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Giant Drag Fluctuations in Graphene-Based Electronic Double-Layer Systems
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作者 Chi Zhang Lijun Zhu +1 位作者 Lin Li Changgan Zeng 《Chinese Physics Letters》 2025年第11期271-292,共22页
Recent advances in two-dimensional layered systems have greatly enriched electronic transport studies, particularly in inter-layer Coulomb drag research. Here, systematic transport measurements were conducted in graph... Recent advances in two-dimensional layered systems have greatly enriched electronic transport studies, particularly in inter-layer Coulomb drag research. Here, systematic transport measurements were conducted in graphene-based electronic double-layer structures, revealing giant yet reproducible drag fluctuations at cryogenic temperatures. These fluctuations' characteristics, including amplitude and peak/valley spacing, are mainly determined by the drag layer's carrier dynamics rather than the drive layer's, resulting in violation of the Onsager reciprocity relation. Notably, the drag fluctuations remain observable up to 35 K, far exceeding universal conductance fluctuations within individual layers. This suggests enhanced phase coherence in inter-layer drag compared to single-layer transport, as further confirmed by quantitative analysis of auto-correlation fields of fluctuations under magnetic fields. Our findings provide new insights into quantum interference effects and their interplay with Coulomb interactions in solids. The observations of significant drag fluctuations could potentially help address chaotic signals between nearby components in nanoscale devices. 展开更多
关键词 giant drag fluctuations electronic transport studies graphene based electronic double layer systems drive layers drag fluctuations drag layers carrier dynamics cryogenic temperatures systematic transport measurements
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Improved reference-frame-independent quantum key distribution with intensity fluctuations
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作者 Zi-Qi Chen Hao-Bing Sun +1 位作者 Ming-Shuo Sun Qin Wang 《Chinese Physics B》 2025年第2期48-52,共5页
Reference-frame-independent quantum key distribution(RFI-QKD)can avoid real-time calibration operation of reference frames and improve the efficiency of the communication process.However,due to imperfections of optica... Reference-frame-independent quantum key distribution(RFI-QKD)can avoid real-time calibration operation of reference frames and improve the efficiency of the communication process.However,due to imperfections of optical devices,there will inevitably exist intensity fluctuations in the source side of the QKD system,which will affect the final secure key rate.To reduce the influence of intensity fluctuations,an improved 3-intensity RFI-QKD scheme is proposed in this paper.After considering statistical fluctuations and implementing global parameter optimization,we conduct corresponding simulation analysis.The results show that our present work can present both higher key rate and a farther transmission distance than the standard method. 展开更多
关键词 quantum key distribution intensity fluctuations decoy-state method
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Acceptance effect on the N_(t)N_(p)/N_(d)^(2)ratio of light nuclei coalescence yields as a probe of nucleon density fluctuations
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作者 An Gu Michael X.Zhang 《Nuclear Science and Techniques》 2025年第3期157-166,共10页
A coalescence model was employed to form deuterons(d),tritons(t),and helium-3(^(3)He)nuclei from a uniformly-distributed volume of protons(p)and neutrons(n).We studied the ratio N_(t)N_(p)/N_(d)^(2)of light nuclei yie... A coalescence model was employed to form deuterons(d),tritons(t),and helium-3(^(3)He)nuclei from a uniformly-distributed volume of protons(p)and neutrons(n).We studied the ratio N_(t)N_(p)/N_(d)^(2)of light nuclei yields as a function of the neutron density fluctuations.We investigated the effect of finite transverse momentum(p_(T))acceptance on the ratio,in particular,the“extrapolation factor”(f)for the ratio as a function of the p_(T)spectral shape and the magnitude of neutron density fluctuations.The nature of f was found to be monotonic in p_(T)spectra“temperature”parameter and neutron density fluctuation magnitude;variations in the latter are relatively small.We also examined f in realistic simulations using the kinematic distributions of protons measured from the heavy-ion collision data.The nature of f was found to be smooth and monotonic as a function of the beam energy.Therefore,we conclude that extrapolation from limited p_(T)ranges does not create,enhance,or reduce the local peak of the N_(t)N_(p)/N_(d)^(2)ratio in the beam energy.Our study provides a necessary benchmark for light nuclei ratios as a probe for nucleon density fluctuations,an important observation in the search for the critical point of nuclear matter. 展开更多
