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Multi-Component Signal Processing for the Short Range Radar
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作者 李国林 施聚生 +1 位作者 赵曦 张旭 《Journal of Beijing Institute of Technology》 EI CAS 2000年第1期101-106,共6页
To study the measurement of distance under the condition of the frequency modulation (FM) multi component signal of a short range radar, the multi points scattering model of a target, the TLS ESPRIT (total least sq... To study the measurement of distance under the condition of the frequency modulation (FM) multi component signal of a short range radar, the multi points scattering model of a target, the TLS ESPRIT (total least square estimation of signal parameters via rotational invariance techniques) and the mathematical statistics methods were used. The method of computing single frequency signal's instantaneous frequency (IF) is unsuitable to the multi component signal. By using the method of the TLS ESPRIT combined with the mathematical statistics, the multi component signal's IF can be obtained. The computer simulation has shown that the method has the high accuracy for measuring the distance. 展开更多
关键词 short range radar multi component signal TLS-ESPRIT method instantaneous frequency(IF)
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Chirp-Rate Resolution of Fractional Fourier Transform in Multi-component LFM Signal 被引量:12
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作者 刘锋 黄宇 +1 位作者 陶然 王越 《Journal of Beijing Institute of Technology》 EI CAS 2009年第1期74-78,共5页
Distinguishing close chirp-rates of different linear frequency modulation (LFM) signals under concentrated and complicated signal environment was studied. Firstly, detection and parameter estimation of multi-compone... Distinguishing close chirp-rates of different linear frequency modulation (LFM) signals under concentrated and complicated signal environment was studied. Firstly, detection and parameter estimation of multi-component LFM signal were used by discrete fast fractional Fourier transform (FrFT). Then the expression of chirp-rate resolution in fractional Fourier domain (FrFD) was deduced from discrete normalize time-frequency distribution, when multi-component LFM signal had only one center frequency. Furthermore, the detail influence of the sampling time, sampling frequency and chirp-rate upon the resolution was analyzed by partial differential equation. Simulation results and analysis indicate that increasing the sampling time can enhance the resolution, but the influence of the sampling frequency can he omitted. What's more, in multi-component LFM signal, the chirp-rate resolution of FrFT is no less than a minimal value, and it mainly dependent on the biggest value of chirp-rates, with which it has an approximately positive exponential relationship. 展开更多
关键词 fractional Fourier transform(FrFT) RESOLUTION linear frequency modulation(LFM) signal chirp-rate
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Instantaneous frequency estimation of multi-component Chirp signals in noisy environments
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作者 WANG Bai-he HUANG Jian-guo 《Journal of Marine Science and Application》 2007年第4期13-17,共5页
A classical time-varying signal, the multi-component Chirp signal has been widely used and the ability to estimate its instantaneous frequency (IF) is very useful. But in noisy environments, it is hard to estimate t... A classical time-varying signal, the multi-component Chirp signal has been widely used and the ability to estimate its instantaneous frequency (IF) is very useful. But in noisy environments, it is hard to estimate the 1F of a multi-component Chirp signal accurately. Wigner distribution maxima (WDM) are usually utilized for this estimation. But in practice, estimation bias increases when some points deviate from the true IF in high noise environments. This paper presents a new method of multi-component Chirp signal 1F estimation named Wigner Viterbi fit (WVF), based on Wigner-Ville distribution (WVD) and the Viterbi algorithm. First, we transform the WVD of the Chirp signal into digital image, and apply the Viterbi algorithm to separate the components and estimate their IF. At last, we establish a linear model to fit the estimation results. Theoretical analysis and simulation results prove that this new method has high precision and better performance than WDM in high noise environments, and better suppression of interference and the edge effect. Compared with WDM, WVF can reduce the mean square error (MSE) by 50% when the signal to noise ration (SNR) is in the range of-15dB to -11dB. WVF is an effective and promising 1F estimation method. 展开更多
关键词 instantaneous frequency estimation multi-component Chirp signals Wigner-Villedistribution Viterbi algorithm linear fit
