[Background]High harmonic cavities are widely used in electron storage rings to lengthen thebunch,lower the bunch peak current,thereby reducing the IBS effect,enhancing the Touschek lifetime,as well asproviding Landau...[Background]High harmonic cavities are widely used in electron storage rings to lengthen thebunch,lower the bunch peak current,thereby reducing the IBS effect,enhancing the Touschek lifetime,as well asproviding Landau damping,which is particularly important for storage rings operating with ultra-low emittance or atlow beam energy.[Purpose]To further increase the bunch length without additional hardware costs,the phasemodulation in a dual-RF system is considered.[Methods]In this paper,turn-by-turn simulations incorporating randomsynchrotron radiation excitation are conducted,and a brief analysis is presented to explain the bunch lengtheningmechanism.[Results]Simulation results reveal that the peak current can be further reduced,thereby mitigating IBSeffects and enhancing the Touschek lifetime.Although the energy spread increases,which tends to reduce thebrightness of higher-harmonic radiation from the undulator,the brightness of the fundamental harmonic can,in fact,beimproved.展开更多
The accurate establishment of a ferrite transformation start temperature model is crucial to design a reasonable controlled rolling process and ensure uniform microstructure in aluminum bearing dual-phase steel.The me...The accurate establishment of a ferrite transformation start temperature model is crucial to design a reasonable controlled rolling process and ensure uniform microstructure in aluminum bearing dual-phase steel.The measurements of the expansion-temperature curves of aluminum bearing dual-phase steel under continuous cooling and isothermal conditions are presented,utilizing a dynamic transformation dilatometer experiment.Based on these expansion-temperature curves,the start temperature and incubation time of ferrite transformation were determined,elucidating the influence of process parameters on both the incubation time and the start temperature of ferrite transformation.By integrating metallurgical principles with measured incubation time of ferrite transformation,and considering the effects of temperature and strain,a fitting model for the variation in volume free energy during ferrite nucleation was derived.Building upon this foundation,a high-precision incubation time of ferrite transformation mathematical model for the experimental steel was established.To more accurately calculate the start temperature of ferrite transformation under continuous cooling conditions,the Scheil’s additivity rule was modified to account for the effects of deformation and cooling rate.The results indicate that the modification coefficient decreases with increasing the cooling rate and strain,thereby significantly improving the accuracy of calculating the starting temperature of ferrite transformation using the modified additivity rule.展开更多
While reinforcement learning-based underwater acoustic adaptive modulation shows promise for enabling environment-adaptive communication as supported by extensive simulation-based research,its practical performance re...While reinforcement learning-based underwater acoustic adaptive modulation shows promise for enabling environment-adaptive communication as supported by extensive simulation-based research,its practical performance remains underexplored in field investigations.To evaluate the practical applicability of this emerging technique in adverse shallow sea channels,a field experiment was conducted using three communication modes:orthogonal frequency division multiplexing(OFDM),M-ary frequency-shift keying(MFSK),and direct sequence spread spectrum(DSSS)for reinforcement learning-driven adaptive modulation.Specifically,a Q-learning method is used to select the optimal modulation mode according to the channel quality quantified by signal-to-noise ratio,multipath spread length,and Doppler frequency offset.Experimental results demonstrate that the reinforcement learning-based adaptive modulation scheme outperformed fixed threshold detection in terms of total throughput and average bit error rate,surpassing conventional adaptive modulation strategies.展开更多
Aqueous zinc-ion batteries(AZIBs)offer promising safety and affordability,but suffer from dendritic Zn growth and parasitic side reactions at the electrode-electrolyte interface.Herein,we construct a dual-region inter...Aqueous zinc-ion batteries(AZIBs)offer promising safety and affordability,but suffer from dendritic Zn growth and parasitic side reactions at the electrode-electrolyte interface.Herein,we construct a dual-region interfacial modulation framework by molecularly reconfiguring the Helmholtz double layer via trace methyl methacrylate(MMA).Exploiting its amphiphilic and functionally asymmetric architecture,MMA enables a coordinated interfacial reconstruction that disrupts Zn^(2+)solvation in the outer Helmholtz plane,builds a chemisorbed coordination layer in the inner plane,and modulates local interfacial chemistry with spatial precision.This dualregion regulation collectively suppresses water reactivity,facilitates Zn^(2+)desolvation,and drives crystallo-graphically preferred deposition along the(101)plane,promoting lateral growth and mitigating dendrite for-mation.As a result,symmetric Zn||Zn cells exhibit over 4200 h of stable cycling at 1 mA cm^(-2) and maintain 1100 h of operation at 2 mA cm^(-2),even at 0℃.Zn||Ti half-cells achieve a Coulombic efficiency of 99.83%,while Zn||NH_(4)V_(4)O_(10) full cells deliver 93.92%capacity retention after 400 cycles at 2 A g^(-1),and preserve 85.3%after 300 cycles at 0℃.This work demonstrates a scalable,mechanism-driven electrolyte design paradigm for dendrite-free and high-performance aqueous Zn metal batteries.展开更多
Epidemiological studies have highlighted an association between periodontitis and osteoporosis.However,the mechanism underlining this association remains unclear.Here,we revealed significant differences in the salivar...Epidemiological studies have highlighted an association between periodontitis and osteoporosis.However,the mechanism underlining this association remains unclear.Here,we revealed significant differences in the salivary microbiota between periodontally healthy individuals and periodontitis patients,with periodontitis patients exhibiting increased salivary microbiota diversity and an elevated abundance of pathogenic bacteria.Using an ovariectomized(OVX) mouse model,we demonstrated that the salivary microbiota from periodontitis patients exacerbated bone destruction by modulating the gut microbiota.Metabolomic analysis revealed that the periodontitis-associated salivary microbiota suppressed tryptophan metabolism.The tryptophan metabolite indole-3-lactic acid(ILA) directly inhibited osteoclast formation and differentiation.In OVX mice treated with periodontitis salivary microbiota,supplementation with ILA effectively suppressed osteoclastogenesis and alleviated the detrimental effects of periodontitis-associated salivary microbiota on systemic bones.In summary,our data demonstrate that periodontitis can affect systemic bone metabolism via the oral-gut axis and that ILA supplementation serves as a potential therapeutic option to mitigate these adverse effects.展开更多
Modulations of mitochondrial dysfunction,which involve a series of dynamic processes such as mitochondrial biogenesis,mitochondrial fusion and fission,mitochondrial transport,mitochondrial autophagy,mitochondrial apop...Modulations of mitochondrial dysfunction,which involve a series of dynamic processes such as mitochondrial biogenesis,mitochondrial fusion and fission,mitochondrial transport,mitochondrial autophagy,mitochondrial apoptosis,and oxidative stress,play an important role in the onset and progression of stroke.With a better understanding of the critical role of mitochondrial dysfunction modulations in post-stroke neurological injury,these modulations have emerged as a potential target for stroke prevention and treatment.Additionally,since effective treatments for stroke are extremely limited and natural products currently offer some outstanding advantages,we focused on the findings and mechanisms of action related to the use of natural products for targeting mitochondrial dysfunction in the treatment of stroke.Natural products achieve neuroprotective through multi-target regulation of mitochondrial dysfunction encompassing the following processes:(1)Mitochondrial biogenesis:Cordyceps and hydroxysafflor yellow A activate the peroxisome proliferator-activated receptor gamma coactivator 1-alpha/nuclear respiratory factor pathway,promote mitochondrial DNA replication and respiratory chain protein synthesis,and thereby restore energy supply in the ischemic penumbra.