关键词 Heavy-ion collision Critical point Light nuclei coalescence Nucleon density fluctuations
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Mobilization of heavy metals from floodplain sediments of the Yellow River during redox fluctuations
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作者 Fuyu Xie Xiaoqing Li +2 位作者 Qingxiang Yang Ying Meng Fubo Luan 《Journal of Environmental Sciences》 2025年第4期432-439,共8页
The floodplain of the Yellow River is a typical area characterized by redox fluctuations and heavy metal pollution.However,the mobilization behavior of heavy metals in floodplain sediments during redox fluctuations re... The floodplain of the Yellow River is a typical area characterized by redox fluctuations and heavy metal pollution.However,the mobilization behavior of heavy metals in floodplain sediments during redox fluctuations remains poorly understood.In this study,reductive mobilization of Fe and Mn was observed under reducing environments through reduction and dissolution,leading to the subsequent release of adsorbed As.In contrast,the mobilization of U occurred under oxic conditions,as the oxidative state of U(VI)has higher solubility.Furthermore,insignificant effects on the mobilization of Cd,Cu,Pb,and Hg were noticed during redox fluctuations,indicating higher stability of these heavymetals.Additionally,we demonstrated that carbon sources can play a key role in the mobilization of heavy metals in floodplain sediments,amplifying the reductive mobilization of Fe,Mn,As and the oxidative mobilization of U.Our findings contribute to the understanding of the biogeochemical cycling of heavy metal in floodplain sediments of the Yellow River and the factors that control this cycling. 展开更多
关键词 Biogeochemical cycling Redox fluctuation Heavy metal Carbon supplementation The Yellow River
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Fluctuations in the relationship between the Silk Road Pattern and the summer North Atlantic Oscillation
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作者 Yong Liu Zhencai Du 《Atmospheric and Oceanic Science Letters》 2025年第4期35-40,共6页
This study investigated the fluctuations in the relationship between the Silk Road Pattern(SRP)and the boreal summer North Atlantic Oscillation(SNAO).The results indicated that the SRP–SNAO relationship was relativel... This study investigated the fluctuations in the relationship between the Silk Road Pattern(SRP)and the boreal summer North Atlantic Oscillation(SNAO).The results indicated that the SRP–SNAO relationship was relatively weak during 1958–2022,which was primarily due to fluctuations,particularly the reversal in their relationship since the late 1990s.Using wavelet coherence analysis,the authors identified a strong SRP–SNAO linkage on a 4–8-yr timescale,in particular during the mid-1970s to the early/mid-1990s.This strong linkage is mainly attributable to the intensification and eastward movement of the southern part of the SNAO around the mid/late 1970s,which favored the strong connection between the SNAO and the SRP.Additionally,the interdecadal changes of the atmospheric circulations over the North Atlantic and Eurasia around the mid/late 1970s that resembled the circulation anomalies related to the strong SRP–SNAO linkage,may also have provided a favorable background for the strong connection between the two teleconnections.These findings on the fluctuations in the SRP–SNAO linkage may offer important implications for understanding the impact of the SNAO on the SRP and the variability of the SRP. 展开更多
关键词 Silk Road Pattern North Atlantic Oscillation Relationship fluctuation
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Forage Nutrient Fluctuations During the Dry Season:A Case Study of Tropical Grazing Land in East Nusa Tenggara,Indonesia
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作者 Grace Maranatha Putri Pandarangga +1 位作者 Yohanis Umbu Laiya Sobang Fredeicus Dedy Samba 《Research in Ecology》 2025年第4期71-84,共14页
