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Robust Hyper-Polarization Protocol of Nuclear Spins via Magic Sequence
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作者 Haiyang Li Yongju Li +1 位作者 Hao Liao Ping Wang 《Chinese Physics Letters》 2026年第1期105-128,共24页
Hyperpolarization of nuclear spins is crucial for advancing nuclear magnetic resonance and quantum information technologies,as nuclear spins typically exhibit extremely low polarization at room temperature due to thei... Hyperpolarization of nuclear spins is crucial for advancing nuclear magnetic resonance and quantum information technologies,as nuclear spins typically exhibit extremely low polarization at room temperature due to their small gyromagnetic ratios.A promising approach to achieving high nuclear spin polarization is transferring the polarization of electrons to nuclear spins.The nitrogen-vacancy(NV)center in diamond has emerged as a highly effective medium for this purpose,and various hyperpolarization protocols have been developed.Among these,the pulsed polarization(PulsePol)method has been extensively studied due to its robustness against static energy shifts of the electron spin.In this work,we present a novel polarization protocol and uncover a family of magic sequences for hyperpolarizing nuclear spins,with PulsePol emerging as a special case of our general approach.Notably,we demonstrate that some of these magic sequences exhibit significantly greater robustness compared to the PulsePol protocol in the presence of finite half𝜋pulse duration of the protocol,Rabi and detuning errors.This enhanced robustness positions our protocol as a more suitable candidate for hyper-polarizing nuclear spins species with large gyromagnetic ratios and also ensures better compatibility with high-efficiency readout techniques at high magnetic fields.Additionally,the generality of our protocol allows for its direct application to other solid-state quantum systems beyond the NV center. 展开更多
关键词 transferring polarization electrons hyperpolarization protocols quantum information technologiesas nuclear spins pulse polarization nuclear spin polarization magic sequences nuclear magnetic resonance
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A highly robust bionic polarization orientation method for night applications
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作者 Xiaojie LIU Jun LIU +5 位作者 Pengwei HU Xin LIU Huiliang CAO Chenguang WANG Chong SHEN Jun TANG 《Chinese Journal of Aeronautics》 2026年第1期425-435,共11页
Autonomous navigation is a key technology for unmanned motion platforms to perform their tasks smoothly.The current approaches for daytime polarization navigation have been extensively researched.However,the polarizat... Autonomous navigation is a key technology for unmanned motion platforms to perform their tasks smoothly.The current approaches for daytime polarization navigation have been extensively researched.However,the polarization light intensity is the fundamental information within the polarization image,and the light intensity at night is 6-8 orders of magnitude lower than that during the day,which increase the noise and the loss of local polarization information due to occlusion,resulting in a significant decrease in the polarization orientation accuracy.Aimed at the problem,a bio-inspired model is introduced to denoise and enhance weak nighttime polarization patterns.Further,to address the issue of outlier interference in the occluded environment during practical application,a fast-fitting method of the solar meridian based on the anti-symmetric distribution of the polarization angle adjusted by Proportional and Differential(PD)control is proposed.The experimental results show that the method proposed in this paper achieves a dynamic orientation error Root Mean Square Error(RMSE)of 0.7°in the weak polarization mode at night and in the presence of local occlusion.The proposed method has strong robustness under weak polarization occlusion at night,and the orientation accuracy is improved by 97%and 80%in comparison to the least squares method,which provides a new method for polarization navigation at night.This effectively improves the robustness and environmental applicability of the bionic polarization compass for nighttime applications. 展开更多
关键词 Autonomous navigation Occlusion environment polarized light compass Spatiotemporal summation enhancement Unmanned motion platforms Weak polarization
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DLG3 Promotes Breast Cancer Cell Proliferation and Migration by Mediating STAT3 Activation
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作者 Khalid Idris GIDADO Rabiu LAWAN +4 位作者 PENG Xixia ZHANG Ziyang WAN Xiaochun LU Zhen ZHANG Guizhong 《集成技术》 2026年第1期41-55,共15页
