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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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A-site doping enabled synergistic regulation of phase transition and electron spin state for improved performance of La_(0.6)Ca_(0.4)FeO_(3-δ)cathodes in solid oxide fuel cells
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作者 Na Lv Yumei Ma +1 位作者 Lina Su Ling Huang 《Nano Research》 2026年第1期589-597,共9页
Although intermediate temperature solid oxide fuel cells(IT-SOFCs)show great potential to address energy conversion challenges,the sluggish oxygen reduction reaction(ORR)kinetics of cathode materials has severely hind... Although intermediate temperature solid oxide fuel cells(IT-SOFCs)show great potential to address energy conversion challenges,the sluggish oxygen reduction reaction(ORR)kinetics of cathode materials has severely hindered extended applications.Herein,we have demonstrated that Bi^(3+)doping on the A-site synergistically regulates the phase transition and electron spin state in La_(0.3)Bi_(0.3)Ca_(0.4)FeO_(3-δ)(LBCF3)for improved performance.An orthorhombic to cubic phase transition occurred with Bi^(3+)doping increases oxygen vacancy concentration and thus increases oxygen ion migration capacity.Simultaneously,the change of Fe from low to medium electron spin state strengths O_(2)adsorption and improves catalytic performances.Consequently,a peak power density improvement up to 48%(from 1.21 to 1.79 W·cm^(-2))at 800℃ is realized in the anodesupported single cell using LBCF3 as cathode,which remains stable for over 270 h at 750℃. 展开更多
关键词 solid oxide fuel cells La_(0.6)Ca_(0.4)FeO_(3-δ) A-site modulation spin state transition oxygen reduction reaction(ORR)
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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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Temperature-dependent competition between dislocation motion and phase transition in CdTe 被引量:1
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作者 Jun Li Kun Luo Qi An 《Journal of Materials Science & Technology》 2025年第23期109-121,共13页
The plastic deformation of semiconductors,a process critical to their mechanical and electronic properties,involves various mechanisms such as dislocation motion and phase transition.Here,we systematically examined th... The plastic deformation of semiconductors,a process critical to their mechanical and electronic properties,involves various mechanisms such as dislocation motion and phase transition.Here,we systematically examined the temperature-dependent Peierls stress for 30°and 90°partial dislocations in cadmium telluride(CdTe),using a combination of molecular statics and molecular dynamics simulations with a machine-learning force field,as well as density functional theory simulations.Our findings reveal that the 0 K Peierls stresses for these partial dislocations in CdTe are relatively low,ranging from 0.52 GPa to 1.46 GPa,due to its significant ionic bonding characteristics.Notably,in the CdTe system containing either a 30°Cd-core or 90°Te-core partial dislocation,a phase transition from the zinc-blende phase to theβ-Sn-like phase is favored over dislocation motion.This suggests a competitive relationship between these two mechanisms,driven by the bonding characteristics within the dislocation core and the relatively low phase transition stress of∼1.00 GPa.Furthermore,we observed a general trend wherein the Peierls stress for partial dislocations in CdTe exhibits a temperature dependence,which decreases with increasing temperature,becoming lower than the phase transition stress at elevated temperatures.Consequently,the dominant deformation mechanism in CdTe shifts from solid-state phase transition at low temperatures to dislocation motion at high temperatures.This investigation uncovers a compelling interplay between dislocation motion and phase transition in the plastic deformation of CdTe,offering profound insights into the mechanical behavior and electronic performance of CdTe and other II-VI semiconductors. 展开更多
关键词 CDTE Peierls stress Dislocation motion Solid-state phase transition Machine-learning force field
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Medium-entropy configuration enabling reversible P2-OP4 phase transition in layered oxides for high-rate sodium-ion batteries 被引量:2
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作者 Fei-Fei Hong Xin Zhou +9 位作者 Hao Liu Gui-Lin Feng Xiao-Hong Liu Heng Zhang Wei-Feng Fan Bin Zhang Mei-Hua Zuo Wang-Yan Xing Ping Zhang Wei Xiang 《Rare Metals》 2025年第5期2997-3007,共11页
