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Why the migration of peritoneal shunt catheter into the scrotum occurs more in children:A systematic literature review
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作者 Rajendra Kumar Ghritlaharey 《World Journal of Meta-Analysis》 2025年第2期6-26,共21页
BACKGROUND Ventriculoperitoneal shunt(VPS)catheter insertion is one of the most widely accepted surgical procedures for hydrocephalus.Migration of the end of the distal VPS catheter into the scrotum is one of the rare... BACKGROUND Ventriculoperitoneal shunt(VPS)catheter insertion is one of the most widely accepted surgical procedures for hydrocephalus.Migration of the end of the distal VPS catheter into the scrotum is one of the rare complications of VPS catheter insertion.METHODS This is a systematic review of the published cases,and the literature search was performed from 1974 to June 30,2024,to retrieve the relevant manuscripts.The cases were grouped into two.Group A included cases of migration of the distal VPS catheter into the scrotum,detected in children.Group B included the cases of migration of the distal VPS catheter into the scrotum,which was detected in adults and older people.RESULTS One hundred-twenty cases of migration of the distal end of VPS catheter into the scrotum were included in this study,a systematic literature review.Group A included n=112 cases,and group B included n=8 cases only.Three-fourths of the cases involved the right scrotum.Bilateral involvement was rare.The indication for initial VPS insertion was congenital hydrocephalus in four-fifths of the group A cases.The majority were infants at the time of initial shunt insertion.Four-fifths of the group A cases were 24 months-old or younger at the time of clinical diagnosis and treatment was provided for migration of the distal VPS catheter into the scrotum.In children,the interval from VPS insertion or shunt revision if any,to the diagnosis of the complication mentioned above was 12 months or less in four-fifths of the cases.The repositioning of migrated distal VPS catheter into the peritoneal cavity and herniotomy was preferred for the surgical procedure,and it was performed for two-thirds of group A cases.CONCLUSION Migration of the distal part of the VPS catheter into the scrotum is a rare complication of cerebrospinal fluid diversion via VPS catheter insertion.It was most frequent in children,and the right side of the scrotum was most often involved. 展开更多
关键词 INFANTS CHILDREN Complication HYDROCEPHALUS migration SCROTUM
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Stem cell-derived neural organoids as platforms to investigate glioblastoma invasion and migration:A systematic review
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作者 Arielly da Hora Alves Nicole Mastandrea Ennes do Valle +7 位作者 Bruno Yukio Yokota-Moreno Marta Caetano dos Santos Galanciak Keithy Felix da Silva Javier Bustamante Mamani Andrea Laurato Sertie Fernando Anselmo de Oliveira Mariana Penteado Nucci Lionel Fernel Gamarra 《World Journal of Stem Cells》 2025年第8期163-185,共23页
BACKGROUND Glioblastoma multiforme(GBM)is the most aggressive and prevalent primary malignant brain tumor in adults,marked by poor prognosis and high invasiveness.Traditional GBM invasion assays,such as those involvin... BACKGROUND Glioblastoma multiforme(GBM)is the most aggressive and prevalent primary malignant brain tumor in adults,marked by poor prognosis and high invasiveness.Traditional GBM invasion assays,such as those involving mouse brain xenografts,are often time-consuming and limited in efficiency.In this context,stem cell-derived neural organoids(NOs)have emerged as advanced,threedimensional,human-relevant platforms that mimic the cellular architecture and microenvironment of the human brain.These models provide novel opportunities to investigate glioblastoma stem cell invasion,a critical driver of tumor progression and therapeutic resistance.AIM To evaluate studies using stem cell-derived NOs to model glioblastoma migration/invasion,focusing on methodologies,applications and therapeutic implications.METHODS We conducted a systematic review following PRISMA guidelines,searching PubMed and Scopus for studies published between March 2019 and March 2025 that investigated NOs in the context of glioblastoma invasion/migration.After screening 377 articles based on predefined inclusion and exclusion criteria,10 original research articles were selected for analysis.Extracted data were categorized into four analytical domains:(1)Tumor model formation;(2)NO characteristics;(3)NO differentiation protocols;and(4)Invasion/migration assessment methodologies.RESULTS The included studies exhibit significant methodological heterogeneity GBM model development,particularly regarding model type,cell source and culture conditions.Most studies(70%)used suspension cell models,while 30%employed spheroids,with most research focusing on patient-derived glioblastoma stem cells.NOs were predominantly generated from human induced pluripotent stem cells using both guided and unguided differentiation protocols.Confocal fluorescence microscopy was the primary method used for assessing invasion,revealing invasion depths of up to 300μm.Organoid maturity and co-culture duration influenced results,while key factors for model optimization included tumor cell density,organoid age and extracellular matrix composition.Some studies also tested therapeutic strategies such as Zika virus and microRNA modulation.Collectively,findings support the utility of NOs as effective tools for studying GBM behavior and therapeutic responses in a humanized three-dimensional context.CONCLUSION Human NOs represent promising platforms for modeling glioblastoma invasion in a humanized three-dimensional environment.However,a limited number of studies and methodological heterogeneity hinder reproducibility.Protocol standardization is essential to enhance the translational application of these models. 展开更多
