Hyperpolarization of nuclear spins is crucial for advancing nuclear magnetic resonance and quantum information technologies,as nuclear spins typically exhibit extremely low polarization at room temperature due to thei...Hyperpolarization of nuclear spins is crucial for advancing nuclear magnetic resonance and quantum information technologies,as nuclear spins typically exhibit extremely low polarization at room temperature due to their small gyromagnetic ratios.A promising approach to achieving high nuclear spin polarization is transferring the polarization of electrons to nuclear spins.The nitrogen-vacancy(NV)center in diamond has emerged as a highly effective medium for this purpose,and various hyperpolarization protocols have been developed.Among these,the pulsed polarization(PulsePol)method has been extensively studied due to its robustness against static energy shifts of the electron spin.In this work,we present a novel polarization protocol and uncover a family of magic sequences for hyperpolarizing nuclear spins,with PulsePol emerging as a special case of our general approach.Notably,we demonstrate that some of these magic sequences exhibit significantly greater robustness compared to the PulsePol protocol in the presence of finite half𝜋pulse duration of the protocol,Rabi and detuning errors.This enhanced robustness positions our protocol as a more suitable candidate for hyper-polarizing nuclear spins species with large gyromagnetic ratios and also ensures better compatibility with high-efficiency readout techniques at high magnetic fields.Additionally,the generality of our protocol allows for its direct application to other solid-state quantum systems beyond the NV center.展开更多
Strokes include both ischemic stroke,which is mediated by a blockade or reduction in the blood supply to the brain,and hemorrhagic stroke,which comprises intracerebral hemorrhage and subarachnoid hemorrhage and is cha...Strokes include both ischemic stroke,which is mediated by a blockade or reduction in the blood supply to the brain,and hemorrhagic stroke,which comprises intracerebral hemorrhage and subarachnoid hemorrhage and is characterized by bleeding within the brain.Stroke is a lifethreatening cerebrovascular condition characterized by intricate pathophysiological mechanisms,including oxidative stress,inflammation,mitochondrial dysfunction,and neuronal injury.Critical transcription factors,such as nuclear factor erythroid 2-related factor 2 and nuclear factor kappa B,play central roles in the progression of stroke.Nuclear factor erythroid 2-related factor 2 is sensitive to changes in the cellular redox status and is crucial in protecting cells against oxidative damage,inflammatory responses,and cytotoxic agents.It plays a significant role in post-stroke neuroprotection and repair by influencing mitochondrial function,endoplasmic reticulum stress,and lysosomal activity and regulating metabolic pathways and cytokine expression.Conversely,nuclear factor-kappa B is closely associated with mitochondrial dysfunction,the generation of reactive oxygen species,oxidative stress exacerbation,and inflammation.Nuclear factor-kappa B contributes to neuronal injury,apoptosis,and immune responses following stroke by modulating cell adhesion molecules and inflammatory mediators.The interplay between these pathways,potentially involving crosstalk among various organelles,significantly influences stroke pathophysiology.Advancements in single-cell sequencing and spatial transcriptomics have greatly improved our understanding of stroke pathogenesis and offer new opportunities for the development of targeted,individualized,cell typespecific treatments.In this review,we discuss the mechanisms underlying the involvement of nuclear factor erythroid 2-related factor 2 and nuclear factor-kappa B in both ischemic and hemorrhagic stroke,with an emphasis on their roles in oxidative stress,inflammation,and neuroprotection.展开更多
To efficiently remove radioactive nuclides from nuclear industry wastewater and minimize the generation of radioactive secondary waste,this study proposes the concept of a magnetically controlled microchannel adsorber...To efficiently remove radioactive nuclides from nuclear industry wastewater and minimize the generation of radioactive secondary waste,this study proposes the concept of a magnetically controlled microchannel adsorber based on magnetic adsorbents.A novel protocol for achieving high adsorption performance in microchannel adsorbers with periodically distributed particles is developed using the particle-resolved computational fluid dynamics (CFD) method,which addresses the limitations of traditional porous media flow models.To align simulation results more closely with practical scenarios,a typical high-efficiency magnetic adsorbent,magnetic sodium alginate/cobalt-based Prussian blue (M-SA/PB-Co),was synthesized.The M-SA/PB-Co microspheres exhibit a uniform size distribution (300–600 μm),and their Cs^(+) adsorption follows the pseudo-second-order kinetic