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High-Magnetic-Field-Induced First-Order Magnetic Transition and Tricritical Phenomenon in Antiferromagnetic Semimetal NdSb
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作者 Jun Zhao Azizur Rahman +7 位作者 Wei Liu Langsheng Ling Yuyan Han Chuanying Xi Li Pi Zhe Qu Hao Gao Lei Zhang 《Chinese Physics Letters》 2025年第2期125-131,共7页
The antiferromagnetic(AFM)semimetal NdSb is well known for the interplay between its exotic magnetism and topological properties.However,its magnetism remains poorly understood.In this study,we thoroughly investigated... The antiferromagnetic(AFM)semimetal NdSb is well known for the interplay between its exotic magnetism and topological properties.However,its magnetism remains poorly understood.In this study,we thoroughly investigated the magnetization of NdSb single crystals with a high magnetic field(H)of up to 30T applied in various directions.We found that the AFM phase is suppressed by a magnetic field of 9.41T when H‖[100]and 11.25T when H‖[110],whereas the suppression field ranges from 9.41 to 10.67T with a hysteresis of 1.26T when H‖[111].The magnetization of H‖[100],which is an easy direction with a typical magnetic transition,was studied in detail.The AFM phase with H‖[100]was suppressed at lower temperatures,disappearing at approximately 6.25 K.The critical exponents β=0.234(3),γ=0.824(6),and δ=4.90(6)were obtained for H‖[100],and aligned with a tricritical mean-field model.Analysis of the critical behavior suggests a fieldinduced tricritical phenomenon for H‖[100].An H-T phase diagram for an NdSb single crystal was constructed for H‖[100],revealing a field-induced first-order transition and a tricritical point(TCP)at T_(tr)=6.25K and H_(tr)=9.41 T.The clarification of the multiple magnetic phases and transitions in NdSb provides crucial insights into the correlation between its magnetism and topology. 展开更多
关键词 critical MAGNETIZATION transition
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Is There Kibble-Zurek Scaling of Topological Defects in First-Order Phase Transitions?
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作者 Fan Zhong 《Chinese Physics Letters》 2025年第3期10-15,共6页
Kibble-Zurek scaling is the scaling of the density of topological defects formed via the Kibble-Zurek mechanism with respect to the rate at which a system is cooled across a continuous phase transition.Recently,the de... Kibble-Zurek scaling is the scaling of the density of topological defects formed via the Kibble-Zurek mechanism with respect to the rate at which a system is cooled across a continuous phase transition.Recently,the density of the topological defects formed via the Kibble-Zurek mechanism was estimated for a system cooled through a first-order phase transition rather than conventional continuous transitions.Here we address the problem of whether such defects generated across a first-order phase transition exhibit Kibble-Zurek scaling similar to the case in continuous phase transitions.We show that any possible Kibble-Zurek scaling for the topological defects can only be a very rough approximation due to an intrinsic field responsible for the scaling.However,complete universal scaling for other properties does exist. 展开更多
关键词 transition SCALING TOPOLOGICAL
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Complete Universal Scaling of First-Order Phase Transitions in the Two-Dimensional Ising Model
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作者 Yuxiang Zhang Fan Zhong 《Chinese Physics Letters》 2025年第9期1-6,共6页
Phase transitions,as one of the most intriguing phenomena in nature,are divided into first-order phase transitions(FOPTs)and continuous ones in current classification.While the latter shows striking phenomena of scali... Phase transitions,as one of the most intriguing phenomena in nature,are divided into first-order phase transitions(FOPTs)and continuous ones in current classification.While the latter shows striking phenomena of scaling and universality,the former has recently also been demonstrated to exhibit scaling and universal behavior within a mesoscopic,coarse-grained Landau-Ginzburg theory.Here we apply this theory to a microscopic model-the paradigmatic Ising model,which undergoes FOPTs between two ordered phases below its critical temperature-and unambiguously demonstrate universal scaling behavior in such FOPTs.These results open the door for extending the theory to other microscopic FOPT systems and experimentally testing them to systematically uncover their scaling and universal behavior. 展开更多