Layered transition metal oxides have emerged as promising cathode materials for sodium ion batteries.However,irreversible phase transitions cause structural distortion and cation rearrangement,leading to sluggish Na+d... Layered transition metal oxides have emerged as promising cathode materials for sodium ion batteries.However,irreversible phase transitions cause structural distortion and cation rearrangement,leading to sluggish Na+dynamics and rapid capacity decay.In this study,we propose a medium-entropy cathode by simultaneously introducing Fe,Mg,and Li dopants into a typical P2-type Na_(0.75)Ni_(0.25)Mn_(0.75)O_(2)cathode.The modified Na_(0.75)Ni_(0.2125)Mn_(0.6375)Fe_(0.05)Mg_(0.05)Li_(0.05)O_(2)cathode predominantly exhibits a main P2 phase(93.5%)with a minor O3 phase(6.5%).Through spectroscopy techniques and electrochemical investigations,we elucidate the redox mechanisms of Ni^(2+/3+/4+),Mn^(3+/4+),Fe^(3+/4+),and O_(2)-/O_(2)^(n-)during charging/discharging.The medium-entropy doping mitigates the detrimental P2-O_(2)phase transition at high-voltage,replacing it with a moderate and reversible structural evolution(P2-OP4),thereby enhancing structural stability.Consequently,the modified cathode exhibits a remarkable rate capacity of 108.4 mAh·g^(-1)at 10C,with a capacity retention of 99.0%after 200 cycles at 1C,82.5%after 500 cycles at 5C,and 76.7%after 600 cycles at 10C.Furthermore,it also demonstrates superior electrochemical performance at high cutoff voltage of 4.5 V and extreme temperature(55 and 0℃).This work offers solutions to critical challenges in sodium ion batteries cathode materials. 展开更多
关键词 Layered oxide cathode Sodium ion batteries Phase transition Medium-entropy P2/O3 biphasic structure
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Tectonic transition from the Paleo-Asian Ocean to the Paleo- Pacific Ocean: insights from volcano-sedimentary rocks in NE China 被引量:1
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作者 MENG Weihao WANG Hongyan ZHOU Jianbo 《Global Geology》 2025年第1期11-34,共24页
Since the Paleozoic,the tectonic evolution of northeastern Eurasia has been primarily influenced by the Paleo-Asian Ocean and the Paleo-Pacific tectonic domains.However,the spatial and temporal frameworks,as well as t... Since the Paleozoic,the tectonic evolution of northeastern Eurasia has been primarily influenced by the Paleo-Asian Ocean and the Paleo-Pacific tectonic domains.However,the spatial and temporal frameworks,as well as the timing of the tectonic transition between these two oceanic domains,remain unclear.For addressing these issues,we present petrological,geochronological,and geochemical data for andesite and sandstone samples from the Seluohe Group along the Jilin-Yanji Suture between the Jiamusi-Khanka Block and the North China Craton.The geochemical results indicate that the andesite sample is high-Mg andesite.Its magma source was generated by the metasomatized mantle wedge influenced by fluids derived from the subducted slab in a continental island arc setting.The high-Mg andesite gives the crystallization ages of Early Triassic(249±3 Ma).The sandstone is immature greywacke with a maximum depositional age of Early Triassic(247±1 Ma),and its sediments primarily originate from concurrent magmatic rocks within a juvenile continental arc.Based on our new findings,we propose that the Seluohe Group represents an Early Triassic volcanic-sedimentary association with continental island arc characteristics associated with the southwestward subduction of the Heilongjiang Ocean.We identified a sedimentary basin intimately associated with one or more continental arcs along the northeastern edge of the North China Craton.We suggest that the southwestward subduction of the Jilin-Heilongjiang Ocean in the Early Mesozoic accounts for this continental arc setting.There is a distinct temporal gap between the closure of the Paleo-Asian Ocean(ca.260 Ma)and the onset of Paleo-Pacific plate subduction(234–220 Ma),which is essentially coeval with the southwestward subduction of the Jilin-Heilongjiang Ocean between 255 Ma and 239 Ma. 展开更多
关键词 High-Mg andesite sedimentary basin Early Mesozoic Jilin-Heilongjiang Ocean tectonic transition in northeastern Eurasia
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A novel W-band substrate integrated microstrip to ultra-thin cavity filter transition
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作者 CAO Yi TANG Xiao-Hong +1 位作者 LIU Yong CAI Zong-Qi 《红外与毫米波学报》 北大核心 2025年第4期540-545,共6页
A novel substrate integrated microstrip to ultra-thin cavity filter transition operating in the W-band is proposed in this letter.The structure is a new method of connecting microstrip circuits and waveguide filters,a... A novel substrate integrated microstrip to ultra-thin cavity filter transition operating in the W-band is proposed in this letter.The structure is a new method of connecting microstrip circuits and waveguide filters,and this new structure enables a planar integrated transition from microstrip lines to ultra-thin cavity filters,thereby reducing the size of the transition structure and achieving miniaturization.The structure includes a conventional tapered microstrip transition structure,which guides the electromagnetic field from the microstrip line to the reduced-height dielectric-filled waveguide,and an air-filled matching cavity which is placed between the dielectric-filled waveguide and the ultra-thin cavity filter.The heights of the microstrip line,the dielectric-filled waveguide and the ultra-thin cavity filter are the same,enabling seamless integration within a planar