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Study on the destabilizing damage precursors of cemented tailings backfill based on critical slowing down theory combined with multiple denoising algorithms under consideration of initial defect conditions
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作者 ZHAO Kang ZHONG Jun-cheng +3 位作者 YAN Ya-jing LIU Yang WEN Dao-tan XIAO Wei-ling 《Journal of Central South University》 2026年第1期375-399,共25页
The cemented tailings backfill(CTB)with initial defects is more prone to destabilization damage under the influence of various unfavorable factors during the mining process.In order to investigate its influence on the... The cemented tailings backfill(CTB)with initial defects is more prone to destabilization damage under the influence of various unfavorable factors during the mining process.In order to investigate its influence on the stability of underground mining engineering,this paper simulates the generation of different degrees of initial defects inside the CTB by adding different contents of air-entraining agent(AEA),investigates the acoustic emission RA/AF eigenvalues of CTB with different contents of AEA under uniaxial compression,and adopts various denoising algorithms(e.g.,moving average smoothing,median filtering,and outlier detection)to improve the accuracy of the data.The variance and autocorrelation coefficients of RA/AF parameters were analyzed in conjunction with the critical slowing down(CSD)theory.The results show that the acoustic emission RA/AF values can be used to characterize the progressive damage evolution of CTB.The denoising algorithm processed the AE signals to reduce the effects of extraneous noise and anomalous spikes.Changes in the variance curves provide clear precursor information,while abrupt changes in the autocorrelation coefficient can be used as an auxiliary localization warning signal.The phenomenon of dramatic increase in the variance and autocorrelation coefficient curves during the compression-tightening stage,which is influenced by the initial defects,can lead to false warnings.As the initial defects of the CTB increase,its instability precursor time and instability time are prolonged,the peak stress decreases,and the time difference between the CTB and the instability damage is smaller.The results provide a new method for real-time monitoring and early warning of CTB instability damage. 展开更多
关键词 initial defects cemented tailings backfill critical slowing down acoustic emission RA/AF values denoising algorithms
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Prediction and critical transition mechanism for granite fracture:Insights from critical slowing down theory 被引量:3
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作者 WANG Chun-lai ZHOU Bao-kun +6 位作者 LI Chang-feng WEN Zhi-jie BAI Zhi-an ZHU Chao-yang SUN Liang XUE Xu-hui CAO Peng 《Journal of Central South University》 SCIE EI CAS CSCD 2024年第8期2748-2764,共17页
Rock fracture warning is one of the significant challenges in rock mechanics.Many true triaxial and synchronous acoustic emission(AE)tests were conducted on granite samples.The investigation focused on the characteris... Rock fracture warning is one of the significant challenges in rock mechanics.Many true triaxial and synchronous acoustic emission(AE)tests were conducted on granite samples.The investigation focused on the characteristics of AE signals preceding granite fracture,based on the critical slowing down(CSD)theory.The granite undergoes a transition from the stable phase to the fracture phase and exhibits a clear CSD phenomenon,characterized by a pronounced increase in variance and autocorrelation coefficient.The variance mutation points were found to be more identifiable and suitable as the primary criterion for predicting precursor information related to granite fracture,compared to the autocorrelation coefficient.It is noteworthy to emphasize that the CSD factor holds greater potential in elucidating the underlying mechanisms responsible for the critical transition of granite fracture,in comparison to the AE timing parameters.Furthermore,a novel multi-parameter collaborative prediction method for rock fracture was developed by comprehensively analyzing predictive information,including abnormal variation modes and the CSD factor of AE characteristic parameters.This method enhances the understanding and prediction of rock fracture-related geohazards. 展开更多
关键词 GRANITE triaxial compression acoustic emission rock fracture critical slowing down theory
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Modeling of beam ions loss and slowing down with Coulomb collisions in EAST
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作者 Yifeng Zheng Jianyuan Xiao +4 位作者 Baolong Hao Liqing Xu Yanpeng Wang Jiangshan Zheng Ge Zhuang 《Chinese Physics B》 SCIE EI CAS CSCD 2022年第7期389-403,共15页