model with a Langmuir saturated adsorption capacity of 124.84 mg·g^(-1).The performance parameters of M-SA/PB-Co,obtained from characterization and adsorption experiments,were integrated into CFD simulations.CFD results indicate that as the flow velocity increases,the flow field gradually transitions with vortices expanding in scale and streamline bifurcation points shifting rearward.The Cs^(+) concentration decreases progressively along the flow direction,with a more pronounced reduction in the vortex regions downstream of particles.The characteristic velocity and characteristic concentration of specific regions surrounding the particles were extracted based on boundary layer distribution.The amount of concentration reduction of Cs^(+) through particle is positively correlated with the characteristic concentration and negatively correlated with the characteristic velocity.The number of microspheres required in the microchannel adsorber was optimized using the response surface method.Compared with industrial fixed-bed adsorbers,microchannel adsorbers exhibit 8–10 times higher processing capacity,demonstrating significant industrial application potential.展开更多
Fine-grained nuclear graphite is a key material in high-temperature gas-cooled reactors(HTGRs).During air ingress accidents,core graphite components undergo severe oxidation,threatening structural integrity.Therefore,...Fine-grained nuclear graphite is a key material in high-temperature gas-cooled reactors(HTGRs).During air ingress accidents,core graphite components undergo severe oxidation,threatening structural integrity.Therefore,understanding the oxidation behavior of nuclear graphite is essential for reactor safety.The influence of oxidation involves multiple factors,including temperature,sample size,oxidant,impurities,filler type and size,etc.The size of the filler particles plays a crucial role in this study.Five ultrafine-and superfine-grained nuclear graphite samples(5.9-34.4μm)are manufactured using identical raw materials and manufacturing processes.Isothermal oxidation tests conducted at 650℃-750℃ are used to study the oxidation behavior.Additionally,comprehensive characterization is performed to analyze the crystal structure,surface morphology,and nanoscale to microscale pore structure of the samples.Results indicate that oxidation behavior cannot be predicted solely based on filler grain size.Reactive site concentration,characterized by active surface area,dominates the chemical reaction kinetics,whereas pore tortuosity,quantified by the structural parameterΨ,plays a key role in regulating oxidant diffusion.These findings clarify the dual role of microstructure in oxidation mechanisms and establish a theoretical and experimental basis for the design of high-performance nuclear graphite capable of long-term service in high-temperature gas-cooled reactors.展开更多
When the operating temperature of a solid oxide electrolysis cell(SOEC)is lower than the outlet temperature of a nuclear reactor,the reactor can be directly coupled with the SOEC as a high-temperature heat source.Howe...When the operating temperature of a solid oxide electrolysis cell(SOEC)is lower than the outlet temperature of a nuclear reactor,the reactor can be directly coupled with the SOEC as a high-temperature heat source.However,the key to the efficiency and return on investment of this hybrid energy system lies in the expected lifetime of the SOEC.This study assessed Ni-YSZ|YSZ|GDC|LSC fuel electrode support cells’long-term stability during electrolysis at 650℃with a current density of−0.5Acm^(−2)over 1818 h.The average voltage degradation rate of 2.63%kh^(−1)unfolded in two phases:an initial rapid decay(90 to 1120 h at 3.58%kh^(−1))and a stable decay(1120 to 1818 h at 2.14%kh^(−1)),emphasizing SOECs’probability coupling with nuclear reactors at 650℃.Post-1818-hour electrolysis revealed nickel particle formation associated with Ni(OH)_(x)diffusion and re-deposition,alongside a strontium-containing layer causing interface cracking.Despite minimal strontium segregation in the EDS,XPS data indicated surface segregation of Sr.This study provides crucial insights into prolonged SOEC operation,highlighting both its potential and challenges.展开更多
Nuclear heating plays an important aspect in design and deployment of both fission and fusion reactors and experimental devices in terms of cooling requirements. Two experimental campaigns in the framework of a collab...Nuclear heating plays an important aspect in design and deployment of both fission and fusion reactors and experimental devices in terms of cooling requirements. Two experimental campaigns in the framework of a collaboration project between the French Atomic and Alternative Energy Commission(CEA) and Jožef Stefan Institute(JSI), Slovenia, have been performed at the JSI TRIGA reactor for the experimental assessment of nuclear heating in fission and fusion-relevant materials by the differential calorimetry technique, based on the CALMOS and CARMEN differential