Natural grazing land plays a crucial role in extensive ruminant livestock systems,especially in semi-arid tropical regions such as East Nusa Tenggara(ENT),Indonesia.The availability and quality of forage during the dr... Natural grazing land plays a crucial role in extensive ruminant livestock systems,especially in semi-arid tropical regions such as East Nusa Tenggara(ENT),Indonesia.The availability and quality of forage during the dry season present significant challenges.This study aimed to identify variations in grass species composition and fluctuations in forage nutritional content in natural grazing lands of ENT during the dry season(July–October 2024).Sampling was conducted in four sub-districts:two representing lowland zones and two representing highland zones.In each sub-district,four grazing fields were selected,and ten plots were sampled per grazing field,totaling 160 sampling plots.Species identification and nutrient analysis included crude protein,crude fiber,energy content,and proteinenergy ratio.Statistical analyses using ANOVA and Tukey’s multiple comparison test were performed to evaluate significant differences in nutritional parameters across months and zones.Dominant species identified were Themeda arguens,Heteropogon contortus,Brachiaria decumbens,Ischaemum timorense,Cynodon dactylon,and Pennisetum clandestinum.Results showed significant monthly fluctuations in crude protein and fiber contents(p<0.05),with protein levels decreasing from July(9.31±2.66%)to October(7.53±3.10%).Energy content and protein-energy ratio also varied significantly across the dry season.A monthly shift in dominant grass species composition was observed,influenced by environmental conditions and species adaptability.The protein-energy ratio of forage remained below optimal levels throughout the dry season,potentially limiting livestock productivity.These findings provide important scientific insights for developing climate-resilient feeding strategies and support policy formulation for sustainable tropical livestock farming in semi-arid regions. 展开更多
关键词 Dry Season FORAGE Nutrient fluctuations Tropical Grazing Land East Nusa Tenggara
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Method of Bionic Fish Scale Structure on Pressure Fluctuation Suppression of a Centrifugal Pump
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作者 Xingyu Jia Qixuan Sun +2 位作者 Xuechu Zhao Bing Liu Lei Tan 《哈尔滨工程大学学报(英文版)》 2025年第5期1037-1048,共12页
Centrifugal pumps are extensively employed in ocean engineering,such as ship power systems,water transportation,and mineral exploitation.Pressure fluctuation suppression is essential for the operation stability and se... Centrifugal pumps are extensively employed in ocean engineering,such as ship power systems,water transportation,and mineral exploitation.Pressure fluctuation suppression is essential for the operation stability and service life of the centrifugal pump.In this paper,a new method of bionic structure is proposed for the blade surface of a centrifugal pump,which is inspired by the fish scale and comprises a leading edge,a trailing edge,and two symmetrical side edges.This fish scale structure is applied to the blade pressure and suction surfaces,and an impeller with a fish scale structure is constructed.A test rig for a centrifugal pump is developed to determine the pressure fluctuation in the pump with a prototype impeller and fish scale structure impeller.Results reveal that the dominant frequency of pressure fluctuation in volute is the blade passing frequency(f_(bpf))of 193.33 Hz,which is triggered by the interaction between the tongue and the impeller.The bionic structure of the fish scale effectively suppresses the pressure fluctuation amplitude at f_(bpf).From flow rates of 0.6 Q_(d)to 1.2 Q_(d),the average suppressions in pressure fluctuation amplitudes at f_(bpf)are 20.98%,5.85%,19.20%,and 25.77%. 展开更多
关键词 Pressure fluctuation Centrifugal pump Fish scale Bionic structure Blade passing frequency
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Risk Mitigation Effectiveness of Foreign Well-Known Trademark Protection During Supply Chain Fluctuations
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作者 LI Yinge 《Chinese Business Review》 2025年第1期9-20,共12页
The global supply chain turbulence has increased the difficulty of protecting foreign well-known trademarks.Although there are many studies on cross-border trademark rights protection in academia,there is relatively l... The global supply chain turbulence has increased the difficulty of protecting foreign well-known trademarks.Although there are many studies on cross-border trademark rights protection in academia,there is relatively little research on its risk mitigation effectiveness in the context of supply chain fluctuations.Based on case studies of commercial law and data statistics,the study explores the relationship between protection efficiency and market response through legal applicability.Due to the long litigation cycle and uneven law enforcement,there are differences in market regulation,weakening the protection of well-known trademarks and exacerbating supply chain uncertainty.Strengthening international legal framework cooperation and promoting law enforcement linkage can enhance protection effectiveness.In theory,enriching the theory of cross-border trademark protection and expanding research on brand rights protection in the context of global supply chains.In practice,it helps enterprises adjust their trademark layout,avoid legal risks,and improve market competitiveness.Due to the complexity of the legal environment and limitations in data acquisition,future research will strengthen data analysis,promote international cooperation in intelligent supervision,and build a more efficient cross-border well-known trademark protection mechanism. 展开更多