Breast cancer(BRCA)is characterized by high heterogeneity,with aggressive subtypes frequently showing poor prognosis and resistance to conventional therapies,making the discovery of new therapeutic targets and strateg... Breast cancer(BRCA)is characterized by high heterogeneity,with aggressive subtypes frequently showing poor prognosis and resistance to conventional therapies,making the discovery of new therapeutic targets and strategies imperative.Although elevated expression of discs large homolog 3(DLG3)has been reported in BRCA,its functional role in disease progression remains unclear.We performed bioinformatic analyses of clinical datasets to evaluate the prognostic significance of DLG3 expression in BRCA patients.In vitro gain-and loss-of-function experiments were conducted to assess the impact of DLG3 on BRCA cell proliferation,migration,and colony formation.Transcriptomic profiling,coupled with pharmacological inhibition,was employed to identify and validate downstream signaling pathways.Additionally,we extended our validation to an in vivo model to assess the role of DLG3 in tumor progression.We found that elevated DLG3 levels correlated with poor prognosis in breast cancer patients.Functionally,DLG3 overexpression significantly promoted cell proliferation and migration in estrogen receptor-positive MCF7 and triple-negative MDA-MB-231 breast cancer cells,whereas its knockdown suppressed these effects.Transcriptomic analyses revealed that DLG3 activates signal transducer and activator of transcription 3(STAT3)signaling,a finding further corroborated by Western blot.Critically,treatment with the STAT3 inhibitor Stattic attenuated DLG3-driven proliferation and migration,supporting a DLG3-STAT3 oncogenic axis.Furthermore,in vivo studies validated the role of DLG3 in promoting tumor growth and its correlation with elevated STAT3 signaling,consistent with our in vitro findings.Our findings establish DLG3 as a novel driver of breast cancer progression that directly activates STAT3 signaling.DLG3 thus represents both a potential prognostic biomarker and a promising therapeutic target for aggressive breast cancer subtypes,including triple-negative breast cancer. 展开更多
关键词 breast cancer DLG3 STAT3 PROLIFERATION migration
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Reduction and migration behavior of phosphorus in coal-based reduction of high-phosphorus oolitic iron ore
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作者 Meng-Jie Hu De-Qing Zhu +4 位作者 Jian Pan Zheng-Qi Guo Cong-Cong Yang Si-Wei Li Wen Cao 《Journal of Iron and Steel Research International》 2026年第3期88-105,共18页
Phosphorus tends to migrate into metallic iron during the direct reduction of high-phosphorus oolitic iron ore,leading to undesirable phosphorus enrichment in metallic iron.However,the underlying reduction and migrati... Phosphorus tends to migrate into metallic iron during the direct reduction of high-phosphorus oolitic iron ore,leading to undesirable phosphorus enrichment in metallic iron.However,the underlying reduction and migration mechanisms remain poorly understood.Phosphorus behavior during coal-based reduction was systematically investigated through theoretical modeling and experimental approaches.Thermodynamic analysis revealed that the carbon reduction of solid Ca_(3)(PO_(4))_(2)to gaseous P_(2)requires temperatures exceeding 1400℃.Notably,this threshold significantly decreases to 1130.5℃in the presence of SiO_(2)and Al_(2)O_(3).Further investigations demonstrated that Ca_(3)(PO_(4))_(2)co-reduces with Fe_(x)O_(γ)in the presence of SiO_(2)-Al_(2)O_(3)-Fe_(x)O_(γ),forming Fe_(3)P(instead of gaseous P_(2))at a markedly lower temperature of 778.7℃.Mechanistic studies indicate that the inherent thermal stability of Ca_(3)(PO_(4))_(2)inhibits the generation of reactive[P_(2)O_(5)].However,SiO_(2)-Al_(2)O_(3)coexistence destabilizes Ca_(3)(PO_(4))_(2)while exponentially enhancing[P_(2)O_(5)]activity.This synergistic effect dramatically promotes the phosphorus mineral reduction.Characterization confirmed that Ca_(3)(PO_(4))_(2)migrated into the slag phase(4FeO·Al_(2)O_(3)·3SiO_(2)·CaO·P_(2)O_(5)).Subsequently,the reactive P_(2)O_(5)in slag is reduced with metallic iron to form Fe_(3)P,which further dissolves into theα-Fe matrix through solid-state diffusion,ultimately generating Fe-P solid solutions. 展开更多
关键词 Oolitic hematite ore Coal-based reduction migration behavior DEPHOSPHORIZATION
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Broadband polarization-based method for color high-resolution imaging through complex scattering media
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作者 Sen Wang Tianyu Wang +7 位作者 Piao He Yan Hui Xue Dong Jinpeng Liu Jingjing Ge Fei Liu Meng Xiang Xiaopeng Shao 《Advanced Photonics Nexus》 2026年第1期236-247,共12页