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Parameter Estimation of Multi-component Chirp Signal Based on Differential Evolution 被引量:3
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作者 ZHAO Haoran MENG Fankuo QIAO Liyan 《Instrumentation》 2017年第2期34-43,共10页
Chirp signals show energy aggregation in the fractional Fourier domain(FrFD) w hich can be used to estimate the parameter of the signals. In this paper,a parameter estimation method for multi-component chirp signal w ... Chirp signals show energy aggregation in the fractional Fourier domain(FrFD) w hich can be used to estimate the parameter of the signals. In this paper,a parameter estimation method for multi-component chirp signal w hich corrupted by w hite Gaussian noise is proposed based on the discrete fractional Fourier transform(DFrFT) and the differential evolution( DE) algorithm. The proposed algorithm uses the DE algorithm instead of the conventional fine search algorithm to detect the peak of the signals in the FrFD. The paper simulated the influence of the noise and the resolution of the proposed algorithm. The results of the simulation show the proposed method does not only improve the estimation accuracy of the peak coordinate,but also reduces time consuming. 展开更多
关键词 Chirp signal Fractional Fourier Transform Parameter Estimation Differential Evolution
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Novel multi-component synergistic bioink that balances biocompatibility and mechanical strength for cartilage regeneration
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作者 Zijun MA Wendan JIA +5 位作者 Xiaoyuan WANG Rong CHENG Lu HAN Meng LI Xiaoning YANG Shengbo SANG 《Journal of Zhejiang University-Science B(Biomedicine & Biotechnology)》 2025年第12期1156-1171,共16页
Hydrogels,owing to their porous network structure resembling the extracellular matrix(ECM),have become essential scaffold materials in the field of cartilage tissue engineering.Among them,gelatin methacrylate(GelMA)hy... Hydrogels,owing to their porous network structure resembling the extracellular matrix(ECM),have become essential scaffold materials in the field of cartilage tissue engineering.Among them,gelatin methacrylate(GelMA)hydrogels are widely used in bioink development due to their excellent biocompatibility,biodegradability,and tunable photo-crosslinking properties.However,the high biocompatibility of pure GelMA often comes at the cost of mechanical strength,limiting its applicability in cartilage regeneration.To overcome this trade-off,this study developed composite bioinks based on GelMA,silk fibroin(SF),and polyethylene oxide(PEO)for fabricating porous hydrogel scaffolds,which were then systematically characterized in terms of morphology,porosity,hydrophilicity,mechanical strength,rheological behavior,printability,and cytocompatibility.In this design,PEO serves as a porogen to generate highly porous structures(porosity up to 88%),while SF compensates for the mechanical loss caused by PEO,enabling the scaffold to retain a compression strength of up to 29.10 kPa.Among the tested formulations,the 10%GelMA/1%SF/1.5%PEO(1%=0.01 g/mL)bioink exhibited excellent printability,mechanical integrity,and cytocompatibility,and it supported a robust deposition of collagenⅡand aggrecan by chondrocytes after printing.This work provides a versatile strategy for balancing the biocompatibility and mechanical robustness in bioinks,offering a promising platform for next-generation cartilage tissue engineering scaffolds. 展开更多
关键词 Silk fibroin Polyethylene oxide multi-component collaboration Cartilage regeneration Tissue engineering
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Multi-component decompositions,linear superpositions,and new nonlinear integrable coupled KdV-type systems
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作者 Xiazhi Hao S Y Lou 《Communications in Theoretical Physics》 2025年第2期1-12,共12页
In the realm of nonlinear integrable systems,the presence of decompositions facilitates the establishment of linear superposition solutions and the derivation of novel coupled systems exhibiting nonlinear integrabilit... In the realm of nonlinear integrable systems,the presence of decompositions facilitates the establishment of linear superposition solutions and the derivation of novel coupled systems exhibiting nonlinear integrability.By focusing on single-component decompositions within the potential BKP hierarchy,it has been observed that specific linear superpositions of decomposition solutions remain consistent with the underlying equations.Moreover,through the implementation of multi-component decompositions within the potential BKP hierarchy,successful endeavors have been undertaken to formulate linear superposition solutions and novel coupled Kd V-type systems that resist decoupling via alterations in dependent variables. 展开更多
