Bone resorption by osteoclasts is a critical step in bone remodeling,a process important for maintaining bone homeostasis and repairing injured bone.We previously identified a bone marrow mesenchymal subpopulation,mar...Bone resorption by osteoclasts is a critical step in bone remodeling,a process important for maintaining bone homeostasis and repairing injured bone.We previously identified a bone marrow mesenchymal subpopulation,marrow adipogenic lineage precursors(MALPs),and showed that its production of RANKL stimulates bone resorption in young mice using Adipoq-Cre.To exclude developmental defects and to investigate the role of MALPs-derived RANKL in adult bone,we generated inducible reporter mice(Adipoq-CreER Tomato)and RANKL deficient mice(Adipoq-CreER RANKLflox/flox,iCKO).Single cell-RNA sequencing data analysis and lineage tracing revealed that Adipoq+cells contain not only MALPs but also some mesenchymal progenitors capable of osteogenic differentiation.In situ hybridization showed that RANKL mRNA is only detected in MALPs,but not in osteogenic cells.RANKL deficiency in MALPs induced at 3 months of age rapidly increased trabecular bone mass in long bones as well as vertebrae due to diminished bone resorption but had no effect on the cortical bone.Ovariectomy(OVX)induced trabecular bone loss at both sites.RANKL depletion either before OVX or at 6 weeks post OVX protected and restored trabecular bone mass.Furthermore,bone healing after drill-hole injury was delayed in iCKO mice.Together,our findings demonstrate that MALPs play a dominant role in controlling trabecular bone resorption and that RANKL from MALPs is essential for trabecular bone turnover in adult bone homeostasis,postmenopausal bone loss,and injury repair.展开更多
INTRODUCTION.On May 1st,2024,around 2:10 a.m.,a catastrophic collapse occurred along the Meilong Expressway near Meizhou City,Guangdong Province,China,at coordinates 24°29′24″N and 116°40′25″E.This colla...INTRODUCTION.On May 1st,2024,around 2:10 a.m.,a catastrophic collapse occurred along the Meilong Expressway near Meizhou City,Guangdong Province,China,at coordinates 24°29′24″N and 116°40′25″E.This collapse resulted in a pavement failure of approximately 17.9 m in length and covering an area of about 184.3 m^(2)(Chinanews,2024).展开更多
C/C-ZrC composites were prepared by precursor infiltration and pyrolysis using the organic zirconium as precursor.The conversion mechanisms of the precursors such as the thermal behavior,structural evolution,phase com...C/C-ZrC composites were prepared by precursor infiltration and pyrolysis using the organic zirconium as precursor.The conversion mechanisms of the precursors such as the thermal behavior,structural evolution,phase composition,microstructure,composition of the precursors and products were analyzed by thermal gravimetric analyzer,Fourier transform infrared spectrometer,X-ray diffraction and scanning electron microscope.The results indicate that the ZrC precursor transforms to inorganic ZrO2 from room temperature to 1200 ℃,then reduces to ZrC at 1600 ℃ through the carbothermal reduction reaction.The microstructure of the C/C-ZrC composites was also investigated.The composites exhibit an interesting structure,a coating composed of ZrC ceramic covers the exterior of the composite,and the ZrC ceramic is embedded in the pores of the matrix inside the composite.展开更多
Rockburst precursors are critical for disaster warning,yet the complexity of rockburst has hindered the identification of a unified precursor.Furthermore,the influence of loading rates(LRs)on acoustic emission(AE)prec...Rockburst precursors are critical for disaster warning,yet the complexity of rockburst has hindered the identification of a unified precursor.Furthermore,the influence of loading rates(LRs)on acoustic emission(AE)precursors in different rock types remains poorly understood.This study investigates the AE characteristics and early warning times of rockburst in slate and mica-schist under four LRs(0.05,0.15,0.25,and 0.5 MPa/s)using true triaxial unloading tests.The micro-crack state of the samples was evaluated using entropy,while critical slowing down(CSD)theory was applied to interpret AE precursors.The results reveal that as the LR increases,the rockburst stress of both rocks initially rises and then declines,with mica-schist exhibiting more severe damage and a higher dominance of tensile cracks.Notably,identifying rockburst precursors in mica-schist proved more challenging compared to slate.Among the methods tested,AE amplitude variance outperformed entropy in precursor identification.Additionally,the rockburst early warning time was found to be negatively correlated with the LR,with mica-schist consistently showing shorter warning times than slate.The CSD-derived precursor,due to its enhanced sensitivity,is recommended for early warning systems.These findings provide new insights into the role of LRs in rockburst dynamics and offer practical guidance for improving precursor identification and disaster mitigation strategies.展开更多
Polyacrylonitrile (PAN) precursor is a core precursor for the preparation of high-performance carbon fibers. Its unique chemical structure and physical properties directly contributes to the microstructure and mechani...Polyacrylonitrile (PAN) precursor is a core precursor for the preparation of high-performance carbon fibers. Its unique chemical structure and physical properties directly contributes to the microstructure and mechanical properties of carbon fibers, and therefore affect the overall performance of pultruded composites. This study systematically investigated the influence of PAN precursor properties on the degree of graphitization, surface morphology and mechanical properties of carbon fibers by regulating the molecular weight distribution, stretching ratio and impurity content of PAN precursor, and analyzed the mechanism of action of carbon fiber properties on the interfacial bonding strength and tensile/ bending properties of composites in combination with the pultrusion process. The results showed that when the filament stretchability was increased to 4.5 times, the axial orientation of carbon fibers increased by 18% and the tensile strength reached 520 MPa;Filaments with impurity content below 0.3% increase carbon fiber yield by 5.2% and interlaminar shear strength of composites by 23%. This study provides a theoretical basis for raw material screening and process optimization of high-performance carbon fibers and their composites.展开更多
The increasing sophistication of cyberattacks,coupled with the limitations of rule-based detection systems,underscores the urgent need for proactive and intelligent cybersecurity solutions.Traditional intrusion detect...The increasing sophistication of cyberattacks,coupled with the limitations of rule-based detection systems,underscores the urgent need for proactive and intelligent cybersecurity solutions.Traditional intrusion detection systems often struggle with detecting early-stage threats,particularly in dynamic environments such as IoT,SDNs,and cloud infrastructures.These systems are hindered by high false positive rates,poor adaptability to evolving threats,and reliance on large labeled datasets.To address these challenges,this paper introduces CyberGuard-X,an AI-driven framework designed to identify attack precursors—subtle indicators of malicious intent—before full-scale intrusions occur.CyberGuard-X integrates anomaly detection,time-series analysis,and multi-stage classification within a scalable architecture.The model leverages deep learning techniques such as autoencoders,LSTM networks,and Transformer layers,supported by semi-supervised learning to enhance detection of zero-day and rare threats.Extensive experiments on benchmark datasets(CICIDS2017,CSE-CIC-IDS2018,and UNSW-NB15)demonstrate strong results,including 96.1%accuracy,94.7%precision,and 95.3%recall,while achieving a zero-day detection rate of 84.5%.With an inference time of 12.8 ms and 34.5%latency reduction,the model supports real-time deployment in resource-constrained environments.CyberGuard-X not only surpasses baseline models like LSTM and Random Forest but also enhances proactive threat mitigation across diverse network settings.展开更多