关键词 GLIOBLASTOMA Stem cell Organoid SPHEROID INVASION migration
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Exploring charge migration dynamics in S-scheme photocatalytic systems
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作者 Meng Li Xuanhua Li Jahan B.Ghasemi 《Chinese Journal of Catalysis》 2025年第6期12-15,共4页
Natural photosynthesis,the cornerstone of life on Earth,has long inspired sustainable chemistry by converting solar energy into chemical energy,thereby maintaining atmospheric balance and supporting biological product... Natural photosynthesis,the cornerstone of life on Earth,has long inspired sustainable chemistry by converting solar energy into chemical energy,thereby maintaining atmospheric balance and supporting biological productivity.Mimicking this natural process,photocatalysis has emerged as a promising strategy for harnessing solar energy to drive chemical reactions with minimal environmental impact.This versatile approach finds applications in pollutant degradation,water purification,energy conversion,and organic synthesis.However,a major limitation of single-component photocatalysts is the rapid recombination of photogenerated charge carriers,significantly reducing their efficiency. 展开更多
关键词 maintaining atmospheric balance converting solar energy chemical energythereby pollutant degradationwater photocatalytic systems sustainable chemistry organic sy biological productivitymimicking charge migration dynamics
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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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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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Polygonal Fault Systems in the Zhongjiannan Basin of South China Sea:Geometry,Evolution and Implications
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作者 HU Shouxiang ZHAO Fang 《Journal of Ocean University of China》 2026年第1期184-196,共13页
Polygonal fault systems(PFS),characterized by multi-directional fault patterns within layered sequences,are well-documented features in global continental margin basins.While the geometry and formation mechanisms of P... Polygonal fault systems(PFS),characterized by multi-directional fault patterns within layered sequences,are well-documented features in global continental margin basins.While the geometry and formation mechanisms of PFS have been extensively studied in the northern South China Sea,the PFS in the Zhongjiannan Basin(western South China Sea)remain relatively unexplored,with a lack of quantitative analysis regarding their propagation.This study addresses this gap by using high-resolution three-dimensional(3D)seismic data and conducting a quantitative fault analysis to thoroughly examine the planform,cross-sectional geometry,and evolution of PFS in the northern Zhongjiannan Basin.The absence of a dominant strike direction among these polygonal faults suggests that their evolution is not controlled by anisotropic stress.Our interpretation of seismic data,constrained by the spatial relationship among PFS,gullies,and pockmarks,indicates that PFS mainly developed within the Miocene strata,with their initiation occurring during the late Miocene.Furthermore,the PFS act as key conduits connecting gullies to pockmarks in this area.The formation and development of PFS may be primarily driven by thermally triggered processes within siliceous sediments.The necessary heat source is probably associated with the abundant submarine magmatism observed in the Zhongjiannan Basin.To reconstruct the regional geological history,a four-stage evolutionary model,incorporating the formation of PFS,is presented.This research significantly improves our understanding of the regional geological evolution of the Zhongjiannan Basin,providing critical insights into the initiation and development of PFS in the western South China Sea. 展开更多
关键词 South China Sea Zhongjiannan Basin polygonal faults layer-bound faults fluid migration GULLIES POCKMARK
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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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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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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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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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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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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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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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Small extracellular vesicles derived from hair follicle neural crest stem cells enhance perineurial cell proliferation and migration via the TGF-β/SMAD/HAS2 pathway
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作者 Yiming Huo Bing Xiao +8 位作者 Haojie Yu Yang Xu Jiachen Zheng Chao Huang Ling Wang Haiyan Lin Jiajun Xu Pengfei Yang Fang Liu 《Neural Regeneration Research》 2026年第5期2060-2072,共13页