radio-frequency(RF)circuit.To facilitate testing,mature finline transition structures are integrated at both ends of the microstrip line during fabrications.The simulation results of the fabricated microstrip to ultra-thin cavity filter transition with the finline transition structure,with a passband of 91.5-96.5 GHz,has an insertion loss of less than 1.9 dB and a return loss lower than-20 dB.And the whole structure has also been measured which achieves an insertion loss less than 2.6 dB and a return loss lower than-15 dB within the filter's passband,including the additional insertion loss introduced by the finline transitions.Finally,a W-band compact up-conversion module is designed,and the test results show that after using the proposed structure,the module achieves 95 dBc suppression of the 84 GHz local oscillator.It is also demonstrated that the structure proposed in this letter achieves miniaturization of the system integration without compromising the filter performance. 展开更多
关键词 transition ultra-thin cavity filter planar W-BAND MINIATURIZATION
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Perception of Senior Nurses regarding the Transition of Newly Graduated Nurses at Colonial War Memorial Hospital, Fiji
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作者 Samsun Ayub Laisa Tikomaimaleya Vani Rainima 《Open Journal of Nursing》 2025年第1期30-44,共15页
Introduction and Background: Registered nurses’ transit to the clinical placement areas after completing a three-year Bachelor of Nursing training. They should be supported by nurse leaders and nurse educators;to gai... Introduction and Background: Registered nurses’ transit to the clinical placement areas after completing a three-year Bachelor of Nursing training. They should be supported by nurse leaders and nurse educators;to gain confidence and the ability to perform critical care nursing, deal with high patient numbers, the ability to work independently and manage relationships with providers, families and the interprofessional team. Methods: A qualitative research design was employed to explore two important aspects of nursing professionalism. Firstly, the sentiments of senior registered nurses about professional mentorship of newly graduated nurses NGNs. Secondly the strategies employed by senior nurses to assist the transition of NGNs to professional nursing. Two nurse unit managers (NUM) participated as key informants. Results: Two themes will be discussed from the pilot study: Responsibilities and challenges faced by senior nurses while they supervise (NGNs) in their wards. Senior nurses’ workload and responsibilities fully occupy them during the days’ work, leaving very little time to spend supervising the NGNs. The challenges faced by senior nurses are those of restricted time, no proper resources, and mentoring manuals to guide the senior nurses. Discussion: The results of the pilot study present the challenges of senior nurses in supervising and training NGNs during transition, as they must complete the administrative tasks, finalizing rosters, and have direct patient contact. They usually face challenges while supervising the NGNs, sometimes leaving them to work on their own where the NGN is prone to make mistakes during patient care. Conclusion: Support and supervision are key to a successful transition, but senior nurses face difficulties, and challenges in many forms, there are no mentors available for the NGNs in any ward at the CWM Hospital while they train and supervise them during transitions. SNs take up a lot of responsibilities and provide support and supervision to NGNs. Some NGNs have undesirable attitudes that hinder the learning and teaching process. They also acknowledge that NGNs also need to play their role in learning to adapt to the new clinical environment with various challenges they face themselves. 展开更多
关键词 Experiences WORKLOAD PRECEPTORSHIP MENTORING transition
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M2 macrophages-derived exosomes for osteonecrosis of femoral head treatment:modulating neutrophil extracellular traps formation and endothelial phenotype transition 被引量:2
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作者 Guanzhi Liu Ruomu Cao +5 位作者 Qimeng Liu Heng Li Peng Yan Kunzheng Wang Run Tian Pei Yang 《Bone Research》 2025年第4期855-865,共11页
Exosomes have shown good potential in ischemic injury disease treatments.However,evidence about their effect and molecular mechanisms in osteonecrosis of femoral head(ONFH)treatment is still limited.Here,we revealed t... Exosomes have shown good potential in ischemic injury disease treatments.However,evidence about their effect and molecular mechanisms in osteonecrosis of femoral head(ONFH)treatment is still limited.Here,we revealed the cell biology characters of ONFH osteonecrosis area bone tissue in single cell scale and thus identified a novel ONFH treatment approach based on M2 macrophages-derived exosomes(M2-Exos).We further show that M2-Exos are highly effective in the treatment of ONFH by modulating the phenotypes communication between neutrophil and endothelium including neutrophil extracellular traps formation and endothelial phenotype transition.Additionally,we identified that M2-Exos’therapeutic effect is attributed to the high content of miR-93-5p and constructed miR-93-5p overexpression model in vitro and in vivo based on lentivirus and adenoassociated virus respectively.Then we found miR-93-5p can not only reduce neutrophil extracellular traps formation but also improve angiogenic ability of endothelial cells.These results provided a new theoretical basis for the clinical application of ONFH therapeutic exosomes. 展开更多