In complex media scattering,multiple scattering severely degrades the optical wavefront and results in blurred images,while the spectral distortion caused by the scattering effect leads to severe color distortion.Achi... In complex media scattering,multiple scattering severely degrades the optical wavefront and results in blurred images,while the spectral distortion caused by the scattering effect leads to severe color distortion.Achieving color high-resolution imaging through scattering media remains a significant challenge.Here,we propose a broadband,polarization-based method for color high-resolution imaging through scattering media.This approach enables high-resolution reconstruction by effectively separating the speckle illumination pattern from the mixed-scattering field information,leveraging polarization common-mode characteristics.Concurrently,it incorporates chromatic balance compensation to correct spectral aliasing in the scattered light field,enabling color high-resolution imaging through complex scattering media.To further optimize color distortion caused by scattering,a compensation strategy combining color constancy and white balance theory is adopted.Experimental results demonstrate that the proposed method significantly enhances both spatial resolution and color fidelity across various scattering conditions and target materials,showcasing strong adaptability and robustness.This approach provides an effective solution for achieving high-resolution color optical imaging in complex scattering environments. 展开更多
关键词 scattering medium color imaging polarization high resolution
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First systematic identification of triple-mode Auroral Kilometric Radiation using Arase polarization data
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作者 YiHua He SanGuang Li +8 位作者 HongMing Yang Sai Zhang YuYue Jin Si Liu ZhongLei Gao FuLiang Xiao ZhaoGuo He JiaWen Tang Ping Li 《Earth and Planetary Physics》 2026年第1期117-125,共9页
Auroral kilometric radiation(AKR),a fundamental plasma emission in Earth's magnetosphere,exhibits three characteristic modes:the right-handed extraordinary(R-X),left-handed ordinary(L-O)and left-handed extraordina... Auroral kilometric radiation(AKR),a fundamental plasma emission in Earth's magnetosphere,exhibits three characteristic modes:the right-handed extraordinary(R-X),left-handed ordinary(L-O)and left-handed extraordinary(L-X)modes.The role of AKR in magnetosphere−ionosphere−atmosphere coupling depends sensitively on its wave mode.While previous studies have primarily focused on the dominant R-X mode,we present the first systematic identification of all three modes using a practical polarization analysis method based on Arase satellite observations.This method employs a spin-axis-relative Ratio:when the satellite's spin axis aligns with the background magnetic field,a positive(negative)Ratio indicates the right-handed(left-handed)polarization,with reversal under anti-parallel conditions.Combined polarization-frequency analysis reveals that R-X,L-O,and L-X modes can exist in both dayside and nightside regions,with power spectral densities up to 10^(-6)mV^(2)m^(-2)Hz^(-1).This study resolves long-standing ambiguities in AKR mode classification and has implications for understanding AKR-induced electron dynamics. 展开更多
关键词 Auroral kilometric radiation wave mode polarization
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Retraction:MicroRNA-133b Inhibits Proliferation,Cellular Migration,and Invasion via Targeting LASP1 in Hepatocarcinoma Cells
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作者 Oncology Research Editorial Office 《Oncology Research》 2026年第1期621-621,共1页
The published article titled“MicroRNA-133b Inhibits Proliferation,Cellular Migration,and Invasion via Targeting LASP1 in Hepatocarcinoma Cells”has been retracted from Oncology Research,Vol.25,No.8,2017,pp.1269–1282.
关键词 lasp cellular migration PROLIFERATION INVASION hepatocarcinoma cells targeting lasp microrna b
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Retraction:TRAF4 Regulates Migration,Invasion,and Epithelial-Mesenchymal Transition via PI3K/AKT Signaling in Hepatocellular Carcinoma
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《Oncology Research》 2026年第4期891-891,共1页
Oncology Research Editorial Office Published:23 March 2026 The published article titled“TRAF4 Regulates Migration,Invasion,and Epithelial-Mesenchymal Transition via PI3K/AKT Signaling in Hepatocellular Carcinoma”has... Oncology Research Editorial Office Published:23 March 2026 The published article titled“TRAF4 Regulates Migration,Invasion,and Epithelial-Mesenchymal Transition via PI3K/AKT Signaling in Hepatocellular Carcinoma”has been retracted from Oncology Research,Vol.25,No.8,2017,pp.1329-1340.DOI:10.3727/096504017X14876227286564 URL:https://www.techscience.com/or/v25n8/56917. 展开更多
关键词 pi k akt signaling epithelial mesenchymal transition migration INVASION hepatocellular carcinoma
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Suppressing planar gliding and cation migration in O3-type layered oxide cathode for long-life and wide-temperature sodium-ion batteries
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作者 Peng Yu Nini Liu +10 位作者 Yizhong Gou Daomin Qin Wen Zhang Lihua Feng Yameng Fan Yu Wang Changhong Wang Jiantao Han Yunhui Huang Jian Peng Chun Fang 《Journal of Energy Chemistry》 2026年第2期789-799,I0017,共12页