This study investigates the instability characteristics of dynamic disasters resulting from disruption caused by extracting resources underground. Utilizing the split Hopkinson pressure bar (SHPB) system, the dynamic ...This study investigates the instability characteristics of dynamic disasters resulting from disruption caused by extracting resources underground. Utilizing the split Hopkinson pressure bar (SHPB) system, the dynamic response mechanism of coal energy evolution is examined, and the energy instability criterion is established. The validity of the instability criterion is explored from the standpoint of damage progression. The results demonstrate that the energy conversion mechanism undergoes a fundamental alternation under impact disturbance. Moreover, the energy release rate as well as the energy dissipation rate undergo comparable changes across distinct levels of impact disturbance. The distinction between the energy release rate and the energy dissipation rate (DRD) increases as coal mass deformation grows. Prior to coal facing instability and failure, the DRD experienced an inflection point followed by a sharp decrease. In conjunction with the discussion on the damage evolution, the physical and mechanical significance of DRD remains clear, which can essentially describe the whole impact loading process. The phenomenon that the inflection point appears and DRD subsequently suddenly decreases can be employed as the energy criterion prior to the failure of instability. Furthermore, this paper provides significant reference for the prediction of dynamic instability of coal under dynamic disturbance.展开更多
Metal composites produced through the liquid metal dealloying(LMD)process feature an advanced matrix-matrix composite structure,where two metallic materials form a continuous,three-dimensional interconnected network.T...Metal composites produced through the liquid metal dealloying(LMD)process feature an advanced matrix-matrix composite structure,where two metallic materials form a continuous,three-dimensional interconnected network.This study investigates the effects of Ti Cu precursor compositions on dealloying behavior and microstructural evolution in liquid Mg,using Ti_(50)Cu_(50)and Ti_(30)Cu_(70)precursors.The initial microstructure of the precursor significantly influences dealloying kinetics and phase transitions.The single-phase Ti_(50)Cu_(50)precursor exhibits a faster initial dealloying rate due to its homogeneous structure,yet complete dealloying requires 90 min.In contrast,the dualphase Ti_(30)Cu_(70)precursor achieves complete dealloying in 30 min,demonstrating the impact of a higher Cu concentration on accelerating the process kinetics.Additionally,the study explores the coarsening behavior and hardness variations during the LMD process,along with the microstructural characteristics of Mg-Ti composites fabricated from these two precursors.The findings highlight the critical role of precursor composition in tailoring the microstructure and properties of Mg-Ti composites produced through the LMD process,demonstrating its potential for advanced composite material manufacturing.展开更多
The current generation of ultrahigh temperature ceramic precursors typically encounters obstacles in achieving high ceramic yields(<40 wt.%)due to the challenges in integrating significant amounts of boron,which ha...The current generation of ultrahigh temperature ceramic precursors typically encounters obstacles in achieving high ceramic yields(<40 wt.%)due to the challenges in integrating significant amounts of boron,which hampers their conversion into boride-based ultrahigh temperature ceramics.To tackle these challenges,a serious of pioneering liquid multi-component hafnium-containing ceramic SiHfCB precursors(with different Hf/Si ratios)have been developed.These novel precursors are featured with stable molec-ular structure and high ceramic yield which were successfully created through a novel one-pot polymer-ization process.They present in liquid form and their structure is characterized by C-C bonds forming its main chain with branched chains of O-Si-O,Si-O-Hf,Si-O-B,and B-O-Hf which have untapped advantages including uniform component dispersion,and excellent fluidity.The ceramic yield of SiHfCB precursor with Hf/Si of 0.2 is remarkably up to 68.6 wt.%at 1500℃,and their Hf content exceeded 50 wt.%.Of particular interest,the pyrolyzed product HfB_(2)-SiC nanopowders derived from the SiHfCB precursor with Hf/Si of 0.2,consist of nanopowders in the 40-60 nm range with a density of 5.23 g cm^(−3).Remarkably,this material demonstrates exceptional performance in ultrahigh temperature oxygen-containing environ-ments at 2500℃,showing near-zero ablation with a linear ablation rate of just 2.5×10^(−4) mm s^(−1).Post-ablation analysis of the microstructure reveals that the formation of a lava-like HfO_(2) and HfO_(2)-SiO_(2) oxide layer effectively blocks oxygen penetration and provides excellent oxidation resistance.The inno-vative SiHfCB hafnium-containing ceramic precursor offers a groundbreaking solution for the preparation of lightweight ultrahigh-temperature ceramics.This development is poised to provide robust technical support for the use of ultrahigh temperature ceramics in non-ablative thermal protective systems,partic-ularly in the construction of hypersonic vehicles,where ultrahigh temperature resilience is crucial.展开更多
Objective To reveal the effects and potential mechanisms by which synaptic vesicle glycoprotein 2A(SV2A)influences the distribution of amyloid precursor protein(APP)in the trans-Golgi network(TGN),endolysosomal system...Objective To reveal the effects and potential mechanisms by which synaptic vesicle glycoprotein 2A(SV2A)influences the distribution of amyloid precursor protein(APP)in the trans-Golgi network(TGN),endolysosomal system,and cell membranes and to reveal the effects of SV2A on APP amyloid degradation.Methods Colocalization analysis of APP with specific tagged proteins in the TGN,ensolysosomal system,and cell membrane was performed to explore the effects of SV2A on the intracellular transport of APP.APP,β-site amyloid precursor protein cleaving enzyme 1(BACE1)expressions,and APP cleavage products levels were investigated to observe the effects of SV2A on APP amyloidogenic processing.Results APP localization was reduced in the TGN,early endosomes,late endosomes,and lysosomes,whereas it was increased in the recycling endosomes and cell membrane of SV2A-overexpressed neurons.Moreover,Arl5b(ADP-ribosylation factor 5b),a protein responsible for transporting APP from the TGN to early endosomes,was upregulated by SV2A.SV2A overexpression also decreased APP transport from the cell membrane to early endosomes by downregulating APP endocytosis.In addition,products of APP amyloid degradation,including sAPPβ,Aβ1-42,and Aβ1-40,were decreased in SV2A-overexpressed cells.Conclusion These results demonstrated that SV2A promotes APP transport from the TGN to early endosomes by upregulating Arl5b and promoting APP transport from early endosomes to recycling endosomes-cell membrane pathway,which slows APP amyloid degradation.展开更多