关键词 modulating phenotypes comm cell biology characters ischemic injury disease miR p osteonecrosis femoral neutrophil extracellular traps macrophages derived exosomes endothelial phenotype transition
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RGS4 promotes the progression of gastric cancer through the focal adhesion kinase/phosphatidyl-inositol-3-kinase/protein kinase B pathway and epithelial-mesenchymal transition
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作者 Peng-Yu Chen Pei-Yao Wang +7 位作者 Bang Liu Yang-Pu Jia Zhao-Xiong Zhang Xin Liu Dao-Han Wang Yong-Jia Yan Wei-Hua Fu Feng Zhu 《World Journal of Gastroenterology》 SCIE CAS 2025年第2期113-127,共15页
BACKGROUND Regulator of G protein signaling(RGS)proteins participate in tumor formation and metastasis by acting on theα-subunit of heterotrimeric G proteins.The speci-fic effect of RGS,particularly RGS4,on the progr... BACKGROUND Regulator of G protein signaling(RGS)proteins participate in tumor formation and metastasis by acting on theα-subunit of heterotrimeric G proteins.The speci-fic effect of RGS,particularly RGS4,on the progression of gastric cancer(GC)is not yet clear.AIM To explore the role and underlying mechanisms of action of RGS4 in GC develop-ment.METHODS The prognostic significance of RGS4 in GC was analyzed using bioinformatics based public databases and verified by immunohistochemistry and quantitative polymerase chain reaction in 90 patients with GC.Function assays were employed to assess the carcinogenic impact of RGS4,and the mechanism of its possible influence was detected by western blot analysis.A nude mouse xenograft model was established to study the effects of RGS4 on GC growth in vitro.RESULTS RGS4 was highly expressed in GC tissues compared with matched adjacent normal tissues.Elevated RGS4 expression was correlated with increased tumor-node-metastasis stage,increased tumor grade as well as poorer overall survival in patients with GC.Cell experiments demonstrated that RGS4 knockdown suppressed GC cell proliferation,migration and invasion.Similarly,xenograft experiments confirmed that RGS4 silencing significantly inhibited tumor growth.Moreover,RGS4 knockdown resulted in reduced phosphorylation levels of focal adhesion kinase,phosphatidyl-inositol-3-kinase,and protein kinase B,decreased vimentin and N-cadherin,and elevated E-cadherin.CONCLUSION High RGS4 expression in GC indicates a worse prognosis and RGS4 is a prognostic marker.RGS4 influences tumor progression via the focal adhesion kinase/phosphatidyl-inositol-3-kinase/protein kinase B pathway and epithelial-mesenchymal transition. 展开更多
关键词 Gastric cancer PROGNOSIS Regulator of G protein signaling 4 Focal adhesion kinase Epithelial-mesenchymal transition
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Characteristics of the Epidemiological Transition from 1990 to 2020 in Côte d’Ivoire
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作者 Guillaume Okoubo Daniel Kouadio Ekra +1 位作者 Ekissi Orsot Tetchi Calixte Guehi 《Open Journal of Epidemiology》 2025年第1期76-87,共12页
Background: Since it was theorised by Abdel Omran in 1971, the epidemiological transition has been well documented in Latin America, Asia and even increasingly in Africa south of the Sahara. According to this theory, ... Background: Since it was theorised by Abdel Omran in 1971, the epidemiological transition has been well documented in Latin America, Asia and even increasingly in Africa south of the Sahara. According to this theory, sub-Saharan Africa is in the first phase of development corresponding to the “age of plague and famine”. Given the health statistics currently available, more and more low- and middle-income countries, including those in sub-Saharan Africa, are experiencing an increase in mortality and the economic impact associated with non-communicable diseases. Côte d’Ivoire is one of the countries in sub-Saharan Africa where non-communicable diseases are currently on the rise. Despite the significant changes observed over the last decades, few studies have been carried out on the epidemiological transition in Côte d’Ivoire. It therefore seemed necessary to examine the changes in patterns of disease occurrence and causes of death in Côte d’Ivoire. Objectives: This work aimed to determine the reality of the epidemiological transition in Côte d’Ivoire and characterize its facies from 1990 to 2020. Methods: A literature review was carried out using PubMed, Medline, Google Scholar, Google, institutional websites (WHO, World Bank), university library websites and institutional reports from Côte d’Ivoire. The indicators sought were mortality, morbidity, life expectancy and fertility. Results: Mortality fell overall from 13.88‰ to 9.70‰, with variations linked to cyclical situations. Life expectancy rose by 52.6 to 59.03 years, although it is still below 60. Fertility has fallen from 6.3 to 4.5 children. There is a general downward trend in morbidity due to communicable diseases between 2009 and 2019, followed by an increase in non-communicable diseases. Conclusion: Côte d’Ivoire is undergoing an original and complex epidemiological transition that needs to be taken into account in health policies and strategies. 展开更多