关键词 supply chain resilience famous trademark risk mitigation economic fluctuations intellectual property
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Identifying time zones of power fluctuations method for photovoltaic power ramp rate optimization
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作者 You Chen Xingshuo Li +3 位作者 Xiaoyang Chen Shuye Ding Yizhi Chen Wei Wang 《Global Energy Interconnection》 2025年第5期778-789,共12页
Photovoltaic(PV)systems are being increasingly implemented in the grid,and their intermittent output fluctuations threaten the stability of the grid,thereby requiring effective power ramp control(PRRC)strategies.In th... Photovoltaic(PV)systems are being increasingly implemented in the grid,and their intermittent output fluctuations threaten the stability of the grid,thereby requiring effective power ramp control(PRRC)strategies.In this study,we proposed a power fluctuation identification method to optimize the PRRC strategy.The K-means++cluster based on DTW used in this method,which clusters the historical PV power generation data into power curves corresponding to a specific weather type(sunny,cloudy,and rainy)in a time zone.Subsequently,wavelet decomposition is applied to discretize the power curves with extreme RR overrun to accurately identify the extreme fluctuation time zones.We conducted an analysis using minute-level data from a 100 kW PV plant in Arizona,which demonstrates that the proposed method can effectively identify high-risk periods.Weather patterns within the time zones were quantitatively identified using a weather probability model.A hardware-in-the-loop experimental platform was employed to validate two days of actual power data in Arizona,demonstrating the weather zoning accuracy of the method and the reasonableness of the control.The proposed methodology contributes significantly to PRRC strategy selection and parameter optimization(e.g.,ESS capacity storage allocation and APC power reserveΔP)in different time zones and weather conditions. 展开更多
关键词 Photovoltaic power fluctuation Temporal clustering Wavelet decomposition Power ramp rate control
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Water level fluctuations shape phytoplankton community in the Xiangxi Bay from Three Gorges Reservoir
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作者 Lingchao Fang Wujuan Mi +2 位作者 Yuan Li Xiaohan Ai Yonghong Bi 《Journal of Environmental Sciences》 2025年第11期111-122,共12页
Water level fluctuations(WLFs)constituted a dominant factor controlling the structure and function of freshwater ecosystems but the mechanism of WLFs on phytoplankton community structure was still unknown.We investiga... Water level fluctuations(WLFs)constituted a dominant factor controlling the structure and function of freshwater ecosystems but the mechanism of WLFs on phytoplankton community structure was still unknown.We investigated the characteristics of phytoplankton community structure in Xiangxi Bay from January 2017 to December 2020.Results indicated water level(WL)of the Three Gorges Reservoir was divided into four distinct stages:the decreasing stage(DS),the low water level stage(LS),the storage stage(SS),and the high water level stage(HS).Notably,Cyanophyta predominated during the LS,with Microcystis sp.being the dominant species.Bacillariophyta was predominant in other three WL stages,with Melosira sp.and Cyclotella sp.as the dominant species.The highest biomass appeared in LS,whereas the lowest appeared in HS.Moreover,alpha diversity appeared to be lower in both HS and LS compared to DS and SS.Redundancy analysis showed WL as the key driver of phytoplankton community.Partial least squares path model analyses demonstrated that WL not only altered chemical factors(path coefficient=-0.62,P<0.01),thereby leading to changes in phytoplankton biomass(path coefficient=0.56,P<0.01),but also changed the physical factors(path coefficient=-0.69,P<0.01)and consequently had an impact on phytoplankton biomass(path coefficient=0.33,P<0.01).Furthermore,WL influenced phytoplankton diversity by altering chemical and physical factors.In conclusion,WL was an important factor influencing phytoplankton community,which implied that reservoir operation was the potential strategy to regulate phytoplankton communities. 展开更多
关键词 Water level fluctuations(WLFs) Phytoplankton community Xiangxi Bay(XXB)
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Flow and fluctuation of molten steel under permanent magnet flow control-mold in continuous casting process