BACKGROUND Differential diagnosis among atypical hyperplasia(AH)(including reparative hyperplasia and intestinal metaplasia),low-grade dysplasia(LGD),high-grade dysplasia(HGD),and adenocarcinoma(AC)in gastric mucosal ...BACKGROUND Differential diagnosis among atypical hyperplasia(AH)(including reparative hyperplasia and intestinal metaplasia),low-grade dysplasia(LGD),high-grade dysplasia(HGD),and adenocarcinoma(AC)in gastric mucosal biopsies is challenging due to histomorphological overlaps,variability in pathological diagnosis consistency,and limited reproducibility.AIM To evaluate the diagnostic utility of P53,Ki67,P504S,and IMP3 in gastric cancer and its precancerous lesions,focusing on their effectiveness in distinguishing AH,LGD,HGD,and AC.METHODS From January 2018 to September 2020,a total of 185 gastric mucosal biopsy specimens were analyzed according to the pathological diagnostic criteria outlined in the World Health Organization Classification of Digestive System Tumors(2019).The specimens were categorized into four groups:AH,LGD,HGD,and AC.Immunohistochemistry was employed to assess the expression status of P53,Ki67,P504S,and IMP3.Intergroup comparisons were performed using theχ^(2)test or Fisher's exact probability test to compare the differences in immunohistochemical markers across the distinct lesion groups.RESULTS The expression rate of P504S was highest in the LGD group(53.3%,16/30),while IMP3 expression was highest in the AC group(41.9%,26/62),followed by the HGD group(33.3%).Significant differences in P504S and IMP3 expression levels were observed among the four lesion groups(P<0.001).Pairwise comparisons revealed statistically significant differences in P504S expression between the AH group and the LGD,HGD,and AC groups(P<0.001),as well as significant variations in IMP3 expression between the AH group and the HGD and AC groups,and between the LGD group and the HGD and AC groups(P<0.001).Additionally,significant correlations were found between P504S and the polarity expression pattern of Ki67,and between IMP3 and the mutation expression pattern of P53(P<0.001).The combined detection of P504S with Ki67 and IMP3 with P53 increased the diagnostic sensitivity for LGD and HGD/AC,respectively.CONCLUSION P504S is highly expressed in LGD and is associated with the Ki67“polarity”expression pattern.IMP3 is highly expressed in HGD/AC and is correlated with the P53 mutation expression pattern.The combined detection of P504S with Ki67 and IMP3 with P53 increased the diagnostic sensitivity for LGD and HGD/AC,respectively.The rational use of P504S,Ki67,IMP3,and p53 can help distinguish gastric cancer and precancerous lesions,improving the early cancer diagnosis rate.展开更多
Chronic cerebral hypoperfusion leads to white matter injury(WMI),which plays a significant role in contributing to vascular cognitive impairment.While 13-docosenamide is a type of fatty acid amide,it remains unclear w...Chronic cerebral hypoperfusion leads to white matter injury(WMI),which plays a significant role in contributing to vascular cognitive impairment.While 13-docosenamide is a type of fatty acid amide,it remains unclear whether it has therapeutic effects on chronic cerebral hypoperfusion.In this study,we conducted bilateral common carotid artery stenosis(BCAS)surgery to simulate chronic cerebral hypoperfusion-induced WMI and cognitive impairment.Our findings showed that 13-docosenamide alleviates WMI and cognitive impairment in BCAS mice.Mechanistically,13-docosenamide specifically binds to cannabinoid receptor 1(CNR1)in oligodendrocyte precursor cells(OPCs).This interaction results in an upregulation of ubiquitin-specific peptidase 33(USP33)-mediated CNR1 deubiquitination,subsequently increasing CNR1 protein expression,activating the phosphorylation of the AKT/mTOR pathway,and promoting the differentiation of OPCs.In conclusion,our study suggests that 13-docosenamide can ameliorate chronic cerebral hypoperfusion-induced WMI and cognitive impairment by enhancing OPC differentiation and could serve as a potential therapeutic drug.展开更多
Thorium dioxide(ThO_(2))fibers exhibit exceptional structural stability,low density and superior flexibility,coupled with a remarkably high melting point,positioning them as promising candidates for thermal protection...Thorium dioxide(ThO_(2))fibers exhibit exceptional structural stability,low density and superior flexibility,coupled with a remarkably high melting point,positioning them as promising candidates for thermal protection applications.Additionally,their commendable secondary processing characteristics enable the development of diverse composite materials when integrated with other materials,significantly broadening the potential utilization of ThO_(2)materials and thorium resources in industrial fields.In this work,the ThO_(2)fiber was fabricated by the sol-gel precursor method,and the precursor with good spinnability and excellent stability was synthesized for the first time.The ThO_(2)fiber with a mean diameter of 868 nm is both highly flexible and strong(max.tensile strength 2.21 MPa),capable of bending freely across a wide temperature range from-196℃(in liquid nitrogen)to 1200℃.Meanwhile,it exhibits excellent temperature stability and heat insulation properties.The ThO_(2)nanofiber membranes with layered structure have low density(32-37 mg·cm^(-3)),low thermal conductivity(27.3-30.1 mW·m^(-1)·K^(-1)@25℃).The ThO_(2)nanofiber membranes with 15 mm thickness can reduce the temperature from 1200 to 282℃and maintain a high aspect ratio and bendability after 1200℃@90 min.The results show that the ThO_(2)fiber can be used as a new kind of high-temperature resistant material.展开更多
Infiltration and activation of peripheral immune cells are critical in the progression of multiple sclerosis and its experimental animal model,experimental autoimmune encephalomyelitis(EAE).This study investigates the...Infiltration and activation of peripheral immune cells are critical in the progression of multiple sclerosis and its experimental animal model,experimental autoimmune encephalomyelitis(EAE).This study investigates the role of high mobility group box 1(HMGB1)in oligodendrocyte precursor cells(OPCs)in modulating pathogenic T cells infiltrating the central nervous system through the blood-brain barrier(BBB)by using OPC-specific HMGB1 knockout(KO)mice.We found that HMGB1 released from OPCs promotes BBB disruption,subsequently allowing increased immune cell infiltration.The migration of CD4+T cells isolated from EAE-induced mice was enhanced when co-cultured with OPCs compared to oligodendrocytes(OLs).OPC-specific HMGB1 KO mice exhibited lower BBB permeability and reduced immune cell infiltration into the CNS,leading to less damage to the myelin sheath and mitigated EAE progression.CD4+T cell migration was also reduced when co-cultured with HMGB1 knock-out OPCs.Our findings reveal that HMGB1 secretion from OPCs is crucial for regulating immune cell infiltration and provides insights into the immunomodulatory function of OPCs in autoimmune diseases.展开更多
