We propose an optimization method based on evolutionary computation for the design of broadband high-efficiency current-biased reverse load-modulation power amplifiers(CB-RLM PAs).First,given the reverse load-modulati...We propose an optimization method based on evolutionary computation for the design of broadband high-efficiency current-biased reverse load-modulation power amplifiers(CB-RLM PAs).First,given the reverse load-modulation characteristics of CB-RLM PAs,a comprehensive objective function is proposed that combines multi-state impedance trajectory constraints with in-band performance deviations.For the saturation and 6 dB power back-off(PBO)states,approximately optimal impedance regions on the Smith chart are derived using impedance constraint circles based on load-pull simulations.These regions are used together with in-band performance deviations(e.g.,saturated efficiency,6 dB PBO efficiency,and saturated output power)for matching network optimization and design.Second,a multi-objective evolutionary algorithm based on decomposition with adaptive weights,neighborhood,and global replacement is integrated with harmonic balance simulations to optimize design parameters and evaluate performance.Finally,to validate the proposed method,a broadband CB-RLM PA operating from 0.6 to 1.8 GHz is designed and fabricated.Measurement results show that the efficiencies at saturation,6 dB PBO,and 8 dB PBO all exceed 43.6%,with saturated output power being maintained at 40.9–41.5 dBm,which confirms the feasibility and effectiveness of the proposed broadband high-efficiency CB-RLM PA optimization and design approach.展开更多
Lysine-targeting reversible covalent inhibitors,particularly salicylaldehyde-based compounds such as the Food and Drug Administration(FDA)-approved drug Voxelotor,exhibit significant therapeutic potential but are limi...Lysine-targeting reversible covalent inhibitors,particularly salicylaldehyde-based compounds such as the Food and Drug Administration(FDA)-approved drug Voxelotor,exhibit significant therapeutic potential but are limited by challenges including instability and off-target effects.To overcome these limitations in kinase inhibitor A5,we devised a pH-responsive prodrug strategy by masking its reactive aldehyde group with an acid-labile hydrazone linkage and enhancing intracellular delivery through conjugation with FK506.The optimized prodrug demonstrated robust antitumor efficacy in K562 tumor-bearing mice.Furthermore,the incorporation of the photosensitizer chlorin e6(Ce6)led to the formation of self-assembled nanoparticles(AKNP),which not only improved physiological stability and prolonged tumor retention but also enabled light-triggered release of A5 in conjunction with photodynamic therapy(PDT).Our study thus presents a promising prodrug self-assembly strategy that combines the on-demand release of a novel lysine-targeting,reversible covalent kinase inhibitor with PDT in clinical cancer therapy.展开更多
The nervous system function requires a precise but plastic neural architecture.The neuronal shape dictates how neurons interact with each other and with other cells,being the morphology of dendrites and axons the cent...The nervous system function requires a precise but plastic neural architecture.The neuronal shape dictates how neurons interact with each other and with other cells,being the morphology of dendrites and axons the central determinant of the functional properties of neurons and neural circuits.The topological and structural morphology of axons and dendrites defines and determines how synapses are conformed.The morphological diversity of axon and dendrite arborization governs the neuron’s inputs,synaptic integration,neuronal computation,signal transmission,and network circuitry,hence defining the particular connectivity and function of the different brain areas.展开更多
Conversion-type electrode materials hold significant promise for potassium-ion batteries(PIBs)due to their high theoretical capacities,yet their practical deployment is hindered by sluggish kinetics and irreversible s...Conversion-type electrode materials hold significant promise for potassium-ion batteries(PIBs)due to their high theoretical capacities,yet their practical deployment is hindered by sluggish kinetics and irreversible structural degradation.To overcome these limitations,we propose a rationally engineered nanoreactor architecture that stabilizes defect-rich MoS_(2)via interlayer incorporation of a carbon monolayer,followed by encapsulation within a nitrogen-doped carbon shell,forming a MoSSe@NC heterostructure.This tailored structure synergistically accelerates both K^(+)diffusion kinetics and electron transfer,enabling unprecedented rate performance(107 mAh g^(-1)at 10 Ag^(-1))and ultralong cyclability(86.5%capacity retention after 1200 cycles at 3 A g^(-1)).Mechanistic insights reveal a distinctive“adsorption-conversion”pathway,where sulfur vacancies on exposed S-Mo-S basal planes act as preferential K^(+)adsorption sites,effectively suppressing parasitic phase transitions during intercalation.In situ X-ray diffraction and transmission electron microscopy corroborate the structural reversibility of the conversion reaction,with the carbon matrix dynamically accommodating strain while preserving electrode integrity.This work not only advances the understanding of defect-driven interfacial chemistry in conversion-type materials but also provides a versatile strategy for designing high-performance anodes in next-generation PIBs through heterostructure engineering.展开更多
BACKGROUND The optimal surgical approach for patients with primary glenohumeral osteoarthritis(GHOA)and an intact rotator cuff remains debated.While anatomic total shoulder arthroplasty(TSA)has traditionally been favo...BACKGROUND The optimal surgical approach for patients with primary glenohumeral osteoarthritis(GHOA)and an intact rotator cuff remains debated.While anatomic total shoulder arthroplasty(TSA)has traditionally been favoured,reverse TSA(RTSA)is increasingly utilized.AIM To systematically compare the outcomes of RTSA and TSA in this specific patient population.METHODS A systematic review and meta-analysis were conducted in accordance with PRISMA guidelines.Retrospective comparative studies evaluating RTSA and TSA in patients with GHOA and intact rotator cuff were included.Key outcomes assessed included complication and reoperation rates,patient-reported outcome measures(PROMs),and range of motion.Risk of bias was assessed using the Risk of Bias in Non-randomized Studies of Interventions tool.RESULTS Twelve studies encompassing 1608 patients(580 RTSA,1028 TSA)met inclusion criteria.RTSA was associated with a lower reoperation rate compared to TSA[odds ratio=0.37;95%confidence interval(CI):0.14-0.94;P value=0.04],while no significant difference in overall complication rates was observed(odds ratio=0.47;95%CI:0.19-1.16;P value=0.10).RTSA patients showed superior outcomes in University of California Los Angeles,Simple Shoulder Test,and Shoulder Pain and Disability Index scores;however,the differences did not exceed the minimal clinically important difference.TSA patients had significantly better external rotation(mean difference=-9.0°;95%CI:-13.21 to-5.02;P value<0.0001).No significant differences were found in other range of motion measures or satisfaction scores.The overall methodological quality of included studies was moderate to serious.CONCLUSION In patients with GHOA and an intact rotator cuff,RTSA may offer comparable or improved outcomes to TSA with lower reoperation rates and similar complication profiles.Functional outcomes favour RTSA in certain patientreported outcome measures,while TSA retains an advantage in external rotation.Surgical decision-making should remain individualized based on patient characteristics and functional demands.展开更多