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作者 Ze-feng Han En-gang Wang +1 位作者 Ze-peng Wang Zhong-xin Zhai 《Journal of Iron and Steel Research International》 2025年第7期1869-1881,共13页
A new flow control technology in continuous casting process named permanent magnet flow control-mold(PMFC-Mold)was proposed,in which the permanent magnets are arranged in Halbach array near the narrow region of the mo... A new flow control technology in continuous casting process named permanent magnet flow control-mold(PMFC-Mold)was proposed,in which the permanent magnets are arranged in Halbach array near the narrow region of the mold.The behavior of molten steel flow and the fluctuation of molten steel/slag interface in the PMFC-Mold under different continuous casting speeds were investigated.Firstly,a physical experiment of liquid Ga-In-Sn alloy circulating flow was carried out in Perspex mold with Halbach’s permanent magnets(HPMs)to investigate the magnetic field distribution of HPMs and its impactful electromagnetic braking effect.The numerical simulation of 1450 mm×230 mm slab shows that a stronger magnetic field over 0.3-0.625 T is formed at the wide surface and the narrow surface of the mold,which provides an effective electromagnetic braking for controlling the impingement of molten steel jet and suppressing the fluctuation of molten steel/slag interface.The numerical simulation results show that in the PMFC-Mold,the region with the turbulent kinetic energy greater than 0.01 and 0.04 m^(2)s^(-2)on the upper backflow zone and near the narrow surface of the mold are significantly reduced.The maximum turbulent kinetic energy of the submerged entry nozzle(SEN)jet in front of the narrow surface is significantly reduced,and the SEN jet moves downward before impacting the narrow surface of the mold.In the PMFC-Mold,the region with the surface velocity greater than 0.2 m s^(-1)on the steel/slag interface is eliminated,the flow pattern and fluctuation profiles on the molten steel/slag interface become regular on both sides of SEN,and the vortex near SEN disappears.The maximum fluctuation height of molten steel/slag interface is controlled below 2.59 and 5.40 mm corresponding to the casting speed of 1.6 and 2.0 m min-1,respectively. 展开更多
关键词 Electromagnetic braking Permanent magnet flow control-mold Casting speed Molten steel flow Level fluctuation
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Experimental Study of a Helium Sorption Cooler with Low Temperature Fluctuation and Long Hold Time below 1 K
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作者 Tianshuo Liu Xiaoyu Cui +6 位作者 Lihao Lu Kongkuai Ying Yang Wang Kangjun Liu Zilong Wang Zhenhua Jiang Shaoshuai Liu 《Frontiers in Heat and Mass Transfer》 2025年第3期739-750,共12页
Helium sorption cooler technology is a key means to realize highly reliable low-vibration very lowtemperature environments,which have important applications in fields such as quantum computing and space exploration.Th... Helium sorption cooler technology is a key means to realize highly reliable low-vibration very lowtemperature environments,which have important applications in fields such as quantum computing and space exploration.The laboratory designed a superfluid suppression small hole and a multi-ribbed condenser,developed a reliable-performance helium sorption cooler(HSC),and conducted experimental studies.Experimental results show that the prototype can achieve the lowest cooling temperature of 873 mK without load by filling 6MPa helium at room temperature.The low-temperature hold time is 26 h,and the temperature fluctuation is within 0.8 mK.The cooling power of the helium sorption cooler is 1 mW@0.98 K@3.5 h.Experimental results indicate that when the charging pressure is reduced to 4MPa,theminimum temperature decreases to 836mK,and the hold time shortens to 16 h.When the pre-cooling temperature increases from 3.9 to 4.9 K,the hold time is reduced to 3 h. 展开更多
关键词 Helium sorption cooler low temperature condenser superfluid suppression hold time temperature fluctuation experimental study
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Multiphoton intravital microscopy in small animals of long-term mitochondrial dynamics based on super-resolution radial fluctuations
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作者 Saeed Bohlooli Darian Jeongmin Oh +8 位作者 Bjorn Paulson Minju Cho Globinna Kim Eunyoung Tak Inki Kim Chan-Gi Pack Jung-Man Namgoong In-Jeoung Baek Jun Ki Kim 《Opto-Electronic Advances》 2025年第7期6-21,共16页