Osteoclast-development patterns and their alterations across Ankylosing Spondylitis(AS)conditions are mysterious,making AS treatment difficult.Our study aims to clarify osteoclast-precursor(OCP)development patterns fr...Osteoclast-development patterns and their alterations across Ankylosing Spondylitis(AS)conditions are mysterious,making AS treatment difficult.Our study aims to clarify osteoclast-precursor(OCP)development patterns from monocytes and their variations under AS conditions.We performed single-cell transcriptomics in peripheral blood mononuclear cells(PBMCs)from healthy donors and AS patients in the early,aggravated and remission stages.After monocytic reclustering,OCP-development patterns and the alterations upon AS onset and different outcomes were revealed based on single-cell trajectory.The trajectories revealed two monocyte states with strong OCP features,and AS pathogenesis was characterized by their reduction.Ribosome synthesis was considered the essential function for the development towards OCP-featured states,and this function and its representative molecule,RPS17,showed a decreasing trend with AS onset and outcomes.Histology assessment showed that RPS17underexpression participated in AS inflammatory osteogenesis and ankylosing destruction.Conditional knockout of RPS17ameliorated ovariectomy-induced bone loss and enhanced osteoclastogenesis,and RPS17 overexpression improved the phenotype of AS-like mice.Importantly,local injection of RPS17-overexpressed monocytic OCPs markedly ameliorated the joint alterations of AS-like mice without promoting bone loss;this was associated with enhanced osteoclastogenesis adjacent to the articular surface and T-cell-suppressive property in monocytic OCPs.Overall,the evolution of monocytes towards OCP-lineage fate mainly depends on ribosome synthesis,and OCP-development disorder participates in AS lesions due to a reduction in RPS17-dependent ribosome synthesis.Notably,RPS17-overexpressed monocytic OCPs have translational potential in preventing and treating AS peripheral lesions.展开更多
To develop a melting-based larger-scale fabrication process for oxide dispersion strengthened(ODS)steel,this study proposed a method of zone melting with built-in precursor powder(ZMPP),followed by hot forging and agi...To develop a melting-based larger-scale fabrication process for oxide dispersion strengthened(ODS)steel,this study proposed a method of zone melting with built-in precursor powder(ZMPP),followed by hot forging and aging treatments.A 50 kg ingot was successfully prepared,highlighting the scalability of this innovative process.Microstructural analysis revealed a predominantly lath martensite matrix with a small amount of ferrite in the hot-forged ODS steel,without oxide particle aggregation.Aging at 750℃ resulted in the formation of sub-micron-sized Cr_(23)C_(6) particles at grain boundaries and martensitic lath interfaces,accompanied by a high-density(7.64×1023 m^(-3))nano-scale(~6 nm)Y-Si-O complex oxides after 25 h.Additionally,the hot-forged sample exhibited a high yield strength(871 MPa)but limited ductility(5.0%).Aging treatments led to an increase in ductility but a decrease in yield strength.Notably,prolonged aging maintained the strength level of steels while enhancing ductility,with a 23.3% total elongation observed after 25 h.The novel ZMPP method,preparing high-quality ODS steels with uniform microstructure and good mechanical properties,provided a new avenue for large-scale production of ODS steels.展开更多
The LiNi_(x)Co_(y)Mn_(1-x-y)O_(2)(NCM)cathode materials have emerged as critical components in lithium-ion batteries due to their high energy and power densities.The co-precipitation method is widely used in laborator...The LiNi_(x)Co_(y)Mn_(1-x-y)O_(2)(NCM)cathode materials have emerged as critical components in lithium-ion batteries due to their high energy and power densities.The co-precipitation method is widely used in laboratory and industry settings to optimize the crystallinity,grain morphology,particle size,and sphericity of precursor materials,directly affecting NCM battery performance.This review addresses the nucleation mechanism and the thermodynamic and kinetic reaction processes of co-precipitation.The comprehensive effects of key parameters on precursor physicochemical properties are also systematically interpreted.展开更多
Earthquakes can cause significant hazards,leading to loss of human life and property damage.In this study,we applied the masking empirical mode decomposition(EMD)to the Gyeongju earthquake(ML 5.8)in South Korea and th...Earthquakes can cause significant hazards,leading to loss of human life and property damage.In this study,we applied the masking empirical mode decomposition(EMD)to the Gyeongju earthquake(ML 5.8)in South Korea and the Abe Pura earthquake(ML 7.0)in Indonesia and then revealed that the 7th intrinsic mode function(IMF7),composed of waveforms with a period band of approximately 150 to 750 minutes.展开更多
Metal–insulator–semiconductor(MOS) capacitor is a key structure for high performance MOS field transistors(MOSFETs), requiring low leakage current, high breakdown voltage, and low interface states. In this paper, β...Metal–insulator–semiconductor(MOS) capacitor is a key structure for high performance MOS field transistors(MOSFETs), requiring low leakage current, high breakdown voltage, and low interface states. In this paper, β-Ga_(2)O_(3) MOS capacitors were fabricated with ALD deposited Al_(2)O_(3) using H_(2)O or ozone(O_(3)) as precursors. Compared with the Al_(2)O_(3) gate dielectric with H_(2)O as ALD precursor, the leakage current for the O_(3) precursor case is decreased by two orders of magnitude, while it keeps the same level at the fixed charges, interface state density, and border traps. The SIMS tests show that Al_(2)O_(3) with O_(3) as precursor contains more carbon impurities. The current transport mechanism analysis suggests that the C–H complex in Al_(2)O_(3) with O_(3) precursor serves as deep energy trap to reduce the leakage current. These results indicate that the Al_(2)O_(3)/β-Ga_(2)O_(3)MOS capacitor using the O_(3) precursor has a low leakage current and holds potential for application in β-Ga_(2)O_(3) MOSFETs.展开更多
The deposition of amyloid-beta is a pathological hallmark of Alzheimer＇s disease, Amyloid-beta is derived from amyloid precursor protein through sequential proteolytic cleavages by β-secretase （beta-site amyloid pr...The deposition of amyloid-beta is a pathological hallmark of Alzheimer＇s disease, Amyloid-beta is derived from amyloid precursor protein through sequential proteolytic cleavages by β-secretase （beta-site amyloid precursor protein-cleaving enzyme 1） and r-secretase. To further elucidate the roles of beta-site amyloid precursor protein-cleaving enzyme 1 in the development of AIzheimer＇s disease, a yeast two-hybrid system was used to screen a human embryonic brain cDNA library for proteins directly interacting with the intracellular domain of beta-site amyloid precursor protein-cleaving enzyme 1. A potential beta-site amyloid precursor protein-cleaving enzyme 1- interacting protein identified from the positive clones was divalent cation tolerance protein. Immunoprecipitation studies in the neuroblastoma cell line N2a showed that exogenous divalent cation tolerance protein interacts with endogenous beta-site amyloid precursor protein-cleaving enzyme 1. The overexpression of divalent cation tolerance protein did not affect beta-site amyloid precursor protein-cleaving enzyme 1 protein levels, but led to increased amyloid precursor protein levels in N2a/APP695 cells, with a concomitant reduction in the processing product amyloid precursor protein C-terminal fragment, indicating that divalent cation tolerance protein inhibits the processing of amyloid precursor protein. Our experimental findings suggest that divalent cation tolerance protein negatively regulates the function of beta-site amyloid precursor protein-cleaving enzyme 1. Thus, divalent cation tolerance protein could play a protective role in Alzheimer＇s disease.展开更多
基金supported by NIH grants NIH/NIA R01AG069401(to L.Q.)NIH/NHLBI U54HL165442(to K.T.)P30AR069619(to Penn Center for Musculoskeletal Disorders).