关键词 first order phase transitions scaling universalitythe paradigmatic ising modelwhich two dimensional Ising model coarse grained Landau Ginzburg theory scaling universal behavior phase transitionsas universal scaling
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Electrospun Nanofibrous Transition Metal-based Bifunctional Electrocatalysts Toward Overall Water Splitting
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作者 YIN Yongting LU Xiaofeng 《高等学校化学学报》 北大核心 2026年第1期87-107,共21页
Electrochemical water splitting represents a sustainable technology for hydrogen(H_(2))production.However,its large-scale implementation is hindered by the high overpotentials required for both the cathodic hydrogen e... Electrochemical water splitting represents a sustainable technology for hydrogen(H_(2))production.However,its large-scale implementation is hindered by the high overpotentials required for both the cathodic hydrogen evolution reaction(HER)and the anodic oxygen evolution reaction(OER).Transition metal-based catalysts have garnered significant research interest as promising alternatives to noble-metal catalysts,owing to their low cost,tunable composition,and noble-metal-like catalytic activity.Nevertheless,systematic reviews on their application as bifunctional catalysts for overall water splitting(OWS)are still limited.This review comprehensively outlines the principal categories of bifunctional transition metal electrocatalysts derived from electrospun nanofibers(NFs),including metals,oxides,phosphides,sulfides,and carbides.Key strategies for enhancing their catalytic performance are systematically summarized,such as heterointerface engineering,heteroatom doping,metal-nonmetal-metal bridging architectures,and single-atom site design.Finally,current challenges and future research directions are discussed,aiming to provide insightful perspectives for the rational design of high-performance electrocatalysts for OWS. 展开更多
关键词 Electrospinning Nanofibers transition metal-based catalyst Overall water splitting Performance optimization
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Tracking a High-Tech Transition--How technology is powering Guangdong’s manufacturing transformation
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作者 HU FAN 《ChinAfrica》 2026年第1期30-32,共3页
The moment a media delegation from the Republic of the Congo arrived at the Othello Kitchenware Museum on 18 November 2025,they were greeted with a vivid show of Guangdong’s industrial strength.Standing before them w... The moment a media delegation from the Republic of the Congo arrived at the Othello Kitchenware Museum on 18 November 2025,they were greeted with a vivid show of Guangdong’s industrial strength.Standing before them was not a typical exhibition hall,but a building shaped like a gleaming stainless-steel cooking pot. 展开更多
关键词 othello kitchenware museum TECHNOLOGY industrial strength high tech transition guangdong manufacturing transformation
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Paeonol suppresses epithelial-mesenchymal transitiondriven posterior capsular opacification through activation of AMPK signaling
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作者 Qing Wang Qing-Yu Li +6 位作者 Jing Yang Jun Ma Ji-Hua Ping Zheng Wang Dai-Jie Wang Xia Hua Xiao-Yong Yuan 《International Journal of Ophthalmology(English edition)》 2026年第2期219-229,共11页
AIM:To determine whether paeonol(Pae),a naturally occurring phenolic compound,can serve as an effective pharmacological inhibitor of posterior capsular opacification(PCO).METHODS:A rat model of cataract surgery—induc... AIM:To determine whether paeonol(Pae),a naturally occurring phenolic compound,can serve as an effective pharmacological inhibitor of posterior capsular opacification(PCO).METHODS:A rat model of cataract surgery—induced PCO was established,and Pae was administered via anterior chamber injection to evaluate its preventive effect on capsular opacification and fibrotic remodeling.Histological and immunohistochemical analyses were performed to assess epithelial-mesenchymal transition(EMT)—related changes in lens epithelial cells(LECs).Ex vivo lens capsule cultures were employed to examine the expression of Vimentin and Zonula Occludens-1(ZO-1)by immunofluorescence and immunohistochemistry.In the human LEC line