Ceramic 4D printing,which integrates dynamic deformation with additive manufacturing,demonstrates significant potential in intelligent manufacturing,on-demand shaping of complex structures,and multifunctional device d...Ceramic 4D printing,which integrates dynamic deformation with additive manufacturing,demonstrates significant potential in intelligent manufacturing,on-demand shaping of complex structures,and multifunctional device development.Its core advantage lies in endowing materials with environmentally responsive dynamic deformation capabilities.However,current technologies still face limitations in responsiveness,reversibility,and mechanical performance.To address these challenges,this study proposes a programmable ceramic precursor system based on synergistic reinforcement of phase-separating hydrogels and shape memory polymers,combined with a nano-ceramic particle enhancement strategy.Using stereolithography 3D printing,high-precision fabrication of complex structures was achieved.By adjusting precursor composition,programming time,and structural thickness,the phase-separation kinetics-driven delayed recovery mechanism was elucidated,enabling precise control over recovery onset time.Furthermore,the thermal response mechanism of the precursor materials is explored,along with their potential for multi-shape transformation in biomedical applications,which is further extended to shape memory polymer systems.By employing a layered printing strategy,the autonomous reversible deformation of ceramic precursors is realized,providing new possibilities for specific applications.展开更多
Reversible data hiding(RDH)enables secret data embedding while preserving complete cover image recovery,making it crucial for applications requiring image integrity.The pixel value ordering(PVO)technique used in multi...Reversible data hiding(RDH)enables secret data embedding while preserving complete cover image recovery,making it crucial for applications requiring image integrity.The pixel value ordering(PVO)technique used in multi-stego images provides good image quality but often results in low embedding capability.To address these challenges,this paper proposes a high-capacity RDH scheme based on PVO that generates three stego images from a single cover image.The cover image is partitioned into non-overlapping blocks with pixels sorted in ascending order.Four secret bits are embedded into each block’s maximum pixel value,while three additional bits are embedded into the second-largest value when the pixel difference exceeds a predefined threshold.A similar embedding strategy is also applied to the minimum side of the block,including the second-smallest pixel value.This design enables each block to embed up to 14 bits of secret data.Experimental results demonstrate that the proposed method achieves significantly higher embedding capacity and improved visual quality compared to existing triple-stego RDH approaches,advancing the field of reversible steganography.展开更多
Sluggish kinetics coupled with parasitic shuttling reactions are pivotal challenges hindering the performance of lithium-sulfur(Li-S)batteries.Improving areal capacity and cyclability of Li-S batteries can be achieved...Sluggish kinetics coupled with parasitic shuttling reactions are pivotal challenges hindering the performance of lithium-sulfur(Li-S)batteries.Improving areal capacity and cyclability of Li-S batteries can be achieved by addressing these challenges.A composite sulfur host material is synthesized herein by in situ anchoring ultrafine cobalt-iron phosphide nanoparticles(5-7 nm)onto a hollow mesoporous carbon sphere(HMCS)framework.This strategy achieved exceptional spatial restriction and a high density of catalytically active sites through the encapsulation of sulfur within a hollow-structured framework.Specifically,HMCS expedites rapid Li_(2)S nucleation kinetics,while CoFeP facilitates robust Li_(2)S dissolution kinetics by mitigating decomposition barriers.This synergistic integration equips CoFeP@HMCS with robust bi-directional catalytic activity,significantly promoting interracial charge-transfer,facilitate sulfu r multistep catalytic conversion,and inhibiting shuttling.Consequently,the battery exhibits excellent rate performance(991 mA h g^(-1) at 5.0 C)and retains a high areal capacity of 6.06 mA h cm^(-2) after 200 cycles under a high areal sulfur loading of 8.2 mg cm^(-2) but a low electrolyte/sulfur ratio of 4.8μL mg^(-1).This work contributes to enhancing the practical specific capacity of lithium-sulfur batteries and deepens the understanding of catalysts enabling bidirectional electrocatalytic sulfur conversion.展开更多
To enhance power flow regulation in scenarios involving large-scale renewable energy transmission via high-voltage direct current(HVDC)links and multi-infeed DC systems in load-center regions,this paper proposes a hyb...To enhance power flow regulation in scenarios involving large-scale renewable energy transmission via high-voltage direct current(HVDC)links and multi-infeed DC systems in load-center regions,this paper proposes a hybrid modular multilevel converter–capacitor-commutated line-commutated converter(MMC-CLCC)HVDC transmission system and its corresponding control strategy.First,the system topology is constructed,and a submodule configuration method for the MMC—combining full-bridge submodules(FBSMs)and half-bridge submodules(HBSMs)—is proposed to enable direct power flow reversal.Second,a hierarchical control strategy is introduced,includingMMCvoltage control,CLCC current control,and a coordinationmechanism,along with the derivation of the hybrid system’s power flow reversal characteristics.Third,leveraging the CLCC’s fast current regulation and theMMC’s negative voltage control capability,a coordinated power flow reversal control strategy is developed.Finally,an 800 kV MMC-CLCC hybrid HVDC system is modeled in PSCAD/EMTDC to validate the power flow reversal performance under a high proportion of full-bridge submodule configuration.Results demonstrate that the proposed control strategy enables rapid(1-s transition)and smooth switching of bidirectional power flow without modifying the structure of primary equipment:the transient fluctuation ofDC voltage from the rated value(UdcN)to themaximumreverse voltage(-kUdcN)is less than 5%;the DC current strictly follows the preset characteristic curve with a deviation of≤3%;the active power reverses continuously,and the system maintains stable operation throughout the reversal process.展开更多