(2)Mitochondrial dynamics balance:Ginsenoside Rb3 promotes Opa1-mediated neural stem cell migration and diffusion for recovery of damaged brain tissue.(3)Mitochondrial autophagy:Gypenoside XVII selectively eliminates damaged mitochondria via the phosphatase and tensin homolog-induced kinase 1/Parkin pathway and blocks reactive oxygen species and the NOD-like receptor protein 3 inflammasome cascade,thereby alleviating blood-brain barrier damage.(4)Anti-apoptotic mechanisms:Ginkgolide K inhibits Bax mitochondrial translocation and downregulates caspase-3/9 activity,reducing neuronal programmed death induced by ischemia-reperfusion.(5)Oxidative stress regulation:Scutellarin exerts antioxidant properties and improves neurological function by modulating the extracellular signal-regulated kinase 5-Kruppel-like factor 2-endothelial nitric oxide synthase signaling pathway.(6)Intercellular mitochondrial transport:Neuroprotective effects of Chrysophanol are associated with accelerated mitochondrial transfer from astrocytes to neurons.Existing studies have confirmed that natural products exhibit neuroprotective effects through multidimensional interventions targeting mitochondrial dysfunction in both ischemic and hemorrhagic stroke models.However,their clinical translation still faces challenges,such as the difficulty in standardization due to component complexity,insufficient cross-regional clinical data,and the lack of long-term safety evaluations.Future research should aim to integrate new technologies,such as single-cell sequencing and organoid models,to deeply explore the mitochondria-targeting mechanisms of natural products and validate their efficacy through multicenter clinical trials,providing theoretical support and translational pathways for the development of novel anti-stroke drugs.展开更多
Diatomic metasurfaces designed for interferometric mechanisms possess significant potential for the multidimensional manipulation of electromagnetic waves,including control over amplitude,phase,frequency,and polarizat...Diatomic metasurfaces designed for interferometric mechanisms possess significant potential for the multidimensional manipulation of electromagnetic waves,including control over amplitude,phase,frequency,and polarization.Geometric phase profiles with spin-selective properties are commonly associated with wavefront modulation,allowing the implementation of conjugate strategies within orthogonal circularly polarized channels.Simultaneous control of these characteristics in a single-layered diatomic metasurface will be an apparent technological extension.Here,spin-selective modulation of terahertz(THz)beams is realized by assembling a pair of meta-atoms with birefringent effects.The distinct modulation functions arise from geometric phase profiles characterized by multiple rotational properties,which introduce independent parametric factors that elucidate their physical significance.By arranging the key parameters,the proposed design strategy can be employed to realize independent amplitude and phase manipulation.A series of THz metasurface samples with specific modulation functions are characterized,experimentally demonstrating the accuracy of on-demand manipulation.This research paves the way for all-silicon meta-optics that may have great potential in imaging,sensing and detection.展开更多
Fracture strain becomes critical for the local formability and crash performance of carbody components when the tensile strength exceeds 1000 MPa.Regrettably,high-strength quenching and partitioning(Q&P)steels and...Fracture strain becomes critical for the local formability and crash performance of carbody components when the tensile strength exceeds 1000 MPa.Regrettably,high-strength quenching and partitioning(Q&P)steels and dual-phase(DP)steels always focus on improving the tensile ductility for stretch formability,while ignoring their limited fracture strain.In this work,we explored a novel strategy,i.e.,developing a high fracture strain ferrite-martensite dual-phase steel(HFS-DP)maintaining good strength–ductility balance by suppressing intense strain localization during deformation and enhancing martensite deformability via microstructure design including grain refinement,nano-precipitate hardening in soft ferrite phase,low-carbon and high fraction martensite.HFS-DP demonstrates a remarkable 26%and 47%improvement in tensile ductility and fracture strain,respectively,compared to commercial DP1180 steel with similar ultimate tensile strength.Furthermore,HFS-DP also exhibits a substantial 39%improvement in fracture strain compared to retained austenite-involved commercial QP1180 steel.The detailed processes of strain partitioning,strain localization,and damage formation during deformation were revealed through in-situ scanning electron microscopy(SEM)observation combined with digital image correlation(DIC).The results indicate that the excellent coordinated deformation between ferrite and martensite,coupled with microstructure refinement,effectively suppresses intense strain localization.Moreover,the excellent martensite deformability resulting from the low carbon content also aids in retarding crack formation.This combination effectively suppresses damage initiation and development during deformation,therefore the fracture strain is significantly improved.This study not only contributes to a deeper understanding of the strain localization and damage process during tensile deformation of DP steels,but also provides a new perspective on designing ultrahigh strength steels with high ductility and fracture strain.展开更多
In this study,a novel strategy for developingα+βdual-phase titanium alloys with low Young's modulus and high yield strength was proposed,and a Ti-15Nb-5Zr-4Sn-1 Fe alloy was developed through theoretical composi...In this study,a novel strategy for developingα+βdual-phase titanium alloys with low Young's modulus and high yield strength was proposed,and a Ti-15Nb-5Zr-4Sn-1 Fe alloy was developed through theoretical composition design and microstructure manipulation.After hot-rolling and subsequent annealing,a high volume fraction of ultrafine grainedαphase embedded in metastableβ-matrix was formed in the microstructure as intended.Consequently,this alloy exhibits both low Young's modulus(61 GPa)and high yield strength(912 MPa).The experimental results prove that the proposed strategy is appropriate for developing titanium alloys with superior yield strength-to-modulus ratio than those of conventional metallic biomedical materials.Present study might shed light on the research and development of advanced biomedical titanium alloys with low Young's modulus and high yield strength.展开更多
Under submerged conditions, compared with traditional self-excited oscillating pulsed waterjets(SOPWs), annular fluid-enhanced self-excited oscillating pulsed waterjets(AFESOPWs) exhibit a higher surge pressure throug...Under submerged conditions, compared with traditional self-excited oscillating pulsed waterjets(SOPWs), annular fluid-enhanced self-excited oscillating pulsed waterjets(AFESOPWs) exhibit a higher surge pressure through self-priming. However, their pressure frequency and cavitation characteristics remain unclear, resulting in an inability to fully utilize resonance and cavitation erosion to break coal and rock. In this study, high-frequency pressure testing, high-speed photography, and large eddy simulation(LES) are used to investigate the distribution of the pressure frequency band, evolution law of the cavitation cloud, and its regulation mechanism of a continuous waterjet, SOPW, and AFESOPW. The results indicated that the excitation of the plunger pump, shearing layer vortex, and bubble collapse corresponded to the three high-amplitude frequency bands of the waterjet pressure. AFESOPWs have an additional self-priming frequency that can produce a larger amplitude under a synergistic effect with the second high-amplitude frequency band. A better cavitation effect was produced after self-priming the annulus fluid, and the shedding frequency of the cavitation clouds of the three types of waterjets was linearly related to the cavitation number. The peak pressure of the waterjet and cavitation erosion effect can be improved by modulating the waterjet pressure oscillation frequency and cavitation shedding frequency.展开更多