SRA01/04,EMT marker expression at both mRNA and protein levels was analyzed following transforming growth factor beta 2(TGF-β2)stimulation,with Pae treatment.Western blotting and immunofluorescence were used to investigate the effect of Pae on TGF-β/Smad signaling and AMP-activated protein kinase(AMPK)activation.Molecular docking was performed to predict Pae–AMPK binding,and rescue experiments with AMPK inhibition were conducted to validate the mechanistic pathway.RESULTS:Pae significantly reduced capsular opacification and fibrotic remodeling in the rat PCO model compared with controls.In LECs,Pae markedly suppressed TGF-β2–induced EMT,evidenced by decreased expression of mesenchymal markers,such as Vimentin,Fibronectin,Collagen 1A1,α-SMA and preserved epithelial junctional protein ZO-1.Mechanistically,Pae was predicted to directly interact with the catalytic pocket of AMPK,which was experimentally confirmed by enhanced AMPK phosphorylation and nuclear translocation(P<0.05).This activation disrupted canonical TGF-β/Smad signaling,leading to suppression of EMT.Rescue experiments using AMPK inhibition abrogated the anti-EMT effect of Pae,further validating the AMPK-dependent mechanism.CONCLUSION:Pae exerts a potent inhibitory effect on PCO formation by blocking EMT of LECs through direct activation of AMPK and subsequent disruption of TGF-β/Smad signaling. 展开更多
关键词 posterior capsular opacification PAEONOL epithelial-mesenchymal transition AMP-activated protein kinase transforming growth factor beta
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Anticipatory management for sustainable cultivated land transitions:Aligning multifunctional trajectories with adaptive zoning guidance
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作者 WU Junjie WANG Lingzhi +3 位作者 LONG Hualou LI Xinyao GUO Wenhua OMRANI Hichem 《Journal of Geographical Sciences》 2026年第1期16-44,共29页
Rapid regional population shifts and spatial polarization have heightened pressure on cultivated land—a critical resource demanding urgent attention amid ongoing urban-rural transition.This study selects Jiangsu prov... Rapid regional population shifts and spatial polarization have heightened pressure on cultivated land—a critical resource demanding urgent attention amid ongoing urban-rural transition.This study selects Jiangsu province,a national leader in both economic and agricultural development,as a case area to construct a multidimensional framework for assessing the recessive morphological characteristics of multifunctional cultivated land use.We examine temporal dynamics,spatial heterogeneity,and propose an integrated zoning strategy based on empirical analysis.The results reveal that:(1)The recessive morphology index shows a consistent upward trend,with structural breaks in 2007 and 2013,and a spatial shift from“higher in the east and lower in the west”to“higher in the south and lower in the north.”(2)Coordination among sub-dimensions of the index has steadily improved.(3)The index is expected to continue rising in the next decade,though at a slower pace.(4)To promote coordinated multidimensional land-use development,we recommend a policy framework that reinforces existing strengths,addresses weaknesses,and adapts zoning schemes to current spatial conditions.This research offers new insights into multifunctional cultivated land systems and underscores their role in enhancing human well-being,securing food supply,and supporting sustainable urban-rural integration. 展开更多
关键词 multifunctional cultivated land use recessive transition economic-social-ecological sub-dimension zoning management sustainable agro-urban systems future prediction Jiangsu province
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First-Order Quantum Phase Transition for Dicke Model Induced by Atom-Atom Interaction 被引量:2
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作者 赵秀琴 刘妮 梁九卿 《Communications in Theoretical Physics》 SCIE CAS CSCD 2017年第5期511-519,共9页