We developed an imaging technique combining two-photon computed super-resolution microscopy and suction-based stabilization to achieve the resolution of the single-cell level and organelles in vivo.To accomplish this,... We developed an imaging technique combining two-photon computed super-resolution microscopy and suction-based stabilization to achieve the resolution of the single-cell level and organelles in vivo.To accomplish this,a conventional two-photon microscope was equipped with a 3D-printed holders,which stabilize the tissue surface within the focal plane of immersion objectives.Further computational image stabilization and noise reduction were applied,followed by superresolution radial fluctuations(SRRF)analysis,doubling image resolution,and enhancing signal-to-noise ratios for in vivo subcellular process investigation.Stabilization of<1μm was obtained by suction,and<25 nm were achieved by subsequent algorithmic image stabilization.A Mito-Dendra2 mouse model,expressing green fluorescent protein(GFP)in mitochondria,demonstrated the potential of long-term intravital subcellular imaging.In vivo mitochondrial fission and fusion,mitochondrial status migration,and the effects of alcohol consumption(modeled as an alcoholic liver disease)and berberine treatment on hepatocyte mitochondrial dynamics are directly observed intravitally.Suction-based stabilization in two-photon intravital imaging,coupled with computational super-resolution holds promise for advancing in vivo subcellular imaging studies. 展开更多
关键词 SRRF in vivo subcellular imaging mitochondiral dynamics multiphoton intravital microscopy super resolution radial fluctuations
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Association between weight fluctuation and the risk of metabolic dysfunction-associated steatotic liver disease
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作者 Jin-Ping Wang Jia-Yang Wang +5 位作者 Pei-Qi Sun Xue-Wei Wang Ze-Ting Yuan Qin Cao Shu-Ming Pan Yuan-Ye Jiang 《World Journal of Hepatology》 2025年第5期101-114,共14页
BACKGROUND The global incidence of metabolic dysfunction-associated steatotic liver disease(MASLD)has increased in recent years.It has already been demonstrated that exercise and weight change are associated with the ... BACKGROUND The global incidence of metabolic dysfunction-associated steatotic liver disease(MASLD)has increased in recent years.It has already been demonstrated that exercise and weight change are associated with the occurrence of MASLD;however,the association between weight fluctuation caused by different exercise intensities and the risk of MASLD remains to be studied.AIM To investigate the impact of weight fluctuation and physical activity intensity on the risk of MASLD prevalence.METHODS Data from the National Health and Nutrition Examination Survey database including five cycles from 2009 to 2018 were analyzed.The model included variables such as age,sex,and poverty income ratio.Weighted multivariate logistic regression was used to examine the influence of different weight fluctuation patterns within the two time intervals on the prevalence of MASLD.Nonparametric restricted cubic spline curves were used to analyze the non-linear relationship between net weight change and MASLD prevalence.RESULTS Among 3183 MASLD cases,the risk of MASLD increased with age for individuals transitioning from non-obese to obese or maintaining obesity,with odds ratio(OR)changing from 8.91(95%CI:7.40-10.88)and 11.87(95%CI:9.65-14.60)at 10 years before baseline to 9.58(95%CI:8.08-11.37)and 12.51(95%CI:9.33-16.78)at 25 years.Stable obesity correlated with age-dependent MASLD prevalence escalation,whereas increased physical activity attenuated MASLD risk in this group,with an OR changing from 13.64(95%CI:10.59-17.57)to 6.42(95%CI:4.24-9.72).Further analysis of the net weight changes revealed a paradoxical risk elevation with intensified physical activity during different time periods.CONCLUSION The risk of MASLD increases in individuals transitioning from non-obese to obese or maintaining obesity.Highintensity physical activity is beneficial for MASLD among individuals with stable obesity. 展开更多
关键词 Metabolic dysfunction-associated steatotic liver disease Metabolic dysfunction-associated steatohepatitis Weight fluctuation Body mass index Net weight Physical activity intensity
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Loop-Current Fluctuations Mediated Chiral d-Wave Pairing in Kagome Lattice
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作者 Qi-Fang Li Gaopei Pan +4 位作者 Xu Zhang Satoru Nakatsuji Weilun Jiang Xiao Yan Xu Xianxin Wu 《Chinese Physics Letters》 2025年第5期123-139,共17页