This paper uses the implicit Monte–Carlo full-orbit-following parallel program ISSDE to calculate the prompt loss and slowing down process of neutral beam injection(NBI)-generated fast ions due to Coulomb collisions ... This paper uses the implicit Monte–Carlo full-orbit-following parallel program ISSDE to calculate the prompt loss and slowing down process of neutral beam injection(NBI)-generated fast ions due to Coulomb collisions in the equilibrium configuration of Experimental Advanced Superconducting Tokamak(EAST).This program is based on the weak equivalence of the Fokker–Planck equation under Rosenbluth Mac Donald Judd(RMJ)potential and Stratonovich stochastic differential equation(SDE).The prompt loss with the LCFS boundary and the first wall(FW)boundary of the two co-current neutral injection beams are studied.Simulation results indicate that the loss behavior of fast ions using the FW boundary is very different from that of the LCFS boundary,especially for fast ions with a large gyration radius.According to our calculations,about 5.11%of fast ions generated by perpendicular injection drift out of the LCFS and then return inside the LCFS to be captured by the magnetic field.The prompt loss ratio of fast ions and the ratio of orbital types depend on the initial distribution of fast ions in the Pζ–Λspace.Under the effect of Coulomb collisions,the pitch-angle scattering and stochastic diffusion happens,which will cause more fast ion loss.For short time scales,among the particles lost due to collisions,the fraction of banana ions reaches 92.31%in the perpendicular beam and 58.65%in the tangential beam when the fraction of banana ions in the tangential beam is 3.4%of the total ions,which means that the effect of Coulomb collisions on banana fast ions is more significant.For long time scales,the additional fast ion loss caused by Coulomb collisions of tangential and perpendicular beams accounted for 16.21%and 25.05%of the total particles,respectively.We have also investigated the slowing down process of NBI fast ions. 展开更多
关键词 NBI fast ion loss slowing down process EAST Coulomb collisions
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Empirical six-dimensional framework for slowing and reversing ageing using modern science and ancient wisdom
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作者 Asoka Nimal Jinadasa 《Life Research》 2019年第3期106-112,共7页
There are numerous published theories that cover the different biological processes relating to ageing. No one seems to have integrated such complex and seemingly unrelated information into a holistic framework that e... There are numerous published theories that cover the different biological processes relating to ageing. No one seems to have integrated such complex and seemingly unrelated information into a holistic framework that explains in simple terms the key aspects of ageing and provides a set of daily practices for staying young and healthy. An atiempt is made here to select a 6-dimensional framework symbolized by heart, mind, passion, focus, body and health, and correlate it to the mental, emotional, physical and health aspects of ageing. Based on grounded theory, this paper empirically correlates 30 practical methods that can be used to develop all six dimensions, with 18 key factors that were found to infl uence ageing: Neurogenesis;Epigenetic reprogramming;Removing dying cells;Mitochondria resuscitation;Calorie restriction;Plant-based diet;Regular physical activity;Chi Kung (Qigong);Overcoming anxiety, depression and stress;Positive mind-set;Some worrying;Vitamins and minerals;L-Theanine;Omega-3 and healthy fats;Coenzyme Q-10;Pyrroloquinoline quinone;Nitric oxide;Choline. In this study, 26 references were used to establish that all 18 of these seemingly unrelated key anti-ageing factors can be developed using 30 daily practices derived from the 6-dimensional framework. These simple daily prac-tices can help people of all ages to stay young and healthy, and help older people who are living alone to self-improve their quality of life without needing anyone to look atier them. Since many anti-ageing drugs seem to be ineffective, this study provides a holistic new research direction for using modern science and ancient human energy practices combined with wholesome nutrition to slow ageing and age-related illnesses. 展开更多
关键词 slowing ageing Reversing ageing AGE-RELATED illnesses Prolonging YOUTH Improving health Alzheimer's
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Study on Critical Slowing Down Phenomenon before the Two Medium-strong Earthquakes in Xinjiang
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作者 Gao Lijuan Yang Youling +1 位作者 Liu Jianming Zhu Chengying 《Earthquake Research in China》 CSCD 2015年第3期394-403,共10页