In this article, we use the spin coherent state transformation and the ground state variational method to theoretically calculate the ground function. In order to consider the influence of the atom-atom interaction on... In this article, we use the spin coherent state transformation and the ground state variational method to theoretically calculate the ground function. In order to consider the influence of the atom-atom interaction on the extended Dicke model's ground state properties, the mean photon number, the scaled atomic population and the average ground energy are displayed. Using the self-consistent field theory to solve the atom-atom interaction, we discover the system undergoes a first-order quantum phase transition from the normal phase to the superradiant phase, but a famous Dicke-type second-order quantum phase transition without the atom-atom interaction. Meanwhile, the atom-atom interaction makes the phase transition point shift to the lower atom-photon collective coupling strength. 展开更多
关键词 first-order quantum phase transition atom-atom interaction spin-coherent-state variational method
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First-order character of the displacive structural transition in BaWO_4
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作者 谭大勇 肖万生 +3 位作者 周微 陈鸣 熊小林 宋茂双 《Chinese Physics B》 SCIE EI CAS CSCD 2012年第8期365-373,共9页
Nearly all displacive transitions have been considered to be continuous or second order, and the rigid unit mode (RUM) provides a natural candidate for the soft mode. However, in-situ X-ray diffraction and Raman mea... Nearly all displacive transitions have been considered to be continuous or second order, and the rigid unit mode (RUM) provides a natural candidate for the soft mode. However, in-situ X-ray diffraction and Raman measurements show clearly the first-order evidences for the scheelite-to-fergusonite displacive transition in SaWO4: a 1.6% volume collapse, coexistence of phases, and hysteresis on release of pressure. Such first-order signatures are found to be the same as the soft modes in BaWO4, which indicates the scheelite-to-fergusonite displacive phase transition hides a deeper physical mechanism. By the refinement of atomic displacement parameters, we further show that the first-order character of this phase transition stems from a coupling of large compression of soft BaOs polyhedrons to the small displacive distortion of rigid WO4 tetrahedrons. Such a coupling will lead to a deeper physical insight in the phase transition of the common scheelite-structured compounds. 展开更多
关键词 BaWO4 pressure-induced phase transitions X-ray diffraction Raman scattering
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Influence of First-Order Phase Transition on the Single-Photon Spectra
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作者 AI Xiao-bai 《Chinese Physics Letters》 SCIE CAS CSCD 1997年第9期648-651,共4页
A dynamical like-compact-star structure model is presented to treat the first-order phase transition from quark-gluon plasma to hadronic matter.It is found that the influence of latent heat released in phase transitio... A dynamical like-compact-star structure model is presented to treat the first-order phase transition from quark-gluon plasma to hadronic matter.It is found that the influence of latent heat released in phase transition on the single-photon spectra is too evident to be ignored even with the conventional expansion scenario. 展开更多
关键词 transition transition QUARK
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Complete Universal Scaling in First-Order Phase Transitions
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作者 Fan Zhong 《Chinese Physics Letters》 SCIE EI CAS CSCD 2024年第10期8-13,共6页
Phase transitions and critical phenomena are among the most intriguing phenomena in nature and society.They are classified into first-order phase transitions(FOPTs)and continuous ones.While the latter shows marvelous ... Phase transitions and critical phenomena are among the most intriguing phenomena in nature and society.They are classified into first-order phase transitions(FOPTs)and continuous ones.While the latter shows marvelous phenomena of scaling and universality,whether the former behaves similarly is a long-standing controversial issue.Here we definitely demonstrate complete universal scaling in field driven FOPTs for Langevin equations in both zero and two spatial dimensions by rescaling all parameters and subtracting nonuniversal contributions with singular dimensions from an effective temperature and a special field according to an effective theory.This offers a perspective different from the usual nucleation and growth but conforming to continuous phase transitions to study FOPTs. 展开更多
关键词 theory. transitionS SCALING
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IS THE THERMAL DILEPTON SPECTRUM A SIGNATURE FOR DIAGNOSING FIRST-ORDER DETONATION QCD PHASE TRANSITION?