Sodium layered oxides stand out as one of the most promising cathodes for sodium-ion batteries due to their high energy density,elemental abundance,and scalability.However,their practical applications are restricted b... Sodium layered oxides stand out as one of the most promising cathodes for sodium-ion batteries due to their high energy density,elemental abundance,and scalability.However,their practical applications are restricted by interplanar gliding,cation migration,and the formation of intragranular microcracks,which collectively lead to rapid structural degradation and capacity loss.Herein,we rationally design an ultrastable O3-type Na_(0.94)Ca_(0.03)Ni_(1/3)Fe_(1/3)Mn_(1/3)O_(2) cathode,in which Ca^(2+)cations act as pillars within the NaO_(2)slabs,suppressing the irreversible phase transitions and Na/TM cation migration commonly observed in layered oxides.Multiscale in situ and ex situ techniques,combined with post-mortem analysis,reveal that the Ca-pillared pinning effect not only effectively suppresses the interplanar gliding and stress accumulation within the crystal phase but also restrains Na/TM cation migration and surface reconstruction in near-surface regions.Benefiting from the combined effects of structural stabilization,the Ca-pillared cathode exhibits a superior cycling stability,retaining 81.6%of its capacity after 1000 cycles at 2 C within the voltage range of 2.0-4.0 V,along with significantly enhanced wide-temperature(from-40 to 80℃)performance.This work highlights another critical role of Ca pillars in suppressing cation migration and surface structural degradation beyond preventing adverse interplanar gliding,offering valuable insights for designing long-life and wide-temperature layered oxide cathodes. 展开更多
关键词 Layered oxide cathodes Pinning effect Planar gliding Cation migration Sodium-ion batteries
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Influence of Soft Segment Length on the Dielectric Polarization Behavior of Ketal-containing Polyurethane Elastomer
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作者 Xue Mei Wan Lu +6 位作者 Jian-Rong Dong Ke-Heng Pan Jun-Jie Tan Hong-Ye Yan Jun Wu Yu Zhou Hong-Xiang Chen 《Chinese Journal of Polymer Science》 2026年第1期189-197,I0015,共10页
Polyurethane elastomers exhibit high dielectric constants owing to their polar groups,and can be used as energy storage capacitors.Energy storage depends not only on the dielectric constant but also on the dielectric ... Polyurethane elastomers exhibit high dielectric constants owing to their polar groups,and can be used as energy storage capacitors.Energy storage depends not only on the dielectric constant but also on the dielectric loss.However,the relationship between chain structure and dielectric properties is not yet clear.Ketal-containing crosslinked polyurethane elastomers were prepared using cyclic ketal diol as a chain extender.The effect of the soft segment length on the dielectric properties and energy storage was investigated.The cause of the change in the dipolar polarization with the soft segment length was analyzed.As the soft segment length increased,the hard-soft hydrogen bonding decreased,whereas the hard-hard hydrogen bonding increased.Under the action of an electric field,the polar bonds in the ketal-containing polyurethane elastomer overcome the hydrogen bonding between hard-soft segments to produce polarization;meanwhile,they also experience crankshaft motions to generate polarization.The former has a relatively high relaxation activation energy of approximately 10-20 k J·mol^(-1),resulting in a large dielectric loss.The latter has a relatively low relaxation activation energy,approximately 0.7-1.7 kJ·mol^(-1),leading to low dielectric loss.As a result,the dielectric constant showed a decreasing trend,and the dielectric loss gradually decreased.This study provides a theoretical foundation for improving the dielectric properties of polyurethane elastomers. 展开更多
关键词 Dielectric polarization Polyurethane elastomer Soft segment length Intermolecular interaction
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Cell type-dependent role of transforming growth factor-βsignaling on postnatal neural stem cell proliferation and migration
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作者 Kierra Ware Joshua Peter +1 位作者 Lucas McClain Yu Luo 《Neural Regeneration Research》 2026年第3期1151-1161,共11页
Adult neurogenesis continuously produces new neurons critical for cognitive plasticity in adult rodents.While it is known transforming growth factor-βsignaling is important in embryonic neurogenesis,its role in postn... Adult neurogenesis continuously produces new neurons critical for cognitive plasticity in adult rodents.While it is known transforming growth factor-βsignaling is important in embryonic neurogenesis,its role in postnatal neurogenesis remains unclear.In this study,to define the precise role of transforming growth factor-βsignaling in postnatal neurogenesis at distinct stages of the neurogenic cascade both in vitro and in vivo,we developed two novel inducible and cell type-specific mouse models to specifically silence transforming growth factor-βsignaling in neural stem cells in(mGFAPcre-ALK5fl/fl-Ai9)or immature neuroblasts in(DCXcreERT2-ALK5fl/fl-Ai9).Our data showed that exogenous transforming growth factor-βtreatment