Recent various experiments have provided evidence supporting the emergence of loop-current order in kagome metals. Particularly superconductivity in AV_(3)Sb_(5) is significantly enhanced when this charge order is sup... Recent various experiments have provided evidence supporting the emergence of loop-current order in kagome metals. Particularly superconductivity in AV_(3)Sb_(5) is significantly enhanced when this charge order is suppressed by pressure or doping. Distinct from magnetic order, loop-current order does not couple directly to spin and thus whether such fluctuations can enhance superconductivity remains elusive. We design a sign problem-free bilayer kagome model coupled to quantum Ising spins through bond currents and perform determinant quantum Monte Carlo simulations to explore single-particle properties and superconductivity arising from 2 × 2 loopcurrent fluctuations. We find that this loop-current order induces intriguing band folding, band broadening,and gap opening around saddle points. Remarkably, our pairing susceptibility analysis identifies a dominant enhancement of superconductivity due to loop-current fluctuations, with the dominant pairing being the chiral d-wave channel. This pairing primarily occurs within the intra-sublattice channel and involves third nearestneighbor sites, attributed to the unique sublattice texture associated with van Hove singularities. We also discuss potential experimental implications for kagome superconductors. 展开更多
关键词 kagome metals quantum ising spins quantum monte carlo simulations bond current enhance superconductivity chiral d wave pairing loop current fluctuations kagome lattice
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A nonlinear k_p-ε_p particle two-scale turbulence model and its application 被引量:3
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作者 Zhuoxiong Zeng Zhuozhi Zeng Yihua Xu 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2007年第6期621-625,共5页
A particle nonlinear two-scale kp-εp turbulence model is proposed for simulating the anisotropic turbulent two-phase flow. The particle kinetic energy equation for two-scale fluctuation, particle energy transfer rate... A particle nonlinear two-scale kp-εp turbulence model is proposed for simulating the anisotropic turbulent two-phase flow. The particle kinetic energy equation for two-scale fluctuation, particle energy transfer rate equation for large-scale fluctuation, and particle turbulent kinetic energy dissipation rate equation for small-scale fluctuation are derived and closed. This model is used to simulate gas-particle flows in a sudden-expansion chamber. The simulation is com- pared with the experiment and with those obtained by using another two kinds of tow-phase turbulence model, such as the single-scale k-ε two-phase turbulence model and the particle two-scale second-order moment (USM) two-phase turbulence model. It is shown that the present model gives simulation in much better agreement with the experiment than the single-scale k-ε two-phase turbulence model does and is almost as good as the particle two-scale USM turbu-lence model. 展开更多
关键词 Gas-particle flows Second-order moment model two-scale fluctuation
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A two-scale second-order moment two-phase turbulence model for simulating dense gas-particle flows 被引量:5
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作者 Zhuoxiong Zeng Lixing Zhou Jian Zhang 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2005年第5期425-429,共5页
A two-scale second-order moment two-phase turbulence model accounting for inter-particle collision is developed, based on the concepts of particle large-scale fluctuation due to turbulence and particle small-scale flu... A two-scale second-order moment two-phase turbulence model accounting for inter-particle collision is developed, based on the concepts of particle large-scale fluctuation due to turbulence and particle small-scale fluctuation due to collision and through a unified treatment of these two kinds of fluctuations. The proposed model is used to simulate gas-particle flows in a channel and in a downer. Simulation results are in agreement with the experimental results reported in references and are near the results obtained using the sin- gle-scale second-order moment two-phase turbulence model superposed with a particle collision model (USM-θ model) in most regions. 展开更多
关键词 Gas-particle flows .Second-order moment model . two-scale fluctuation
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A Statistical Method for Characterizing CMOS Process Fluctuations in Subthreshold Current Mirrors 被引量:2
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作者 张雷 余志平 贺祥庆 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2008年第1期82-87,共6页