calorimeters, previously developed at CEA. The results of the first campaign performed at reactor powers between 100 and 250 kW have already been reported, highlighting some measurement difficulties. Therefore, the second campaign was performed at a lower reactor power of 30 kW to overcome these issues. Moreover, a computational analysis of the experiments was performed using the JSIR2S code package to calculate the nuclear heating levels. Both experiments and their reproduction by simulations are described in detail. We present a comparison of the previously reported measured nuclear heating values of the first campaign with the computational results, with consistent underestimation by simulations by 8–35%. We report the experimental and computational results for the second experimental campaign performed at a reactor power of 30 kW. The simulated heating values were in agreement with the measurements within the measured heating uncertainty, with simulated heating 2.7–11.3% lower than the experimental values.展开更多
To clarify fluid flow mechanisms and establish effective development conditions in continental shale oil reservoirs,a high-temperature,high-pressure steady-state flow system integrated with nuclear magnetic resonance(...To clarify fluid flow mechanisms and establish effective development conditions in continental shale oil reservoirs,a high-temperature,high-pressure steady-state flow system integrated with nuclear magnetic resonance(NMR)technology has been developed.The apparatus combines sample evacuation,rapid pressurization and saturation,and controlled displacement,enabling systematic investigation of single-phase shale oil flow under representative reservoir conditions.Related experiments allow proper quantification of the activation thresholds and relative contributions of different pore types to flow.A movable fluid index(MFI),defined using dual T_(2) cutoff values,is introduced accordingly and linked to key flow parameters.The results reveal distinct multi-scale characteristics of single-phase shale oil transport,namely micro-scale graded displacement and macro-scale segmented nonlinear behavior.As the injection-production pressure difference increases,flow pathways are activated progressively,beginning with fractures,followed by large and then smaller macropores,leading to a pronounced enhancement in apparent permeability.Although mesopores and micropores contribute little to direct flow,their indirect influence becomes increasingly important,and apparent permeability gradually approaches a stable limit at higher pressure difference.It is also shown that the MFI exhibits a strong negative correlation with the starting pressure gradient and a positive correlation with apparent permeability,providing a rapid and reliable indicator of shale oil flow capacity.Samples containing through-going fractures display consistently higher MFI values and superior flowability compared with those dominated by laminated fractures,highlighting the pivotal role of well-connected fracture networks generated by large-scale hydraulic fracturing in improving shale oil production.展开更多
The process of nuclear fusion in the presence of a laser field was theoretically analyzed.The analysis is applicable to most fusion reactions and different types of currently available intense lasers,from X-ray free-e...The process of nuclear fusion in the presence of a laser field was theoretically analyzed.The analysis is applicable to most fusion reactions and different types of currently available intense lasers,from X-ray free-electron lasers to solid-state near-infrared lasers.Laser fields were shown to enhance the fusion yields,and the mechanism of this enhancement was explained.Low-frequency lasers are more efficient in enhancing fusion than high-frequency lasers.The calculation results show enhancements of fusion yields by orders of magnitude with currently available intense low-frequency laser fields.The temperature requirement for controlled nuclear fusion may be reduced with the aid of intense laser fields.展开更多
The Fujian oyster(Crassostrea angulata) is an economically significant shellfish species distributed mainly along the Fujian coast, Southeast China. However, its genetic diversity and structure remain unclear. The mai...The Fujian oyster(Crassostrea angulata) is an economically significant shellfish species distributed mainly along the Fujian coast, Southeast China. However, its genetic diversity and structure remain unclear. The main distribution area of the C. angulata is located in Fujian, South China. In total, 420 C. angulata were collected from 14 natural habitats(populations) along the Fujian coast, and their genetic diversity and structure were analyzed in the mitochondrial COI and nuclear gene ITS2 sequences. Results reveal that all the 14 populations of C. angulata exhibited high levels of genetic diversity, with a total of 57(haplotype diversity: 0.811±0.016) and 124(haplotype diversity: 0.912±0.007) haplotypes revealed by COI and