文摘Bone resorption by osteoclasts is a critical step in bone remodeling,a process important for maintaining bone homeostasis and repairing injured bone.We previously identified a bone marrow mesenchymal subpopulation,marrow adipogenic lineage precursors(MALPs),and showed that its production of RANKL stimulates bone resorption in young mice using Adipoq-Cre.To exclude developmental defects and to investigate the role of MALPs-derived RANKL in adult bone,we generated inducible reporter mice(Adipoq-CreER Tomato)and RANKL deficient mice(Adipoq-CreER RANKLflox/flox,iCKO).Single cell-RNA sequencing data analysis and lineage tracing revealed that Adipoq+cells contain not only MALPs but also some mesenchymal progenitors capable of osteogenic differentiation.In situ hybridization showed that RANKL mRNA is only detected in MALPs,but not in osteogenic cells.RANKL deficiency in MALPs induced at 3 months of age rapidly increased trabecular bone mass in long bones as well as vertebrae due to diminished bone resorption but had no effect on the cortical bone.Ovariectomy(OVX)induced trabecular bone loss at both sites.RANKL depletion either before OVX or at 6 weeks post OVX protected and restored trabecular bone mass.Furthermore,bone healing after drill-hole injury was delayed in iCKO mice.Together,our findings demonstrate that MALPs play a dominant role in controlling trabecular bone resorption and that RANKL from MALPs is essential for trabecular bone turnover in adult bone homeostasis,postmenopausal bone loss,and injury repair.
基金supported by the National Natural Science Foundation of China(Nos.42371094,41907253)partially supported by the Interdisciplinary Cultivation Program of Xidian University(No.21103240005)the Postdoctoral Fellowship Program of CPSF(No.GZB20240589)。
文摘INTRODUCTION.On May 1st,2024,around 2:10 a.m.,a catastrophic collapse occurred along the Meilong Expressway near Meizhou City,Guangdong Province,China,at coordinates 24°29′24″N and 116°40′25″E.This collapse resulted in a pavement failure of approximately 17.9 m in length and covering an area of about 184.3 m^(2)(Chinanews,2024).
基金Project (2011CB605801) supported by the National Basic Research Program of ChinaProject (CX2012B042) supported by the Graduated Students' Scientific Research Innovation Project in Hunan Province of China
文摘C/C-ZrC composites were prepared by precursor infiltration and pyrolysis using the organic zirconium as precursor.The conversion mechanisms of the precursors such as the thermal behavior,structural evolution,phase composition,microstructure,composition of the precursors and products were analyzed by thermal gravimetric analyzer,Fourier transform infrared spectrometer,X-ray diffraction and scanning electron microscope.The results indicate that the ZrC precursor transforms to inorganic ZrO2 from room temperature to 1200 ℃,then reduces to ZrC at 1600 ℃ through the carbothermal reduction reaction.The microstructure of the C/C-ZrC composites was also investigated.The composites exhibit an interesting structure,a coating composed of ZrC ceramic covers the exterior of the composite,and the ZrC ceramic is embedded in the pores of the matrix inside the composite.
基金supported by the National Natural Science Foundation of China(Nos.52374119,42477142 and 42277154)Natural Science Foundation of Jiangsu Province(No.BK20242059)+1 种基金the open fund of State Key Laboratory of Hydraulics and Mountain River Engineering(No.SKHL2306)the High-level Talent Introduction Project of Changzhou University(No.ZMF24020037)。
文摘Rockburst precursors are critical for disaster warning,yet the complexity of rockburst has hindered the identification of a unified precursor.Furthermore,the influence of loading rates(LRs)on acoustic emission(AE)precursors in different rock types remains poorly understood.This study investigates the AE characteristics and early warning times of rockburst in slate and mica-schist under four LRs(0.05,0.15,0.25,and 0.5 MPa/s)using true triaxial unloading tests.The micro-crack state of the samples was evaluated using entropy,while critical slowing down(CSD)theory was applied to interpret AE precursors.The results reveal that as the LR increases,the rockburst stress of both rocks initially rises and then declines,with mica-schist exhibiting more severe damage and a higher dominance of tensile cracks.Notably,identifying rockburst precursors in mica-schist proved more challenging compared to slate.Among the methods tested,AE amplitude variance outperformed entropy in precursor identification.Additionally,the rockburst early warning time was found to be negatively correlated with the LR,with mica-schist consistently showing shorter warning times than slate.The CSD-derived precursor,due to its enhanced sensitivity,is recommended for early warning systems.These findings provide new insights into the role of LRs in rockburst dynamics and offer practical guidance for improving precursor identification and disaster mitigation strategies.
文摘Polyacrylonitrile (PAN) precursor is a core precursor for the preparation of high-performance carbon fibers. Its unique chemical structure and physical properties directly contributes to the microstructure and mechanical properties of carbon fibers, and therefore affect the overall performance of pultruded composites. This study systematically investigated the influence of PAN precursor properties on the degree of graphitization, surface morphology and mechanical properties of carbon fibers by regulating the molecular weight distribution, stretching ratio and impurity content of PAN precursor, and analyzed the mechanism of action of carbon fiber properties on the interfacial bonding strength and tensile/ bending properties of composites in combination with the pultrusion process. The results showed that when the filament stretchability was increased to 4.5 times, the axial orientation of carbon fibers increased by 18% and the tensile strength reached 520 MPa;Filaments with impurity content below 0.3% increase carbon fiber yield by 5.2% and interlaminar shear strength of composites by 23%. This study provides a theoretical basis for raw material screening and process optimization of high-performance carbon fibers and their composites.
文摘The increasing sophistication of cyberattacks,coupled with the limitations of rule-based detection systems,underscores the urgent need for proactive and intelligent cybersecurity solutions.Traditional intrusion detection systems often struggle with detecting early-stage threats,particularly in dynamic environments such as IoT,SDNs,and cloud infrastructures.These systems are hindered by high false positive rates,poor adaptability to evolving threats,and reliance on large labeled datasets.To address these challenges,this paper introduces CyberGuard-X,an AI-driven framework designed to identify attack precursors—subtle indicators of malicious intent—before full-scale intrusions occur.CyberGuard-X integrates anomaly detection,time-series analysis,and multi-stage classification within a scalable architecture.The model leverages deep learning techniques such as autoencoders,LSTM networks,and Transformer layers,supported by semi-supervised learning to enhance detection of zero-day and rare threats.Extensive experiments on benchmark datasets(CICIDS2017,CSE-CIC-IDS2018,and UNSW-NB15)demonstrate strong results,including 96.1%accuracy,94.7%precision,and 95.3%recall,while achieving a zero-day detection rate of 84.5%.With an inference time of 12.8 ms and 34.5%latency reduction,the model supports real-time deployment in resource-constrained environments.CyberGuard-X not only surpasses baseline models like LSTM and Random Forest but also enhances proactive threat mitigation across diverse network settings.
