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Acoustic Based Crosshole Full Waveform Slowness Inversion in the Time Domain 被引量:2
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作者 Wensheng Zhang Atish Kumar Joardar 《Journal of Applied Mathematics and Physics》 2018年第5期1086-1110,共25页
We develop a new full waveform inversion (FWI) method for slowness with the crosshole data based on the acoustic wave equation in the time domain. The method combines the total variation (TV) regularization with the c... We develop a new full waveform inversion (FWI) method for slowness with the crosshole data based on the acoustic wave equation in the time domain. The method combines the total variation (TV) regularization with the constrained optimization together which can inverse the slowness effectively. One advantage of slowness inversion is that there is no further approximation in the gradient derivation. Moreover, a new algorithm named the skip method for solving the constrained optimization problem is proposed. The TV regularization has good ability to inverse slowness at its discontinuities while the constrained optimization can keep the inversion converging in the right direction. Numerical computations both for noise free data and noisy data show the robustness and effectiveness of our method and good inversion results are yielded. 展开更多
关键词 ACOUSTIC Wave Equation CROSSHOLE Full WAVEFORM INVERSION slowness BOUND Constraints TV Regularization
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Estimation of azimuth and slowness of teleseismic signals recorded by a local seismic network
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作者 JIN Ping(靳平) +1 位作者 PAN Chang-zhou(潘常周) 《Acta Seismologica Sinica(English Edition)》 CSCD 2002年第6期646-655,共10页
A new method that is applicable to local seismic networks to estimate the azimuth and slowness of teleseismic signals is introduced in the paper. The method is based on the correlation between the arrival times and st... A new method that is applicable to local seismic networks to estimate the azimuth and slowness of teleseismic signals is introduced in the paper. The method is based on the correlation between the arrival times and station positions. The analyzed results indicate that the azimuth and slowness of teleseismic signals can be accurately estimated by the method. Average errors for azimuth and slowness measurements obtained by this method using data of Xian Digital Telemetry Seismic Network are 2.0?and 0.34 s/(?, respectively. The conclusions drawn from this study indicate that this method may be very useful to interpret teleseismic records of local seismic networks. 展开更多
关键词 local station network teleseismic event AZIMUTH slowness
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Huangqi decoction ameliorated intestinal barrier dysfunction via regulating NF-κB signaling pathway in slow transit constipation model mice 被引量:1
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作者 Hua-Xian Chen Guo-Zhong Xiao +7 位作者 Chao-Xin Yang Yi-Hui Zheng Ming-Yuan Lei Hao Xu Dong-Lin Ren Liang Huang Qiu-Lan He Hong-Cheng Lin 《World Journal of Gastrointestinal Surgery》 2025年第5期283-303,共21页
BACKGROUND The development of slow transit constipation(STC)is associated with intestinal barrier damage.Huangqi decoction(HQD)is effective in treating STC,but me-chanisms are unclear.AIM To investigate whether HQD al... BACKGROUND The development of slow transit constipation(STC)is associated with intestinal barrier damage.Huangqi decoction(HQD)is effective in treating STC,but me-chanisms are unclear.AIM To investigate whether HQD alleviates STC by downregulating the nuclear factorκB(NF-κB)signaling pathway and restoring intestinal barrier function.METHODS KM mice were divided into control,model,and HQD treatment groups.Fresh colonic tissues were collected for single-cell RNA sequencing and spatial tra-nscriptome sequencing.The expressions of claudin-1,mucin 2,and NF-κB P65 proteins were detected by immunohistochemistry.In vitro experiments evaluated the effects of HQD on the LS174T cell line.RESULTS HQD improved intestinal motility,restored mucosal epithelium function and morphology.Single-cell RNA sequencing and spatial transcriptome sequencing data showed a reduction in goblet cells,decreased mucin 2 secretion,and activated apoptotic pathways in STC mice.The population of intestinal stem cells was reduced,and proliferation along with Wnt/β-catenin pathways were inhibited.STC also altered the distribution of intestinal cell states,increasing immune-associated Enterocyte_C3.Aberrant NF-κB pathway activation was noted across various cell types.After HQD treatment,NF-κB pathway activity was down-regulated,while cell proliferation pathways were up-regulated,alongside an increase in Enterocyte_C1 related to material transport.Immunocytochemical,Western blot,and immunohistochemistry analyses confirmed NF-κB pathway activation in goblet cells of STC mice,with HQD inhibiting this aberrant activation.CONCLUSION STC involves intestinal mucosal barrier damage.HQD may treat STC by suppressing NF-κB signaling in epithelial cells,restoring intestinal epithelial cell function,and promoting mucosal barrier repair. 