All-season thermal management with zero energy consumption and emissions is more crucial to global decarbonization over traditional energy-intensive cooling/heating systems.However,the static single thermal management...All-season thermal management with zero energy consumption and emissions is more crucial to global decarbonization over traditional energy-intensive cooling/heating systems.However,the static single thermal management for cooling or heating fails to self-regulate the temperature in dynamic seasonal temperature condition.Herein,inspired by the dual-temperature regulation function of the fur color changes on the backs and abdomens of penguins,a smart thermal management composite hydrogel(PNA@H-PM Gel)system was subtly created though an"on-demand"dual-layer structure design strategy.The PNA@H-PM Gel system features synchronous solar and thermal radiation modulation as well as tunable phase transition temperatures to meet the variable seasonal thermal requirements and energy-saving demands via self-adaptive radiative cooling and solar heating regulation.Furthermore,this system demonstrates superb modulations of both the solar reflectance(ΔR=0.74)and thermal emissivity(ΔE=0.52)in response to ambient temperature changes,highlighting efficient temperature regulation with average radiative cooling and solar heating effects of 9.6℃in summer and 6.1℃in winter,respectively.Moreover,compared to standard building baselines,the PNA@H-PM Gel presents a more substantial energy-saving cooling/heating potentials for energy-efficient buildings across various regions and climates.This novel solution,inspired by penguins in the real world,will offer a fresh approach for producing intelligent,energy-saving thermal management materials,and serve for temperature regulation under dynamic climate conditions and even throughout all seasons.展开更多
The traditional von Neumann architecture faces inherent limitations due to the separation of memory and computa-tion,leading to high energy consumption,significant latency,and reduced operational efficiency.Neuromorph...The traditional von Neumann architecture faces inherent limitations due to the separation of memory and computa-tion,leading to high energy consumption,significant latency,and reduced operational efficiency.Neuromorphic computing,inspired by the architecture of the human brain,offers a promising alternative by integrating memory and computational func-tions,enabling parallel,high-speed,and energy-efficient information processing.Among various neuromorphic technologies,ion-modulated optoelectronic devices have garnered attention due to their excellent ionic tunability and the availability of multi-dimensional control strategies.This review provides a comprehensive overview of recent progress in ion-modulation optoelec-tronic neuromorphic devices.It elucidates the key mechanisms underlying ionic modulation of light fields,including ion migra-tion dynamics and capture and release of charge through ions.Furthermore,the synthesis of active materials and the proper-ties of these devices are analyzed in detail.The review also highlights the application of ion-modulation optoelectronic devices in artificial vision systems,neuromorphic computing,and other bionic fields.Finally,the existing challenges and future direc-tions for the development of optoelectronic neuromorphic devices are discussed,providing critical insights for advancing this promising field.展开更多
High temperature piezoelectric energy harvester(HTPEH)is an important solution to replace chemical battery to achieve independent power supply of HT wireless sensors.However,simultaneously excellent performances,inclu...High temperature piezoelectric energy harvester(HTPEH)is an important solution to replace chemical battery to achieve independent power supply of HT wireless sensors.However,simultaneously excellent performances,including high figure of merit(FOM),insulation resistivity(ρ)and depolarization temperature(Td)are indispensable but hard to achieve in lead-free piezoceramics,especially operating at 250°C has not been reported before.Herein,well-balanced performances are achieved in BiFeO3–BaTiO3 ceramics via innovative defect engineering with respect to delicate manganese doping.Due to the synergistic effect of enhancing electrostrictive coefficient by polarization configuration optimization,regulating iron ion oxidation state by high valence manganese ion and stabilizing domain orientation by defect dipole,comprehensive excellent electrical performances(Td=340°C,ρ250°C>10^(7)Ωcm and FOM_(250°C)=4905×10^(–15)m^(2)N^(−1))are realized at the solid solubility limit of manganese ions.The HT-PEHs assembled using the rationally designed piezoceramic can allow for fast charging of commercial electrolytic capacitor at 250°C with high energy conversion efficiency(η=11.43%).These characteristics demonstrate that defect engineering tailored BF-BT can satisfy high-end HT-PEHs requirements,paving a new way in developing selfpowered wireless sensors working in HT environments.展开更多
El Niño-Southern Oscillation(ENSO)is a major driver of climate change in middle and low latitudes and thus strongly influences the terrestrial carbon cycle through land-air interaction.Both the ENSO modulation an...El Niño-Southern Oscillation(ENSO)is a major driver of climate change in middle and low latitudes and thus strongly influences the terrestrial carbon cycle through land-air interaction.Both the ENSO modulation and carbon flux variability are projected to increase in the future,but their connection still needs further investigation.To investigate the impact of future ENSO modulation on carbon flux variability,this study used 10 CMIP6 earth system models to analyze ENSO modulation and carbon flux variability in middle and low latitudes,and their relationship,under different scenarios simulated by CMIP6 models.The results show a high consistency in the simulations,with both ENSO modulation and carbon flux variability showing an increasing trend in the future.The higher the emissions scenario,especially SSP5-8.5 compared to SSP2-4.5,the greater the increase in variability.Carbon flux variability in the middle and low latitudes under SSP2-4.5 increases by 30.9%compared to historical levels during 1951-2000,while under SSP5-8.5 it increases by 58.2%.Further analysis suggests that ENSO influences mid-and low-latitude carbon flux variability primarily through temperature.This occurrence may potentially be attributed to the increased responsiveness of gross primary productivity towards regional temperature fluctuations,combined with the intensified influence of ENSO on land surface temperatures.展开更多
Oxygen evolution reaction(OER)is often regarded as a crucial bottleneck in the field of renewable energy storage and conversion.To further accelerate the sluggish kinetics of OER,a cation and anion modulation strategy...Oxygen evolution reaction(OER)is often regarded as a crucial bottleneck in the field of renewable energy storage and conversion.To further accelerate the sluggish kinetics of OER,a cation and anion modulation strategy is reported here,which has been proven to be effective in preparing highly active electrocatalyst.For example,the cobalt,sulfur,and phosphorus modulated nickel hydroxide(denoted as NiCoPSOH)only needs an overpotential of 232 mV to reach a current density of 20 mA cm^(–2),demonstrating excellent OER performances.The cation and anion modulation facilitates the generation of high-valent Ni species,which would activate the lattice oxygen and switch the OER reaction pathway from conventional adsorbate evolution mechanism to lattice oxygen mechanism(LOM),as evidenced by the results of electrochemical measurements,Raman spectroscopy and differential electrochemical mass spectrometry.The LOM pathway of NiCoPSOH is further verified by the theoretical calculations,including the upshift of O 2p band center,the weakened Ni–O bond and the lowest energy barrier of rate-limiting step.Thus,the anion and cation modulated catalyst NiCoPSOH could effectively accelerate the sluggish OER kinetics.Our work provides a new insight into the cation and anion modulation,and broadens the possibility for the rational design of highly active electrocatalysts.展开更多
Two-terminal(2-T)perovskite(PVK)/CuIn(Ga)Se_(2)(CIGS)tandem solar cells(TSCs)have been considered as an ideal tandem cell because of their best bandgap matching regarding to Shockley–Queisser(S–Q)limits.However,the ...Two-terminal(2-T)perovskite(PVK)/CuIn(Ga)Se_(2)(CIGS)tandem solar cells(TSCs)have been considered as an ideal tandem cell because of their best bandgap matching regarding to Shockley–Queisser(S–Q)limits.However,the nature of the irregular rough morphology of commercial CIGS prevents people from improving tandem device performances.In this paper,D-homoserine lactone hydrochloride is proven to improve coverage of PVK materials on irregular rough CIGS surfaces and also passivate bulk defects by modulating the growth of PVK crystals.In addition,the minority carriers near the PVK/C60 interface and the incompletely passivated trap states caused interface recombination.A surface reconstruction with 2-thiopheneethylammonium iodide and N,N-dimethylformamide assisted passivates the defect sites located at the surface and grain boundaries.Meanwhile,LiF is used to create this field effect,repelling hole carriers away from the PVK and C60 interface and thus reducing recombination.As a result,a 2-T PVK/CIGS tandem yielded a power conversion efficiency of 24.6%(0.16 cm^(2)),one of the highest results for 2-T PVK/CIGS TSCs to our knowledge.This validation underscores the potential of our methodology in achieving superior performance in PVK/CIGS tandem solar cells.展开更多