关键词 integrable system single-component decomposition multi-component decomposition linear superposition integrable coupled KdV-type system
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A facile high-efficiency preparation strategy for Al-containing multi-component boride microcrystals with superior comprehensive performance
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作者 Yong Fan Jinfeng Nie +7 位作者 Zhigang Ding Yujing Zhang Xiang Chen Wei Liu Sen Yang Sida Liu Xiangfa Liu Yonghao Zhao 《Journal of Materials Science & Technology》 2025年第1期190-203,共14页
Multi-component transition group metal borides(MMB_(2))have become a research hotspot due to their new composition design concepts and superior properties compared with conventional ceramics.Most of the current method... Multi-component transition group metal borides(MMB_(2))have become a research hotspot due to their new composition design concepts and superior properties compared with conventional ceramics.Most of the current methods,however,are complicated and time-consuming,the mass production remains a chal-lenge.Herein,we proposed a new high-efficiency strategy for synthesis of MMB_(2)using molten aluminum as the medium for the first time.The prepared Al-containing multi-component borides(TiZrHfNbTa)B_(2)microcrystals had a homogeneous composition with a hexagonal AlB_(2)structure and ultra-high hardness value of∼35.3 GPa,which was much higher than data reported in the literature and the rule of mix-ture estimations.Furthermore,combined with the First-principles calculation results,we found that the Poisson’s ratio(v)values exhibit a clearly ascending trend from 0.17 at VEC=3.5 to 0.18 at VEC=3.4,then to 0.201 at VEC=3.2 with the increasing of Al content.This indicates that the intrinsic toughness of multi-component boride microcrystals is obviously enhanced by the trace-doped Al elements.Besides,the fabricated Al-containing multi-component boride microcrystals have superior oxidation activation en-ergy and structural stability.The enhanced oxidation resistance is mainly attributed to the formation of a protective Al2 O3 oxide layer and the lattice distortion,both of which lead to sluggish diffusion of O_(2).These findings propose a new unexplored avenue for the fabrication of MMB_(2)materials with supe-rior comprehensive performance including ultra-hardness and intrinsically improved thermo-mechanical properties. 展开更多
关键词 multi-component borides First-principles calculations Crystal growth Mechanical properties Oxidation behavior
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Uncovering the hardening mechanism of multi-component carbide ceramics based on the coupling effect of covalent bond enhancement and lattice distortion
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作者 Qingyi Kong Qinchen Liu +7 位作者 Lei Chen Sijia Huo Kunxuan Li Mingxuan Mao WeiWei Sun Yujin Wang Suk-Joong L.Kang Yu Zhou 《Journal of Materials Science & Technology》 2025年第31期102-112,共11页
The hardening mechanism of multi-component carbide ceramic has been investigated in detail through a combination of experiments,first-principles calculations,and ab initio molecular dynamics(AIMD).Eight dense carbide ... The hardening mechanism of multi-component carbide ceramic has been investigated in detail through a combination of experiments,first-principles calculations,and ab initio molecular dynamics(AIMD).Eight dense carbide ceramics were prepared by spark plasma sintering.Compulsorily,all the multi-component carbide samples have similar carbon content,grain size,and uniform compositional distribution by optimizing the sintering process and adjusting the initial raw materials.Hence the interference of other factors on the hardness of multi-component carbide ceramics is minimized.The effects of changes in the elemental species on the lattice distortion,bond strength,bonding properties,and electronic structure of multi-component carbide ceramics were thoroughly analyzed.These results show that the hardening of multi-component carbide ceramic can be attributed to the coupling of solid solution strengthening caused by lattice distortion and covalent bond strengthening.Besides,the“host lattice”of multi-component carbide ceramics is defined based on the concept of supporting lattice.The present work is of great significance for a deeper understanding of the hardening mechanism of multi-component carbide ceramics and the design of superhard multi-component carbides. 展开更多
关键词 multi-component ceramics Mechanical properties Hardening mechanism First principle calculation Ab initio molecular dynamics