We study the critical slowing down phenomenon in deformation and groundwater observations before the Nilka-Gongliu MS6. 0 earthquake on November 1, 2011 and Xinyuan-Hejing M S6. 6 earthquake on June 30,2012. Firstly,w... We study the critical slowing down phenomenon in deformation and groundwater observations before the Nilka-Gongliu MS6. 0 earthquake on November 1, 2011 and Xinyuan-Hejing M S6. 6 earthquake on June 30,2012. Firstly,we remove the annual variation and tendency change of basic data by means of wavelet transform analysis.Secondly,we calculate the autocorrelation coefficients and variance of the critical slowing down phenomenon. Lastly,we try to verify the critical slowing down phenomenon before an earthquake. The result indicates that there was obvious critical slowing down of the records at different stations before earthquakes. 展开更多
关键词 Critical slowing down Autocorrelation coefficient Variance Earthquakeprediction
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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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Just How Much Is the Economy Slowing
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作者 Kathleen Madigan 赵忠德 《语言教育》 1999年第1期66-67,共2页
Is the American economy slowing or growing?WallStreet and Corporate America have different views.FederalReserve Chairman Alan Greespan told Congress that it looksas if the economy is slowing.As real retail sales。
关键词 Just How Much Is the Economy slowing
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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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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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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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Strain rate of Boso slow slip events related to seismic activity after 2011 using GNSS data
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作者 Li Yan Xinzheng Xiao +2 位作者 Tieding Lu Ahmed El-Mowafy Meng Li 《Geodesy and Geodynamics》 2025年第6期644-655,共12页
The March 11,2011,MW9.0 Tohoku-Oki earthquake,in Japan,caused rapid strain release near the epicenter,while the Boso Peninsula,located farther away,experienced stress redistribution,leading to changes in the recurrenc... The March 11,2011,MW9.0 Tohoku-Oki earthquake,in Japan,caused rapid strain release near the epicenter,while the Boso Peninsula,located farther away,experienced stress redistribution,leading to changes in the recurrence interval of slow slip events(SSEs)and regional strain.This study focuses on three detected post-2011 Boso SSEs,utilizing a segmented model displacement time series measured by Global Navigation Satellite System(GNSS)to calculate velocity and strain rate fields for eight periods before,during,and after the SSEs.Results show that the 2011 earthquake and the three SSEs significantly alter the velocity field in the Boso region,with SSE velocities predominantly oriented southeast,reaching maximum values of 26.9 cm/a,10.6 cm/a,and 38.5 cm/adnearly opposite to non-SSE periods.After the third SSE,the velocity field nearly returns to its pre-earthquake state,with a maximum of 1.8 cm/a.The maximum shear strain rates during the three SSEs are 25.88×10^(-7) a^(-1),11.38×10^(-7) a^(-1),and 29.02×10^(-7) a^(-1)(i.e.,per annum),significantly higher than those during non-slow slip periods,with principal strain rates following a similar pattern.The spatial distribution of strain rates during the SSEs indicates greater deformation compared to the non-slip periods,dominated by northwest-southeast extension and southwest-northeast compression.Spatiotemporal analysis reveals a strong correlation between seismic frequency and strain rate during the SSEs,with time correlation coefficients of 0.85,0.88,and 0.9.Although larger accumulated strain results in stronger strain release during the latter two SSEs,not all strain is fully released,suggesting that earthquake swarms accompanying the SSEs may contribute to the partial release of unreleased strain.This study,through the analysis of GNSS data,evaluates the spatiotemporal distribution of strain fields during periodic SSEs,contributing to further research on strain accumulation and release,and aiding in the analysis of this regional seismic activity. 展开更多
关键词 Strain rates slow slip events Seismic activity GNSS VELOCITY