ITS2, respectively. Notably, significant intermediate level of genetic differentiations between the Ningde Zhujiang(ZJ) population(FS T by COI: 0.035–0.142, P<0.05;FS T by ITS2: 0.078–0.123, P<0.05) with other populations were observed for the first time, which is also supported by the results of molecular variance analysis(FC T by COI: 0.105, P<0.05;FC T by ITS2: 0.086, P<0.05) and the clustering of the ZJ population into distinct branches in the interpopulation genetic differentiation tree. Furthermore, the evolutionary tree and haplotype network analyses do not support the formation of a clear geographical genealogical structure among these 14 populations. In addition, the population dynamics analysis suggests that the C. angulata may have undergone expansion during the third ice age of the Pleistocene. These results provide a reference for the preservation and further genetic improvement of C. angulata.展开更多
Recent advances in atomic optical clocks based on electronic transitions have achieved frequency uncertainties at the10^(-19)level,enabling wide applications in testing variations of physical constants,exploring dark ...Recent advances in atomic optical clocks based on electronic transitions have achieved frequency uncertainties at the10^(-19)level,enabling wide applications in testing variations of physical constants,exploring dark matter signatures,and enhancing precision metrology for position,navigation,and timing systems.To pursue higher-precision optical clocks,the development of nuclear optical clocks has emerged,with the^(229)Th system distinguished by its unique low-lying isomeric state at~8.4 eV and a natural linewidth of approximately 100μHz,promising uncertainties below 10^(-19).The intrinsic insensitivity of nuclear transitions to external perturbations and their subatomic-scale spatial confinement provide significant advantages over electronic transitions in mitigating environmental shifts.Recent experimental breakthroughs include the excitation of the nuclear clock transition in solid-state^(229)Th-doped crystals with spectral resolution at the k Hz level.However,critical challenges persist,particularly in implementing effective laser excitation schemes(e.g.,via the electronic bridge mechanism)and closed-loop quantum control in trapped ion systems.Addressing these requires comprehensive understanding of complex many-body interactions in^(229)Th,encompassing electronic structure,nuclear deformation,hyperfine and field shift,and solid-state environmental coupling.This review synthesizes recent advancements in(i)the characterization of nuclear and atomic structures of the^(229)Th nuclear clock,and(ii)precise evaluation and mitigation of external perturbations affecting the clock transitions.The analysis provides a solid theoretical and experimental foundation for optimizing^(229)Th-based nuclear clock performance.展开更多
Owing to the presence of a low-energy,long-lived nuclear isomeric state,^(229)Th is an ideal candidate for developing the next generation clock—the nuclear clock—holding great promise for both applied and fundamenta...Owing to the presence of a low-energy,long-lived nuclear isomeric state,^(229)Th is an ideal candidate for developing the next generation clock—the nuclear clock—holding great promise for both applied and fundamental physics.The^(229)Th ionic nuclear optical clock has garnered considerable attention,attributed to its high precision with a relative uncertainty of≤1.5×10^(-19)and the potential for common-mode noise cancellation via self-comparison between the nuclear transition and the electronic transition of thorium ions.In this article,we focus on Th^(n+)ions(n=1,2,3)and present a comprehensive review of the current progress in the development of ionic nuclear clocks,covering essential steps such as ion generation,trapping,and cooling.Furthermore,we discuss the realization of a closed-loop clock cycle,addressing key aspects including stable isomer excitation and efficient isomer deexcitation.展开更多
When discussing atomic nuclei,deformation is one of the most common topics.However,when we connect the concept of shape with high-precision experimental measurements,sometimes the explanation may not be as simple as w...When discussing atomic nuclei,deformation is one of the most common topics.However,when we connect the concept of shape with high-precision experimental measurements,sometimes the explanation may not be as simple as we think.A recent measurement of nuclear charge radii(Phys.Rev.Lett.134,182501(2025))challenges current nuclear ab initio models.展开更多
In a series of three papers published in 2024[1-3],physicists in Austria,Germany,and the United States reported the first direct observations with table-top lasers of a new nuclear process,in which the nucleus of a th...In a series of three papers published in 2024[1-3],physicists in Austria,Germany,and the United States reported the first direct observations with table-top lasers of a new nuclear process,in which the nucleus of a thorium atom absorbs a photon and goes into an excited state,then re-emits the photon and returns to its ground state.This“thorescence”phenomenon“is exactly the same process as fluorescence,but it takes place inside the nucleus,”said Ekkehard Peik,professor and head of the department of time and frequency at the Physikalisch-Technische Bundesanstalt(the German national metrology institute)in Braunschweig,Germany.展开更多