Continuous annealing simulation is used in studying the influence of continuous annealing process parameters on the microstructure and mechanical properties of a GPa-grade C-Si-Mn-Cr-Mo dual-phase steel.The experiment...Continuous annealing simulation is used in studying the influence of continuous annealing process parameters on the microstructure and mechanical properties of a GPa-grade C-Si-Mn-Cr-Mo dual-phase steel.The experimental results indicate that increasing soaking time increases the volume fraction of martensite and the size of martensite islands, as well as tensile strength(TS) and yield strength(YS),while decreasing plasticity.As the steel slowly cools to a lower temperature prior to final quenching, TS and YS decrease, whereas elongation increases.The decrease in martensite content is due to the partial decomposition of austenite into ferrite during long slow cooling before quenching.As overaging temperature increases because of the tempering of martensite and aging of ferrite, TS decreases and YS increases.Work hardening analysis shows that in the initial stage of deformation, low overaging temperatures enhance work hardening ability.展开更多
Introduction:Accurate preoperative localization of parathyroid glands(PGs)is crucial for patients with secondary hyperparathyroidism scheduled for parathyroidectomy.However,despite its importance,localization remains ...Introduction:Accurate preoperative localization of parathyroid glands(PGs)is crucial for patients with secondary hyperparathyroidism scheduled for parathyroidectomy.However,despite its importance,localization remains challenging since current preoperative imaging modalities for PG localization vary in sensitivity and accessibility.Materials and methods:In this study,we developed a deep learning model for PG identification using a dual-phase computed tomography(CT)dataset,including unenhanced CT and contrast-enhanced(CE)CT data,and validated the model’s sensitivity in clinical application.A retrospective study was conducted using 94 CT images obtained from 47 patients(one plain CT image and one CE CT image per patient).The data were randomly assigned to a training set(38 cases,76 CT images)and a test set(9 cases,18 CT images)based on per-patient splits.A three-dimensional U-Net model was trained using the training set and then validated using the test set.An analysis was conducted to compare the model’s and clinicians’sensitivity in detecting PGs based on various imaging modalities.An error analysis and an intermodal imaging complementarity analysis were performed to provide references for subsequent model enhancement and application.Results:The dual-phase CT model identified PGs with a diagnostic sensitivity of 94.44%.This was significantly higher than the sensitivity achieved by clinicians using ultrasonography(61.11%,P=0.0013)and CT(72.22%,P=0.0238).Additionally,the sensitivity achieved using the dual-phase CT model was comparable to that achieved using technetium-99m-methoxyisobutylisonitrile single-photon emission CT/CT(86.11%,P=0.429).We also found that combining predictions from this model with other imaging modalities further improved the PG detection rates.Conclusions:The study findings suggest that using a deep learning model with plain and CE CT data could improve PG identification prior to thyroidectomy or parathyroidectomy.展开更多
The subnucleus reticularis dorsalis(SRD),also known as the dorsal reticular nucleus(DRt)or dorsal medullary reticular nucleus(MdD),which resides at the caudal end of the medulla,plays a pivotal role in regulating pain...The subnucleus reticularis dorsalis(SRD),also known as the dorsal reticular nucleus(DRt)or dorsal medullary reticular nucleus(MdD),which resides at the caudal end of the medulla,plays a pivotal role in regulating pain perception.Despite extensive research efforts to unravel its mechanisms,the operational intricacies of SRD remain poorly understood.Advances in experimental methodologies such as brain imaging and chemogenetics have facilitated deeper investigations into the involvement of SRD in various pain disorders.This comprehensive review aims to analyze 36 years(1989–2024)of preclinical research highlighting the critical role of SRD in diffuse noxious inhibitory control(DNIC),also known as conditioned pain modulation(CPM)in humans,and its interconnected neural circuits.Moreover,this review explores the neural circuits related to SRD,including locus coeruleus(LC)-SRD,parabrachial nucleus(PBN)-SRD,rostroventromedial medulla(RVM)-ventrolateral medulla(VLM)-SRD,anterior cingulate cortex(ACC)-SRD,medial medullary reticular formation(mMRF)-SRD,and dorsal striatum(DS)-SRD.Their activation also plays a significant role in analgesia.The pivotal roles of neurotransmitters such asμ-opioid receptor(MOR),noradrenaline,and metabotropic glutamate receptor 7(mGluR7)in modulating SRD responsiveness to pain stimuli are also discussed,as are the influences of SRD on different pain types.This review identified promising avenues for innovative analgesic treatments by shedding light on potential therapeutic strategies targeting SRD.展开更多
Face-centered cubic(FCC)equi-atomic multi-principal element alloys(MPEAs)exhibit excellent mechan-ical properties over a broad temperature range from cryogenic temperatures(CTs)to room temperature(RT).Specifically,whi...Face-centered cubic(FCC)equi-atomic multi-principal element alloys(MPEAs)exhibit excellent mechan-ical properties over a broad temperature range from cryogenic temperatures(CTs)to room temperature(RT).Specifically,while the deformation mechanism is dominated solely by dislocation slip at RT,the re-duction in stacking fault energy(SFE)at CTs leads to enhanced strain hardening with deformation twin-ning.This study employs in-situ neutron diffraction to reveal the temperature-dependent deformation be-havior of the FCC/body-centered cubic(BCC)dual-phase(DP)Al7(CoNiV)93 medium-entropy alloy(MEA),which possesses a matrix exhibiting deformation behavior analogous to that of representative equi-atomic MPEAs.Alongside the increased lattice friction stress associated with reduced temperature as a thermal component,deformation twinning at liquid nitrogen temperature(LNT)facilitates dislocation activity in the FCC matrix,leading to additional strain hardening induced by the dynamic Hall-Petch effect.This would give the appearance that the improved strengthening/hardening behaviors at LNT,compared to RT,are primarily attributable to the FCC phase.In contrast,the BCC precipitates are governed solely by dislocation slip for plastic deformation at both 77 K and 298 K,exhibiting a similar trend in dislocation density evolution.Nevertheless,empirical and quantitative findings indicate that the intrinsically high Peierls-Nabarro barriers in the BCC precipitates exhibit pronounced temperature-dependent lattice fric-tion stress,suggesting that the BCC precipitates play a more significant role in the temperature-dependent strengthening/hardening behaviors for the DP-MEA.This study provides a comprehensive understanding of deformation behavior by thoroughly analyzing temperature-dependent strengthening/hardening mech-anisms across various DP-MPEA systems,offering valuable guidelines for future alloy design.展开更多
基金National Natural Science Foundation of China(12405168)The Fundamental Research Funds for the Central Universities,China(2024CDJXY004)。
文摘[Background]High harmonic cavities are widely used in electron storage rings to lengthen thebunch,lower the bunch peak current,thereby reducing the IBS effect,enhancing the Touschek lifetime,as well asproviding Landau damping,which is particularly important for storage rings operating with ultra-low emittance or atlow beam energy.[Purpose]To further increase the bunch length without additional hardware costs,the phasemodulation in a dual-RF system is considered.[Methods]In this paper,turn-by-turn simulations incorporating randomsynchrotron radiation excitation are conducted,and a brief analysis is presented to explain the bunch lengtheningmechanism.[Results]Simulation results reveal that the peak current can be further reduced,thereby mitigating IBSeffects and enhancing the Touschek lifetime.Although the energy spread increases,which tends to reduce thebrightness of higher-harmonic radiation from the undulator,the brightness of the fundamental harmonic can,in fact,beimproved.