展开更多
关键词 Slow transit constipation Huangqi decoction Multi-omics Intestinal barrier dysfunction Protective effects
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Exploring kink strengthening in WZ21 magnesium alloy via slow solidification and extrusion
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作者 Drahomír Dvorský Yoshihito Kawamura +7 位作者 Shin-Ichi Inoue Soya Nishimoto JiríKubásek Anna Boukalová Miroslav Cavojský Luděk Heller Jan Duchoň Dalibor Vojtěch 《Journal of Magnesium and Alloys》 2025年第5期2155-2173,共19页
The Mg-Y-Zn magnesium alloy system is known for the presence of Long-Period Stacking Ordered(LPSO)phases that improves strength and ductility with minimal amounts of alloying elements.Even better improvements are asso... The Mg-Y-Zn magnesium alloy system is known for the presence of Long-Period Stacking Ordered(LPSO)phases that improves strength and ductility with minimal amounts of alloying elements.Even better improvements are associated with the specific microstructure known as the Mille-Feuille(MF)structure that can occur in this alloy as well after proper heat treatment.This study systematically compares the traditional ingot metallurgy method with the Bridgman method(slow cooling),coupled with diverse heat treatments and extrusion process.Microscopic analyses reveal variations in the presence of LPSO phases,MF structure,and especially grain size,leading to divergent mechanical and corrosion properties.The Bridgman approach surprisingly stands out,ensuring superior mechanical properties due to kink and texture strengthening. 展开更多
关键词 Slow solidification EXTRUSION KINK Mechanical properties Mille-Feuille Corrosion
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A Comparative Study and Appreciation of Translations of Slow, Slow Tune from the Perspective of Translation Aesthetics
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作者 ZHANG Wen-bo 《Journal of Literature and Art Studies》 2025年第3期142-147,共6页
Under the perspective of translation aesthetics,the article studies three Chinese-to-English translations of Slow,Slow Tune as research objects,comparing and contrasting the differences between the different translati... Under the perspective of translation aesthetics,the article studies three Chinese-to-English translations of Slow,Slow Tune as research objects,comparing and contrasting the differences between the different translations under the perspective of translation aesthetics.The study finds that:Kenneth Rexroth’s translation is poor in textual understanding,with a lot of errors,and is too shallow in emotional expression,remaining only on the surface of the text;Lin Yutang makes occasional mistakes in understanding individual words,and is able to explore the implicit feelings of the lyricist,and his translation focuses on textual and phonological beauty;Xu Yuanchong’s translation is not only capable of conveying the meaning of the original work,but also of conveying the lyricist’s feelings more vividly and focusing on the phonological beauty.Xu Yuanchong’s translation not only conveys the meaning of the original work,but also vividly conveys the emotion of the lyricist,and pays attention to the beauty of sound. 展开更多
关键词 translation aesthetics SLOW Slow Tune
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CC-OLIA:A dynamic congestion control algorithm for multipath QUIC in mobile networks
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作者 Haoyu Wang Yang Liu +5 位作者 Zijun Li Yu Zhang Wenjing Gong Tao Jiang Ting Bi Jiaxi Zhou 《Digital Communications and Networks》 2025年第4期1180-1190,共11页