Additive manufacturing(AM)is an innovative technique that enables the flexible design and construction of three-dimensional objects.In the nuclear industry,AM enables the use of advanced materials and high-performance...Additive manufacturing(AM)is an innovative technique that enables the flexible design and construction of three-dimensional objects.In the nuclear industry,AM enables the use of advanced materials and high-performance components.Although AM processing has been extensively investigated,the corresponding mechanical properties and structural integrity issues of AM parts have received less attention.This study reviews the mechanical behavior and key challenges of typical AM materials,fuel components,compact heat exchangers with complex geometries,and additive repair of damaged reactor components.The findings of this review will guide the efficient and reliable implementation of AM techniques in nuclear reactors.展开更多
Amborella trichopoda(Amborellaceae;hereafter simply Amborella)(Fig.1A)is a shrub endemic to New Caledonia in the Southwest Pacific that represents the sole sister species of all other extant angiosperms(Qiu et al.,199...Amborella trichopoda(Amborellaceae;hereafter simply Amborella)(Fig.1A)is a shrub endemic to New Caledonia in the Southwest Pacific that represents the sole sister species of all other extant angiosperms(Qiu et al.,1999;One Thousand Plant Transcriptomes Initiative,2019).Due to its unique phylogenetic status,it holds tremendous interest for botanists.The nuclear and mitochondrial genomes of Amborella were first published in 2013,providing valuable resources for studies on genome and gene family evolution,phylogenomics,and flower development,despite the fact that the assembly is heavily fragmented(Amborella Genome Project,2013;Rice et al.,2013).In 2024,a haplotype-resolved Amborella genome assembly was published,showing significant improvement in quality and completeness(Carey et al.,2024).展开更多
Nuclear magnetic resonance(NMR)spectroscopy is a powerful and broadly used spectroscopic technique for characterizing molecular structures and dynamics.Yet the power of NMR is restricted by its inherently low sensitiv...Nuclear magnetic resonance(NMR)spectroscopy is a powerful and broadly used spectroscopic technique for characterizing molecular structures and dynamics.Yet the power of NMR is restricted by its inherently low sensitivity due to the weak polarization of nuclear spins under conventional experiment conditions.Dynamic nuclear polarization(DNP)and chemically induced dynamic nuclear polarization(CIDNP)have been emerging as powerful in-situ hyperpolarization methods to boost NMR sensitivity.This review provides a brief overview of DNP mechanisms in the context of both solid-state and liquidstate.We delve into the molecular features of different polarizing agents and their impacts on DNP applications,which are now steadily progressing towards modern NMR magnetic field strengths and ambient temperatures.Furthermore,the progress of CIDNP,particularly photo-CIDNP as a potential alternative hyperpolarization technique of DNP,in studying protein dynamics and chemical reaction mechanisms,will be covered.This review also highlights the chemical diversity and experimental strategies crucial for these hyperpolarization techniques,showcasing their transformative role in NMR spectroscopy.展开更多
The^(229)Th nuclear optical clocks,operating via the 8.4 eV nuclear transition,hold great promise for attaining unprecedented accuracy in frequency standards and fundamental physics tests.In this study,we propose an a...The^(229)Th nuclear optical clocks,operating via the 8.4 eV nuclear transition,hold great promise for attaining unprecedented accuracy in frequency standards and fundamental physics tests.In this study,we propose an approach that utilizes highly charged^(229)Th^(6+)ions as the platform for nuclear clock,which exhibits simple electronic energy structures and enhanced nucleus–electron coupling compared to low-charge Th ions.The^(3)P_(2)↔^(3)P_(0)ionic clock transition in^(229)Th^(6+)ions has the potential to serve as a probe for nuclear structure.Moreover,we predict the existence of two excited electronic states near and slightly above the nuclear clock state,which can serve as the intermediate states in the optical repumping process.We estimate the Rabi frequencies of the electronic bridge transitions from the nuclear clock state to these intermediate states and further analyze the population dynamics of the optical repumping process,which can be completed on the millisecond timescale.Our results demonstrate the advantages of using^(229)Th^(6+)ions as the promising platform for nuclear clock.展开更多