基金supported by the National Science and Technology Major Project-Intelligent Manufacturing Systems And Robots(2025ZD1602200)the National Key Research and Development Program of China(Grant No.2022YFB3304800).
文摘The accurate establishment of a ferrite transformation start temperature model is crucial to design a reasonable controlled rolling process and ensure uniform microstructure in aluminum bearing dual-phase steel.The measurements of the expansion-temperature curves of aluminum bearing dual-phase steel under continuous cooling and isothermal conditions are presented,utilizing a dynamic transformation dilatometer experiment.Based on these expansion-temperature curves,the start temperature and incubation time of ferrite transformation were determined,elucidating the influence of process parameters on both the incubation time and the start temperature of ferrite transformation.By integrating metallurgical principles with measured incubation time of ferrite transformation,and considering the effects of temperature and strain,a fitting model for the variation in volume free energy during ferrite nucleation was derived.Building upon this foundation,a high-precision incubation time of ferrite transformation mathematical model for the experimental steel was established.To more accurately calculate the start temperature of ferrite transformation under continuous cooling conditions,the Scheil’s additivity rule was modified to account for the effects of deformation and cooling rate.The results indicate that the modification coefficient decreases with increasing the cooling rate and strain,thereby significantly improving the accuracy of calculating the starting temperature of ferrite transformation using the modified additivity rule.
基金funding from the National Key Research and Development Program of China(No.2018YFE0110000)the National Natural Science Foundation of China(No.11274259,No.11574258)the Science and Technology Commission Foundation of Shanghai(21DZ1205500)in support of the present research.
文摘While reinforcement learning-based underwater acoustic adaptive modulation shows promise for enabling environment-adaptive communication as supported by extensive simulation-based research,its practical performance remains underexplored in field investigations.To evaluate the practical applicability of this emerging technique in adverse shallow sea channels,a field experiment was conducted using three communication modes:orthogonal frequency division multiplexing(OFDM),M-ary frequency-shift keying(MFSK),and direct sequence spread spectrum(DSSS)for reinforcement learning-driven adaptive modulation.Specifically,a Q-learning method is used to select the optimal modulation mode according to the channel quality quantified by signal-to-noise ratio,multipath spread length,and Doppler frequency offset.Experimental results demonstrate that the reinforcement learning-based adaptive modulation scheme outperformed fixed threshold detection in terms of total throughput and average bit error rate,surpassing conventional adaptive modulation strategies.
基金supported by the National Natural Science Foundation of China(Grant Nos.52125405 and U22A20108)Thailand Science Research and Innovation Fund Chulalongkorn University,National Research Council of Thailand(NRCT)and Chulalongkorn University(N42A660383).D.D.Zhang would like to thank the financial support from the Scientific Research Fund of Liaoning Provincial Education Department of China(No.JYTQN2023289)+3 种基金Liaoning Provincial Science and Technology Joint Plan(Fund)Project(No.2023-BSBA-259)and the opening project of State Key Laboratory of Metastable Materials Science and Technology,Yanshan University(No.202404).J.Cao would like to acknowledge the support from National Natural Science Foundation of China(Grant No.52402279)China Postdoctoral Science Foundation Special Funding(Grant Nos.2025T180002,2024M751753)the opening project of State Key Laboratory of Metastable Materials Science and Technology(Yanshan University)(No.202401).
文摘Aqueous zinc-ion batteries(AZIBs)offer promising safety and affordability,but suffer from dendritic Zn growth and parasitic side reactions at the electrode-electrolyte interface.Herein,we construct a dual-region interfacial modulation framework by molecularly reconfiguring the Helmholtz double layer via trace methyl methacrylate(MMA).Exploiting its amphiphilic and functionally asymmetric architecture,MMA enables a coordinated interfacial reconstruction that disrupts Zn^(2+)solvation in the outer Helmholtz plane,builds a chemisorbed coordination layer in the inner plane,and modulates local interfacial chemistry with spatial precision.This dualregion regulation collectively suppresses water reactivity,facilitates Zn^(2+)desolvation,and drives crystallo-graphically preferred deposition along the(101)plane,promoting lateral growth and mitigating dendrite for-mation.As a result,symmetric Zn||Zn cells exhibit over 4200 h of stable cycling at 1 mA cm^(-2) and maintain 1100 h of operation at 2 mA cm^(-2),even at 0℃.Zn||Ti half-cells achieve a Coulombic efficiency of 99.83%,while Zn||NH_(4)V_(4)O_(10) full cells deliver 93.92%capacity retention after 400 cycles at 2 A g^(-1),and preserve 85.3%after 300 cycles at 0℃.This work demonstrates a scalable,mechanism-driven electrolyte design paradigm for dendrite-free and high-performance aqueous Zn metal batteries.
基金provided by the National Natural Sciences Foundation of China (82270979)High-Level Hospital Construction Project (0224C001,0224C050)Cultivation Program for Reserve Talents for Academic Leaders (2023A208) of Nanjing Stomatological Hospital,Affiliated Hospital of Medical School,Institute of Stomatology,Nanjing University。
文摘Epidemiological studies have highlighted an association between periodontitis and osteoporosis.However,the mechanism underlining this association remains unclear.Here,we revealed significant differences in the salivary microbiota between periodontally healthy individuals and periodontitis patients,with periodontitis patients exhibiting increased salivary microbiota diversity and an elevated abundance of pathogenic bacteria.Using an ovariectomized(OVX) mouse model,we demonstrated that the salivary microbiota from periodontitis patients exacerbated bone destruction by modulating the gut microbiota.Metabolomic analysis revealed that the periodontitis-associated salivary microbiota suppressed tryptophan metabolism.The tryptophan metabolite indole-3-lactic acid(ILA) directly inhibited osteoclast formation and differentiation.In OVX mice treated with periodontitis salivary microbiota,supplementation with ILA effectively suppressed osteoclastogenesis and alleviated the detrimental effects of periodontitis-associated salivary microbiota on systemic bones.In summary,our data demonstrate that periodontitis can affect systemic bone metabolism via the oral-gut axis and that ILA supplementation serves as a potential therapeutic option to mitigate these adverse effects.
基金supported by the National Natural Science Foundation of China,No.82204663(to TZ)the Natural Science Foundation of Shandong Province,No.ZR2022QH058(to TZ).