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Photocatalytic multi-component synthesis of ester-containing quinoxalin-2(1H)-ones using water as the hydrogen donor
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作者 Qiang Feng Jindong Hao +3 位作者 Ya Hu Rong Fu Wei Wei Dong Yi 《Chinese Chemical Letters》 2025年第6期484-488,共5页
A convenient photocatalytic multi-component reaction of alkenes,quinoxalin-2(1H)-ones,and diazo compounds has been developed in the presence of water.A number of ester-containing quinoxalin-2(1H)-ones could be efficie... A convenient photocatalytic multi-component reaction of alkenes,quinoxalin-2(1H)-ones,and diazo compounds has been developed in the presence of water.A number of ester-containing quinoxalin-2(1H)-ones could be efficiently obtained in moderate to good yields at room temperature.This metal-free visiblelight-driven tandem reaction was conducted through proton-coupled electron transfer(PCET)process using water as the hydrogen donor and 1,2,3,5-tetrakis(carbazol-9-yl)-4,6-dicyanobenzene(4CzIPN)as the photocatalyst. 展开更多
关键词 PHOTOCATALYTIC multi-component synthesis Diazo compounds Radical reaction Quinoxalin-2(1H)-ones
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Oncogenic Ras,Yki and Notch signals converge to confer clone competitiveness through Upd2
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作者 Ying Wang Rui Huang +6 位作者 Minfeng Deng Jingjing He Mingxi Deng Toyotaka Ishibashi Cong Yu Zongzhao Zhai Yan Yan 《Journal of Genetics and Genomics》 2026年第1期110-120,共11页
Cell competition is an evolutionarily ancient mechanism that functions to remove unfit or dangerous clonal cells in a multicellular community.A classical model is the removal of polarity-deficient clones,such as the p... Cell competition is an evolutionarily ancient mechanism that functions to remove unfit or dangerous clonal cells in a multicellular community.A classical model is the removal of polarity-deficient clones,such as the precancerous scribble(scrib)mutant clones,in Drosophila imaginal discs.The activation of Ras,Yki,or Notch signaling robustly reverses the scrib mutant clonal fate from elimination to tumorous growth.Whether these signals converge to adopt a common mechanism to overcome the elimination pressure posed by cell competition remains unclear.Using single-cell transcriptomics,we find that a critical converging point downstream of Ras,Yki,and Notch signals is the upregulation of Upd2,an IL-6 family cytokine.Overexpression of Upd2 is sufficient to rescue the scrib mutant clones from elimination.Depletion of Upd2 blocks the growth of the scrib mutant clones with active Ras,Yki,and Notch signals.Moreover,Upd2 overexpression promotes robust intestinal stem cell(ISC)proliferation,while Upd2 is intrinsically required in ISCs for the growth of the adult intestine.Together,these results identify Upd2 as a crucial cell fitness factor that sustains tissue growth but can potentiate tumorigenesis when deregulated. 展开更多
关键词 Drosophila melanogaster Cell competition Single-cell transcriptomics Notch signaling Ras signaling Hippo signaling
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Enhancing Convolution Recurrent Network with Graph Signal Processing:High Suppressive Interference Mitigation
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作者 Guo Pengcheng Yu Miao +1 位作者 Gu Miaomiao Ren Bingyin 《China Communications》 2026年第1期255-272,共18页
In this paper,we propose a novel graph signal processing convolution recurrent network(GSP CRN)for signal enhancement against high suppressive interference(HSI)in wireless communications.GSPCRN consists of the short-t... In this paper,we propose a novel graph signal processing convolution recurrent network(GSP CRN)for signal enhancement against high suppressive interference(HSI)in wireless communications.GSPCRN consists of the short-time graph signal processing(SGSP)approach and a modified convolution recurrent network.Similar to the traditional shorttime time-frequency transformation,SGSP frames the complex-valued communication signal and transforms it to the graph-domain representations,where the connection and weight flexibility of each vertex are fully taken into account.In the presence of HSI,SGSP can extract signal features from new graph-domain dimensions and empower neural networks for weak signal enhancement.Two SGSP methods,adjacency singular value decomposition and implicit graph transformation,are designed to capture relationships among the sampling points in the segmented signals.Simulation results demonstrate that our proposed GSPCRN outperforms existing classic methods in extracting weak signals from the HSI environment.When the interference-to-signal ratio exceeds 27dB,only our proposed GSPCRN can achieve the interference mitigation. 展开更多
关键词 adjacency matrix short-time graph signal processing signal enhancement wireless communications