基金Projects(51934007,12072363,52004268) supported by the National Natural Science Foundation of ChinaProject(22KJD440002) supported by the Natural Science Fund for Colleges and Universities in Jiangsu Province,China。
文摘This study investigates the instability characteristics of dynamic disasters resulting from disruption caused by extracting resources underground. Utilizing the split Hopkinson pressure bar (SHPB) system, the dynamic response mechanism of coal energy evolution is examined, and the energy instability criterion is established. The validity of the instability criterion is explored from the standpoint of damage progression. The results demonstrate that the energy conversion mechanism undergoes a fundamental alternation under impact disturbance. Moreover, the energy release rate as well as the energy dissipation rate undergo comparable changes across distinct levels of impact disturbance. The distinction between the energy release rate and the energy dissipation rate (DRD) increases as coal mass deformation grows. Prior to coal facing instability and failure, the DRD experienced an inflection point followed by a sharp decrease. In conjunction with the discussion on the damage evolution, the physical and mechanical significance of DRD remains clear, which can essentially describe the whole impact loading process. The phenomenon that the inflection point appears and DRD subsequently suddenly decreases can be employed as the energy criterion prior to the failure of instability. Furthermore, this paper provides significant reference for the prediction of dynamic instability of coal under dynamic disturbance.
基金supported by the National Research Foundation of Korea(NRF)grants funded by the Korea government(MSIT)(Nos.RS-2024–00351052 and RS-2024–00450561)。
文摘Metal composites produced through the liquid metal dealloying(LMD)process feature an advanced matrix-matrix composite structure,where two metallic materials form a continuous,three-dimensional interconnected network.This study investigates the effects of Ti Cu precursor compositions on dealloying behavior and microstructural evolution in liquid Mg,using Ti_(50)Cu_(50)and Ti_(30)Cu_(70)precursors.The initial microstructure of the precursor significantly influences dealloying kinetics and phase transitions.The single-phase Ti_(50)Cu_(50)precursor exhibits a faster initial dealloying rate due to its homogeneous structure,yet complete dealloying requires 90 min.In contrast,the dualphase Ti_(30)Cu_(70)precursor achieves complete dealloying in 30 min,demonstrating the impact of a higher Cu concentration on accelerating the process kinetics.Additionally,the study explores the coarsening behavior and hardness variations during the LMD process,along with the microstructural characteristics of Mg-Ti composites fabricated from these two precursors.The findings highlight the critical role of precursor composition in tailoring the microstructure and properties of Mg-Ti composites produced through the LMD process,demonstrating its potential for advanced composite material manufacturing.
基金supported by the Key Program of the National Natural Science Foundation of China(No.52032003)the Major Program of the National Natural Science Foundation of China(No.52293372)+2 种基金the National Natural Science Foundation of China(No.51972082)the National Natural Science Foundation of China(No.52102093)the National Natural Science Foundation of China(No.52172041)and the science foundation of national key laboratory of science and technology on advanced composites in special environments.
文摘The current generation of ultrahigh temperature ceramic precursors typically encounters obstacles in achieving high ceramic yields(<40 wt.%)due to the challenges in integrating significant amounts of boron,which hampers their conversion into boride-based ultrahigh temperature ceramics.To tackle these challenges,a serious of pioneering liquid multi-component hafnium-containing ceramic SiHfCB precursors(with different Hf/Si ratios)have been developed.These novel precursors are featured with stable molec-ular structure and high ceramic yield which were successfully created through a novel one-pot polymer-ization process.They present in liquid form and their structure is characterized by C-C bonds forming its main chain with branched chains of O-Si-O,Si-O-Hf,Si-O-B,and B-O-Hf which have untapped advantages including uniform component dispersion,and excellent fluidity.The ceramic yield of SiHfCB precursor with Hf/Si of 0.2 is remarkably up to 68.6 wt.%at 1500℃,and their Hf content exceeded 50 wt.%.Of particular interest,the pyrolyzed product HfB_(2)-SiC nanopowders derived from the SiHfCB precursor with Hf/Si of 0.2,consist of nanopowders in the 40-60 nm range with a density of 5.23 g cm^(−3).Remarkably,this material demonstrates exceptional performance in ultrahigh temperature oxygen-containing environ-ments at 2500℃,showing near-zero ablation with a linear ablation rate of just 2.5×10^(−4) mm s^(−1).Post-ablation analysis of the microstructure reveals that the formation of a lava-like HfO_(2) and HfO_(2)-SiO_(2) oxide layer effectively blocks oxygen penetration and provides excellent oxidation resistance.The inno-vative SiHfCB hafnium-containing ceramic precursor offers a groundbreaking solution for the preparation of lightweight ultrahigh-temperature ceramics.This development is poised to provide robust technical support for the use of ultrahigh temperature ceramics in non-ablative thermal protective systems,partic-ularly in the construction of hypersonic vehicles,where ultrahigh temperature resilience is crucial.
基金supported by grants from the State Key Program of the National Natural Science Foundation of China(grant number 82030064)Beijing Hospital Authority Youth Program(grant number QML20230812)+2 种基金Research and Development Foundation of Capital Medical University(grant number PYZ23052)National Natural Science Youth Cultivation Project of Xuanwu Hospital,Capital Medical University(grant number QNPY202317)Capital Medical University Research and Cultivation Fund(grant number PYZ23049).
文摘Objective To reveal the effects and potential mechanisms by which synaptic vesicle glycoprotein 2A(SV2A)influences the distribution of amyloid precursor protein(APP)in the trans-Golgi network(TGN),endolysosomal system,and cell membranes and to reveal the effects of SV2A on APP amyloid degradation.Methods Colocalization analysis of APP with specific tagged proteins in the TGN,ensolysosomal system,and cell membrane was performed to explore the effects of SV2A on the intracellular transport of APP.APP,β-site amyloid precursor protein cleaving enzyme 1(BACE1)expressions,and APP cleavage products levels were investigated to observe the effects of SV2A on APP amyloidogenic processing.Results APP localization was reduced in the TGN,early endosomes,late endosomes,and lysosomes,whereas it was increased in the recycling endosomes and cell membrane of SV2A-overexpressed neurons.Moreover,Arl5b(ADP-ribosylation factor 5b),a protein responsible for transporting APP from the TGN to early endosomes,was upregulated by SV2A.SV2A overexpression also decreased APP transport from the cell membrane to early endosomes by downregulating APP endocytosis.In addition,products of APP amyloid degradation,including sAPPβ,Aβ1-42,and Aβ1-40,were decreased in SV2A-overexpressed cells.Conclusion These results demonstrated that SV2A promotes APP transport from the TGN to early endosomes by upregulating Arl5b and promoting APP transport from early endosomes to recycling endosomes-cell membrane pathway,which slows APP amyloid degradation.