led to inhibition of the proliferation of primary neural stem cells while stimulating their migration.These effects were abolished in activin-like kinase 5(ALK5)knockout primary neural stem cells.Consistent with this,inhibition of transforming growth factor-βsignaling with SB-431542 in wild-type neural stem cells stimulated proliferation while inhibited the migration of neural stem cells.Interestingly,deletion of transforming growth factor-βreceptor in neural stem cells in vivo inhibited the migration of postnatal born neurons in mGFAPcre-ALK5fl/fl-Ai9 mice,while abolishment of transforming growth factor-βsignaling in immature neuroblasts in DCXcreERT2-ALK5fl/fl-Ai9 mice did not affect the migration of these cells in the hippocampus.In summary,our data supports a dual role of transforming growth factor-βsignaling in the proliferation and migration of neural stem cells in vitro.Moreover,our data provides novel insights on cell type-specific-dependent requirements of transforming growth factor-βsignaling on neural stem cell proliferation and migration in vivo. 展开更多
关键词 adult neurogenesis DOUBLECORTIN HIPPOCAMPUS migration neural stem cells PROLIFERATION transforming growth factor-β
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Redundant source-wavelet amplitude influence in wave-equation migration/demigration flow and its removal
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作者 QianCheng Liu JiaLe Kang Jie Li 《Earth and Planetary Physics》 2026年第1期75-81,共7页
In wave-equation migration and demigration,the cross-correlation imaging/forwarding step implicitly injects an additional copy of the source wavelet,so that the amplitude spectrum of the wavelet is applied redundantly... In wave-equation migration and demigration,the cross-correlation imaging/forwarding step implicitly injects an additional copy of the source wavelet,so that the amplitude spectrum of the wavelet is applied redundantly(effectively imposing a wavelet-spectrum weighting,often akin to an amplitude-squared bias).This redundancy degrades structural fidelity and amplitude balance yet is frequently overlooked.We(i)formalize the mechanism by which cross-correlation duplicates the source-wavelet amplitude effect in both migration and demigration,and(ii)introduce a source-equalized operator that removes the redundancy by deconvolving(or dividing by)the wavelet amplitude spectrum in the imaging condition and its demigration counterpart,while leaving phase/kinematics intact.Using a band-limited Ricker wavelet on a two-layer model and on Marmousi,we show that,if unmanaged,the redundant wavelet spectrum broadens main lobes,introduces ringing,and suppresses vertical resolution in migrated images,and inflates spectrum mismatches between demigrated and observed data even when peak times agree.With our correction,images recover observed-data-consistent bandwidth and sharpened interfaces,and demigrated data also exhibit improved spectrum conformity and reduced amplitude misfit.The results clarify when source amplitudes matter,why cross-correlation makes them redundantly matter,and how a lightweight spectral correction restores physically meaningful amplitude behavior in wave-equation migration/demigration. 展开更多
关键词 wave-equation migration DEmigration cross-correlation imaging condition source wavelet amplitude spectrum spectral deconvolution
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First-principles insights into strain-mediated He migration and irradiation resistance in WTa-Cr-V complex alloys
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作者 Mengdie Wang Chao Zhang +2 位作者 Xinyue Lan Biao Hu Xuebang Wu 《Chinese Physics B》 2026年第1期549-556,共8页
High-performance intelligent protective materials are vital for nuclear energy systems exposed to extreme irradiation.Among them,tungsten-based alloys demonstrate exceptional potential owing to their superior irradiat... High-performance intelligent protective materials are vital for nuclear energy systems exposed to extreme irradiation.Among them,tungsten-based alloys demonstrate exceptional potential owing to their superior irradiation resistance.Recent experimental studies have demonstrated that W-Ta-Cr-V alloys exhibit excellent irradiation resistance under helium(He)ion irradiation.However,the underlying mechanisms,especially the migration behavior of He atoms,remain unclear.In this work,the influences of uniaxial tensile and compressive strain on He migration in W-Ta-Cr-V complex alloys have been systematically studied through first-principles calculations.Our results demonstrate that He atoms preferentially occupy the tetrahedral interstitial sites,with interstitial formation energies significantly reduced compared to pure W.The introduction of Ta,Cr,and V alloying elements markedly increases the He migration barriers,effectively suppressing He diffusion.Compressive strain increases the migration barriers,inhibiting He bubbles nucleation and growth,while tensile strain decreases the barriers,facilitating bubble formation.Compared to pure W,the W-Ta-Cr-V alloys exhibit both lower He interstitial formation energies and higher migration barriers,with further enhancement under compressive strain.Specifically,compressive strain of 6%increases the He migration barrier of the W-Ta-Cr-V alloy by 0.166 e V,which further widens the difference relative to pure W.These findings provide a theoretical explanation for the superior irradiation resistance of tungsten-based alloys observed experimentally and promote the understanding of irradiation damage in these alloys under strain. 展开更多