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Integrated multi-omics dissects receptor-mediated phytomelatonin signaling
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作者 Ying Liu Shirui Jing +5 位作者 Yuhao Zheng Qiuyu He Chengcheng Shen Junxin Guo Yangdong Guo Na Zhang 《Horticultural Plant Journal》 2026年第2期485-488,共4页
Phytomelatonin,an emerging plant hormone,plays vital roles in plant growth,development,and stress adaptation(Arnao et al.,2022;Ullah et al.,2024).It acts both as a direct antioxidant and a signaling molecule,engaging ... Phytomelatonin,an emerging plant hormone,plays vital roles in plant growth,development,and stress adaptation(Arnao et al.,2022;Ullah et al.,2024).It acts both as a direct antioxidant and a signaling molecule,engaging complex networks and interacting with other phytohormones(Liu et al.,2022;Khan et al.,2023).Although phytomelatonin receptors(PMTRs)have been identified in many plants(Wei et al.,2018;Wang et al.,2022;Liu et al.,2025),the downstream signaling mechanisms,particularly receptor-mediated protein modifications and transcriptional regulation,remain poorly characterized. 展开更多
关键词 phytomelatonin receptors pmtrs transcriptional regulation signaling moleculeengaging complex networks integrated multi omics PHYTOHORMONES protein modifications plant hormoneplays phytomelatonin signaling
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SMAD7 regulates the canonical Wnt signaling through TGF-β cascade crosstalk and SMAD7/β-CATENIN transcription factor complex formation during tooth regeneration
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作者 Qiuyu Chen Zhi Liu +4 位作者 Bohuai Zhou Cheng Liang Yiping Chen Weidong Tian Tian Chen 《International Journal of Oral Science》 2026年第1期103-114,共12页
Tooth morphogenesis is orchestrated by a complex interplay of signaling pathways and transcription factors that control cell proliferation,apoptosis,and differentiation,with the Wnt/β-catenin signaling pathway playin... Tooth morphogenesis is orchestrated by a complex interplay of signaling pathways and transcription factors that control cell proliferation,apoptosis,and differentiation,with the Wnt/β-catenin signaling pathway playing a pivotal role.However,the comprehensive regulatory mechanisms of Wnt/β-catenin signaling remain largely unclear.Smad7,a key antagonist of the TGF-βsuperfamily,is essential for maintaining tissue homeostasis and ensuring proper cellular function.Our previous study has demonstrated that Smad7 knockout in mice leads to impaired proliferative property of tooth germ cells,resulting in small molars.Here,we identified SMAD7 expression in human dental papilla and dental pulp,colocalized with β-CATENIN and cell proliferationrelated proteins.RNA sequencing analysis revealed a significant reduction in Wnt signaling activity in Smad7-deficient mouse tooth germs.Using lentivirus transfection,we established SMAD7-knockdown human dental papilla stem cells,which manifested remarkably blunt proliferation rate,along with diminished Wnt signaling activity.In vivo transplantation investigations further revealed the indispensable role of SMAD7 in dentin formation.Mechanistically,we revealed that β-CATENIN interacts with P-SMAD2/3 and SMAD7 through co-immunoprecipitation and yeast two-hybrid assays.Inhibition of TGF-β pathway or disruption of SMAD7/β-CATENIN transcription factor complex formation potently impacted Wnt/β-catenin activities,indicating both direct and indirect regulatory mechanisms.These findings highlight the critical role of SMAD7 in the proliferation and diffe rentiation of human dental stem cells,which could contribute to dental tissue regeneration and engineering. 展开更多
关键词 Dental stem cells Wnt catenin signaling signaling pathways transcription factors Tooth regeneration tooth morphogenesis maintaining tissue homeostasis TGF cascade
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Optimal Control-Based Small Signal Stability Analysis of Power System Incorporating Flexible AC Transmission System and Electric Vehicle Load
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作者 Naveen Guguloth Bishwajit Dey +2 位作者 Fausto Pedro García Márquez Prasenjit Dey Isaac Segovia Ramírez 《Energy Engineering》 2026年第3期546-587,共42页