High-quality services in today’s mobile networks require stable delivery of bandwidth-intensive network content.Multipath QUIC(MPQUIC),as a multipath protocol that extends QUIC,can utilize multiple paths to support s... High-quality services in today’s mobile networks require stable delivery of bandwidth-intensive network content.Multipath QUIC(MPQUIC),as a multipath protocol that extends QUIC,can utilize multiple paths to support stable and efficient transmission.The standard coupled congestion control algorithm in MPQUIC synchronizes these paths to manage congestion,meeting fairness requirements and improving transmission efficiency.However,current algorithms’Congestion Window(CWND)reduction approach significantly decreases CWND upon packet loss,which lowers effective throughput,regardless of the congestion origin.Furthermore,the uncoupled Slow-Start(SS)in MPQUIC leads to independent exponential CWND growth on each path,potentially causing buffer overflow.To address these issues,we propose the CC-OLIA,which incorporates Packet Loss Classifcation(PLC)and Coupled Slow-Start(CSS).The PLC distinguishes between congestion-induced and random packet losses,adjusting CWND reduction accordingly to maintain throughput.Concurrently,the CSS module coordinates CWND growth during the SS,preventing abrupt increases.Implementation on MININET shows that CC-OLIA not only maintains fair performance but also enhances transmission efficiency across diverse network conditions. 展开更多
关键词 MPQUIC Mobile network Congestion control Packet loss Slow start
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Atomic-Level Understanding of Contact Potential of Quartz Surface
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作者 Lina Ma 《Journal of Architectural Research and Development》 2025年第2期68-74,共7页
Laboratory and field observations have suggested a correlation between contact dynamics and slow dynamics.The underlying mechanical mechanisms at the contact level require investigation at the nanoscale.This study use... Laboratory and field observations have suggested a correlation between contact dynamics and slow dynamics.The underlying mechanical mechanisms at the contact level require investigation at the nanoscale.This study uses molecular dynamics(MD)simulations to investigate the interactions between two quartz plates separated by a water film,focusing on the relationship between adhesion force and separation distance.The density and orientation angle profiles were calculated from simulation data to investigate the relationship between the interfacial structure of the water film and contact potential.The simulations reveal multiple metastable states of the contact potential,consistent with existing theoretical models.The results show that the contact force is influenced by the structure of the water film,including oscillation forces and stratification.This provided verification and development for existing theoretical models based on metastable contacts. 展开更多
关键词 QUARTZ Molecular simulation ADHESION Multiple metastable states Slow dynamics
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Competitive roles of slow/delta oscillation-nesting-mediated sleep disruption under acute methamphetamine exposure in monkeys
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作者 Xin LV Jie LIU +6 位作者 Shuo MA Yuhan WANG Yixin PAN Xian QIU Yu CAO Bomin SUN Shikun ZHAN 《Journal of Zhejiang University-Science B(Biomedicine & Biotechnology)》 2025年第7期694-707,共14页
Abuse of amphetamine-based stimulants is a primary public health concern.Recent studies have underscored a troubling escalation in the inappropriate use of prescription amphetamine-based stimulants.However,the neuroph... Abuse of amphetamine-based stimulants is a primary public health concern.Recent studies have underscored a troubling escalation in the inappropriate use of prescription amphetamine-based stimulants.However,the neurophysiological mechanisms underlying the impact of acute methamphetamine exposure(AME)on sleep homeostasis remain to be explored.This study employed non-human primates and electroencephalogram(EEG)sleep staging to evaluate the influence of AME on neural oscillations.The primary focus was on alterations in spindles,delta oscillations,and slow oscillations(SOs)and their interactions as conduits through which AME influences sleep stability.AME predominantly diminishes sleep-spindle waves in the non-rapid eye movement 2(NREM2)stage,and impacts SOs and delta waves differentially.Furthermore,the competitive relationships between SO/delta waves nesting with sleep spindles were selectively strengthened by methamphetamine.Complexity analysis also revealed that the SO-nested spindles had lost their ability to maintain sleep depth and stability.In summary,this finding could be one of the intrinsic electrophysiological mechanisms by which AME disrupted sleep homeostasis. 展开更多