Peripheral nerve defect repair is a complex process that involves multiple cell types;perineurial cells play a pivotal role.Hair follicle neural crest stem cells promote perineurial cell proliferation and migration vi... Peripheral nerve defect repair is a complex process that involves multiple cell types;perineurial cells play a pivotal role.Hair follicle neural crest stem cells promote perineurial cell proliferation and migration via paracrine signaling;however,their clinical applications are limited by potential risks such as tumorigenesis and xenogeneic immune rejection,which are similar to the risks associated with other stem cell transplantations.The present study therefore focuses on small extracellular vesicles derived from hair follicle neural crest stem cells,which preserve the bioactive properties of the parent cells while avoiding the transplantation-associated risks.In vitro,small extracellular vesicles derived from hair follicle neural crest stem cells significantly enhanced the proliferation,migration,tube formation,and barrier function of perineurial cells,and subsequently upregulated the expression of tight junction proteins.Furthermore,in a rat model of sciatic nerve defects bridged with silicon tubes,treatment with small extracellular vesicles derived from hair follicle neural crest stem cells resulted in higher tight junction protein expression in perineurial cells,thus facilitating neural tissue regeneration.At 10 weeks post-surgery,rats treated with small extracellular vesicles derived from hair follicle neural crest stem cells exhibited improved nerve function recovery and reduced muscle atrophy.Transcriptomic and micro RNA analyses revealed that small extracellular vesicles derived from hair follicle neural crest stem cells deliver mi R-21-5p,which inhibits mothers against decapentaplegic homolog 7 expression,thereby activating the transforming growth factor-β/mothers against decapentaplegic homolog signaling pathway and upregulating hyaluronan synthase 2 expression,and further enhancing tight junction protein expression.Together,our findings indicate that small extracellular vesicles derived from hair follicle neural crest stem cells promote the proliferation,migration,and tight junction protein formation of perineurial cells.These results provide new insights into peripheral nerve regeneration from the perspective of perineurial cells,and present a novel approach for the clinical treatment of peripheral nerve defects. 展开更多
关键词 hair follicle neural crest stem cells HAS2 migration miR-21-5p perineurial cells proliferation peripheral nerve injury SMAD7 small extracellular vesicles transforming growth factor-β/SMAD signaling pathway
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Migration and transfer of chromium in soil-vegetable system and associated health risks in vicinity of ferro-alloy manufactory 被引量:6
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作者 廖映平 王振兴 +3 位作者 杨志辉 柴立元 陈建群 袁平夫 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2011年第11期2520-2527,共8页
Study was carried out to analyze the distribution and migration patterns,soil-to-plant transfer and potential health risks of chromium in soil-vegetable system in areas near a ferro-alloy manufactory in Hunan province... Study was carried out to analyze the distribution and migration patterns,soil-to-plant transfer and potential health risks of chromium in soil-vegetable system in areas near a ferro-alloy manufactory in Hunan province.The results show that soils near sewer outlet,sewer channel and in control area are averaged 2 239.5,995.33 and 104.9 mg/kg,respectively.The total Cr has a relative accumulation in soil depth of 200-400 mm near the sewer outlet,mainly enriches in the surface layer(0-200 mm) near the sewer channel and decreases gradually in unpolluted soils.The differential concentration level of enrichment between layers is little.The results also indicate that the three vegetables of celery,lettuce and Chinese cabbage are able to convert the potentially toxic Cr(Ⅵ) species into the non-toxic Cr(Ⅲ) species,and the chromium contents in the edible parts of the vegetables are averaged 11.95 mg/kg.The transfer factors of the three vegetables follow the order:Chinese cabbage lettuce celery.The estimated total daily intake of chromium substantially exceeds the dietary allowable value,which may pose health risks to local population. 展开更多
关键词 heavy metal CHROMIUM migration transfer factor health risk soil VEGETABLE
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Effective migration system of coalbed methane reservoirs in the southern Qinshui Basin 被引量:2
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作者 WU CaiFang QIN Yong ZHOU LongGang 《Science China Earth Sciences》 SCIE EI CAS 2014年第12期2978-2984,共7页
Effective migration system of coalbed methane(CBM)reservoir,which was controlled by development degree and opening-closing degree of fractures,determines the permeability of coal reservoir and can be characterized by ... Effective migration system of coalbed methane(CBM)reservoir,which was controlled by development degree and opening-closing degree of fractures,determines the permeability of coal reservoir and can be characterized by the pore-fracture system in the extrinsic form.In this paper,based on coal matrix elastic self-regulating effect theory and coal reservoir combined elastic energy theory,the fracture opening-closing degree parameterΔand the fracture development degree parameterξare suggested for the quantitative study of the effective migration system of CBM reservoir in southern Qinshui Basin.Further,the control functions ofξandΔto CBM enrichment and high production are discussed.The results show that in present stage the area with highξvalue is located in Anze and Qinyuan,and then Zhengzhuang and Fangzhuang,where fracture development degree is high.The area with highΔvalue is located in Zhengzhuang and Fanzhuang,and then Anze and Qinyuan,indicating where coal matrix elastic self-regulating positive effect dominates and fractures tend to be open.Through the comprehensive analysis onξandΔ,it can be found that their best match area is located in Zhengzhuang and Fanzhuang,with high values for fracture development degree and opening-closing degree probably bringing about high fluid pressure and good permeability of reservoirs,which are advantageous to an abundant CBM production. 展开更多
关键词 CBM reservoirs effective migration system opening-closing degree of fracture development degree of fracture PERMEABILITY
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