基金Supported by The Science and Technology Research Project of Anyang,No.2022C01SF074。
文摘BACKGROUND Differential diagnosis among atypical hyperplasia(AH)(including reparative hyperplasia and intestinal metaplasia),low-grade dysplasia(LGD),high-grade dysplasia(HGD),and adenocarcinoma(AC)in gastric mucosal biopsies is challenging due to histomorphological overlaps,variability in pathological diagnosis consistency,and limited reproducibility.AIM To evaluate the diagnostic utility of P53,Ki67,P504S,and IMP3 in gastric cancer and its precancerous lesions,focusing on their effectiveness in distinguishing AH,LGD,HGD,and AC.METHODS From January 2018 to September 2020,a total of 185 gastric mucosal biopsy specimens were analyzed according to the pathological diagnostic criteria outlined in the World Health Organization Classification of Digestive System Tumors(2019).The specimens were categorized into four groups:AH,LGD,HGD,and AC.Immunohistochemistry was employed to assess the expression status of P53,Ki67,P504S,and IMP3.Intergroup comparisons were performed using theχ^(2)test or Fisher's exact probability test to compare the differences in immunohistochemical markers across the distinct lesion groups.RESULTS The expression rate of P504S was highest in the LGD group(53.3%,16/30),while IMP3 expression was highest in the AC group(41.9%,26/62),followed by the HGD group(33.3%).Significant differences in P504S and IMP3 expression levels were observed among the four lesion groups(P<0.001).Pairwise comparisons revealed statistically significant differences in P504S expression between the AH group and the LGD,HGD,and AC groups(P<0.001),as well as significant variations in IMP3 expression between the AH group and the HGD and AC groups,and between the LGD group and the HGD and AC groups(P<0.001).Additionally,significant correlations were found between P504S and the polarity expression pattern of Ki67,and between IMP3 and the mutation expression pattern of P53(P<0.001).The combined detection of P504S with Ki67 and IMP3 with P53 increased the diagnostic sensitivity for LGD and HGD/AC,respectively.CONCLUSION P504S is highly expressed in LGD and is associated with the Ki67“polarity”expression pattern.IMP3 is highly expressed in HGD/AC and is correlated with the P53 mutation expression pattern.The combined detection of P504S with Ki67 and IMP3 with P53 increased the diagnostic sensitivity for LGD and HGD/AC,respectively.The rational use of P504S,Ki67,IMP3,and p53 can help distinguish gastric cancer and precancerous lesions,improving the early cancer diagnosis rate.
基金supported by the National Natural Science Foundation of China(82130036)the STI2030-Major Projects(2022ZD0211800)Jiangsu Province Key Medical Discipline(ZDXK202216).
文摘Chronic cerebral hypoperfusion leads to white matter injury(WMI),which plays a significant role in contributing to vascular cognitive impairment.While 13-docosenamide is a type of fatty acid amide,it remains unclear whether it has therapeutic effects on chronic cerebral hypoperfusion.In this study,we conducted bilateral common carotid artery stenosis(BCAS)surgery to simulate chronic cerebral hypoperfusion-induced WMI and cognitive impairment.Our findings showed that 13-docosenamide alleviates WMI and cognitive impairment in BCAS mice.Mechanistically,13-docosenamide specifically binds to cannabinoid receptor 1(CNR1)in oligodendrocyte precursor cells(OPCs).This interaction results in an upregulation of ubiquitin-specific peptidase 33(USP33)-mediated CNR1 deubiquitination,subsequently increasing CNR1 protein expression,activating the phosphorylation of the AKT/mTOR pathway,and promoting the differentiation of OPCs.In conclusion,our study suggests that 13-docosenamide can ameliorate chronic cerebral hypoperfusion-induced WMI and cognitive impairment by enhancing OPC differentiation and could serve as a potential therapeutic drug.
基金supported by the National Natural Science Foundation of China(No.52202090)the Fundamental Research Funds for the Central Universities(No.2082019014).
文摘Thorium dioxide(ThO_(2))fibers exhibit exceptional structural stability,low density and superior flexibility,coupled with a remarkably high melting point,positioning them as promising candidates for thermal protection applications.Additionally,their commendable secondary processing characteristics enable the development of diverse composite materials when integrated with other materials,significantly broadening the potential utilization of ThO_(2)materials and thorium resources in industrial fields.In this work,the ThO_(2)fiber was fabricated by the sol-gel precursor method,and the precursor with good spinnability and excellent stability was synthesized for the first time.The ThO_(2)fiber with a mean diameter of 868 nm is both highly flexible and strong(max.tensile strength 2.21 MPa),capable of bending freely across a wide temperature range from-196℃(in liquid nitrogen)to 1200℃.Meanwhile,it exhibits excellent temperature stability and heat insulation properties.The ThO_(2)nanofiber membranes with layered structure have low density(32-37 mg·cm^(-3)),low thermal conductivity(27.3-30.1 mW·m^(-1)·K^(-1)@25℃).The ThO_(2)nanofiber membranes with 15 mm thickness can reduce the temperature from 1200 to 282℃and maintain a high aspect ratio and bendability after 1200℃@90 min.The results show that the ThO_(2)fiber can be used as a new kind of high-temperature resistant material.
基金supported by the National Research Foundation of Korea(NRF)funded by the government of the Republic of Korea[2023R1A2C1004955]the Technology Innovation Program funded by the Ministry of Trade,Industry&Energy(Korea)(20009707)+1 种基金the Basic Science Research Program through the National Research Foundation of Korea(NRF)funded by the Ministry of Education(2020R1A6A3A01099056)the Korea Institute for Advancement of Technology funded by the Ministry of Trade,Industry and Energy(P0025489).
文摘Infiltration and activation of peripheral immune cells are critical in the progression of multiple sclerosis and its experimental animal model,experimental autoimmune encephalomyelitis(EAE).This study investigates the role of high mobility group box 1(HMGB1)in oligodendrocyte precursor cells(OPCs)in modulating pathogenic T cells infiltrating the central nervous system through the blood-brain barrier(BBB)by using OPC-specific HMGB1 knockout(KO)mice.We found that HMGB1 released from OPCs promotes BBB disruption,subsequently allowing increased immune cell infiltration.The migration of CD4+T cells isolated from EAE-induced mice was enhanced when co-cultured with OPCs compared to oligodendrocytes(OLs).OPC-specific HMGB1 KO mice exhibited lower BBB permeability and reduced immune cell infiltration into the CNS,leading to less damage to the myelin sheath and mitigated EAE progression.CD4+T cell migration was also reduced when co-cultured with HMGB1 knock-out OPCs.Our findings reveal that HMGB1 secretion from OPCs is crucial for regulating immune cell infiltration and provides insights into the immunomodulatory function of OPCs in autoimmune diseases.
基金supported by National Natural Science Foundation of China(82472473,81991510,81991511 and 81820108020)Major Scientific Research Project of Health in Fujian Province(20212D01003)+3 种基金Fujian Province Joint Fund Project for Science and Technology Innovation(2021Y9023,2023Y9601)China Postdoctoral Science Foundation(2022M710702)Fujian Provincial Natural Science Foundation Projects(2023J01177,2023J011209,2023J01172)Fujian Provincial Health Technology Project(2023GGA004)。
文摘Osteoclast-development patterns and their alterations across Ankylosing Spondylitis(AS)conditions are mysterious,making AS treatment difficult.Our study aims to clarify osteoclast-precursor(OCP)development patterns from monocytes and their variations under AS conditions.We performed single-cell transcriptomics in peripheral blood mononuclear cells(PBMCs)from healthy donors and AS patients in the early,aggravated and remission stages.After monocytic reclustering,OCP-development patterns and the alterations upon AS onset and different outcomes were revealed based on single-cell trajectory.The trajectories revealed two monocyte states with strong OCP features,and AS pathogenesis was characterized by their reduction.Ribosome synthesis was considered the essential function for the development towards OCP-featured states,and this function and its representative molecule,RPS17,showed a decreasing trend with AS onset and outcomes.Histology assessment showed that RPS17underexpression participated in AS inflammatory osteogenesis and ankylosing destruction.Conditional knockout of RPS17ameliorated ovariectomy-induced bone loss and enhanced osteoclastogenesis,and RPS17 overexpression improved the phenotype of AS-like mice.Importantly,local injection of RPS17-overexpressed monocytic OCPs markedly ameliorated the joint alterations of AS-like mice without promoting bone loss;this was associated with enhanced osteoclastogenesis adjacent to the articular surface and T-cell-suppressive property in monocytic OCPs.Overall,the evolution of monocytes towards OCP-lineage fate mainly depends on ribosome synthesis,and OCP-development disorder participates in AS lesions due to a reduction in RPS17-dependent ribosome synthesis.Notably,RPS17-overexpressed monocytic OCPs have translational potential in preventing and treating AS peripheral lesions.