关键词 AMPHETAMINE Sleep stage Slow oscillation(SO) Delta oscillation Addiction Electroencephalogram(EEG)
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Experimental study on strain localization and slow deformation evolution in small‑scale specimens
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作者 Fayuan Yan Enzhi Wang +2 位作者 Xiaoli Liu Chengzhi Qi Wei Jia 《International Journal of Coal Science & Technology》 2025年第2期245-254,共10页
A kind of slow deformation wave is produced in the crust under the action of internal and external factors,which plays an important role in the formation and occurrence of earthquakes.In this paper,uniaxial compressio... A kind of slow deformation wave is produced in the crust under the action of internal and external factors,which plays an important role in the formation and occurrence of earthquakes.In this paper,uniaxial compression tests are carried out on red sandstone samples with uniform texture.Displacement controlled loading methods are adopted,and the loading rates are 0.1 mm/min,0.5 mm/min and 1.0 mm/min,respectively.The micro-characterization method of speckle photography and DIC processing technology are adopted.The transfer characteristics of slow deformation and strain localization of red sandstone specimens during loading and deformation are discussed.The results show that the boundary advance velocity is proportional to the slow deformation transfer velocity with the change of position,so it can be considered that the slow deformation transfer velocity is equal to the particle motion transfer velocity.The formation and development of sample strain localization may be determined by the flow channel,nucleation and Luders zone evolution.The formation of the Luders band is related to the maximum value of the flow channel,and as deformation increases,the Luders band merges and develops with the maximum value of the nearby flow channel.By applying different loading rates,the influence of loading rate on the average transfer velocity of slow deformation was obtained;the slow deformation wave during seismic migration has similar characteristics to the deformation transfer in the experiment,therefore the research results have reference significance for further studies on the evolution characteristics of slow deformation waves and seismic migration. 展开更多
关键词 Slow deformation Loading rate DIC technology LOCALIZATION
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A Mirror for the Global South
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作者 BUSANI NGCAWENI 《ChinAfrica》 2025年第7期14-15,共2页
A new book urges leaders and intellectuals in the Global South to think for themselves,and to build systems that work for them rather than importing them from elsewhere A s the unipolar world goes through rupture,with... A new book urges leaders and intellectuals in the Global South to think for themselves,and to build systems that work for them rather than importing them from elsewhere A s the unipolar world goes through rupture,with national discontents like slow growth and de-industrialisation,coun-tries are searching for pathways out of the deadlock.This is true of the Global South countries as much as it is for the Global North.In the latter. 展开更多
关键词 INTELLECTUALS build systems work slow growth systems building national discontents global south independent thinking LEADERS
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Spatiotemporal evolution of long-term slow slip events at the Hikurangi subduction zone,New Zealand(2021-2023):Implications for seismic activity
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作者 Li Yan Yanling Sun +2 位作者 Meng Li Ahmed El-Mowafy Tieding Lu 《Geodesy and Geodynamics》 2025年第4期369-377,共9页
Various slow slip events(SSEs)with distinct characteristics have been detected globally,particularly in regions with dense Global Navigation Satellite Systems(GNSS)networks.In the Hikurangi subduction zone of New Zeal... Various slow slip events(SSEs)with distinct characteristics have been detected globally,particularly in regions with dense Global Navigation Satellite Systems(GNSS)networks.In the Hikurangi subduction zone of New Zealand,SSEs frequently occur alongside seismic activity,especially in the Manawatu and Kapiti regions.This study analyzes the 2021-2023 Kapiti-Manawatu long-term SSE using daily displacement data(2019-2023)from 53 GPS stations.The network inversion filter(NIF)method is applied to extract slow slip signals,revealing spatial migration with alternating slip between Kapiti and Manawatu,characterized by distinct phases of acceleration and deceleration.Manawatu exhibits higher slip rates,exceeding 4 cm/month,with greater cumulative slip and surface displacement than Kapiti.A moderate temporal correlation(coefficient 0.59)between seismic activity in the region and slip acceleration in Manawatu suggests that seismic events may contribute to the slip,while no significant correlation is observed in Kapiti. 展开更多