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作者 SHEN Jianguo QIU Xijun 《Chinese Physics Letters》 SCIE CAS CSCD 1989年第9期389-392,共4页
Detonation has two different scenarios:the Gyulassy's scenario and the Kapustafs one.The dilepton production rate in the Kapustafs scenario is calculated.Associated with the Gyulassyfs scenario,the peculiar proper... Detonation has two different scenarios:the Gyulassy's scenario and the Kapustafs one.The dilepton production rate in the Kapustafs scenario is calculated.Associated with the Gyulassyfs scenario,the peculiar property of the spectrum and its dynamical origin in the detonation phase transition are discussed and analyzed.Its spectrum is not a signature for diagnosing the detonation phase transition. 展开更多
关键词 transition. SPECTRUM SIGNATURE
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Correlation Between Additive Noises Induced First-Order Phase Transition in a Two-Mode Laser
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作者 LONG Quan CAO Li +1 位作者 WU Da-jin LI Zai-guang 《Chinese Physics Letters》 SCIE CAS CSCD 1996年第11期833-836,共4页
A phenomenological theory about the correlation between additive noises,in a two-mode laser arising from scattering of photons by the medium in the laser cavity is presented.It is applied to an inhomogeneously broaden... A phenomenological theory about the correlation between additive noises,in a two-mode laser arising from scattering of photons by the medium in the laser cavity is presented.It is applied to an inhomogeneously broadened two-mode ring laser.We have obtained an approximate expression for the steady-state intensity distribution,in which a first-order phase transition is found. 展开更多
关键词 transition ADDITIVE INHOMOGENEOUS
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First-order quantum phase transition and entanglement in the Jaynes-Cummings model with a squeezed light
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作者 汤椿琦 沈利托 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第7期262-267,共6页
We study the quantum phase transition and entanglement in the Jaynes-Cummings model with squeezed light,utilize a special transformation method to obtain the analytical ground state of the model within the near-resona... We study the quantum phase transition and entanglement in the Jaynes-Cummings model with squeezed light,utilize a special transformation method to obtain the analytical ground state of the model within the near-resonance regime,and numerically verify the validity of the analytical ground state.It is found that the ground state exhibits a first-order quantum phase transition at the critical point linearly induced by squeezed light,and the ground state entanglement reaches its maximum when the qubit-field coupling strength is large enough at the critical point. 展开更多
关键词 Jaynes-Cummings model quantum phase transition ENTANGLEMENT
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Arguing on Entropic and Enthalpic First-Order Phase Transitions in Strongly Interacting Matter
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作者 F. Wunderlich R. Yaresko B. Kämpfer 《Journal of Modern Physics》 2016年第8期852-862,共11页
The pattern of isentropes in the vicinity of a first-order phase transition is proposed as a key for a sub-classification. While the confinement-deconfinement transition, conjectured to set in beyond a critical end po... The pattern of isentropes in the vicinity of a first-order phase transition is proposed as a key for a sub-classification. While the confinement-deconfinement transition, conjectured to set in beyond a critical end point in the QCD phase diagram, is often related to an entropic transition and the apparently settled gas-liquid transition in nuclear matter is an enthalphic transition, the conceivable local isentropes w.r.t. “incoming” or “outgoing” serve as another useful guide for discussing possible implications, both in the presumed hydrodynamical expansion stage of heavy-ion collisions and the core-collapse of supernova explosions. Examples, such as the quark-meson model and two-phase models, are shown to distinguish concisely the different transitions. 展开更多
关键词 Entropic and Enthalpic Phase transitions Chiral Phase transition Isentropes Quark-Meson Model Linear Sigma Model with Linearized Fluctuations
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Energy Transition and Sustainable Development:Global Energy Market Analysis and Outlook for 2025 被引量:1
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作者 Zhou Jie 《China Oil & Gas》 2025年第1期I0001-I0004,共4页
China Oil&Gas,as a prominent academic journal in the energy industry,has been dedicated to advancing academic research and industrial development in the oil and gas energy field.As one of the authoritative media o... China Oil&Gas,as a prominent academic journal in the energy industry,has been dedicated to advancing academic research and industrial development in the oil and gas energy field.As one of the authoritative media outlets in the international energy sector,the magazine has long focused on the evolution of the global energy landscape and has organized and participated in several influential academic activities and research projects. 展开更多
关键词 SUSTAINABLE OUTLOOK transition