BACKGROUND Posterior reversible encephalopathy syndrome(PRES)is a complex neurological disorder characterized by symptoms such as headaches,seizures,confusion,and visual disturbances.The pathophysiology of PRES involv...BACKGROUND Posterior reversible encephalopathy syndrome(PRES)is a complex neurological disorder characterized by symptoms such as headaches,seizures,confusion,and visual disturbances.The pathophysiology of PRES involves endothelial dysfunction,disrupted cerebral autoregulation,and resulting vasogenic edema.Hypertension and other factors that alter cerebral autoregulation are critical in its development.Corticosteroids,widely used for their anti-inflammatory and immunosuppressive properties,play a controversial role in PRES.AIM To elucidate the dual role of corticosteroids in the context of PRES by critically evaluating the existing literature.Specifically,it seeks to assess the results of PRES induced by corticosteroid therapy and the efficacy and safety of corticosteroids in the treatment of PRES.By synthesizing case reports and series,this review aims to provide a comprehensive understanding of the mechanisms,clinical presentations,and management strategies associated with corticosteroid-related PRES.METHODS The review was carried out according to the PRISMA guidelines.The databases searched included Science Direct,PubMed,and Hinari.The search strategy encompassed terms related to corticosteroids and PRES.Studies were included if they were peer-reviewed articles examining corticosteroids in PRES,excluding non-English publications,reviews,and editorials.Data on patient demographics,clinical characteristics,imaging findings,corticosteroid regimens,and outcomes were extracted.The risk of bias was evaluated using the Joanna Briggs Institute tool for case reports.RESULTS A total of 56 cases of PRES(66.1%women,33.9%men)potentially induced by corticosteroids and 14 cases in which corticosteroids were used to treat PRES were identified.Cases of PRES reportedly caused by corticosteroids showed a mean age of approximately 25.2 years,with seizures,headaches,hypertension,and visual disturbances being common clinical sequelae.Magnetic resonance findings typically revealed vasogenic edema in the bilateral parieto-occipital lobes.High-dose or prolonged corticosteroid therapy was a significant risk factor.On the contrary,in the treatment cases,corticosteroids were associated with positive outcomes,including resolution of vasogenic edema and stabilization of symptoms,particularly in patients with underlying inflammatory or autoimmune diseases.CONCLUSION Corticosteroids have a dual role in PRES,capable of both inducing and treating the condition.The current body of literature suggests that corticosteroids may play a greater role as a precipitating agent of PRES rather than treating.Corticosteroids may induce PRES through hypertension and subsequent increased cerebral blood flow and loss of autoregulation.Corticosteroids may aid in the management of PRES:(1)Enhancing endothelial stability;(2)Antiinflammatory properties;and(3)Improving blood-brain barrier integrity.Mechanisms which may reduce or mitigate vasogenic edema formation.展开更多
Pseudoephedrine (PSE) is a widely used nasal decongestant. A review by the European Medicines Agency has reported that PSE may be associated with risks of posterior reversible encephalopathy syndrome (PRES) and revers...Pseudoephedrine (PSE) is a widely used nasal decongestant. A review by the European Medicines Agency has reported that PSE may be associated with risks of posterior reversible encephalopathy syndrome (PRES) and reversible cerebral vasoconstriction syndrome (RCVS). PRES and RCVS are rare but serious conditions that affect cerebral blood flow. This review discusses the pharmacology of PSE and potential risks for PRES and RCVS and concludes that considering the common use of PSE, with over 70 million packs of PSE taken each year in the European Union and the United Kingdom, and the rare occurrence of PRES and RCVS, that the risks of developing PRES/RCVS on exposure to PSE are likely to be very low.展开更多
Dear Editor,Posterior reverse encephalopathy syndrome(PRES),manifests as a confusional state/delirium,convulsion,or acute blindness which illustrates in magnetic resonance imaging(MRI)typical bilateral white matter le...Dear Editor,Posterior reverse encephalopathy syndrome(PRES),manifests as a confusional state/delirium,convulsion,or acute blindness which illustrates in magnetic resonance imaging(MRI)typical bilateral white matter lesions.These clinical and radiological changes are reversible in two to three weeks,usually generated by acute hypertension,preeclampsia,eclampsia,immunosuppression,septicemia,and end-stage renal disease.PRES is commonly diagnosed in patients in their thirties.展开更多
Dear Editor,In this case,we discuss a teenager who experienced severe eye pain and elevated intraocular pressure(IOP)caused by reverse pupillary block,which was successfully resolved using Neodymium-doped yttrium alum...Dear Editor,In this case,we discuss a teenager who experienced severe eye pain and elevated intraocular pressure(IOP)caused by reverse pupillary block,which was successfully resolved using Neodymium-doped yttrium aluminum garnet(Nd:YAG)laser peripheral iridotomy(LPI).展开更多
Reversible solid oxide cells(RSOCs)are capable of converting various energy resources,between electricity and chemical fuels,with high efficiency and flexibility,making them suitable for grid balancing and renewable e...Reversible solid oxide cells(RSOCs)are capable of converting various energy resources,between electricity and chemical fuels,with high efficiency and flexibility,making them suitable for grid balancing and renewable energy consumption.However,the practical application of RSOCs is still limited by the insufficient activity and stability of the electrodes in different operating modes.Herein,a highly efficient symmetrical electrode composed of La_(0.3)Sr_(0.6)Ti_(0.1)Co_(0.2)Fe_(0.7)O_(3-δ)(LSTCF)nanofibers and in situ exsolved Co_(3)Fe_(7) nanoparticles is developed for boosting the performance of RSOCs.The reversible phase transition,high activity and stability of the electrode have been confirmed by a combination of experimental(e.g.,transmission electron microscopy and X-ray absorption fine structure)and computational studies.Electrolyte-supported RSOCs with the symmetrical electrode demonstrate excellent catalytic activity and stability,achieving a high peak power density of 0.98 W cm^(-2)in the fuel cell mode using H_(2)as the fuel(or 0.53 W cm^(-2)using CH_(4)as the fuel)and a high current density of 1.09 A cm^(-2) at 1.4 V in the CO_(2)electrolysis mode(or 1.03 A cm^(-2)at 1.3 V for H_(2)O electrolysis)at 800℃while maintaining excellent durability for over 100 h.展开更多
Reversible solid oxide cell(RSOC)is a new energy conversion device with significant applications,especially for power grid peaking shaving.However,the reversible conversion process of power generation/energy storage p...Reversible solid oxide cell(RSOC)is a new energy conversion device with significant applications,especially for power grid peaking shaving.However,the reversible conversion process of power generation/energy storage poses challenges for the performance and stability of air electrodes.In this work,a novel high-entropy perovskite oxide La_(0.2)Pr_(0.2)Gd_(0.2)Sm_(0.2)Sr_(0.2)Co_(0.8)Fe_(0.2)O_(3−δ)(HE-LSCF)is proposed and investigated as an air electrode in RSOC.The electrochemical behavior of HE-LSCF was studied as an air electrode in both fuel cell and electrolysis modes.The polarization impedance(Rp)of the HE-LSCF electrode is only 0.25Ω·cm^(2) at 800℃ in an air atmosphere.Notably,at an electrolytic voltage of 2 V and a temperature of 800℃,the current density reaches up to 1.68 A/cm^(2).The HE-LSCF air electrode exhibited excellent reversibility and stability,and its electrochemical performance remains stable after 100 h of reversible operation.With these advantages,HE-LSCF is shown to be an excellent air electrode for RSOC.展开更多