关键词 Long-term slow slip events Spatiotemporal evolution Seismic activity GNSS New Zealand
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Motoric cognitive risk syndrome:A review of fall risk assessment and management strategies
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作者 Hao Peng Na Yao +4 位作者 Yan-Ping Song Li Huang Hong-Bo Chen Yang Jiang Qi-Gang Chen 《World Journal of Psychiatry》 2025年第4期14-25,共12页
The aging global population is driving an increase in dementia,making the early identification of at-risk individuals crucial.Studies have shown that elderly people often exhibit a slowing gait before dementia diagnos... The aging global population is driving an increase in dementia,making the early identification of at-risk individuals crucial.Studies have shown that elderly people often exhibit a slowing gait before dementia diagnosis,which is linked to cognitive decline and predicts dementia risk.With 30%of those over 65 years of age experiencing falls annually,managing fall risk is essential.Motoric cognitive risk syndrome(MCR),characterized by subjective memory impairment and slow gait,is a pre-dementia condition that can identify high-risk individuals without extensive evaluation.The prevalence of MCR varies globally and is associated with an increased risk of falls,disability,and death.Early screening and intervention for MCR can delay dementia and improve fall regulation,offering a new perspective on elderly health management.This review synthesizes the current understanding of MCR-related falls,evaluates risk assessment methods,and discusses health strategies to provide a theoretical basis for fall prevention in community-dwelling older adults. 展开更多
关键词 Motoric cognitive risk syndrome DEMENTIA Gait slowing Fall risk Early intervention
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A coherent generator group identification algorithm under extreme conditions
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作者 Yizhe Zhu Yulin Chen +3 位作者 Li Li Donglian Qi Jinhua Huang Xudong Song 《Global Energy Interconnection》 2025年第1期92-105,共14页
With the rapid development of large-scale regional interconnected power grids,the risk of cascading failures under extreme condi-tions,such as natural disasters and military strikes,has increased significantly.To enha... With the rapid development of large-scale regional interconnected power grids,the risk of cascading failures under extreme condi-tions,such as natural disasters and military strikes,has increased significantly.To enhance the response capability of power systems to extreme events,this study focuses on a method for generator coherency detection.To overcome the shortcomings of the traditional slow coherency method,this paper introduces a novel coherent group identification algorithm based on the theory of nonlinear dynam-ical systems.By analyzing the changing trend of the Euclidean norm of the state variable derivatives in the reduced system,the algorithm can accurately identify the magnitude of the disturbances.Based on the slow coherency methods,the algorithm can correctly recognize coherent generator groups by analyzing system characteristics under varying disturbance magnitudes.This improvement enhances the applicability and accuracy of the coherency detection algorithm under extreme conditions,providing support for emergency control and protection in the power system.Simulations and comparison analyses on IEEE 39-bus system are conducted to validate the accuracy and superiority of the proposed coherent generator group identification method under extreme conditions. 展开更多
关键词 Generator grouping Slow coherency method Nonlinear dynamical system BCU method Energy function
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Randomized autoregressive dynamic slow feature analysis method for industrial process fault monitoring
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作者 Qingmin Xu Peng Li +3 位作者 Aimin Miao Xun Lang Hancheng Wang Chuangyan Yang 《Chinese Journal of Chemical Engineering》 2025年第7期298-314,共17页
