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
Fe_(3)Sn_(2),a ferromagnetic metal with a kagome lattice,serves as an ideal platform for exploring topological electronic states and Berry curvature due to its unique band structure.However,systematic reports on the t...Fe_(3)Sn_(2),a ferromagnetic metal with a kagome lattice,serves as an ideal platform for exploring topological electronic states and Berry curvature due to its unique band structure.However,systematic reports on the transport properties of Fe_(3)Sn_(2)nanosheets remain scarce.We present temperature-dependent transport property measurements of Fe_(3)Sn_(2)nanosheets synthesized via chemical vapor deposition on Si/SiO_(2)substrates.The samples exhibit a robust anomalous Hall effect from 40 K to 300 K,along with a magnetoresistance sign reversal at 40 K at high magnetic fields,indicating a spin reorientation from in-plane to out-of-plane.Notably,a sharp crossover in the dominant transport contribution from electrons to holes near 200 K is observed,accompanied by distinct anomalous Hall behaviors in the two regimes,indicating a temperature-induced Lifshitz transition within the multi-band system.This divergence is potentially linked to a topological reconstruction of the Fermi surface across the transition.Our findings highlight the tunability of topological transport in two-dimensional kagome magnets and provide new insights into the interplay between band topology,dimensionality and magnetic order.展开更多
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
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
Conventional Tb^(3+)-doped phosphors typically suffer from concentration quenching once the doping level exceeds a critical threshold.Consequently,the development of Tb^(3+)phosphors with intrinsic resistance to conce...Conventional Tb^(3+)-doped phosphors typically suffer from concentration quenching once the doping level exceeds a critical threshold.Consequently,the development of Tb^(3+)phosphors with intrinsic resistance to concentration quenching has become a key research focus.In this work,we successfully synthesized KBi(MoO_(4))_(2):x Tb^(3+)(x=0-100 at%)(denoted as KBM:x Tb^(3+))phosphors via a high-temperature solid-state reaction.Remarkably,no concentration quenching was observed across the entire doping range.This anti-quenching behavior originates from the large Tb^(3+)-Tb^(3+)interionic distance(>5Å)inherent to the quasi-layered crystal structure,which effectively suppresses multipole-interaction-mediated energy migration.At full Tb^(3+)substitution(x=100 at%),the material undergoes a structural phase transition from the monoclinic KBM phase to the triclinicα-KTb(MoO_(4))_(2)(α-KTM)phase.Theα-KTM phosphor exhibits excellent thermal stability(activation energy=0.6129 eV)and a single-exponential decay profile,whereas KBM:x Tb^(3+)(x<100%)display double-exponential decay behaviors,attributed to dual energy transfer pathways.These findings provide new insights into the luminescence mechanisms of high-concentration rare-earth-doped systems and offer guidance for designing nextgeneration anti-quenching phosphors.展开更多
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
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
In industrial control systems,such as power transmission facilities and water treatment plants,Programmable Logic Controllers(PLCs)can work consistently and stably over long periods if there are no faults.Black-box id...In industrial control systems,such as power transmission facilities and water treatment plants,Programmable Logic Controllers(PLCs)can work consistently and stably over long periods if there are no faults.Black-box identification aims to automatically construct Petri net models with the help of I/O signals from PLC devices only.The main challenge is how to convert the infinitely long PLC signals into an event sequence,which is the foundation for subsequent modeling.The current algorithms are confronted with a number of challenges,including an exponential increase in the number of transitions,high time complexity,and susceptibility to noisy signals.To solve these problems,this paper proposes a new method for converting PLC signals into a transition sequence.The method is based on the principles of Boolean absorption law,which filters out noise information in the I/O signals.Then firing functions representing input–output causality are constructed from the filtered signals.Finally,the original signal sequence is traversed to generate a transition sequence.The experimental results show that these methods can rapidly identify a transition sequence.Compared to traditional methods,the proposed algorithms have polynomial time complexity.展开更多
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
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
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
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
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
Columnar to equiaxial crystal transition(CET)is an important technological feature in many casting processes.This work investigated the CET during the solidification of Mg-Gd-Zn alloys by combining synchrotron radiati...Columnar to equiaxial crystal transition(CET)is an important technological feature in many casting processes.This work investigated the CET during the solidification of Mg-Gd-Zn alloys by combining synchrotron radiation in-situ imaging and phase-field method.Results show that the grain size,dendrite tip radius,and secondary dendrite arm spacing(SDAS)all exponentially decrease with an increase in cooling rate(Vc).The variation in the radius of the dendritic tip is similar to the prediction of the Hunt model,while the variation in the SDAS is close to the Bouchard-Kirkaldy model.It is worth noting that the CET is promoted by a decrease in the temperature gradient(G)and an increase in the cooling rate(Vc).In both equiaxed and columnar crystal regions,the dendrite tip growth rate and solid phase volume fraction increase with increasing G and Vc.In addition,the CET process has been predicted by simulation.The results are consistent with the predictions of the GTK model,which is important for the in-depth study of the dendrite morphology in different crystallization regions.In the final stage,the effects of different critical subcooling degrees and nucleation densities on the CET were explored.The results show that increasing the critical nucleation supercooling degree can inhibit the generation of equiaxial crystals,while increasing the nucleation density helps to promote the CET.展开更多
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
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
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
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
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
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
基金Supported by the National Natural Science Foundation of China(No.52273056)the Science and Technology Development Program of Jilin Province,China(No.YDZJ202501ZYTS305)。
文摘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.