The austenite(γ)reversely transformed from lath martensite(LM),lath bainite(LB),granular bainite(GB)and pearlite+ferrite(P+F)in a high-strength steel was studied at high temperatures using in-situ electron backscatte...The austenite(γ)reversely transformed from lath martensite(LM),lath bainite(LB),granular bainite(GB)and pearlite+ferrite(P+F)in a high-strength steel was studied at high temperatures using in-situ electron backscatter diffraction(EBSD).The memory effect of initial γ significantly affects the nucleation of the reverted γ in LM and GB structures,while a weak influence on that of LB and P+F structures.This results in a significant difference in γ grain size after complete austenitization,with the first two obtaining larger γ grains while the latter two are relatively small.Crystallographic analysis revealed that the reverted γ with acicular morphology(γA),most of which maintained the same orientation with the prior γ,dominated the reaustenitization behavior of LM and GB structures through preferential nucleation within γ grains and coalesced growth modes.Although globular reverted γ(γ_(G))with random orientation or large deviation from the prior γ can nucleate at the grain boundaries or within the grains,it is difficult for it to grow and play a role in segmenting and refining the prior γ due to the inhibition of γ_(A) coalescing.For LB and P+F structures,the nucleation rate of intragranular γ_(G) increases with increasing temperature,and always shows a random orientation.These γ_(G) grains can coarsen simultaneously with the intergranular γ_(G),ultimately playing a role in jointly dividing and refining the finalγgrains.Research also found that the differences in the effects of four different microstructures on revertedγnucleation are closely related to the variant selection of the matrix structure,as well as the content and size of cementite(θ).High density of block boundaries induced by weakening of variant selection and many fineθformed in the lath are the key to promoting LB structure to obtain more intragranular γ_(G) formation,as well as the important role of the large-sized θ in P+F structure.展开更多
As a hydrogen storage material,both AlH_(3)and LiNH_(2)possess a high hydrogen capacity.However,the dehydrogenated AlH_(3)can hardly absorb hydrogen under normal conditions,while LiNH_(2)will generate NH_(3)rather tha...As a hydrogen storage material,both AlH_(3)and LiNH_(2)possess a high hydrogen capacity.However,the dehydrogenated AlH_(3)can hardly absorb hydrogen under normal conditions,while LiNH_(2)will generate NH_(3)rather than H_(2)upon decomposition.In this work,we report thatthe combination of AlH_(3)and LiNH_(2)through simple ball milling leads to partial reversibility of the AlH_(3)-LiNH_(2)system and the suppression of NH_(3)liberation.The negatively charged H^(δ-)in AlH_(3)will react with the positively charged H^(δ+)in LiNH_(2)through a redox reaction to form Li_(2)NH,AlN,and H_(2)at 120-170℃.After dehydrogenation at above 270℃,Li_(3)AlN_(2)is generated,which is crucial for the reversibility of this system.The more the Li3AlN2generated,the better the reversibility of this system.The dehydrogenation capacity of AlH_(3)+2LiNH_(2)at the third cycle(3.0 wt%)is higher than that of AlH_(3)+LiNH_(2)(1.2 wt%)due to the generation of more Li3AlN2.The role of AIH_(3)/Al in the AlH_(3)-LiNH_(2)system is to fix the nitrogen into the form of AIN and Li_(3)AlN_(2)and thus suppress the liberation of NH_(3).Therefore,the synergy of AlH_(3)and LiNH_(2)leads to the reversibility of the Li-Al-NH system and the suppression of NH_(3).展开更多
Cancer multidrug resistance(MDR)impairs the therapeutic efficacy of various chemotherapeutics.Novel approaches,particularly the development of MDR reversal agents,are critically needed to address this challenge.This s...Cancer multidrug resistance(MDR)impairs the therapeutic efficacy of various chemotherapeutics.Novel approaches,particularly the development of MDR reversal agents,are critically needed to address this challenge.This study demonstrates that tenacissoside I(TI),a compound isolated from Marsdenia tenacissima(Roxb.)Wight et Arn,traditionally used in clinical practice as an ethnic medicine for cancer treatment,exhibits significant MDR reversal effects in ABCB1-mediated MDR cancer cells.TI reversed the resistance of SW620/AD300 and KBV200 cells to doxorubicin(DOX)and paclitaxel(PAC)by downregulating ABCB1 expression and reducing ABCB1 drug transport function.Mechanistically,protein arginine methyltransferase 1(PRMT1),whose expression correlates with poor prognosis and shows positive association with both ABCB1 and EGFR expressions in tumor tissues,was differentially expressed in TI-treated SW620/AD300 cells.SW620/AD300 and KBV200 cells exhibited elevated levels of EGFR asymmetric dimethylarginine(aDMA)and enhanced PRMT1-EGFR interaction compared to their parental cells.Moreover,TI-induced PRMT1 downregulation impaired PRMT1-mediated aDMA of EGFR,PRMT1-EGFR interaction,and EGFR downstream signaling in SW620/AD300 and KBV200 cells.These effects were significantly reversed by PRMT1 overexpression.Additionally,TI demonstrated resistance reversal to PAC in xenograft models without detectable toxicities.This study establishes TI's MDR reversal effect in ABCB1-mediated MDR human cancer cells through inhibition of PRMT1-mediated aDMA of EGFR,suggesting TI's potential as an MDR modulator for improving chemotherapy outcomes.展开更多
To mitigate the challenges in managing the damage level of reinforced concrete(RC)pier columns subjected to cyclic reverse loading,this study conducted a series of cyclic reverse tests on RC pier columns.By analyzing ...To mitigate the challenges in managing the damage level of reinforced concrete(RC)pier columns subjected to cyclic reverse loading,this study conducted a series of cyclic reverse tests on RC pier columns.By analyzing the outcomes of destructive testing on various specimens and fine-tuning the results with the aid of the IMK(Ibarra Medina Krawinkler)recovery model,the energy dissipation capacity coefficient of the pier columns were able to be determined.Furthermore,utilizing the calibrated damage model parameters,the damage index for each specimen were calculated.Based on the obtained damage levels,three distinct pre-damage conditions were designed for the pier columns:minor damage,moderate damage,and severe damage.The study then predicted the variations in hysteresis curves and damage indices under cyclic loading conditions.The experimental findings reveal that the displacement at the top of the pier columns can serve as a reliable indicator for controlling the damage level of pier columns post-loading.Moreover,the calibrated damage index model exhibits proficiency in accurately predicting the damage level of RC pier columns under cyclic loading.展开更多
Potassium(K)is known to enhance the catalytic performance of Fe-based catalysts in the reverse water-gas shift(rWGS)reaction,which is highly relevant during Fischer-Tropsch(FT)synthesis of CO_(2)-H_(2) mixtures.To elu...Potassium(K)is known to enhance the catalytic performance of Fe-based catalysts in the reverse water-gas shift(rWGS)reaction,which is highly relevant during Fischer-Tropsch(FT)synthesis of CO_(2)-H_(2) mixtures.To elucidate the mechanistic role of K promoter,we employed density functional theory(DFT)calculations in conjunction with microkinetic modelling for two representative surface terminations of Hägg carbide(χ-Fe_(5)C_(2)),i.e.,(010)and(510).K_(2)O results in stronger adsorption of CO_(2)and H_(2) on Hägg carbide and promotes C–O bond dissociation of adsorbed CO_(2)by increasing the electron density on Fe atoms close to the promoter oxide.The increased electron density of the surface Fe atoms results in an increased electron-electron repulsion with bonding orbitals of adsorbed CO_(2).Microkinetics simulations predict that K_(2)O increases the CO_(2)conversion during CO_(2)-FT synthesis.K_(2)O also enhances CO adsorption and dissociation,facilitating the formation of methane,used here as a proxy for hydrocarbons formation during CO_(2)-FT synthesis.CO dissociation and O removal via H_(2)O compete as the rate-controlling steps in CO_(2)-FT.展开更多
基金supported by the National Natural Science Foundation of China(Nos.62171204,62171129,62001192).