Kernel-based slow feature analysis(SFA)methods have been successfully applied in the industrial process fault detection field.However,kernel-based SFA methods have high computational complexity as dealing with nonline... Kernel-based slow feature analysis(SFA)methods have been successfully applied in the industrial process fault detection field.However,kernel-based SFA methods have high computational complexity as dealing with nonlinearity,leading to delays in detecting time-varying data features.Additionally,the uncertain kernel function and kernel parameters limit the ability of the extracted features to express process characteristics,resulting in poor fault detection performance.To alleviate the above problems,a novel randomized auto-regressive dynamic slow feature analysis(RRDSFA)method is proposed to simultaneously monitor the operating point deviations and process dynamic faults,enabling real-time monitoring of data features in industrial processes.Firstly,the proposed Random Fourier mappingbased method achieves more effective nonlinear transformation,contrasting with the current kernelbased RDSFA algorithm that may lead to significant computational complexity.Secondly,a randomized RDSFA model is developed to extract nonlinear dynamic slow features.Furthermore,a Bayesian inference-based overall fault monitoring model including all RRDSFA sub-models is developed to overcome the randomness of random Fourier mapping.Finally,the superiority and effectiveness of the proposed monitoring method are demonstrated through a numerical case and a simulation of continuous stirred tank reactor. 展开更多
关键词 Slow feature analysis Random Fourier mapping Bayesian Inference Autoregressive dynamic modeling CSTR Fault detection
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Unveiling Xuanshen decoction:A novel approach to combat slow transit constipation
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作者 Xing-Lin Zeng Lian-Jun Zhu +2 位作者 Yu Zhang Xiang-Dong Yang Yu-Jun Zhu 《World Journal of Gastroenterology》 2025年第30期126-143,共18页
BACKGROUND Xuanshen decoction(XSD)is a traditional Chinese medicine formulation that is often applied in treating slow transit constipation(STC).However,its specific therapeutic mechanism remains to be characterized.A... BACKGROUND Xuanshen decoction(XSD)is a traditional Chinese medicine formulation that is often applied in treating slow transit constipation(STC).However,its specific therapeutic mechanism remains to be characterized.AIM To investigate the mechanism of XSD for STC,we combined network pharmacology prediction,molecular docking analysis,and in vivo studies.METHODS The therapeutic effects of XSD on loperamide-induced STC in rats were assessed through 24-hour fecal number,fecal moisture content,and intestinal propelling rate.Hematoxylin–eosin and Alcian blue/periodic acid-Schiff staining were applied to analyze colonic mucosa for histopathological presentation and mucin production.Next,the mechanism of action of XSD for STC was elucidated through network pharmacology and molecular docking analyses,and the findings were validated by the animal experiments.RESULTS XSD significantly alleviated the symptoms of STC in rats.Relative to the STC rats,in the medium-dose XSD and high-dose XSD rats,stem cell factor,C-kit,phosphophosphoinositide 3-kinase/phosphoinositide 3-kinase,phospho-protein kinase B/protein kinase B,catalase,and superoxide dismutase were substantially upregulated(P<0.01);nuclear factor erythroid 2-related factor 2(nuclear/cytoplasmic)and B-cell lymphoma 2(Bcl-2)were increased(P<0.05),while cleaved caspase-3,Bcl-2-associated X protein(Bax)/Bcl-2,and malondialdehyde were significantly reduced(P<0.01).Heme oxygenase-1 and glutathione peroxidase in the high-dose XSD group were significantly increased(P<0.01),and Bax was statistically lowered(P<0.01);glutathione peroxidase in the medium-dose XSD group was increased(P<0.05),while Bax was reduced(P<0.05).CONCLUSION XSD may inhibit oxidative-stress-induced apoptosis in interstitial cells of Cajal by stimulating the phosphoinositide 3-kinase/protein kinase B/nuclear factor erythroid 2-related factor 2 pathway,thereby effectively treating STC. 展开更多
关键词 Slow transit constipation Oxidative stress Network pharmacology Experimental verification Molecular docking
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From racing driver to barefoot world traveler
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作者 孙启禄 《疯狂英语(新悦读)》 2025年第7期28-31,77,共5页