基金Project supported by the National Key Research and Development Program of China(Grant Nos.2022YFA1403503,2022YFA1602802,2023YFA1607400,and 2024YFA1613200)Beijing Natural Science Foundation(Grant No.JQ23022)supported by the Synergetic Extreme Condition User Facility and the Innovation Program for Quantum Science and Technology(Grant No.2021ZD0302600)。
文摘Fe_(3)Sn_(2),a ferromagnetic metal with a kagome lattice,serves as an ideal platform for exploring topological electronic states and Berry curvature due to its unique band structure.However,systematic reports on the transport properties of Fe_(3)Sn_(2)nanosheets remain scarce.We present temperature-dependent transport property measurements of Fe_(3)Sn_(2)nanosheets synthesized via chemical vapor deposition on Si/SiO_(2)substrates.The samples exhibit a robust anomalous Hall effect from 40 K to 300 K,along with a magnetoresistance sign reversal at 40 K at high magnetic fields,indicating a spin reorientation from in-plane to out-of-plane.Notably,a sharp crossover in the dominant transport contribution from electrons to holes near 200 K is observed,accompanied by distinct anomalous Hall behaviors in the two regimes,indicating a temperature-induced Lifshitz transition within the multi-band system.This divergence is potentially linked to a topological reconstruction of the Fermi surface across the transition.Our findings highlight the tunability of topological transport in two-dimensional kagome magnets and provide new insights into the interplay between band topology,dimensionality and magnetic order.
文摘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.
基金Supported by the Projects of Medical and Health Technology Development Program in Shandong Province(No.202107021009)Shandong Provincial Traditional Chinese Medicine Science and Technology Project(No.M-2023118).
文摘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.
基金supported by the Natural Science Research Project of Anhui Province Education Department for Excellent Young Scholars(Grant No.2024AH030007)the National Natural Science Foundation of China(Grant No.52202001)。
文摘Conventional Tb^(3+)-doped phosphors typically suffer from concentration quenching once the doping level exceeds a critical threshold.Consequently,the development of Tb^(3+)phosphors with intrinsic resistance to concentration quenching has become a key research focus.In this work,we successfully synthesized KBi(MoO_(4))_(2):x Tb^(3+)(x=0-100 at%)(denoted as KBM:x Tb^(3+))phosphors via a high-temperature solid-state reaction.Remarkably,no concentration quenching was observed across the entire doping range.This anti-quenching behavior originates from the large Tb^(3+)-Tb^(3+)interionic distance(>5Å)inherent to the quasi-layered crystal structure,which effectively suppresses multipole-interaction-mediated energy migration.At full Tb^(3+)substitution(x=100 at%),the material undergoes a structural phase transition from the monoclinic KBM phase to the triclinicα-KTb(MoO_(4))_(2)(α-KTM)phase.Theα-KTM phosphor exhibits excellent thermal stability(activation energy=0.6129 eV)and a single-exponential decay profile,whereas KBM:x Tb^(3+)(x<100%)display double-exponential decay behaviors,attributed to dual energy transfer pathways.These findings provide new insights into the luminescence mechanisms of high-concentration rare-earth-doped systems and offer guidance for designing nextgeneration anti-quenching phosphors.
文摘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.
基金The National Natural Science Foundation of China(no.82204006)the Science and Technology of Project of Hebei Education Department(QN2022009)+1 种基金the Provincial Graduate Student Innovation Funding Project of Hebei Province(CXZZBS2022104)the National Natural Science Foundation of Hebei Province(H2020209292).