文摘We propose an optimization method based on evolutionary computation for the design of broadband high-efficiency current-biased reverse load-modulation power amplifiers(CB-RLM PAs).First,given the reverse load-modulation characteristics of CB-RLM PAs,a comprehensive objective function is proposed that combines multi-state impedance trajectory constraints with in-band performance deviations.For the saturation and 6 dB power back-off(PBO)states,approximately optimal impedance regions on the Smith chart are derived using impedance constraint circles based on load-pull simulations.These regions are used together with in-band performance deviations(e.g.,saturated efficiency,6 dB PBO efficiency,and saturated output power)for matching network optimization and design.Second,a multi-objective evolutionary algorithm based on decomposition with adaptive weights,neighborhood,and global replacement is integrated with harmonic balance simulations to optimize design parameters and evaluate performance.Finally,to validate the proposed method,a broadband CB-RLM PA operating from 0.6 to 1.8 GHz is designed and fabricated.Measurement results show that the efficiencies at saturation,6 dB PBO,and 8 dB PBO all exceed 43.6%,with saturated output power being maintained at 40.9–41.5 dBm,which confirms the feasibility and effectiveness of the proposed broadband high-efficiency CB-RLM PA optimization and design approach.
基金supported by the grants from National Key R&D Program of China(No.2022YFA1104800)Shenzhen Science and Technology Program(No.JCYJ20210324124214038)+4 种基金National Natural Science Foundation of China(Nos.52072418,82300016)Natural Science Foundation of Guangdong Province(No.2023A1515140072)Shenzhen Key Laboratory of Neural Cell Reprogramming and Drug Research,Social Development Science and Technology Key Project of Dongguan(No.20231800940512)the National Medical Research Council(NMRC,No.23-0740-A0001)the Ministry of Education(MOE,No.T2EP10222-0002)of Singapore.
文摘Lysine-targeting reversible covalent inhibitors,particularly salicylaldehyde-based compounds such as the Food and Drug Administration(FDA)-approved drug Voxelotor,exhibit significant therapeutic potential but are limited by challenges including instability and off-target effects.To overcome these limitations in kinase inhibitor A5,we devised a pH-responsive prodrug strategy by masking its reactive aldehyde group with an acid-labile hydrazone linkage and enhancing intracellular delivery through conjugation with FK506.The optimized prodrug demonstrated robust antitumor efficacy in K562 tumor-bearing mice.Furthermore,the incorporation of the photosensitizer chlorin e6(Ce6)led to the formation of self-assembled nanoparticles(AKNP),which not only improved physiological stability and prolonged tumor retention but also enabled light-triggered release of A5 in conjunction with photodynamic therapy(PDT).Our study thus presents a promising prodrug self-assembly strategy that combines the on-demand release of a novel lysine-targeting,reversible covalent kinase inhibitor with PDT in clinical cancer therapy.
基金supported by the Wellcome Trust(grant No.103852).
文摘The nervous system function requires a precise but plastic neural architecture.The neuronal shape dictates how neurons interact with each other and with other cells,being the morphology of dendrites and axons the central determinant of the functional properties of neurons and neural circuits.The topological and structural morphology of axons and dendrites defines and determines how synapses are conformed.The morphological diversity of axon and dendrite arborization governs the neuron’s inputs,synaptic integration,neuronal computation,signal transmission,and network circuitry,hence defining the particular connectivity and function of the different brain areas.
基金financially supported by the supported by Shandong Provincial Natural Science Foundation(ZR2024MB108)Taishan Young Scholar Program(tsqn202312312)Excellent Young Scholars of the Shandong Provincial Natural Science Foundation(Overseas)(2023HWYQ-112)。
文摘Conversion-type electrode materials hold significant promise for potassium-ion batteries(PIBs)due to their high theoretical capacities,yet their practical deployment is hindered by sluggish kinetics and irreversible structural degradation.To overcome these limitations,we propose a rationally engineered nanoreactor architecture that stabilizes defect-rich MoS_(2)via interlayer incorporation of a carbon monolayer,followed by encapsulation within a nitrogen-doped carbon shell,forming a MoSSe@NC heterostructure.This tailored structure synergistically accelerates both K^(+)diffusion kinetics and electron transfer,enabling unprecedented rate performance(107 mAh g^(-1)at 10 Ag^(-1))and ultralong cyclability(86.5%capacity retention after 1200 cycles at 3 A g^(-1)).Mechanistic insights reveal a distinctive“adsorption-conversion”pathway,where sulfur vacancies on exposed S-Mo-S basal planes act as preferential K^(+)adsorption sites,effectively suppressing parasitic phase transitions during intercalation.In situ X-ray diffraction and transmission electron microscopy corroborate the structural reversibility of the conversion reaction,with the carbon matrix dynamically accommodating strain while preserving electrode integrity.This work not only advances the understanding of defect-driven interfacial chemistry in conversion-type materials but also provides a versatile strategy for designing high-performance anodes in next-generation PIBs through heterostructure engineering.
文摘BACKGROUND The optimal surgical approach for patients with primary glenohumeral osteoarthritis(GHOA)and an intact rotator cuff remains debated.While anatomic total shoulder arthroplasty(TSA)has traditionally been favoured,reverse TSA(RTSA)is increasingly utilized.AIM To systematically compare the outcomes of RTSA and TSA in this specific patient population.METHODS A systematic review and meta-analysis were conducted in accordance with PRISMA guidelines.Retrospective comparative studies evaluating RTSA and TSA in patients with GHOA and intact rotator cuff were included.Key outcomes assessed included complication and reoperation rates,patient-reported outcome measures(PROMs),and range of motion.Risk of bias was assessed using the Risk of Bias in Non-randomized Studies of Interventions tool.RESULTS Twelve studies encompassing 1608 patients(580 RTSA,1028 TSA)met inclusion criteria.RTSA was associated with a lower reoperation rate compared to TSA[odds ratio=0.37;95%confidence interval(CI):0.14-0.94;P value=0.04],while no significant difference in overall complication rates was observed(odds ratio=0.47;95%CI:0.19-1.16;P value=0.10).RTSA patients showed superior outcomes in University of California Los Angeles,Simple Shoulder Test,and Shoulder Pain and Disability Index scores;however,the differences did not exceed the minimal clinically important difference.TSA patients had significantly better external rotation(mean difference=-9.0°;95%CI:-13.21 to-5.02;P value<0.0001).No significant differences were found in other range of motion measures or satisfaction scores.The overall methodological quality of included studies was moderate to serious.CONCLUSION In patients with GHOA and an intact rotator cuff,RTSA may offer comparable or improved outcomes to TSA with lower reoperation rates and similar complication profiles.Functional outcomes favour RTSA in certain patientreported outcome measures,while TSA retains an advantage in external rotation.Surgical decision-making should remain individualized based on patient characteristics and functional demands.