Axel Pons,once a Moto2 World Championship competitor,made a big lifestyle change several years ago when he decided to travel the world barefoot.He's the son of Sito Pons,who has been a MotoGP winner twice.At the s... Axel Pons,once a Moto2 World Championship competitor,made a big lifestyle change several years ago when he decided to travel the world barefoot.He's the son of Sito Pons,who has been a MotoGP winner twice.At the start of his motorcycle-racing career,there were high expectations and a lot of pressure on him.In the Moto2 World Championship,he had some good results,with a 16th-place finish in 2016 being his best.But then he took a break from racing and tried fashion modeling.In 2019,he said he wanted to slow down and leave his past behind.But no one expected the kind of change that was coming. 展开更多
关键词 slow down Axel Pons barefoot travel racing driver Moto world championship lifestyle change fashion modeling fashion modelingin
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CoⅡsingle-ion magnet and its multi-dimensional aggregations:Influence of the structural rigidity on magnetic relaxation process
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作者 Zhao-Bo Hu Ling-Ao Gui +9 位作者 Long-He Li Tong-Tong Xiao Adam THand Pagnareach Tin Mykhaylo Ozerov Yan Peng Zhongwen Ouyang Zhenxing Wang Zi-Ling Xue You Song 《Chinese Chemical Letters》 2025年第2期518-522,共5页
Two CoⅡ-based complexes,{[Co(dps)_(2)(N_(3))_(2)]·H_(2)O}_n(1)and[Co(dps)_(2)(N_(3))_(2)]_n(2),show a 1D chain and a 3D network,respectively.The central CoⅡions in the complexes have the same coordination envir... Two CoⅡ-based complexes,{[Co(dps)_(2)(N_(3))_(2)]·H_(2)O}_n(1)and[Co(dps)_(2)(N_(3))_(2)]_n(2),show a 1D chain and a 3D network,respectively.The central CoⅡions in the complexes have the same coordination environment with the[Co(dps)_(4)(N_(3))_(2)]unit.Although the differences in crystal parameters are nearly negligible,their magnetic properties are very different.AC susceptibility data show that 1 behaves as a typical field-induced single-ion magnet(SIM)with the out-of-phase(χ_(M)”)signals,while 2 shows ac signals ofχ_(M)”without peaks even under applied dc filed within our measurement window.Far-IR magneto-spectra(FIRMS)show strong spin-phonon couplings at 0 T in 2,likely making the magnetic relaxation in 2 fast,while the couplings are negligible in 1.Small spin-phonon coupling in 1 likely leads to slower magnetic relaxation,making 1 a SIM.The difference in the properties is due to the structural rigidity of 2 in its 3D network,leading to stronger spin-phonon coupling.Combined high-field EPR(HF-EPR)and FIRMS studies give spin-Hamiltonian parameters,including D=64.0(9)cm^(-1),|E|=15.7(2)cm^(-1)for 1 and D=80.0(2)cm^(-1),|E|=19.0(1)cm^(-1)for 2. 展开更多
关键词 Spin-phonon coupling Slow magnetic relaxation Structural rigidity CoII compounds Far-IR magneto-spectra
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Modification of slow relaxation of magnetization behavior via substituent change on two neutral mononuclear dysprosium(Ⅲ) single-molecule magnets
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作者 Leilei Li Libo Zhang +4 位作者 Anzhi Huang Shuang Liu Wenzhen Wang Hongjiang Yu Yiquan Zhang 《Journal of Rare Earths》 2025年第9期1901-1908,共8页
Structural fine-tuning is of significant importance to enhance the magnetic anisotropy and elucidate the magneto-structural relationship for single molecule magnets(SMMs).For this purpose,two mononuclear Dy^(3+) SMMs:... Structural fine-tuning is of significant importance to enhance the magnetic anisotropy and elucidate the magneto-structural relationship for single molecule magnets(SMMs).For this purpose,two mononuclear Dy^(3+) SMMs:[Dy{HB(pz)3}2(Sal)](1) and [Dy{HB(pz)_(3)}_(2)(MeO-Sal)](2),where HB(pz)_(3)^(-)represents hydro tris(pyrazolyl)borate,Sal denotes salicyiaidehyde and MeO-Sal stands for 5-methoxysalicylaldehyde,were designed and synthesized.Single crystal X-ray diffraction tests show that the two SMMs have very similar eight-coordinated molecule structures,although the introducing of-MeO substituent on salicyiaidehyde ligand induces the changes on the molecule packing mode and the space group.Both the two SMMs have a Dy-O_(aryloxidebond) that is significantly shorter than other Dy-O/N bonds,which defines the orientation of main anisotropy axis of the ground Kramers doublets and engenders the slow relaxation of the magnetization behavior,as evidenced by the magnetic susceptibility and the ab initio calculation.Though with an electron-donating substituent on the axial Sal ligand in 2,the collective magnetic anisotropy is not enhanced and the corresponding magneto-structural relationship is discussed based on the experimental and theoretical calculation results.In addition,as neutral molecules,1 and 2 are soluble in several common organic solvents,like CH_(2)Cl_(2),CHCl_(3),THF and so on. 展开更多