文摘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.
基金supported by the Science and Technology Planning Project of Fujian Province,China,under Grant No.2024H0014(2024H01010100).
文摘In industrial control systems,such as power transmission facilities and water treatment plants,Programmable Logic Controllers(PLCs)can work consistently and stably over long periods if there are no faults.Black-box identification aims to automatically construct Petri net models with the help of I/O signals from PLC devices only.The main challenge is how to convert the infinitely long PLC signals into an event sequence,which is the foundation for subsequent modeling.The current algorithms are confronted with a number of challenges,including an exponential increase in the number of transitions,high time complexity,and susceptibility to noisy signals.To solve these problems,this paper proposes a new method for converting PLC signals into a transition sequence.The method is based on the principles of Boolean absorption law,which filters out noise information in the I/O signals.Then firing functions representing input–output causality are constructed from the filtered signals.Finally,the original signal sequence is traversed to generate a transition sequence.The experimental results show that these methods can rapidly identify a transition sequence.Compared to traditional methods,the proposed algorithms have polynomial time complexity.
基金supported by the National Natural Science Foundation of China(Grant Nos.82172728,82370096).
文摘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.
文摘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.
基金supported by the National Center of Technology Innovation for Dairy(No.2024-JSGG-021)the National Natural Science Foundation of China(No.32102570)the Key Research and Development Project of Ningxia(No.2024BBF01006).
文摘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.
基金supported by the National Science Foundation(No.CMMI-2019459).
文摘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.
基金supported by the National Natural Science Foundation of China(No.21805018)by Sichuan Science and Technology Program(Nos.2022ZHCG0018,2023NSFSC0117 and 2023ZHCG0060)Yibin Science and Technology Program(No.2022JB005)and China Postdoctoral Science Foundation(No.2022M722704).
文摘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.
基金financially supported by the Postdoctoral Research Project of Henan Province(No.202101003)the Key Research Programs of Higher Education Institutions in Henan Province(Nos.24A450003,23A460016)+2 种基金the Henan Provincial Key Laboratory of Intelligent Manufacturing of Machinery and Equipment Open Subjects(No.IM202308)the Zhengzhou University of Light Industry Doctoral Research Initiation Fund(No.2019BSJJ005)the Henan Provincial Science and Technology Tackling Project(No.23A460016).
文摘Columnar to equiaxial crystal transition(CET)is an important technological feature in many casting processes.This work investigated the CET during the solidification of Mg-Gd-Zn alloys by combining synchrotron radiation in-situ imaging and phase-field method.Results show that the grain size,dendrite tip radius,and secondary dendrite arm spacing(SDAS)all exponentially decrease with an increase in cooling rate(Vc).The variation in the radius of the dendritic tip is similar to the prediction of the Hunt model,while the variation in the SDAS is close to the Bouchard-Kirkaldy model.It is worth noting that the CET is promoted by a decrease in the temperature gradient(G)and an increase in the cooling rate(Vc).In both equiaxed and columnar crystal regions,the dendrite tip growth rate and solid phase volume fraction increase with increasing G and Vc.In addition,the CET process has been predicted by simulation.The results are consistent with the predictions of the GTK model,which is important for the in-depth study of the dendrite morphology in different crystallization regions.In the final stage,the effects of different critical subcooling degrees and nucleation densities on the CET were explored.The results show that increasing the critical nucleation supercooling degree can inhibit the generation of equiaxial crystals,while increasing the nucleation density helps to promote the CET.
基金Supported by the National Natural Science Foundation of China Nos.42230303,42430305 and 42302236Graduate Innovation Fund of Jilin University Number:2024CX109.
文摘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.
基金Supported by the Fundamental Research Funds for the Central Universities(ZYGX2021J008)。
文摘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.
文摘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.
基金the support of the National Natural Science Foundation of China (Grant No.82272503)Natural Science Foundation of Zhejiang Province (Grant No. LQN25H060006)
文摘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.
基金Supported by the Fundamental Research Program of Shanxi Province,No.202203021222418Research Program of Shanxi Provincial Health Commission,No.2023061+2 种基金Fundamental Research Cooperation Program of Beijing-Tianjin-Hebei Region of Natural Science Foundation of Tianjin,No.22JCZXJC00140Tianjin Major Science and Technology Project,No.21ZXJBSY00110Tianjin Health and Science and Technology Project,No.TJWJ2024ZK001.
文摘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.
文摘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.