A novel method to characterize CMOS process fluctuations in subthreshold current mirrors (SCM) is reported. The proposed model is succinct in methodology and calculation complexity compared with previous statistical... A novel method to characterize CMOS process fluctuations in subthreshold current mirrors (SCM) is reported. The proposed model is succinct in methodology and calculation complexity compared with previous statistical models. However,it provides favorable estimations of CMOS process fluctuations on the SCM circuit, which makes it promising for engineering applications. The model statistically abstracts physical parameters, which depend on the IC process, into random variables with certain mean values and standard deviations, while aggregating all the random impacts into a discrete martingale. The correctness of the proposed method is experimentally verified on an SCM circuit implemented in an SMIC 0.18μm CMOS 1P6M mixed signal process with a conversion factor of 100 in an input range from 100pA to lμA. The pro- posed theory successfully predicts - 10% of die-to-die fluctuation measured in the experiment, and also suggests the -lmV of threshold voltage standard deviation over a single die,which meets the process parameters suggested by the design kit from the foundry. The deviations between calculated probabilities and measured data are less than 8%. Meanwhile, pertinent suggestions concerning high fluctuation tolerance subthreshold analog circuit design are also made and discussed. 展开更多
关键词 CMOS process fluctuations subthreshold current mirror random variable PROBABILITY discrete martingale
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New seismic attribute:Fractal scaling exponent based on gray detrended fluctuation analysis 被引量:1
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作者 黄亚平 耿建华 郭彤楼 《Applied Geophysics》 SCIE CSCD 2015年第3期343-352,467,共11页
Seismic attributes have been widely used in oil and gas exploration and development. However, owing to the complexity of seismic wave propagation in subsurface media, the limitations of the seismic data acquisition sy... Seismic attributes have been widely used in oil and gas exploration and development. However, owing to the complexity of seismic wave propagation in subsurface media, the limitations of the seismic data acquisition system, and noise interference, seismic attributes for seismic data interpretation have uncertainties. Especially, the antinoise ability of seismic attributes directly affects the reliability of seismic interpretations. Gray system theory is used in time series to minimize data randomness and increase data regularity. Detrended fluctuation analysis (DFA) can effectively reduce extrinsic data tendencies. In this study, by combining gray system theory and DFA, we propose a new method called gray detrended fluctuation analysis (GDFA) for calculating the fractal scaling exponent. We consider nonlinear time series generated by the Weierstrass function and add random noise to actual seismic data. Moreover, we discuss the antinoise ability of the fractal scaling exponent based on GDFA. The results suggest that the fractal scaling exponent calculated using the proposed method has good antinoise ability. We apply the proposed method to 3D poststack migration seismic data from southern China and compare fractal scaling exponents calculated using DFA and GDFA. The results suggest that the use of the GDFA-calculated fractal scaling exponent as a seismic attribute can match the known distribution of sedimentary facies. 展开更多
关键词 Seismic attribute gray system theory detrended fluctuation analysis fractal scaling exponent
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Effects of salinity fluctuation and dietary protein/ carbohydrate ratio on the survival and growth of Juvenile Litopenaeus vannamei 被引量:1
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作者 王兴强 曹梅 阎斌伦 《Marine Science Bulletin》 CAS 2010年第2期61-73,共13页
A factorial study was conducted to determine the effects of salinity (constant (SO) and fluctuating (S10)) and isoenergetic diet of different protein/carbohydrate ratios (P/C: 4.1, 1.9, 1.0 and 0.6) on the su... A factorial study was conducted to determine the effects of salinity (constant (SO) and fluctuating (S10)) and isoenergetic diet of different protein/carbohydrate ratios (P/C: 4.1, 1.9, 1.0 and 0.6) on the survival and growth of juvenile Litopenaeus vannamei. The experiment lasted for 35 days. The results showed that I) At S0 and S10, specific growth rate and apparent digestibility coefficient exhibited decreasing trend, while food conversion ratio exhibited increasing trend, with decreasing P/C ratio. At SO, food consumption and specific growth rate of the shrimp fed 4.1 P/C were significantly higher than those fed 1.0 and 0.6 P/C, whereas at S10, no significant differences were detected among different treatments; II) At 4.1 and 1.9 P/C, food consumption and specific growth rate were higher in the shrimp maintained at SO as compared with those at S10, while at 1.0 and 0.6 P/C, an inverse trend was observed. Among four P/C ratios, food conversion ratio of the shrimp at SO was the lowest. 展开更多
关键词 Litopenaeus vannamei salinity fluctuation protein/carbohydrate ratio SURVIVAL growth
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