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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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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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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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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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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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Intestinal microbiota composition and bile salt hydrolase activity in fast and slow growing broiler chickens:implications for growth performance and production efficiency
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作者 Hye Won Kim Na Kyung Kim +6 位作者 Patricia G.Wolf Kristoffer Brandvold Joshua M.Rehberger Tom G.Rehberger Ryan N.Dilger Alexandra H.Smith Roderick I.Mackie 《Journal of Animal Science and Biotechnology》 2025年第6期2751-2767,共17页
Background Body weight is an important indicator of the overall health and production efficiency in broiler chickens.In broiler houses,body weight of chicks is variable despite the same genetics,hatching and feeding p... Background Body weight is an important indicator of the overall health and production efficiency in broiler chickens.In broiler houses,body weight of chicks is variable despite the same genetics,hatching and feeding practices within a production system.The objective of this study was to investigate the intestinal microbiota and bile salt hydrolase(BSH)activity in slow and fast growing broiler chickens,which belonged to the 10th and 90th percentile body weight groups,respectively.Methods A total of 300 Ross 308 broiler chickens(100 per cohort from three independent cohorts)were selected and mucosal samples from the jejunum,ileum,and cecum were collected at day of arrival,11 and 25(n=450).Then,bacterial counts,16S rRNA amplicon sequencing,species specific real-time qPCR,as well as BSH activity were analyzed.Results Results of bacterial counts showed no significant difference between slow and fast growing cohorts(P>0.05),but they tended to be higher in the slow growing chickens in all measured bacterial groups in cecum.The 16S rRNA amplicon sequencing revealed higher relative abundance of E.coli-Shigella(71.3%−79.8%)at day of arrival,while the most abundant microorganisms at d 25 was Candidatus Arthromitus(slow:44.5%;fast:27.4%)in small intestine.qPCR results indicated significant differences in bacterial populations between the slow and fast growing chickens,especially higher total bacteria,Enterococcus,and Clostridium cluster I in the slow growing chickens at d 25.BSH activity was higher in the slow growing chickens than the fast growing chickens[slow:0.476ΔOD/protein(μg/mL);fast:0.258ΔOD/protein(μg/mL);P<0.0001],and correlation analysis highlighted associations between BSH activity,body weight,feed intake,body weight gain,and bacterial counts.Conclusions We postulate that high total bacteria and Enterococcus abundance are associated with high BSH activity,impacting low feed intake and body weight gain,ultimately resulting in separation into slow and fast growing birds.The findings of this study contribute to understanding the relationship between gut microbiota,BSH activity,and host physiology in broiler chickens,with potential implications for poultry production. 展开更多
关键词 Bile salt hydrolase activity Broiler chickens Fast growing Gut microbiota slow growing
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Impact of Heavy Slow Resistance vs. Convectional Exercise in Lateral Epicondylitis--A Pilot Study
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作者 S.M.Divya Mary Jibi Paul +1 位作者 V.Hema Suresh P.Senthil 《Health Care Science》 2025年第2期71-81,共11页
Background:The extensor carpi radial muscle may become imbalanced compared to other muscles in the upper arm and can disrupt the overall muscle balance in the upper limb.This muscular imbalance may then cause inflamma... Background:The extensor carpi radial muscle may become imbalanced compared to other muscles in the upper arm and can disrupt the overall muscle balance in the upper limb.This muscular imbalance may then cause inflammation or irritation in the tendon.Regular physical activity is rarely used as the only treatment for lowering limb edema.Heavy slow resistance(HSR)training is effective compared to regular exercises.HSR affects functional abilities and physical refinement differently from conventional workouts.This study evaluated the effects of HSR and conventional exercise(CE)on subjects aged 45–65 years with unilateral elbow pain on,in Chennai city.Methods:Patient received conservative care in the Physiotherapy Department from January 2022 to April 2022.This study compares the pre-and posttypes.Tennis Elbow Evaluation(Patient-Rated Tennis Elbow Evaluation,PRTEE)questionnaires,a patient-specific functional scale,and grip strength tests were used in the study.Results from the study's treatment HSR group and treatment CE group