关键词 He bubbles migration barriers tensile/compressive strain W-Ta-Cr-V alloys first-principles calculations
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Electrostatic interaction tuned proton migration behavior by electron-rich Pt sites enhancing alkaline hydrogen evolution reaction
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作者 Shuping Zhang Li Zhao +5 位作者 Wenjing Yuan Pin Zhou Zhiyi Sun Qing Cao Riming Hu Jiayuan Yu 《Journal of Energy Chemistry》 2026年第3期791-798,共8页
Regulating the critical process of proton migration from water dissociation for boosting alkaline hydrogen evolution reaction(HER)remains a challenge.Herein,we propose an electrostatic attraction strategy to achieve t... Regulating the critical process of proton migration from water dissociation for boosting alkaline hydrogen evolution reaction(HER)remains a challenge.Herein,we propose an electrostatic attraction strategy to achieve the migration of a highly efficient hydrogen species to Pt sites over Pt/Co@NC,which is obtained through a facile calcination and electrodeposition method.It exhibits an outstanding geometric activity(η_(10)=31 m V),which surpasses the commercial 20 wt%Pt/C(η_(10)=37 mV).Moreover,the mass activity of Pt/Co@NC is 5.6 A mg_(Pt)^(-1) at-50 mV vs.RHE,which is 2.23 times higher than that of 20 wt%Pt/C.Experimental and theoretical results indicate that the work function of the outer carbon layer,which is changed by the introduction of the inner cobalt core,plays a crucial role in reversing the direction of electron migration between the carbon layer and Pt.The negatively charged Pt^(δ-)can spontaneously attract positively charged protons via the electrostatic interaction effect,thereby achieving the directional migration of hydrogen species.This work presents a strategy for designing advanced alkaline HER electrocatalysts by the electrostatic effect. 展开更多
关键词 Pt-based catalysts Electronic structure Proton migration Alkaline hydrogen evolution reaction Water dissociation
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Numerical study on pebble-bed powder migration and clogging mechanism with purge gas
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作者 Xue-Tao Cui Qi-Gang Wu +2 位作者 Jian Wang Ming-Zhun Lei Yun-Tao Song 《Nuclear Science and Techniques》 2026年第2期194-207,共14页
As the primary functional component of a fusion reactor,the fusion blanket pebble bed,composed of numerous particles,is crucial for tritium breeding,neutron multiplication,and radiation shielding.Particles within trit... As the primary functional component of a fusion reactor,the fusion blanket pebble bed,composed of numerous particles,is crucial for tritium breeding,neutron multiplication,and radiation shielding.Particles within tritium-breeding pebble beds are subjected to prolonged neutron irradiation,high thermal loads,and strong magnetic fields in fusion environments.Such conditions render them susceptible to pulverization and fragmentation.The resulting fragments and powders migrate and are deposited into the gas channel,driven by the purge gas.The reduction in the effective flow area of the gas increases the flow resistance,resulting in tritium retention,degraded heat transfer,and other adverse effects.These conditions impair the thermodynamic properties of the pebble beds and hinder the self-maintenance of tritium.Limited information exists on powder migration and clogging mechanisms in fusion blanket pebble beds,particularly under diverse physical conditions.The aim of this study was to use a computational fluid dynamics model coupled with the discrete element method(CFD-DEM)to numerically explore powder migration and clogging in pebble beds.The model considers factors such as breeder orientation,purge velocity,powder size distribution,and friction coefficient.We propose two migration and clogging mechanisms.One involves powder with a large particle size,and the other does not.The results indicate that the powder migration velocity progresses through three stages:rapid decay,linear decay,and stability.Pebble-bed clogging manifests in two forms:extensive superficial clogging and uniform internal clogging.Two fitted curves were used to depict the migration and clogging tendencies.The powder size distribution significantly influenced the powder migration.The breeder orientation,powder size,and friction coefficient affected the distribution of the clogging powders.However,the impact of the purge velocity on powder migration and clogging in pebble beds was limited,and this effect varied significantly with different particle size ratios.Based on the analysis,a formula is proposed to characterize the behavior of the powder in the pebble beds.The results of this study can aid in analyzing and predicting powder dynamics in pebble beds. 展开更多