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Effect of macrophage- to- myofibroblast transition on silicosis 被引量:1
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作者 Fei Geng Jingrou Xu +12 位作者 Xichen Ren Ying Zhao Yuhao Cai Yaqian Li Fuyu Jin Tian Li Xuemin Gao Wenchen Cai Hong Xu Zhongqiu Wei Na Mao Ying Sun Fang Yang 《Animal Models and Experimental Medicine》 2025年第2期363-371,共9页
Background:The aim was to explore the effect of macrophage polarization and macrophage-to-myofibroblast transition(MMT)in silicosis.Methods:Male Wistar rats were divided into a control group and a silicosis group deve... Background:The aim was to explore the effect of macrophage polarization and macrophage-to-myofibroblast transition(MMT)in silicosis.Methods:Male Wistar rats were divided into a control group and a silicosis group developed using a HOPE MED 8050 dynamic automatic dusting system.Murine mac-rophage MH-S cells were randomly divided into a control group and an SiO_(2) group.The pathological changes in lung tissue were observed using hematoxylin and eosin(HE)and Van Gieson(VG)staining.The distribution and location of macrophage marker(F4/80),M1 macrophage marker(iNOS),M2 macrophage marker(CD206),and myofibroblast marker(α-smooth muscle actin[α-SMA])were detected using immu-nohistochemical and immunofluorescent staining.The expression changes in iNOS,Arg,α-SMA,vimentin,and type I collagen(Col I)were measured using Western blot.Results:The results of HE and VG staining showed obvious silicon nodule formation and the distribution of thick collagen fibers in the lung tissue of the silicosis group.Macrophage marker F4/80 increased gradually from 8 to 32 weeks after exposure to silica.Immunohistochemical and immunofluorescent staining results revealed that there were more iNOS-positive cells and some CD206-positive cells in the lung tissue of the silicosis group at 8 weeks.More CD206-positive cells were found in the silicon nodules of the lung tissues in the silicosis group at 32 weeks.Western blot analysis showed that the expressions of Inducible nitric oxide synthase and Arg protein in the lung tissues of the silicosis group were upregulated compared with those of the con-trol group.The results of immunofluorescence staining showed the co-expression of F4/80,α-SMA,and Col I,and CD206 andα-SMA were co-expressed in the lung tissue of the silicosis group.The extracted rat alveolar lavage fluid revealed F4/80+α-SMA+,CD206+α-SMA+,and F4/80+α-SMA+Col I+cells using immunofluorescence staining.Similar results were also found in MH-S cells induced by SiO_(2).Conclusions:The development of silicosis is accompanied by macrophage polarization and MMT. 展开更多
关键词 MACROPHAGE macrophage-to-myofibroblast transition SILICOSIS
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Anlotinib reverses osimertinib resistance by inhibiting epithelial-to-mesenchymal transition and angiogenesis in nonsmall cell lung cancer 被引量:1
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作者 Liting Lyu Xin Hua +5 位作者 Jiaxin Liu Sutong Zhan Qianqian Zhang Xiao Liang Jian Feng Yong Song 《Journal of Biomedical Research》 2025年第5期452-466,共15页
In the present study,we aimed to investigate whether anlotinib reverses osimertinib resistance by inhibiting the formation of epithelial-mesenchymal transition(EMT)and angiogenesis.In a clinical case,anlotinib reverse... In the present study,we aimed to investigate whether anlotinib reverses osimertinib resistance by inhibiting the formation of epithelial-mesenchymal transition(EMT)and angiogenesis.In a clinical case,anlotinib reversed osimertinib resistance in non-small cell lung cancer(NSCLC).Therefore,we performed immunohistochemical analyses on tumor tissues from three NSCLC patients with osimertinib resistance to analyze alterations in the expression levels of EMT markers and vascular endothelial growth factor A(VEGFA)before and after the development of osimertinib resistance.The results revealed the downregulation of E-cadherin,coupled with the upregulation of vimentin and VEGFA in tumor tissues of patients exhibiting osimertinib resistance,compared with those in tissues from patients before receiving osimertinib.Subsequently,we established osimertinib-resistant(Osi-R)cell lines and found that the Osi-R cells acquired EMT features.Next,we analyzed the synergistic effects of the combination therapy to verify whether anlotinib could reverse osimertinib resistance by inhibiting EMT.The expression levels of VEGFA and tube formation were analyzed in the combination group in vitro.Finally,we determined the reversal of osimertinib resistance by the combination of osimertinib and anlotinib in vivo using 20 nude mice.The combined treatment of osimertinib and anlotinib effectively prevented the metastasis of Osi-R cells,inhibited tumor growth,exerted antitumor activity,and ultimately reversed osimertinib resistance in mice.The co-administration of osimertinib and anlotinib demonstrated synergistic efficacy in inhibiting EMT and angiogenesis in three NSCLC patients,ultimately reversing osimertinib resistance. 展开更多
关键词 non-small cell lung cancer osimertinib anlotinib RESISTANCE epithelial-to-mesenchymal transition
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South Sudan: The Perils of Security Governance and the Treacherous Path to Democratic Transition 被引量:1