关键词 Epidemiological transition Omran’s Theory of Epidemiological transition Communicable Diseases Non-Communicable Diseases Côte d’Ivoire
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Bearing Fault Diagnosis Based on the Markov Transition Field and SE-IShufflenetV2 Model
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作者 Chaozhi Cai Tiexin Xu +1 位作者 Jianhua Ren Yingfang Xue 《Structural Durability & Health Monitoring》 EI 2025年第1期125-144,共20页
A bearing fault diagnosis method based on the Markov transitionfield(MTF)and SEnet(SE)-IShufflenetV2 model is proposed in this paper due to the problems of complex working conditions,low fault diagnosis accuracy,and poo... A bearing fault diagnosis method based on the Markov transitionfield(MTF)and SEnet(SE)-IShufflenetV2 model is proposed in this paper due to the problems of complex working conditions,low fault diagnosis accuracy,and poor generalization of rolling bearing.Firstly,MTF is used to encode one-dimensional time series vibration sig-nals and convert them into time-dependent and unique two-dimensional feature images.Then,the generated two-dimensional dataset is fed into the SE-IShufflenetV2 model for training to achieve fault feature extraction and classification.This paper selects the bearing fault datasets from Case Western Reserve University and Paderborn University to experimentally verify the effectiveness and superiority of the proposed method.The generalization performance of the proposed method is tested under the variable load condition and different signal-to-noise ratios(SNRs).The experimental results show that the average accuracy of the proposed method under different working conditions is 99.2%without adding noise.The accuracy under different working conditions from 0 to 1 HP is 100%.When the SNR is 0 dB,the average accuracy of the proposed method can still reach 98.7%under varying working conditions.Therefore,the bearing fault diagnosis method proposed in this paper is characterized by high accuracy,strong anti-noise ability,and generalization.Moreover,the proposed method can also overcome the influence of variable working conditions on diagnosis accuracy,providing method support for the accurate diagnosis of bearing faults under strong noise and variable working conditions. 展开更多
关键词 Bearings Markov transitionfield SE-IShufflenetV2
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Metabolic landscape of human alveolar type II epithelial cells undergoing epithelial-mesenchymal transition induced directly by silica exposure 被引量:1
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作者 Jin Sun Na Zhao +8 位作者 Ruijia Zhang Yizheng Li Tiantian Yu Qiying Nong Li Lin Xubin Yang Tiangang Luan Baowei Chen Yongshun Huang 《Journal of Environmental Sciences》 2025年第3期676-687,共12页
Epithelial-mesenchymal transition(EMT)plays an irreplaceable role in the development of silicosis.However,molecular mechanisms of EMT induced by silica exposure still remain to be addressed.Herein,metabolic profiles o... Epithelial-mesenchymal transition(EMT)plays an irreplaceable role in the development of silicosis.However,molecular mechanisms of EMT induced by silica exposure still remain to be addressed.Herein,metabolic profiles of human alveolar type II epithelial cells(A549 cells)exposed directly to silica were characterized using non-targeted metabolomic approaches.A total of 84 differential metabolites(DMs)were identified in silica-treated A549 cells undergoing EMT,which were mainly enriched in metabolisms of amino acids(e.g.,glutamate,alanine,aspartate),purine metabolism,glycolysis,etc.The number of DMs identified in the A549 cells obviously increased with the elevated exposure concentration of silica.Remarkably,glutamine catabolism was significantly promoted in the silica-treated A549 cells,and the levels of related metabolites(e.g.,succinate)and enzymes(e.g.,α-ketoglutarate(α-KG)dehydrogenase)were substantially up-regulated,with a preference toα-KG pathway.Supplementation of glutamine into the cell culture could substantially enhance the expression levels of both EMT-related markers and Snail(zinc finger transcription factor).Our results suggest that the EMT of human alveolar epithelial cells directly induced by silica can be essential to the development of silicosis. 展开更多
关键词 Silica exposure Human alveolar type II epithelial cells(ATII cells) Epithelial-mesenchymal transition(EMT) Metabolomics GLUTAMINE
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