The increasing integration of electric vehicle(EV)loads into power systems necessitates understanding their impact on stability.Small-magnitude perturbations,if persistent,can cause low-frequency oscillations,leading ... The increasing integration of electric vehicle(EV)loads into power systems necessitates understanding their impact on stability.Small-magnitude perturbations,if persistent,can cause low-frequency oscillations,leading to synchronism loss and mechanical stress.This work analyzes the effect of voltage-dependent EV loads on this small-signal stability.The study models an EV load within a Single-Machine Infinite Bus(SMIB)system.It specifically evaluates the influence of EV charging through the DC link capacitor of a Unified Power Flow Controller(UPFC),a key device for damping oscillations.The system’s performance is compared to a modified version equipped with both a UPFC and a Linear Quadratic Regulator(LQR)controller.Results confirm the significant influence of EV charging on the power network.The analysis demonstrates that the best performance is achieved with the SMIB system utilizing the combined UPFC and LQR controller.This configuration effectively dampens low-frequency oscillations,yielding superior results by reducing the system’s rise time,settling time,and peak overshoot. 展开更多
关键词 Power system SMIB LQR EV small signal stability UPFC
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Hederagenin Alleviated Ovariectomy-Induced Bone Loss through the Regulation of Innate Immune Signaling in Mice
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作者 Zhitao Yang Huanyu Cheng +11 位作者 Xinli Liu JieLi Xin Ming Beibei Li Luyao Zhang Chunqing Ma Yi Jiao Shenjia Wu Ibrar Muhammad Khan Guanghua Xiong Hongcheng Wang Yong Liu 《BIOCELL》 2026年第1期232-247,共16页
Objectives:Postmenopausal osteoporosis is the most common form of osteoporosis in clinical practice,affecting millions of postmenopausal women worldwide.Postmenopausal osteoporosis demands safe and effective therapies... Objectives:Postmenopausal osteoporosis is the most common form of osteoporosis in clinical practice,affecting millions of postmenopausal women worldwide.Postmenopausal osteoporosis demands safe and effective therapies.This study aimed to evaluate the potential of hederagenin(Hed)for treating osteoporosis and to elucidate its underlying mechanisms of action.Methods:The anti-osteoporotic potential of Hed was assessed by investigating its effects on ovariectomy(OVX)-induced bone loss in mice and on receptor activator of NF-kappaB ligand(RANKL)-induced osteoclast differentiation in RAW264.7 cells.Network pharmacology analysis and molecular docking were employed to identify key targets,which were subsequently validated experimentally.Results:In vitro,Hed suppressed osteoclastogenesis by inhibiting the formation of osteoclasts and F-actin rings and by down-regulating osteoclastspecific genes(Atp6v0d2 and Acp5).In vivo,Hed significantly amelioratedOVX-induced bone loss,restoring trabecular bone volume fraction(BV/TV)and trabecular number(Tb.N),while reducing trabecular separation(Tb.Sp).Network pharmacology analysis identified 142 overlapping targets linking Hed to osteoporosis,including tumor necrosis factor alpha(TNF-α),interleukin-6(IL-6),and IL-1β,with enrichment in innate immune signaling and osteoclast differentiation.Molecular docking analysis indicated strong binding affinities between Hed and targets such as TNF-α,IL-6,and IL-1β.Experimentally,Hed was found to decrease RANKL,elevate osteoprotegerin(OPG),and suppress intestinalmRNA levels of pro-inflammatory cytokines such as IL-1β,IL-6,IL-17A,and TNF-α.Conclusion:Hed exerts significant anti-osteoporotic effects inOVX-induced osteoporosis through a dualmechanism involving the suppression of both osteoclastogenesis and innate immune signaling pathways.These findings highlighted Hed’s novel role in modulating immune-bone crosstalk,offering a promising strategy for treating osteolytic diseases without estrogenic side effects. 展开更多
关键词 HEDERAGENIN OSTEOPOROSIS innate immune signaling OSTEOCLASTOGENESIS network pharmacology
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Phasemeter based on second harmonic signal filter for space-based gravitational wave detection
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作者 Zheng Fan Zhu Li +7 位作者 Xiangqing Huang Yurong Liang Yu Song Maomao Fan Huizong Duan Siyuan Peng Shanqing Yang Liangcheng Tu 《Chinese Physics B》 2026年第1期159-168,共10页
The space gravitational wave detection aims to detect gravitational waves in the mHz band in order to study supermassive black hole mergers,galaxy evolution and the structure of the early universe.One of its core payl... The space gravitational wave detection aims to detect gravitational waves in the mHz band in order to study supermassive black hole mergers,galaxy evolution and the structure of the early universe.One of its core payloads is a transponder-type interstellar laser interferometer,designed to measure relative displacement changes at the pico-meter level.Among its components,phasemeter is tasked with extracting the phase and frequency of the interference signal.Currently,phase-locked loop(PLL)phasemeters are commonly employed.However,the second harmonic signal generated by the mixer can restrict