We investigated the correlations between the net baryon number and electric charge up to the sixth order related to the interactions of nuclear matter at low temperature and explored their relationship with the nuclea...We investigated the correlations between the net baryon number and electric charge up to the sixth order related to the interactions of nuclear matter at low temperature and explored their relationship with the nuclear liquid-gas phase transition(LGPT)within the framework of the nonlinear Walecka model.The calculations showed that strong correlations between the baryon number and electric charge existed near the LGPT,and higher-order correlations were more sensitive than the lower-order correlations near the phase transition.However,in the high-temperature region away from the LGPT,the rescaled lower-order correlations were relatively larger than most of the higher-order correlations.In addition,some of the fifth-and sixth-order correlations possibly changed sign from negative to positive along the chemical freeze-out line with decreasing temperature.In combination with future experimental projects at lower collision energies,the derived results can be used to study the phase structure of strongly interacting matter and analyze the related experimental signals.展开更多
Pancreatic ductal adenocarcinoma (PDAC) is a devastating disease with a median overall survival time of 5 mo and the five years survival less than 5%, a rate essentially unchanged over the course of the years. A well ...Pancreatic ductal adenocarcinoma (PDAC) is a devastating disease with a median overall survival time of 5 mo and the five years survival less than 5%, a rate essentially unchanged over the course of the years. A well defined progression model of accumulation of genetic alterations ranging from single point mutations to gross chromosomal abnormalities has been introduced to describe the origin of this disease. However, due to the its subtle nature and concurring events PDAC cure remains elusive. Nuclear receptors (NR) are members of a large superfamily of evolutionarily conserved ligand-regulated DNA-binding transcription factors functionally involved in important cellular functions ranging from regulation of metabolism, to growth and development. Given the nature of their ligands, NR are very tempting drug targets and their pharmacological modulation has been widely exploited for the treatment of metabolic and inflammatory diseases. There are now clear evidences that both classical ligand-activated and orphan NR are involved in the pathogenesis of PDAC from its very early stages; nonetheless many aspects of their role are not fully understood. The purpose of this review is to highlight the striking connections that link peroxisome proliferator activated receptors, retinoic acid receptors, retinoid X receptor, androgen receptor, estrogen receptors and the orphan NR Nur, chicken ovalbumin upstream promoter transcription factor II and the liver receptor homologue-1 receptor to PDAC development, connections that could lead to the identification of novel therapies for this disease.展开更多
A microgravity environment has been shown to cause ocular damage and affect visual acuity,but the underlying mechanisms remain unclear.Therefore,we established an animal model of weightlessness via tail suspension to ...A microgravity environment has been shown to cause ocular damage and affect visual acuity,but the underlying mechanisms remain unclear.Therefore,we established an animal model of weightlessness via tail suspension to examine the pathological changes and molecular mechanisms of retinal damage under microgravity.After 4 weeks of tail suspension,there were no notable alterations in retinal function and morphology,while after 8 weeks of tail suspension,significant reductions in retinal function were observed,and the outer nuclear layer was thinner,with abundant apoptotic cells.To investigate the mechanism underlying the degenerative changes that occurred in the outer nuclear layer of the retina,proteomics was used to analyze differentially expressed proteins in rat retinas after 8 weeks of tail suspension.The results showed that the expression levels of fibroblast growth factor 2(also known as basic fibroblast growth factor)and glial fibrillary acidic protein,which are closely related to Müller cell activation,were significantly upregulated.In addition,Müller cell regeneration and Müller cell gliosis were observed after 4 and 8 weeks,respectively,of simulated weightlessness.These findings indicate that Müller cells play an important regulatory role in retinal outer nuclear layer degeneration during weightlessness.展开更多