文摘Modulations of mitochondrial dysfunction,which involve a series of dynamic processes such as mitochondrial biogenesis,mitochondrial fusion and fission,mitochondrial transport,mitochondrial autophagy,mitochondrial apoptosis,and oxidative stress,play an important role in the onset and progression of stroke.With a better understanding of the critical role of mitochondrial dysfunction modulations in post-stroke neurological injury,these modulations have emerged as a potential target for stroke prevention and treatment.Additionally,since effective treatments for stroke are extremely limited and natural products currently offer some outstanding advantages,we focused on the findings and mechanisms of action related to the use of natural products for targeting mitochondrial dysfunction in the treatment of stroke.Natural products achieve neuroprotective through multi-target regulation of mitochondrial dysfunction encompassing the following processes:(1)Mitochondrial biogenesis:Cordyceps and hydroxysafflor yellow A activate the peroxisome proliferator-activated receptor gamma coactivator 1-alpha/nuclear respiratory factor pathway,promote mitochondrial DNA replication and respiratory chain protein synthesis,and thereby restore energy supply in the ischemic penumbra.(2)Mitochondrial dynamics balance:Ginsenoside Rb3 promotes Opa1-mediated neural stem cell migration and diffusion for recovery of damaged brain tissue.(3)Mitochondrial autophagy:Gypenoside XVII selectively eliminates damaged mitochondria via the phosphatase and tensin homolog-induced kinase 1/Parkin pathway and blocks reactive oxygen species and the NOD-like receptor protein 3 inflammasome cascade,thereby alleviating blood-brain barrier damage.(4)Anti-apoptotic mechanisms:Ginkgolide K inhibits Bax mitochondrial translocation and downregulates caspase-3/9 activity,reducing neuronal programmed death induced by ischemia-reperfusion.(5)Oxidative stress regulation:Scutellarin exerts antioxidant properties and improves neurological function by modulating the extracellular signal-regulated kinase 5-Kruppel-like factor 2-endothelial nitric oxide synthase signaling pathway.(6)Intercellular mitochondrial transport:Neuroprotective effects of Chrysophanol are associated with accelerated mitochondrial transfer from astrocytes to neurons.Existing studies have confirmed that natural products exhibit neuroprotective effects through multidimensional interventions targeting mitochondrial dysfunction in both ischemic and hemorrhagic stroke models.However,their clinical translation still faces challenges,such as the difficulty in standardization due to component complexity,insufficient cross-regional clinical data,and the lack of long-term safety evaluations.Future research should aim to integrate new technologies,such as single-cell sequencing and organoid models,to deeply explore the mitochondria-targeting mechanisms of natural products and validate their efficacy through multicenter clinical trials,providing theoretical support and translational pathways for the development of novel anti-stroke drugs.
基金supports from National Key Research and Development Program of China(2021YFB2800703)Sichuan Province Science and Technology Support Program(25QNJJ2419)+1 种基金National Natural Science Foundation of China(U22A2008,12404484)Laoshan Laboratory Science and Technology Innovation Project(LSKJ202200801).
文摘Diatomic metasurfaces designed for interferometric mechanisms possess significant potential for the multidimensional manipulation of electromagnetic waves,including control over amplitude,phase,frequency,and polarization.Geometric phase profiles with spin-selective properties are commonly associated with wavefront modulation,allowing the implementation of conjugate strategies within orthogonal circularly polarized channels.Simultaneous control of these characteristics in a single-layered diatomic metasurface will be an apparent technological extension.Here,spin-selective modulation of terahertz(THz)beams is realized by assembling a pair of meta-atoms with birefringent effects.The distinct modulation functions arise from geometric phase profiles characterized by multiple rotational properties,which introduce independent parametric factors that elucidate their physical significance.By arranging the key parameters,the proposed design strategy can be employed to realize independent amplitude and phase manipulation.A series of THz metasurface samples with specific modulation functions are characterized,experimentally demonstrating the accuracy of on-demand manipulation.This research paves the way for all-silicon meta-optics that may have great potential in imaging,sensing and detection.
基金supported by the National Natural Science Foundation of China(No.52101128)the Jiangsu Provincial Key Research and Development Program(No.BE023059)+1 种基金the Post-doctoral Science Foundation of China(No.2022M710021)the Northeastern University Postdoctoral Research Fund of China(No.20220202).
文摘Fracture strain becomes critical for the local formability and crash performance of carbody components when the tensile strength exceeds 1000 MPa.Regrettably,high-strength quenching and partitioning(Q&P)steels and dual-phase(DP)steels always focus on improving the tensile ductility for stretch formability,while ignoring their limited fracture strain.In this work,we explored a novel strategy,i.e.,developing a high fracture strain ferrite-martensite dual-phase steel(HFS-DP)maintaining good strength–ductility balance by suppressing intense strain localization during deformation and enhancing martensite deformability via microstructure design including grain refinement,nano-precipitate hardening in soft ferrite phase,low-carbon and high fraction martensite.HFS-DP demonstrates a remarkable 26%and 47%improvement in tensile ductility and fracture strain,respectively,compared to commercial DP1180 steel with similar ultimate tensile strength.Furthermore,HFS-DP also exhibits a substantial 39%improvement in fracture strain compared to retained austenite-involved commercial QP1180 steel.The detailed processes of strain partitioning,strain localization,and damage formation during deformation were revealed through in-situ scanning electron microscopy(SEM)observation combined with digital image correlation(DIC).The results indicate that the excellent coordinated deformation between ferrite and martensite,coupled with microstructure refinement,effectively suppresses intense strain localization.Moreover,the excellent martensite deformability resulting from the low carbon content also aids in retarding crack formation.This combination effectively suppresses damage initiation and development during deformation,therefore the fracture strain is significantly improved.This study not only contributes to a deeper understanding of the strain localization and damage process during tensile deformation of DP steels,but also provides a new perspective on designing ultrahigh strength steels with high ductility and fracture strain.
基金the National Natural Science Foundation of China(Nos.51671012,51831006 and 51971009)the International Science and Technology Cooperation Program of China(No.2015DFA51430)the Fundamental Research Funds for the Central Universities。
文摘In this study,a novel strategy for developingα+βdual-phase titanium alloys with low Young's modulus and high yield strength was proposed,and a Ti-15Nb-5Zr-4Sn-1 Fe alloy was developed through theoretical composition design and microstructure manipulation.After hot-rolling and subsequent annealing,a high volume fraction of ultrafine grainedαphase embedded in metastableβ-matrix was formed in the microstructure as intended.Consequently,this alloy exhibits both low Young's modulus(61 GPa)and high yield strength(912 MPa).The experimental results prove that the proposed strategy is appropriate for developing titanium alloys with superior yield strength-to-modulus ratio than those of conventional metallic biomedical materials.Present study might shed light on the research and development of advanced biomedical titanium alloys with low Young's modulus and high yield strength.
基金supported by the program for National Natural Science Foundation of China (Nos. 52174173, 52274188, and 52104190)the Joint Funds of the National Natural Science Foundation of China (No. U24A2091)+1 种基金The Natural Science Foundation of Henan Polytechnic University (No. B2021-2)Double FirstClass Initiative of Safety and Energy Engineering (Henan Polytechnic University) (Nos. AQ20240703 and AQ20230304)。
文摘Under submerged conditions, compared with traditional self-excited oscillating pulsed waterjets(SOPWs), annular fluid-enhanced self-excited oscillating pulsed waterjets(AFESOPWs) exhibit a higher surge pressure through self-priming. However, their pressure frequency and cavitation characteristics remain unclear, resulting in an inability to fully utilize resonance and cavitation erosion to break coal and rock. In this study, high-frequency pressure testing, high-speed photography, and large eddy simulation(LES) are used to investigate the distribution of the pressure frequency band, evolution law of the cavitation cloud, and its regulation mechanism of a continuous waterjet, SOPW, and AFESOPW. The results indicated that the excitation of the plunger pump, shearing layer vortex, and bubble collapse corresponded to the three high-amplitude frequency bands of the waterjet pressure. AFESOPWs have an additional self-priming frequency that can produce a larger amplitude under a synergistic effect with the second high-amplitude frequency band. A better cavitation effect was produced after self-priming the annulus fluid, and the shedding frequency of the cavitation clouds of the three types of waterjets was linearly related to the cavitation number. The peak pressure of the waterjet and cavitation erosion effect can be improved by modulating the waterjet pressure oscillation frequency and cavitation shedding frequency.