both the dynamic range and phase measurement accuracy of the phasemeter.This paper analyzes the interstellar laser interferometer and the impact of the second harmonic signal on the phasemeter's performance.To address these challenges,a phasemeter incorporating a second harmonic signal filter is proposed.This new design mitigates second harmonic disturbances within the phasemeter's bandwidth by dynamically adjusting the filter's cutoff frequency to track the input signal frequency,thereby suppressing the second harmonic signal in real time.Theoretical and simulation analyses demonstrate that the proposed phasemeter with a second harmonic filter significantly enhances the dynamic range.Finally,experimental results verify that the phasemeter can achieve the tracking of sudden frequency changes up to4.8 MHz. 展开更多
关键词 laser interferometer phasemeter second harmonic signal dynamic range
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Rhpn2 regulates the development and function of vestibular sensory hair cells through the RhoA signaling in zebrafish
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作者 Yubei Dai Qianqian Li +7 位作者 Jiaju Deng Sihang Wu Guiyi Zhang Yuebo Hu Yuqian Shen Dong Liu Han Wu Jie Gong 《Journal of Genetics and Genomics》 2026年第1期131-142,共12页
Hearing and balance disorders are significant health issues primarily caused by developmental defects or the irreversible loss of sensory hair cells(HCs).ldentifying the underlying genes involved in the morphogenesis ... Hearing and balance disorders are significant health issues primarily caused by developmental defects or the irreversible loss of sensory hair cells(HCs).ldentifying the underlying genes involved in the morphogenesis and development of HCs is crucial.Our current study highlights rhpn2,a member of rho-binding proteins,as essential for vestibular HC development.The rhpn2 gene is highly expressed in the crista and macula HCs.Loss of rhpn2 function in zebrafish reduces the otic vesicle area and vestibular HC number,accompanied by vestibular dysfunction.Shorter stereocilia and compromised mechanotransduction channel function are found in the crista HCs of rhpn2 mutants.Transcriptome RNA sequencing analysis predicts the potential interaction of rhpn2 with rhoab.Furthermore,co-immunoprecipitation confirms that Rhpn2 directly binds to RhoA,validating the interaction of the two proteins.rhpn2 knockout leads to a decreased expression of rock2b,a canonical RhoA signaling pathway gene.Treatment with the RhoA activator or exogenous rock2b mRNA injection mitigates crista HC stereocilia defects in rhpn2 mutants.This study uncovers the role of rhpn2 in vestibular HC development and stereocilia formation via mediating the RhoA signaling pathway,providing a target for the treatment of balance disorders. 展开更多
关键词 STEREOCILIA Balance disorder RhoA signaling Crista hair cell ZEBRAFISH
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Kaempferol protects against dexamethasone-induced muscle atrophy in mice by increasing PI3K/AKT/mTOR and NRF2/HO-1/KEAP1 signaling pathways:network pharmacology,molecular docking,and experimental validation studies
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作者 Ming Zhang Guofei Chang +6 位作者 Shouzheng Gao Jiuying Wei Minmin Chen Ling Song Juan Lu Jun Sheng Xiao Ma 《Food Science and Human Wellness》 2026年第2期851-868,共18页
Muscle atrophy can be induced by high doses or prolonged use of glucocorticoids.Kaempferol(Kae)is a naturally occurring flavonoid with a variety of biological activities and the effect of Kae on dexamethasone(Dex)indu... Muscle atrophy can be induced by high doses or prolonged use of glucocorticoids.Kaempferol(Kae)is a naturally occurring flavonoid with a variety of biological activities and the effect of Kae on dexamethasone(Dex)induced muscle atrophy in animals has not been elucidated.To explore this issue,the present experiments used a computationally assisted drug design scheme combining network pharmacology,molecular docking and in vivo experiments to investigate the mechanism of Kae against muscle atrophy.Network pharmacological analyses revealed 275 potential targets for Kae and 12294 potential targets for muscle atrophy,with a total of 228 crosstargets for Kae and muscle atrophy.GO and KEGG analyses were performed based on the protein-protein interaction(PPI)network of muscle atrophy and Kae component targets.The GO results showed that the biological processes were mainly related to the metabolic process of reactive oxygen species,and the response to oxidative stress;the cellular components were mainly focused on membrane microdomains,and membrane regions;the molecular functions mainly worked on phosphatase binding;and the KEGG pathway enrichment analyses identified the pathways of interaction