induced by MCD. In terms of liver inflammation, YHG attenuated MCD-induced liver inflammation in mice. YHG also inhibited the activation of hepatic stellate cells (HSCs) and alleviated liver fibrosis in MCD-fed mice. Through nuclear factor erythroid 2-related factor 2 (Nrf2) signaling pathway, YHG alleviated liver oxidative stress injury in mice which induced by MCD. CONCLUSION: YHG ameliorated MCD-induced MAFLD in mice by reducing hepatic lipids accumulation, alleviating liver oxidative, inflammatory injury and attenuating hepatic fibrosis.


Assuntos
Medicamentos de Ervas Chinesas/farmacologia , Hepatopatia Gordurosa não Alcoólica , Animais , Dieta , Modelos Animais de Doenças , Fígado/metabolismo , Cirrose Hepática/tratamento farmacológico , Cirrose Hepática/metabolismo , Metionina , Camundongos , Camundongos Endogâmicos C57BL , Hepatopatia Gordurosa não Alcoólica/tratamento farmacológico , Hepatopatia Gordurosa não Alcoólica/metabolismo , Estresse Oxidativo
9.
Opt Express ; 28(24): 35588-35601, 2020 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-33379671

RESUMO

A method to realize pulse laser phase locking and homodyne detection is proposed, which can be used in lidar and continuous variable quantum key distribution (CVQKD) systems. Theoretical analysis shows that homodyne detection of pulse laser has a sensitivity advantage of more than 4 dB over heterodyne detection. An experimental verification setup was constructed to realize phase-locking and homodyne detection of pulse lasers at repetition rates from 50 kHz to 2.4 MHz. For 320 ns signal laser pulses at 300 kHz with peak power of -65 dBm, the phase error is 8.9° (mainly limited by the chirp effect in the modulation of signal laser), and the detection signal-to-noise ratio reaches 20.2 dB. When the peak power is reduced to -75 dBm, phase locking and homodyne detection can still be achieved. Homodyne detection based on phase locking could serve as a novel weak-laser-pulse receiving method with high sensitivity and anti-interference performance.

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