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作者 Luka Biong Deng Kuol 《International Relations and Diplomacy》 2025年第2期50-73,共24页
There is a growing recognition of the critical role of security governance in advancing democratic transition in the post-conflict environment.Despite such a recognition,the security sector reform concept has overshad... There is a growing recognition of the critical role of security governance in advancing democratic transition in the post-conflict environment.Despite such a recognition,the security sector reform concept has overshadowed the importance of the overarching strategic role of security governance in transition to democracy,particularly in Africa.This paper assesses the status and challenges facing security governance and how they thwarted the efforts to furthering the democratic transition in South Sudan.The paper shows a deterioration in security,safety and security governance outcomes since the independence of South Sudan in 2011 with such a trend unlikely to be abated in the near future without strategic interventions.Some of the challenges facing security governance in South Sudan include the legacies of some historical events including the“Big Tent Policy”,absence of strategic leadership,lack of overarching policy framework,impractical and tenuous security arrangements in the 2018 peace agreement,persistent postponement of the first elections,and dysfunctional justice sector.The paper provides some strategic and operational recommendations to improve security governance and advance democratic transition in South Sudan.These recommendations include formulation of an inclusive and people-centered national security policy,rigorous judicial reform,and early political agreement on new political infrastructure if conditions for holding the first national elections are not met in 2026. 展开更多
关键词 SECURITY GOVERNANCE South Sudan Peace Agreement POLICY JUSTICE REFORM Democratic transition
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Effects of supplementing bile acids on the production performance,fatty acid and bile acid composition,and gut microbiota in transition dairy cows 被引量:1
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作者 Lei Li Jiaxiao Li +7 位作者 Zhihui Liu Zihan Jin Mengyang Wang Ying Wu Zhihong Zhang Xinfeng Hou Junhu Yao Jun Zhang 《Journal of Animal Science and Biotechnology》 2025年第5期2152-2169,共18页
Background During the transition period,cows are prone to negative energy balance,which can lead to a decline in production performance and health in severe cases.In recent years,it has been discovered that bile acids... Background During the transition period,cows are prone to negative energy balance,which can lead to a decline in production performance and health in severe cases.In recent years,it has been discovered that bile acids(BAs)can act not only as fat emulsifiers but also as signaling molecules to regulate body metabolism.Although BAs have been used to some extent in monogastric and aquatic animals,their role in ruminants,particularly in transition cows,remains unclear.Therefore,this study aimed to determine the effects of BAs on the production performance,milk and plasma fatty acid and BA composition,and fecal microbiota in transition dairy cows.Results Forty-six healthy transition Holstein dairy cows with similar conditions were randomly divided into two groups and supplemented with 0 or 20 g/d of BAs from 21 d before the expected calving to 21 d after calving.The production performance was tracked until 60 d after calving.The results indicated that BA supplementation significantly improved postpartum milk fat content and yields as well as the yields of unsaturated fatty acids,monounsaturated fatty acids,and polyunsaturated fatty acids in milk.There was a significant increase in the concentration of triglyceride and the proportion of C≤16 fatty acids in the plasma of cows supplemented with BAs,while the concentration of β-hydroxybutyrate and the proportion of C>16 fatty acids in the plasma decreased significantly.BA supplementation significantly altered the composition of the fecal bacterial community and increased the relative abundance of bacteria beneficial for BA metabolism and transformation(Romboutsia,Clostridium sensu_stricto_6,and Clostridium sensu_stricto_1).Functional prediction analysis showed that the relative abundance of bile salt hydrolase,7 α-hydroxysteroid dehydrogenase,and BA inducible E as well as the pathways related to BA metabolism also significantly increased in cows supplemented BAs.In addition,BA supplementation significantly altered the composition of plasma and fecal BAs,particularly increasing circulating secondary BA concentration,which might induce the complete oxidation of fatty acids in the liver and further reduce the concentration of β-hydroxybutyrate.Conclusions These findings highlight the potential benefits of BA supplementation in improving milk yields and quality,as well as influencing metabolic pathways in transition dairy cows.Meanwhile,further studies are needed to elucidate the underlying mechanisms and explore the broader implications of these results by using more tissue samples. 展开更多
关键词 Bile acids Fatty acids Gut microbiota Production performance transition dairy cow
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