between Kae and muscle atrophy.Finally,as verified by in vivo experiments,Kae may reduce the onset of muscle atrophy by activating the PI3K/AKT/m TOR/signalling pathway,inhibiting Foxo1/Foxo3 activity,and inhibiting downstream production of the ubiquitination 3 ligases Atrogin1 and Mu RF1;Kae also promotes the expression of NRF2/HO-1/KEAP1 signalling pathway,enhances muscle antioxidant capacity,inhibits the release of COX-2 and TNF-αinflammatory factors,and reduces the damage caused by oxidative stress and inflammatory factors to muscles.Therefore,there may be a synergistic effect of PI3K/AKT/m TOR and NRF2/HO-1/KEAP1 in Kae working together to prevent muscle atrophy.The binding energy and stability of Kae to potential targets were examined by molecular docking and molecular dynamics simulations,implying that Kae could be used for the prevention and treatment of muscle atrophy in patients. 展开更多
关键词 KAEMPFEROL DEXAMETHASONE Muscle atrophy PI3K/AKT/mTOR signaling pathway NRF2/HO-1/KEAP1 signaling pathway
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RAF1 in AgRP neurons involved in the regulation of energy metabolism via the MAPK signaling pathway
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作者 Yuqian Chen Lianci Ren +5 位作者 Xinyi Xu Zhenning Sun Mingxi Dai Yin Li Xiang Ma Juxue Li 《Journal of Biomedical Research》 2026年第1期45-62,共18页
V-raf-leukemia viral oncogene 1(RAF1),a serine/threonine protein kinase,is well established to play a crucial role in tumorigenesis and cell development.However,the specific role of hypothalamic RAF1 in regulating ene... V-raf-leukemia viral oncogene 1(RAF1),a serine/threonine protein kinase,is well established to play a crucial role in tumorigenesis and cell development.However,the specific role of hypothalamic RAF1 in regulating energy metabolism remains unknown.In this study,we found that the expression of RAF1 was significantly increased in hypothalamic AgRP neurons of diet-induced obesity(DIO)mice.Under normal chow diet feeding,overexpression of Raf1 in AgRP neurons led to obesity in mice characterized by increased body weight,fat mass,and impaired glucose tolerance.Conversely,Raf1 knockout in AgRP neurons protected against diet-induced obesity,reducing fat mass and improving glucose tolerance.Mechanistically,Raf1 activated the MAPK signaling pathway,culminating in the phosphorylation of cAMP response element-binding protein(CREB),which enhanced transcription of Agrp and Npy.Insulin stimulation further potentiated the RAF1-MEK1/2-ERK1/2-CREB axis,highlighting RAF1's role in integrating hormonal and nutritional signals to regulate energy balance.Collectively,these findings underscore the important role of RAF1 in AgRP neurons in maintaining energy homeostasis and obesity pathogenesis,positioning it and its downstream pathways as potential therapeutic targets for innovative strategies to combat obesity and related metabolic diseases. 展开更多
关键词 RAF1 AgRP neurons MAPK signaling pathway CREB OBESITY
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The signaling pathways of atherosclerosis regulated by Taohong Siwu Decoction
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作者 Kaijie Yan Sihe Gong +4 位作者 Yanni Li Zhonghong Shi Yimin Bao Jing Leng Ke Ning 《Chinese Journal of Natural Medicines》 2026年第3期279-288,共10页
Taohong Siwu Decoction(THSWD), a traditional Chinese medicinal formulation, has been demonstrated to significantly modulate key signaling pathways implicated in atherosclerosis(AS). This review examines the complex me... Taohong Siwu Decoction(THSWD), a traditional Chinese medicinal formulation, has been demonstrated to significantly modulate key signaling pathways implicated in atherosclerosis(AS). This review examines the complex mechanisms through which THSWD influences critical pathways, including nuclear factor kappa-B(NF-κB), phosphatidylinositol 3-kinase(PI3K)/serine-threonine kinase(AKT), Toll-like receptor 4(TLR4), mitogen-activated protein kinase(MAPK), and mammalian target of rapamycin(mTOR), that play pivotal roles in AS pathogenesis. By synthesizing experimental evidence and existing literature, the review summarizes how THSWD and its bioactive constituents regulate these signaling cascades to ameliorate AS. Furthermore, it highlights the distinctive therapeutic advantages of traditional Chinese medicine(TCM) compounds in managing chronic diseases driven by multi-target and multifactorial mechanisms. Analyzing disease targets from the perspective of signaling pathways enhances the scientific validation of clinical efficacy for such formulations, thereby offering novel insights for future research. 展开更多
关键词 ATHEROSCLEROSIS Traditional Chinese medicine Taohong Siwu Decoction signaling pathways
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