基金supported by the National Natural Science Foundation of China(Grant Nos.52025053 and 52235006)the Jilin Provincial Scientific and Technological Development Program(20220204119YY)the Natural Science Foundation of Shandong Province(ZR2023ME154)。
文摘Ceramic 4D printing,which integrates dynamic deformation with additive manufacturing,demonstrates significant potential in intelligent manufacturing,on-demand shaping of complex structures,and multifunctional device development.Its core advantage lies in endowing materials with environmentally responsive dynamic deformation capabilities.However,current technologies still face limitations in responsiveness,reversibility,and mechanical performance.To address these challenges,this study proposes a programmable ceramic precursor system based on synergistic reinforcement of phase-separating hydrogels and shape memory polymers,combined with a nano-ceramic particle enhancement strategy.Using stereolithography 3D printing,high-precision fabrication of complex structures was achieved.By adjusting precursor composition,programming time,and structural thickness,the phase-separation kinetics-driven delayed recovery mechanism was elucidated,enabling precise control over recovery onset time.Furthermore,the thermal response mechanism of the precursor materials is explored,along with their potential for multi-shape transformation in biomedical applications,which is further extended to shape memory polymer systems.By employing a layered printing strategy,the autonomous reversible deformation of ceramic precursors is realized,providing new possibilities for specific applications.
基金funded by University of Transport and Communications(UTC)under grant number T2025-CN-004.
文摘Reversible data hiding(RDH)enables secret data embedding while preserving complete cover image recovery,making it crucial for applications requiring image integrity.The pixel value ordering(PVO)technique used in multi-stego images provides good image quality but often results in low embedding capability.To address these challenges,this paper proposes a high-capacity RDH scheme based on PVO that generates three stego images from a single cover image.The cover image is partitioned into non-overlapping blocks with pixels sorted in ascending order.Four secret bits are embedded into each block’s maximum pixel value,while three additional bits are embedded into the second-largest value when the pixel difference exceeds a predefined threshold.A similar embedding strategy is also applied to the minimum side of the block,including the second-smallest pixel value.This design enables each block to embed up to 14 bits of secret data.Experimental results demonstrate that the proposed method achieves significantly higher embedding capacity and improved visual quality compared to existing triple-stego RDH approaches,advancing the field of reversible steganography.
基金financially supported by the Nation Key R&D Program China(2018YFA0703200)the Key Research and Development Program of Hubei Province(2022BAA026)+1 种基金the National Natural Science Foundation of China(51772110)the Open Research Fund(2024JYBKF01)of Key Laboratory of Material Chemistry for Energy Conversion and Storage(HUST),Ministry of Education。
文摘Sluggish kinetics coupled with parasitic shuttling reactions are pivotal challenges hindering the performance of lithium-sulfur(Li-S)batteries.Improving areal capacity and cyclability of Li-S batteries can be achieved by addressing these challenges.A composite sulfur host material is synthesized herein by in situ anchoring ultrafine cobalt-iron phosphide nanoparticles(5-7 nm)onto a hollow mesoporous carbon sphere(HMCS)framework.This strategy achieved exceptional spatial restriction and a high density of catalytically active sites through the encapsulation of sulfur within a hollow-structured framework.Specifically,HMCS expedites rapid Li_(2)S nucleation kinetics,while CoFeP facilitates robust Li_(2)S dissolution kinetics by mitigating decomposition barriers.This synergistic integration equips CoFeP@HMCS with robust bi-directional catalytic activity,significantly promoting interracial charge-transfer,facilitate sulfu r multistep catalytic conversion,and inhibiting shuttling.Consequently,the battery exhibits excellent rate performance(991 mA h g^(-1) at 5.0 C)and retains a high areal capacity of 6.06 mA h cm^(-2) after 200 cycles under a high areal sulfur loading of 8.2 mg cm^(-2) but a low electrolyte/sulfur ratio of 4.8μL mg^(-1).This work contributes to enhancing the practical specific capacity of lithium-sulfur batteries and deepens the understanding of catalysts enabling bidirectional electrocatalytic sulfur conversion.
基金supported by Science and Technology Project of the headquarters of the State Grid Corporation of China(No.5500-202324492A-3-2-ZN).
文摘To enhance power flow regulation in scenarios involving large-scale renewable energy transmission via high-voltage direct current(HVDC)links and multi-infeed DC systems in load-center regions,this paper proposes a hybrid modular multilevel converter–capacitor-commutated line-commutated converter(MMC-CLCC)HVDC transmission system and its corresponding control strategy.First,the system topology is constructed,and a submodule configuration method for the MMC—combining full-bridge submodules(FBSMs)and half-bridge submodules(HBSMs)—is proposed to enable direct power flow reversal.Second,a hierarchical control strategy is introduced,includingMMCvoltage control,CLCC current control,and a coordinationmechanism,along with the derivation of the hybrid system’s power flow reversal characteristics.Third,leveraging the CLCC’s fast current regulation and theMMC’s negative voltage control capability,a coordinated power flow reversal control strategy is developed.Finally,an 800 kV MMC-CLCC hybrid HVDC system is modeled in PSCAD/EMTDC to validate the power flow reversal performance under a high proportion of full-bridge submodule configuration.Results demonstrate that the proposed control strategy enables rapid(1-s transition)and smooth switching of bidirectional power flow without modifying the structure of primary equipment:the transient fluctuation ofDC voltage from the rated value(UdcN)to themaximumreverse voltage(-kUdcN)is less than 5%;the DC current strictly follows the preset characteristic curve with a deviation of≤3%;the active power reverses continuously,and the system maintains stable operation throughout the reversal process.