关键词 Coupled CFD-DEM Pebble beds Purge gas Powder flow migration and clogging mechanism
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Effect of particle size on migration and retention of bacteria in sand and its biomineralization
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作者 Hanjiang Lai Shuiquan Deng +5 位作者 Mingjuan Cui Shaohui Zheng Junjie Zheng Runming Liu Jianwei Zhang Yu Song 《Journal of Rock Mechanics and Geotechnical Engineering》 2026年第2期1496-1503,共8页
Bacterial cells are widely accepted as nucleation sites for calcium carbonate precipitation in biomineralization based on the Microbially Induced Carbonate Precipitation(MICP)process.For MICP-based insitu biotreatment... Bacterial cells are widely accepted as nucleation sites for calcium carbonate precipitation in biomineralization based on the Microbially Induced Carbonate Precipitation(MICP)process.For MICP-based insitu biotreatment,the firstproblem to be solved is how to introduce and retain the bacterial cells in the soil,which involves the migration and retention of bacterial cells during the biogrouting process.Soil particle size,a key factor in determining pore throat size,can have a significanteffect on the migration and retention of bacterial cells in the soil and therefore on biomineralization.To investigate the effect of particle size on the migration and retention of bacterial cells in sand and its biomineralization,two sets of tests were carried out in this study,including percolation tests and sand column treatment tests.Soil urease activity(definedas urease activity per unit mass of soil)and calcium carbonate content of the biomineralized sand were measured to comprehensively assess the migration and retention of bacterial cells in the sand.The results indicate that sands with a particle size smaller than 0.25 mmwould inhibit the migration of bacteria in the sand,resulting in a nonuniform distribution of precipitated calcium carbonate and a low strength enhancement of biomineralization.On the other hand,sands with a particle size larger than 1.18 mm are unfavorable for retaining bacterial cells in the sand,resulting in low calcium conversion efficiency.Meanwhile,particle size would also affect the formation of effective calcium carbonate through interparticle contact number and interparticle pore size,and thus biomineralization. 展开更多
关键词 Microbially induced carbonate precipitation(MICP) Soil particle size Bacterial cell migration RETENTION BIOMINERALIZATION
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Cytokines IL-6,IL-10,and CCL5 Secreted by Infiltrating B Cells Promote Cell Migration of Human Prostate Cancer Cell Lines
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作者 Crystal J.Byrd Monasia Evans +2 位作者 Woojung Kim Quintera Knight Geou-Yarh Liou 《Oncology Research》 2026年第4期413-425,共13页
Objective:The progression of prostate cancer cells to metastasis is supported by their tumor microenvironment.Within this microenvironment,infiltrating immune cells,such as B cells,can be either anti-tumorigenic or pr... Objective:The progression of prostate cancer cells to metastasis is supported by their tumor microenvironment.Within this microenvironment,infiltrating immune cells,such as B cells,can be either anti-tumorigenic or pro-tumorigenic.Our preliminary data showed that a higher density of the infiltrating B cells was found near prostate cancer cells in human cancer tissues,as compared to the benign prostate tissue regions,thus suggesting that infiltrating B cells would promote the progression of prostate cancer cells.In this study,we aim to investigate the role of infiltrating B cells in enhancing the migratory ability of human prostate cancer cells.Methods:We utilized Transwell©R assays to evaluate the migratory ability of human prostate cancer cells in the presence or absence of B cells,B cell-secreted cytokines,and neutralizing antibodies of B cell-secreted cytokines.We also used Western blot and immunofluorescence staining to evaluate the effects of epithelial-mesenchymal transition on the human prostate cancer cells in response to the B cell cytokines.Results:Our findings showed an increase in migration of human prostate cancer cells in response to co-cultured B cells as well as the identified B cell cytokines:IL-6,IL-10,and CCL5.Neutralization of these cytokines through their specific neutralizing antibodies decreased B cell-induced prostate cancer cell migration.Results from Western blot and immunocytochemistry showed an increase in expression of N-cadherin and Slug,as well as disorganization of ZO-1,amongst the LNCaP cells treated with B cell cytokines.Conclusion:These results revealed that infiltrating B cells through their secretion factors enhanced prostate cancer cell migratory ability,which may lead to metastasis. 展开更多
关键词 CYTOKINES B cells human prostate cancer cells cell migration tumor microenvironment(TME)