基金the funding and generous support of the National Natural Science Foundation of China(52103263,52271249)the Key Project of International Science&Technology Cooperation of Shaanxi Province(2023-GHZD-09)+5 种基金the Key Project of Science Foundation of Education Department of Shaanxi Province(22JY011)the Key Project of Scientific Research and Development of Shaanxi Province(2023GXLH-070)the Qinchuangyuan"Scientist+Engineer"Team of Shaanxi Province(2023KXJ-069)the Key Research and Development Program of Shaanxi(2023-YBGY-488)the Sci-tech Innovation Team of Shaanxi Province(2024RS-CXTD-46)the Key Research and Development Program of Shaanxi Province(2020ZDLGY13-11).
文摘All-season thermal management with zero energy consumption and emissions is more crucial to global decarbonization over traditional energy-intensive cooling/heating systems.However,the static single thermal management for cooling or heating fails to self-regulate the temperature in dynamic seasonal temperature condition.Herein,inspired by the dual-temperature regulation function of the fur color changes on the backs and abdomens of penguins,a smart thermal management composite hydrogel(PNA@H-PM Gel)system was subtly created though an"on-demand"dual-layer structure design strategy.The PNA@H-PM Gel system features synchronous solar and thermal radiation modulation as well as tunable phase transition temperatures to meet the variable seasonal thermal requirements and energy-saving demands via self-adaptive radiative cooling and solar heating regulation.Furthermore,this system demonstrates superb modulations of both the solar reflectance(ΔR=0.74)and thermal emissivity(ΔE=0.52)in response to ambient temperature changes,highlighting efficient temperature regulation with average radiative cooling and solar heating effects of 9.6℃in summer and 6.1℃in winter,respectively.Moreover,compared to standard building baselines,the PNA@H-PM Gel presents a more substantial energy-saving cooling/heating potentials for energy-efficient buildings across various regions and climates.This novel solution,inspired by penguins in the real world,will offer a fresh approach for producing intelligent,energy-saving thermal management materials,and serve for temperature regulation under dynamic climate conditions and even throughout all seasons.
基金supported by National Natural Science Foundation of China(62174164,U23A20568,and U22A2075)National Key Research and Development Project(2021YFA1202600)+2 种基金Talent Plan of Shanghai Branch,Chinese Academy of Sciences(CASSHB-QNPD-2023-022)Ningbo Technology Project(2022A-007-C)Ningbo Key Research and Development Project(2023Z021).
文摘The traditional von Neumann architecture faces inherent limitations due to the separation of memory and computa-tion,leading to high energy consumption,significant latency,and reduced operational efficiency.Neuromorphic computing,inspired by the architecture of the human brain,offers a promising alternative by integrating memory and computational func-tions,enabling parallel,high-speed,and energy-efficient information processing.Among various neuromorphic technologies,ion-modulated optoelectronic devices have garnered attention due to their excellent ionic tunability and the availability of multi-dimensional control strategies.This review provides a comprehensive overview of recent progress in ion-modulation optoelec-tronic neuromorphic devices.It elucidates the key mechanisms underlying ionic modulation of light fields,including ion migra-tion dynamics and capture and release of charge through ions.Furthermore,the synthesis of active materials and the proper-ties of these devices are analyzed in detail.The review also highlights the application of ion-modulation optoelectronic devices in artificial vision systems,neuromorphic computing,and other bionic fields.Finally,the existing challenges and future direc-tions for the development of optoelectronic neuromorphic devices are discussed,providing critical insights for advancing this promising field.
基金supported by the National Natural Science Foundation of China(Grant Nos.52272103 and 52072010)Beijing Natural Science Foundation(Grant Nos.2242029 and JL23004).
文摘High temperature piezoelectric energy harvester(HTPEH)is an important solution to replace chemical battery to achieve independent power supply of HT wireless sensors.However,simultaneously excellent performances,including high figure of merit(FOM),insulation resistivity(ρ)and depolarization temperature(Td)are indispensable but hard to achieve in lead-free piezoceramics,especially operating at 250°C has not been reported before.Herein,well-balanced performances are achieved in BiFeO3–BaTiO3 ceramics via innovative defect engineering with respect to delicate manganese doping.Due to the synergistic effect of enhancing electrostrictive coefficient by polarization configuration optimization,regulating iron ion oxidation state by high valence manganese ion and stabilizing domain orientation by defect dipole,comprehensive excellent electrical performances(Td=340°C,ρ250°C>10^(7)Ωcm and FOM_(250°C)=4905×10^(–15)m^(2)N^(−1))are realized at the solid solubility limit of manganese ions.The HT-PEHs assembled using the rationally designed piezoceramic can allow for fast charging of commercial electrolytic capacitor at 250°C with high energy conversion efficiency(η=11.43%).These characteristics demonstrate that defect engineering tailored BF-BT can satisfy high-end HT-PEHs requirements,paving a new way in developing selfpowered wireless sensors working in HT environments.
基金jointly supported by projects of the National Natural Science Foundation of China [grant numbers 42141017 and 41975112]。
文摘El Niño-Southern Oscillation(ENSO)is a major driver of climate change in middle and low latitudes and thus strongly influences the terrestrial carbon cycle through land-air interaction.Both the ENSO modulation and carbon flux variability are projected to increase in the future,but their connection still needs further investigation.To investigate the impact of future ENSO modulation on carbon flux variability,this study used 10 CMIP6 earth system models to analyze ENSO modulation and carbon flux variability in middle and low latitudes,and their relationship,under different scenarios simulated by CMIP6 models.The results show a high consistency in the simulations,with both ENSO modulation and carbon flux variability showing an increasing trend in the future.The higher the emissions scenario,especially SSP5-8.5 compared to SSP2-4.5,the greater the increase in variability.Carbon flux variability in the middle and low latitudes under SSP2-4.5 increases by 30.9%compared to historical levels during 1951-2000,while under SSP5-8.5 it increases by 58.2%.Further analysis suggests that ENSO influences mid-and low-latitude carbon flux variability primarily through temperature.This occurrence may potentially be attributed to the increased responsiveness of gross primary productivity towards regional temperature fluctuations,combined with the intensified influence of ENSO on land surface temperatures.
文摘Oxygen evolution reaction(OER)is often regarded as a crucial bottleneck in the field of renewable energy storage and conversion.To further accelerate the sluggish kinetics of OER,a cation and anion modulation strategy is reported here,which has been proven to be effective in preparing highly active electrocatalyst.For example,the cobalt,sulfur,and phosphorus modulated nickel hydroxide(denoted as NiCoPSOH)only needs an overpotential of 232 mV to reach a current density of 20 mA cm^(–2),demonstrating excellent OER performances.The cation and anion modulation facilitates the generation of high-valent Ni species,which would activate the lattice oxygen and switch the OER reaction pathway from conventional adsorbate evolution mechanism to lattice oxygen mechanism(LOM),as evidenced by the results of electrochemical measurements,Raman spectroscopy and differential electrochemical mass spectrometry.The LOM pathway of NiCoPSOH is further verified by the theoretical calculations,including the upshift of O 2p band center,the weakened Ni–O bond and the lowest energy barrier of rate-limiting step.Thus,the anion and cation modulated catalyst NiCoPSOH could effectively accelerate the sluggish OER kinetics.Our work provides a new insight into the cation and anion modulation,and broadens the possibility for the rational design of highly active electrocatalysts.