基金financially supported by the National Natural Science Foundation of China(Nos.52271034,52301058 and 52471042)the National MCF Energy R&D Program of China(No.2018YFE0306102)+1 种基金the China Postdoctoral Science Foundation(No.2023M732183)the Postdoctoral Fellowship Program of CPSF(No.GZB20230399).
文摘To develop a melting-based larger-scale fabrication process for oxide dispersion strengthened(ODS)steel,this study proposed a method of zone melting with built-in precursor powder(ZMPP),followed by hot forging and aging treatments.A 50 kg ingot was successfully prepared,highlighting the scalability of this innovative process.Microstructural analysis revealed a predominantly lath martensite matrix with a small amount of ferrite in the hot-forged ODS steel,without oxide particle aggregation.Aging at 750℃ resulted in the formation of sub-micron-sized Cr_(23)C_(6) particles at grain boundaries and martensitic lath interfaces,accompanied by a high-density(7.64×1023 m^(-3))nano-scale(~6 nm)Y-Si-O complex oxides after 25 h.Additionally,the hot-forged sample exhibited a high yield strength(871 MPa)but limited ductility(5.0%).Aging treatments led to an increase in ductility but a decrease in yield strength.Notably,prolonged aging maintained the strength level of steels while enhancing ductility,with a 23.3% total elongation observed after 25 h.The novel ZMPP method,preparing high-quality ODS steels with uniform microstructure and good mechanical properties,provided a new avenue for large-scale production of ODS steels.
基金supported by the Major Science and Technology Project of Shenzhen’s Innovation and Entrepreneurship Program(Grant No.KJZD20231023100301004)Foshan Science and Technology Innovation Team Project(1920001004098)the Hydrometal urgy and Battery Materials Laboratory at PT.QMB New Energy Materials(Indonesia)under GEM Co.,Ltd.(China)as a company group。
文摘The LiNi_(x)Co_(y)Mn_(1-x-y)O_(2)(NCM)cathode materials have emerged as critical components in lithium-ion batteries due to their high energy and power densities.The co-precipitation method is widely used in laboratory and industry settings to optimize the crystallinity,grain morphology,particle size,and sphericity of precursor materials,directly affecting NCM battery performance.This review addresses the nucleation mechanism and the thermodynamic and kinetic reaction processes of co-precipitation.The comprehensive effects of key parameters on precursor physicochemical properties are also systematically interpreted.
基金supported as part of the"2024 Groundwater Basic Survey Project,"funded by the Ministry of Environment(Project No.20240123-001)。
文摘Earthquakes can cause significant hazards,leading to loss of human life and property damage.In this study,we applied the masking empirical mode decomposition(EMD)to the Gyeongju earthquake(ML 5.8)in South Korea and the Abe Pura earthquake(ML 7.0)in Indonesia and then revealed that the 7th intrinsic mode function(IMF7),composed of waveforms with a period band of approximately 150 to 750 minutes.
基金Project supported in part by the Science and Technology Development Plan Project of Jilin Province, China (Grant No. YDZJ202303CGZH022)the National Key Research and Development Program of China (Grant No. 2024YFE0205300)+1 种基金the National Natural Science Foundation of China (Grant No. 62471504)the Open Fund of the State Key Laboratory of Optoelectronic Materials and Technologies (Sun Yat-Sen University) (Grant No. OEMT-2023KF-05)。
文摘Metal–insulator–semiconductor(MOS) capacitor is a key structure for high performance MOS field transistors(MOSFETs), requiring low leakage current, high breakdown voltage, and low interface states. In this paper, β-Ga_(2)O_(3) MOS capacitors were fabricated with ALD deposited Al_(2)O_(3) using H_(2)O or ozone(O_(3)) as precursors. Compared with the Al_(2)O_(3) gate dielectric with H_(2)O as ALD precursor, the leakage current for the O_(3) precursor case is decreased by two orders of magnitude, while it keeps the same level at the fixed charges, interface state density, and border traps. The SIMS tests show that Al_(2)O_(3) with O_(3) as precursor contains more carbon impurities. The current transport mechanism analysis suggests that the C–H complex in Al_(2)O_(3) with O_(3) precursor serves as deep energy trap to reduce the leakage current. These results indicate that the Al_(2)O_(3)/β-Ga_(2)O_(3)MOS capacitor using the O_(3) precursor has a low leakage current and holds potential for application in β-Ga_(2)O_(3) MOSFETs.
基金supported by the National Natural Science Foundation of China, No. 81171192XMU Basic Training Program of Undergraduate, No. CXB2011019Visiting Scholar Fellowship of Key Laboratory of Ministry of Education for Cell Biology and Tumor Cell Engineering of Xiamen University, No. 201101
文摘The deposition of amyloid-beta is a pathological hallmark of Alzheimer＇s disease, Amyloid-beta is derived from amyloid precursor protein through sequential proteolytic cleavages by β-secretase （beta-site amyloid precursor protein-cleaving enzyme 1） and r-secretase. To further elucidate the roles of beta-site amyloid precursor protein-cleaving enzyme 1 in the development of AIzheimer＇s disease, a yeast two-hybrid system was used to screen a human embryonic brain cDNA library for proteins directly interacting with the intracellular domain of beta-site amyloid precursor protein-cleaving enzyme 1. A potential beta-site amyloid precursor protein-cleaving enzyme 1- interacting protein identified from the positive clones was divalent cation tolerance protein. Immunoprecipitation studies in the neuroblastoma cell line N2a showed that exogenous divalent cation tolerance protein interacts with endogenous beta-site amyloid precursor protein-cleaving enzyme 1. The overexpression of divalent cation tolerance protein did not affect beta-site amyloid precursor protein-cleaving enzyme 1 protein levels, but led to increased amyloid precursor protein levels in N2a/APP695 cells, with a concomitant reduction in the processing product amyloid precursor protein C-terminal fragment, indicating that divalent cation tolerance protein inhibits the processing of amyloid precursor protein. Our experimental findings suggest that divalent cation tolerance protein negatively regulates the function of beta-site amyloid precursor protein-cleaving enzyme 1. Thus, divalent cation tolerance protein could play a protective role in Alzheimer＇s disease.