关键词 DYSPROSIUM Rare earths Single molecule magnet Magnetic property Magnetic anisotropy Slow magnetic relaxation
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Plasmon-induced transparency based on a molybdenum disulfide film terahertz metasurface for sensing applications
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作者 Wang Yilin Chen Fang +1 位作者 Yang Wenxing Yi Zao 《Communications in Theoretical Physics》 2025年第9期97-107,共11页
In this study,we proposed a bifunctional sensor of high sensitivity and slow light based on monolayer Mo S/TOPAS2structure in the terahertz range.The proposed metamaterial is formed by a structured unit matrix that co... In this study,we proposed a bifunctional sensor of high sensitivity and slow light based on monolayer Mo S/TOPAS2structure in the terahertz range.The proposed metamaterial is formed by a structured unit matrix that combines square and cross shapes made of MoS2and TOPAS.The plasmon-induced transparency(PIT)spectra appeared under the excitation of a transverse magnetic(TM)-polarization wave,the proposed PIT effect is originated from the near-field coupling of two bright modes.The Lorentzian mode theory spectrum describes the destructive interference between the two bright modes,and the fitted results are consistent with the FiniteDifference Time-Domain(FDTD)simulation results.Furthermore,the effect of geometrical sizes,like coupling distance,structure size,and intersection angle between square and cross shape on the PIT window is analyzed,along with the effects of carrier concentration in Mo S2.A figure of merit of-1.10 RIU1is obtained.The slow light performance of the proposed Mo S2-based metamaterial is investigated,a maximum time delay of 0.52 ps is obtained and the delay band width product(DBP)is 0.76.It is more efficient to store and transmit the information over signal channels.Therefore,the proposed Mo S2-based metamaterial can be used in electromagnetically induced transparency applications,such as sensors,optical memory devices,and flexible terahertz functional devices. 展开更多
关键词 plasmon-induced transparency high sensitivity slow light
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A fluorescence-enhanced inverse opal sensing film for multi-sources detection of formaldehyde
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作者 Xiaokang Lu Bo Han +6 位作者 Deyilei Wei Mingzhu Chu Haojie Ma Ran Li Xueyan Hou Yuqi Zhang Jijiang Wang 《Food Science and Human Wellness》 2025年第5期1818-1826,共9页
The SiO_(2) inverse opal photonic crystals(PC)with a three-dimensional macroporous structure were fabricated by the sacrificial template method,followed by infiltration of a pyrene derivative,1-(pyren-8-yl)but-3-en-1-... The SiO_(2) inverse opal photonic crystals(PC)with a three-dimensional macroporous structure were fabricated by the sacrificial template method,followed by infiltration of a pyrene derivative,1-(pyren-8-yl)but-3-en-1-amine(PEA),to achieve a formaldehyde(FA)-sensitive and fluorescence-enhanced sensing film.Utilizing the specific Aza-Cope rearrangement reaction of allylamine of PEA and FA to generate a strong fluorescent product emitted at approximately 480 nm,we chose a PC whose blue band edge of stopband overlapped with the fluorescence emission wavelength.In virtue of the fluorescence enhancement property derived from slow photon effect of PC,FA was detected highly selectively and sensitively.The limit of detection(LoD)was calculated to be 1.38 nmol/L.Furthermore,the fast detection of FA(within 1 min)is realized due to the interconnected three-dimensional macroporous structure of the inverse opal PC and its high specific surface area.The prepared sensing film can be used for the detection of FA in air,aquatic products and living cells.The very close FA content in indoor air to the result from FA detector,the recovery rate of 101.5%for detecting FA in aquatic products and fast fluorescence imaging in 2 min for living cells demonstrate the reliability and accuracy of our method in practical applications. 展开更多
关键词 Inverse opal photonic crystals Slow photon effect Fluorescence enhancement Multi-sources detection FORMALDEHYDE
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