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Waveform-matching reverse time migration for local earthquakes
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作者 Lanshu Bai Qingju Wu Ruiqing Zhang 《Earthquake Science》 2026年第2期125-139,共15页
With the increasing use of passive seismic data,developing seismic reflection imaging methods based on passive data is of considerable practical significance.This study presents a waveform-matching reverse time migrat... With the increasing use of passive seismic data,developing seismic reflection imaging methods based on passive data is of considerable practical significance.This study presents a waveform-matching reverse time migration for the primary reflected data from local earthquakes.In order to mitigate inconsistencies in frequency band and energy across earthquakes of different magnitudes,we first establish reference seismic waveform with standardized dominant frequency and magnitude.A matching operator is derived for each event by matching its waveforms with the reference waveform.This operator is then applied via convolution to all waveforms,producing standardized seismic waveforms with consistent wavelet features.The reshaped waveforms are then subjected to reverse time migration using an impedance imaging condition for primary reflections.To suppress strong energy interference near the hypocenters,both illumination compensation and three-dimensional Smoothed Spherical Mask centered on each source are used.Numerical tests using both simple two-layer model and fault-containing model demonstrate that the new method is robust and effective.The reverse time migration of primary reflected data of local earthquakes accurately images underground impedance boundaries such as stratum interfaces and fault planes,showing its promise for future application in seismically active fault zones. 展开更多
关键词 passive seismic data local earthquake waveform matching reverse time migration primary reflected data
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Shape polarization and coexistence of high-K three-quasiparticle states in odd-mass N=106 isotones
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作者 Run-Yan Dong Chang-Feng Jiao 《Nuclear Science and Techniques》 2026年第5期315-325,共11页
Three-quasiparticle K-isomeric states in odd-mass N=106 isotones within the A~180 mass region were systematically investigated using configuration-constrained potential energy surface calculations.The calculations suc... Three-quasiparticle K-isomeric states in odd-mass N=106 isotones within the A~180 mass region were systematically investigated using configuration-constrained potential energy surface calculations.The calculations succes sfully reproduced the excitation energies and deformations of the known high-K isomers in nuclei from 175Tm to 181Re.For the nuclei closer to the Z=82 shell closure(^(183)Ir,^(185)Au,and^(187)Tl),predictions of the configurations of the observed and yet-to-be-observed isomers are provided.The results reveal strong shape polarization,where the three-quasiparticle states are driven to larger deformations compared to the often shape-soft or spherical ground states.A particularly rich spectrum of shape coexistence is predicted in^(187)Tl,where several high-K three-quasiparticle configurations with distinct prolate,oblate,and triaxial shapes are found to coexist at similar excitation energies.Notably,the oblate-deformed K^(π)=29/2^(+)configuration at E_(x)=1839 keV was proposed to be responsible for a long-lived isomer.This study provides a comprehensive picture of shape evolution and coexistence in high-K multi-quasiparticle states,offering valuable insights for future experimental studies. 展开更多
关键词 Shape polarization Shape coexistence High-K isomeric state Con-guration-constrained potential energy surface
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Exosome-me diate d regulation of macrophage polarization:A novel therapeutic strategy for diabetic wound healing
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作者 Jia-Le Ma Ling-Xiao Wang +4 位作者 Hao Yu Zhi-Kang Zhu Jia-Hong Xu Jia-Qi Lou Shou-Jie Wang 《Hepatobiliary & Pancreatic Diseases International》 2026年第1期115-118,共4页
Diabetes mellitus is an escalating global health issue,with 463 million adults affected in 2019.Without intervention,this number is projected to increase to 578 million by 2030 and 700 million by 2045[1].Diabetic woun... Diabetes mellitus is an escalating global health issue,with 463 million adults affected in 2019.Without intervention,this number is projected to increase to 578 million by 2030 and 700 million by 2045[1].Diabetic wound,a significant complication,is characterized by delayed healing,high disability rates,and elevated mortality[2].The challenges of wound healing in diabetic patients,compounded by their high morbidity and mortality rates,have drawn growing attention in biomedical research. 展开更多
关键词 wound healing diabetes mellitus exosome mediated regulation diabetic wound healing biomedical research macrophage polarization
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