基金supported by“National Natural Science Foundation of China(U21A20171,U20A20245)”“Hubei Provincial Natural Science Foundation of China(2023AFA010)”+1 种基金“Independent Innovation Projects of the Hubei Longzhong Laboratory(2022ZZ-09)”“Social Public Welfare and Basic Research Special Project of Zhongshan(2020B2015).”。
文摘Two-terminal(2-T)perovskite(PVK)/CuIn(Ga)Se_(2)(CIGS)tandem solar cells(TSCs)have been considered as an ideal tandem cell because of their best bandgap matching regarding to Shockley–Queisser(S–Q)limits.However,the nature of the irregular rough morphology of commercial CIGS prevents people from improving tandem device performances.In this paper,D-homoserine lactone hydrochloride is proven to improve coverage of PVK materials on irregular rough CIGS surfaces and also passivate bulk defects by modulating the growth of PVK crystals.In addition,the minority carriers near the PVK/C60 interface and the incompletely passivated trap states caused interface recombination.A surface reconstruction with 2-thiopheneethylammonium iodide and N,N-dimethylformamide assisted passivates the defect sites located at the surface and grain boundaries.Meanwhile,LiF is used to create this field effect,repelling hole carriers away from the PVK and C60 interface and thus reducing recombination.As a result,a 2-T PVK/CIGS tandem yielded a power conversion efficiency of 24.6%(0.16 cm^(2)),one of the highest results for 2-T PVK/CIGS TSCs to our knowledge.This validation underscores the potential of our methodology in achieving superior performance in PVK/CIGS tandem solar cells.
文摘Continuous annealing simulation is used in studying the influence of continuous annealing process parameters on the microstructure and mechanical properties of a GPa-grade C-Si-Mn-Cr-Mo dual-phase steel.The experimental results indicate that increasing soaking time increases the volume fraction of martensite and the size of martensite islands, as well as tensile strength(TS) and yield strength(YS),while decreasing plasticity.As the steel slowly cools to a lower temperature prior to final quenching, TS and YS decrease, whereas elongation increases.The decrease in martensite content is due to the partial decomposition of austenite into ferrite during long slow cooling before quenching.As overaging temperature increases because of the tempering of martensite and aging of ferrite, TS decreases and YS increases.Work hardening analysis shows that in the initial stage of deformation, low overaging temperatures enhance work hardening ability.
文摘Introduction:Accurate preoperative localization of parathyroid glands(PGs)is crucial for patients with secondary hyperparathyroidism scheduled for parathyroidectomy.However,despite its importance,localization remains challenging since current preoperative imaging modalities for PG localization vary in sensitivity and accessibility.Materials and methods:In this study,we developed a deep learning model for PG identification using a dual-phase computed tomography(CT)dataset,including unenhanced CT and contrast-enhanced(CE)CT data,and validated the model’s sensitivity in clinical application.A retrospective study was conducted using 94 CT images obtained from 47 patients(one plain CT image and one CE CT image per patient).The data were randomly assigned to a training set(38 cases,76 CT images)and a test set(9 cases,18 CT images)based on per-patient splits.A three-dimensional U-Net model was trained using the training set and then validated using the test set.An analysis was conducted to compare the model’s and clinicians’sensitivity in detecting PGs based on various imaging modalities.An error analysis and an intermodal imaging complementarity analysis were performed to provide references for subsequent model enhancement and application.Results:The dual-phase CT model identified PGs with a diagnostic sensitivity of 94.44%.This was significantly higher than the sensitivity achieved by clinicians using ultrasonography(61.11%,P=0.0013)and CT(72.22%,P=0.0238).Additionally,the sensitivity achieved using the dual-phase CT model was comparable to that achieved using technetium-99m-methoxyisobutylisonitrile single-photon emission CT/CT(86.11%,P=0.429).We also found that combining predictions from this model with other imaging modalities further improved the PG detection rates.Conclusions:The study findings suggest that using a deep learning model with plain and CE CT data could improve PG identification prior to thyroidectomy or parathyroidectomy.
基金funded by the Key Program of the National Natural Science Foundation of China(No.82130122).
文摘The subnucleus reticularis dorsalis(SRD),also known as the dorsal reticular nucleus(DRt)or dorsal medullary reticular nucleus(MdD),which resides at the caudal end of the medulla,plays a pivotal role in regulating pain perception.Despite extensive research efforts to unravel its mechanisms,the operational intricacies of SRD remain poorly understood.Advances in experimental methodologies such as brain imaging and chemogenetics have facilitated deeper investigations into the involvement of SRD in various pain disorders.This comprehensive review aims to analyze 36 years(1989–2024)of preclinical research highlighting the critical role of SRD in diffuse noxious inhibitory control(DNIC),also known as conditioned pain modulation(CPM)in humans,and its interconnected neural circuits.Moreover,this review explores the neural circuits related to SRD,including locus coeruleus(LC)-SRD,parabrachial nucleus(PBN)-SRD,rostroventromedial medulla(RVM)-ventrolateral medulla(VLM)-SRD,anterior cingulate cortex(ACC)-SRD,medial medullary reticular formation(mMRF)-SRD,and dorsal striatum(DS)-SRD.Their activation also plays a significant role in analgesia.The pivotal roles of neurotransmitters such asμ-opioid receptor(MOR),noradrenaline,and metabotropic glutamate receptor 7(mGluR7)in modulating SRD responsiveness to pain stimuli are also discussed,as are the influences of SRD on different pain types.This review identified promising avenues for innovative analgesic treatments by shedding light on potential therapeutic strategies targeting SRD.
基金supported by the National Research Foundation of Korea(NRF)grant funded by the Korean government(MSIP)(Nos.NRF-2021R1A2C3006662,NRF-2022R1A5A1030054,and RS-2023-00281246)supported by the Basic Science Research Program‘Fostering the Next Generation of Researchers(Ph.D.Candidate)’through the NRF funded by the Ministry of Edu-cation(No.RS-2023-00275651).
文摘Face-centered cubic(FCC)equi-atomic multi-principal element alloys(MPEAs)exhibit excellent mechan-ical properties over a broad temperature range from cryogenic temperatures(CTs)to room temperature(RT).Specifically,while the deformation mechanism is dominated solely by dislocation slip at RT,the re-duction in stacking fault energy(SFE)at CTs leads to enhanced strain hardening with deformation twin-ning.This study employs in-situ neutron diffraction to reveal the temperature-dependent deformation be-havior of the FCC/body-centered cubic(BCC)dual-phase(DP)Al7(CoNiV)93 medium-entropy alloy(MEA),which possesses a matrix exhibiting deformation behavior analogous to that of representative equi-atomic MPEAs.Alongside the increased lattice friction stress associated with reduced temperature as a thermal component,deformation twinning at liquid nitrogen temperature(LNT)facilitates dislocation activity in the FCC matrix,leading to additional strain hardening induced by the dynamic Hall-Petch effect.This would give the appearance that the improved strengthening/hardening behaviors at LNT,compared to RT,are primarily attributable to the FCC phase.In contrast,the BCC precipitates are governed solely by dislocation slip for plastic deformation at both 77 K and 298 K,exhibiting a similar trend in dislocation density evolution.Nevertheless,empirical and quantitative findings indicate that the intrinsically high Peierls-Nabarro barriers in the BCC precipitates exhibit pronounced temperature-dependent lattice fric-tion stress,suggesting that the BCC precipitates play a more significant role in the temperature-dependent strengthening/hardening behaviors for the DP-MEA.This study provides a comprehensive understanding of deformation behavior by thoroughly analyzing temperature-dependent strengthening/hardening mech-anisms across various DP-MPEA systems,offering valuable guidelines for future alloy design.