文摘BACKGROUND Posterior reversible encephalopathy syndrome(PRES)is a complex neurological disorder characterized by symptoms such as headaches,seizures,confusion,and visual disturbances.The pathophysiology of PRES involves endothelial dysfunction,disrupted cerebral autoregulation,and resulting vasogenic edema.Hypertension and other factors that alter cerebral autoregulation are critical in its development.Corticosteroids,widely used for their anti-inflammatory and immunosuppressive properties,play a controversial role in PRES.AIM To elucidate the dual role of corticosteroids in the context of PRES by critically evaluating the existing literature.Specifically,it seeks to assess the results of PRES induced by corticosteroid therapy and the efficacy and safety of corticosteroids in the treatment of PRES.By synthesizing case reports and series,this review aims to provide a comprehensive understanding of the mechanisms,clinical presentations,and management strategies associated with corticosteroid-related PRES.METHODS The review was carried out according to the PRISMA guidelines.The databases searched included Science Direct,PubMed,and Hinari.The search strategy encompassed terms related to corticosteroids and PRES.Studies were included if they were peer-reviewed articles examining corticosteroids in PRES,excluding non-English publications,reviews,and editorials.Data on patient demographics,clinical characteristics,imaging findings,corticosteroid regimens,and outcomes were extracted.The risk of bias was evaluated using the Joanna Briggs Institute tool for case reports.RESULTS A total of 56 cases of PRES(66.1%women,33.9%men)potentially induced by corticosteroids and 14 cases in which corticosteroids were used to treat PRES were identified.Cases of PRES reportedly caused by corticosteroids showed a mean age of approximately 25.2 years,with seizures,headaches,hypertension,and visual disturbances being common clinical sequelae.Magnetic resonance findings typically revealed vasogenic edema in the bilateral parieto-occipital lobes.High-dose or prolonged corticosteroid therapy was a significant risk factor.On the contrary,in the treatment cases,corticosteroids were associated with positive outcomes,including resolution of vasogenic edema and stabilization of symptoms,particularly in patients with underlying inflammatory or autoimmune diseases.CONCLUSION Corticosteroids have a dual role in PRES,capable of both inducing and treating the condition.The current body of literature suggests that corticosteroids may play a greater role as a precipitating agent of PRES rather than treating.Corticosteroids may induce PRES through hypertension and subsequent increased cerebral blood flow and loss of autoregulation.Corticosteroids may aid in the management of PRES:(1)Enhancing endothelial stability;(2)Antiinflammatory properties;and(3)Improving blood-brain barrier integrity.Mechanisms which may reduce or mitigate vasogenic edema formation.
文摘Pseudoephedrine (PSE) is a widely used nasal decongestant. A review by the European Medicines Agency has reported that PSE may be associated with risks of posterior reversible encephalopathy syndrome (PRES) and reversible cerebral vasoconstriction syndrome (RCVS). PRES and RCVS are rare but serious conditions that affect cerebral blood flow. This review discusses the pharmacology of PSE and potential risks for PRES and RCVS and concludes that considering the common use of PSE, with over 70 million packs of PSE taken each year in the European Union and the United Kingdom, and the rare occurrence of PRES and RCVS, that the risks of developing PRES/RCVS on exposure to PSE are likely to be very low.
文摘Dear Editor,Posterior reverse encephalopathy syndrome(PRES),manifests as a confusional state/delirium,convulsion,or acute blindness which illustrates in magnetic resonance imaging(MRI)typical bilateral white matter lesions.These clinical and radiological changes are reversible in two to three weeks,usually generated by acute hypertension,preeclampsia,eclampsia,immunosuppression,septicemia,and end-stage renal disease.PRES is commonly diagnosed in patients in their thirties.
文摘Dear Editor,In this case,we discuss a teenager who experienced severe eye pain and elevated intraocular pressure(IOP)caused by reverse pupillary block,which was successfully resolved using Neodymium-doped yttrium aluminum garnet(Nd:YAG)laser peripheral iridotomy(LPI).
基金supported by the National Natural Science Foundation of China(No.52377212 and 51877173)program of Beijing Huairou Laboratory(ZD2022006A)+2 种基金the Key R&D Project of Shaanxi Province(2023-YBGY-057)the State Key Laboratory of Electrical Insulation and Power Equipment(EIPE22314,EIPE22306)the Natural Science Basic Research Program of Shaanxi(No.2023-JC-QN-0483).
文摘Reversible solid oxide cells(RSOCs)are capable of converting various energy resources,between electricity and chemical fuels,with high efficiency and flexibility,making them suitable for grid balancing and renewable energy consumption.However,the practical application of RSOCs is still limited by the insufficient activity and stability of the electrodes in different operating modes.Herein,a highly efficient symmetrical electrode composed of La_(0.3)Sr_(0.6)Ti_(0.1)Co_(0.2)Fe_(0.7)O_(3-δ)(LSTCF)nanofibers and in situ exsolved Co_(3)Fe_(7) nanoparticles is developed for boosting the performance of RSOCs.The reversible phase transition,high activity and stability of the electrode have been confirmed by a combination of experimental(e.g.,transmission electron microscopy and X-ray absorption fine structure)and computational studies.Electrolyte-supported RSOCs with the symmetrical electrode demonstrate excellent catalytic activity and stability,achieving a high peak power density of 0.98 W cm^(-2)in the fuel cell mode using H_(2)as the fuel(or 0.53 W cm^(-2)using CH_(4)as the fuel)and a high current density of 1.09 A cm^(-2) at 1.4 V in the CO_(2)electrolysis mode(or 1.03 A cm^(-2)at 1.3 V for H_(2)O electrolysis)at 800℃while maintaining excellent durability for over 100 h.
基金supported by Fundamental Research Funds for the Central Universities(2023KYJD1008)the Science Research Projects of the Anhui Higher Education Institutions of China(2022AH051582).
文摘Reversible solid oxide cell(RSOC)is a new energy conversion device with significant applications,especially for power grid peaking shaving.However,the reversible conversion process of power generation/energy storage poses challenges for the performance and stability of air electrodes.In this work,a novel high-entropy perovskite oxide La_(0.2)Pr_(0.2)Gd_(0.2)Sm_(0.2)Sr_(0.2)Co_(0.8)Fe_(0.2)O_(3−δ)(HE-LSCF)is proposed and investigated as an air electrode in RSOC.The electrochemical behavior of HE-LSCF was studied as an air electrode in both fuel cell and electrolysis modes.The polarization impedance(Rp)of the HE-LSCF electrode is only 0.25Ω·cm^(2) at 800℃ in an air atmosphere.Notably,at an electrolytic voltage of 2 V and a temperature of 800℃,the current density reaches up to 1.68 A/cm^(2).The HE-LSCF air electrode exhibited excellent reversibility and stability,and its electrochemical performance remains stable after 100 h of reversible operation.With these advantages,HE-LSCF is shown to be an excellent air electrode for RSOC.
基金financially supported by the National Natural Science Foundation of China(Nos.52271089 and 52001023)the Basic Research and Application Basic Research Foundation of Guangdong Province(Nos.2022A1515240016 and 2023B1515250006)the Fundamental Research Funds for the Central Universities(No.FRF-BD-23-01).