are contrasted.Results:After 12 weeks of therapy,investigators reassessed grip strength,PRTEE scores,and functional scale responses.In the posttest results of the Patient-Rated Tennis Elbow Evaluation survey,there is a statistically significant difference between Group HSR and Group CE(p<0.001).The posttest outcomes from the patient-specific activity scoring scheme questionnaire revealed a statistically significant disparity between Groups HSR and CE(p<0.001).The mean values for both groups exhibited a noteworthy change,with Team HSR demonstrating higher values in contrast to the control treatment.Conclusion:HSR exercise demonstrates superior effectiveness over CEs for lateral epicondylitis(LE)management,emphasizing its significance in treatment. 展开更多
关键词 activities of daily living heavy slow resistance lateral epicondylitis movement component task specific training traditional exercise
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Coulomb stressing rate changes and seismicity dynamics associated with slow slip events in south-central Alaska
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作者 ShanShan Li XingLei Li Bing Xu 《Earth and Planetary Physics》 2025年第2期289-308,共20页
Two long-term slow slip events(SSEs) in Lower Cook Inlet, Alaska, were identified by Li SS et al.(2016). The earlier SSE lasted at least 9 years with M_(w) ~7.8 and had an average slip rate of ~82 mm/year. The latter ... Two long-term slow slip events(SSEs) in Lower Cook Inlet, Alaska, were identified by Li SS et al.(2016). The earlier SSE lasted at least 9 years with M_(w) ~7.8 and had an average slip rate of ~82 mm/year. The latter SSE, occurring in a similar area, lasted approximately 2 years with M_(w) ~7.2 and an average slip rate of ~91 mm/year. To test whether these SSEs triggered earthquakes near the slow slip area, we calculated the Coulomb stressing rate changes on receiver faults by using two fault geometry definitions: nodal planes of focal mechanism solutions of past earthquakes, and optimally oriented fault planes. Regions in the shallow slab(30–60 km) that experienced a significant increase in the Coulomb stressing rate due to slip by the SSEs showed an increase in seismicity rates during SSE periods. No correlation was found in the volumes that underwent a significant increase in the Coulomb stressing rate during the SSE within the crust and the intermediate slab. We modeled variations in seismicity rates by using a combination of the Coulomb stress transfer model and the framework of rate-and-state friction. Our model indicated that the SSEs increased the Coulomb stress changes on adjacent faults,thereby increasing the seismicity rates even though the ratio of the SSE stressing rate to the background stressing rate was small. Each long-term SSE in Alaska brought the megathrust updip of the SSE areas closer to failure by up to 0.1–0.15 MPa. The volumes of significant Coulomb stress changes caused by the Upper and Lower Cook Inlet SSEs did not overlap. 展开更多
关键词 slow slip events Coulomb stressing rate change seismicity rate change receiver fault rate–state stress transfer model seismogenic zone megathrust failure
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Research on resonant ring-modified photonic crystal line-defect slow-light waveguide
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作者 LIU Qianzhen MA Chengju LI Yan 《Optoelectronics Letters》 2025年第7期419-426,共8页
This paper presents a photonic crystal(PhC)line-defect slow-light waveguide modified by resonant rings.We introduce resonant rings into the line defect,constructing a slow-light waveguide with high normalized delay ba... This paper presents a photonic crystal(PhC)line-defect slow-light waveguide modified by resonant rings.We introduce resonant rings into the line defect,constructing a slow-light waveguide with high normalized delay bandwidth product(NDBP)and low group velocity dispersion(GVD).We simulate,analyze,and optimize the structural parameters of this slow-light waveguide using the finite difference time domain(FDTD)method,theoretically achieving a maximum group index of 3.7,maximum bandwidth of 15.6 nm,and maximum NDBP of 0.4416 for slow-light effect.The resonant ring-modified PhC slow-light waveguide designed in this paper exhibits GVD lower than the order of 10^(−20)s^(2)/m over a normalized frequency range from 0.3554 to 0.4175.This study is expected to provide theoretical references for the study of slow-light buffering devices based on PhCs with high NDBP values. 展开更多
关键词 finite difference time domain fdtd methodtheoretically line defect slow light waveguide normalized delay bandwidth product resonant rings low group velocity dispersion gvd we resonant ringswe maximum ndb photonic crystal
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