文摘The austenite(γ)reversely transformed from lath martensite(LM),lath bainite(LB),granular bainite(GB)and pearlite+ferrite(P+F)in a high-strength steel was studied at high temperatures using in-situ electron backscatter diffraction(EBSD).The memory effect of initial γ significantly affects the nucleation of the reverted γ in LM and GB structures,while a weak influence on that of LB and P+F structures.This results in a significant difference in γ grain size after complete austenitization,with the first two obtaining larger γ grains while the latter two are relatively small.Crystallographic analysis revealed that the reverted γ with acicular morphology(γA),most of which maintained the same orientation with the prior γ,dominated the reaustenitization behavior of LM and GB structures through preferential nucleation within γ grains and coalesced growth modes.Although globular reverted γ(γ_(G))with random orientation or large deviation from the prior γ can nucleate at the grain boundaries or within the grains,it is difficult for it to grow and play a role in segmenting and refining the prior γ due to the inhibition of γ_(A) coalescing.For LB and P+F structures,the nucleation rate of intragranular γ_(G) increases with increasing temperature,and always shows a random orientation.These γ_(G) grains can coarsen simultaneously with the intergranular γ_(G),ultimately playing a role in jointly dividing and refining the finalγgrains.Research also found that the differences in the effects of four different microstructures on revertedγnucleation are closely related to the variant selection of the matrix structure,as well as the content and size of cementite(θ).High density of block boundaries induced by weakening of variant selection and many fineθformed in the lath are the key to promoting LB structure to obtain more intragranular γ_(G) formation,as well as the important role of the large-sized θ in P+F structure.
基金financially supported by the National Natural Science Foundation of China(Nos.22379030,52001079,52261038)the Science and Technology Department of Guangxi Zhuang Autonomous(Nos.2024JJG160001,GuiKeAD21238022)the Innovation Project of Guangxi Graduate Education(No.YCBZ2023011)
文摘As a hydrogen storage material,both AlH_(3)and LiNH_(2)possess a high hydrogen capacity.However,the dehydrogenated AlH_(3)can hardly absorb hydrogen under normal conditions,while LiNH_(2)will generate NH_(3)rather than H_(2)upon decomposition.In this work,we report thatthe combination of AlH_(3)and LiNH_(2)through simple ball milling leads to partial reversibility of the AlH_(3)-LiNH_(2)system and the suppression of NH_(3)liberation.The negatively charged H^(δ-)in AlH_(3)will react with the positively charged H^(δ+)in LiNH_(2)through a redox reaction to form Li_(2)NH,AlN,and H_(2)at 120-170℃.After dehydrogenation at above 270℃,Li_(3)AlN_(2)is generated,which is crucial for the reversibility of this system.The more the Li3AlN2generated,the better the reversibility of this system.The dehydrogenation capacity of AlH_(3)+2LiNH_(2)at the third cycle(3.0 wt%)is higher than that of AlH_(3)+LiNH_(2)(1.2 wt%)due to the generation of more Li3AlN2.The role of AIH_(3)/Al in the AlH_(3)-LiNH_(2)system is to fix the nitrogen into the form of AIN and Li_(3)AlN_(2)and thus suppress the liberation of NH_(3).Therefore,the synergy of AlH_(3)and LiNH_(2)leads to the reversibility of the Li-Al-NH system and the suppression of NH_(3).
基金supported by the National Natural Science Foundation of China(Nos.82274211 and 82474190)the Natural Science Foundation of Tianjin(Nos.24JCZDJC00120 and 24PTLYHZ00280)Liaoning Provincial Department of Education Basic Research Projects for Higher Education Institutions(No.LJ212510163021)。
文摘Cancer multidrug resistance(MDR)impairs the therapeutic efficacy of various chemotherapeutics.Novel approaches,particularly the development of MDR reversal agents,are critically needed to address this challenge.This study demonstrates that tenacissoside I(TI),a compound isolated from Marsdenia tenacissima(Roxb.)Wight et Arn,traditionally used in clinical practice as an ethnic medicine for cancer treatment,exhibits significant MDR reversal effects in ABCB1-mediated MDR cancer cells.TI reversed the resistance of SW620/AD300 and KBV200 cells to doxorubicin(DOX)and paclitaxel(PAC)by downregulating ABCB1 expression and reducing ABCB1 drug transport function.Mechanistically,protein arginine methyltransferase 1(PRMT1),whose expression correlates with poor prognosis and shows positive association with both ABCB1 and EGFR expressions in tumor tissues,was differentially expressed in TI-treated SW620/AD300 cells.SW620/AD300 and KBV200 cells exhibited elevated levels of EGFR asymmetric dimethylarginine(aDMA)and enhanced PRMT1-EGFR interaction compared to their parental cells.Moreover,TI-induced PRMT1 downregulation impaired PRMT1-mediated aDMA of EGFR,PRMT1-EGFR interaction,and EGFR downstream signaling in SW620/AD300 and KBV200 cells.These effects were significantly reversed by PRMT1 overexpression.Additionally,TI demonstrated resistance reversal to PAC in xenograft models without detectable toxicities.This study establishes TI's MDR reversal effect in ABCB1-mediated MDR human cancer cells through inhibition of PRMT1-mediated aDMA of EGFR,suggesting TI's potential as an MDR modulator for improving chemotherapy outcomes.
基金supported by National Natural Science Foundation of China(Project No.51878156)EPC Innovation Consulting Project for Longkou Nanshan LNG Phase I Receiving Terminal(Z2000LGENT0399).
文摘To mitigate the challenges in managing the damage level of reinforced concrete(RC)pier columns subjected to cyclic reverse loading,this study conducted a series of cyclic reverse tests on RC pier columns.By analyzing the outcomes of destructive testing on various specimens and fine-tuning the results with the aid of the IMK(Ibarra Medina Krawinkler)recovery model,the energy dissipation capacity coefficient of the pier columns were able to be determined.Furthermore,utilizing the calibrated damage model parameters,the damage index for each specimen were calculated.Based on the obtained damage levels,three distinct pre-damage conditions were designed for the pier columns:minor damage,moderate damage,and severe damage.The study then predicted the variations in hysteresis curves and damage indices under cyclic loading conditions.The experimental findings reveal that the displacement at the top of the pier columns can serve as a reliable indicator for controlling the damage level of pier columns post-loading.Moreover,the calibrated damage index model exhibits proficiency in accurately predicting the damage level of RC pier columns under cyclic loading.
文摘Potassium(K)is known to enhance the catalytic performance of Fe-based catalysts in the reverse water-gas shift(rWGS)reaction,which is highly relevant during Fischer-Tropsch(FT)synthesis of CO_(2)-H_(2) mixtures.To elucidate the mechanistic role of K promoter,we employed density functional theory(DFT)calculations in conjunction with microkinetic modelling for two representative surface terminations of Hägg carbide(χ-Fe_(5)C_(2)),i.e.,(010)and(510).K_(2)O results in stronger adsorption of CO_(2)and H_(2) on Hägg carbide and promotes C–O bond dissociation of adsorbed CO_(2)by increasing the electron density on Fe atoms close to the promoter oxide.The increased electron density of the surface Fe atoms results in an increased electron-electron repulsion with bonding orbitals of adsorbed CO_(2).Microkinetics simulations predict that K_(2)O increases the CO_(2)conversion during CO_(2)-FT synthesis.K_(2)O also enhances CO adsorption and dissociation,facilitating the formation of methane,used here as a proxy for hydrocarbons formation during CO_(2)-FT synthesis.CO dissociation and O removal via H_(2)O compete as the rate-controlling steps in CO_(2)-FT.