基金supported by the National Natural Science Foundation of China (Grant Nos.12475012,62461160263 for P.W.,and 62276171 for H.L.)Quantum Science and Technology-National Science and Technology Major Project of China (Project No.2023ZD0300600 for P.W.)+3 种基金Guangdong Provincial Quantum Science Strategic Initiative (Grant Nos.GDZX240-3009 and GDZX2303005 for P.W.)Guangdong Basic and Applied Basic Research Foundation (Grant No.2024-A1515011938 for H.L.)Shenzhen Fundamental ResearchGeneral Project (Grant No.JCYJ20240813141503005 for H.L.)the Talents Introduction Foundation of Beijing Normal University (Grant No.310432106 for P.W.)。
文摘Hyperpolarization of nuclear spins is crucial for advancing nuclear magnetic resonance and quantum information technologies,as nuclear spins typically exhibit extremely low polarization at room temperature due to their small gyromagnetic ratios.A promising approach to achieving high nuclear spin polarization is transferring the polarization of electrons to nuclear spins.The nitrogen-vacancy(NV)center in diamond has emerged as a highly effective medium for this purpose,and various hyperpolarization protocols have been developed.Among these,the pulsed polarization(PulsePol)method has been extensively studied due to its robustness against static energy shifts of the electron spin.In this work,we present a novel polarization protocol and uncover a family of magic sequences for hyperpolarizing nuclear spins,with PulsePol emerging as a special case of our general approach.Notably,we demonstrate that some of these magic sequences exhibit significantly greater robustness compared to the PulsePol protocol in the presence of finite half𝜋pulse duration of the protocol,Rabi and detuning errors.This enhanced robustness positions our protocol as a more suitable candidate for hyper-polarizing nuclear spins species with large gyromagnetic ratios and also ensures better compatibility with high-efficiency readout techniques at high magnetic fields.Additionally,the generality of our protocol allows for its direct application to other solid-state quantum systems beyond the NV center.
基金supported by grants from the Zhejiang Provincial TCM Science and Technology Plan Project,No.2023ZL156(to YH)Ningbo Top Medical and Health Research Program,No.2022020304(to XG)+1 种基金the Natural Science Foundation of Ningbo,No.2023J019(to YH)Key Laboratory of Precision Medicine for Atherosclerotic Diseases of Zhejiang Province,No.2022E10026(to YH)。
文摘Strokes include both ischemic stroke,which is mediated by a blockade or reduction in the blood supply to the brain,and hemorrhagic stroke,which comprises intracerebral hemorrhage and subarachnoid hemorrhage and is characterized by bleeding within the brain.Stroke is a lifethreatening cerebrovascular condition characterized by intricate pathophysiological mechanisms,including oxidative stress,inflammation,mitochondrial dysfunction,and neuronal injury.Critical transcription factors,such as nuclear factor erythroid 2-related factor 2 and nuclear factor kappa B,play central roles in the progression of stroke.Nuclear factor erythroid 2-related factor 2 is sensitive to changes in the cellular redox status and is crucial in protecting cells against oxidative damage,inflammatory responses,and cytotoxic agents.It plays a significant role in post-stroke neuroprotection and repair by influencing mitochondrial function,endoplasmic reticulum stress,and lysosomal activity and regulating metabolic pathways and cytokine expression.Conversely,nuclear factor-kappa B is closely associated with mitochondrial dysfunction,the generation of reactive oxygen species,oxidative stress exacerbation,and inflammation.Nuclear factor-kappa B contributes to neuronal injury,apoptosis,and immune responses following stroke by modulating cell adhesion molecules and inflammatory mediators.The interplay between these pathways,potentially involving crosstalk among various organelles,significantly influences stroke pathophysiology.Advancements in single-cell sequencing and spatial transcriptomics have greatly improved our understanding of stroke pathogenesis and offer new opportunities for the development of targeted,individualized,cell typespecific treatments.In this review,we discuss the mechanisms underlying the involvement of nuclear factor erythroid 2-related factor 2 and nuclear factor-kappa B in both ischemic and hemorrhagic stroke,with an emphasis on their roles in oxidative stress,inflammation,and neuroprotection.
基金Dalian distinguished young scholars program(2022RJ17)the Dalian excellent young talents program(2023RY037)provided funding for this study.
文摘To efficiently remove radioactive nuclides from nuclear industry wastewater and minimize the generation of radioactive secondary waste,this study proposes the concept of a magnetically controlled microchannel adsorber based on magnetic adsorbents.A novel protocol for achieving high adsorption performance in microchannel adsorbers with periodically distributed particles is developed using the particle-resolved computational fluid dynamics (CFD) method,which addresses the limitations of traditional porous media flow models.To align simulation results more closely with practical scenarios,a typical high-efficiency magnetic adsorbent,magnetic sodium alginate/cobalt-based Prussian blue (M-SA/PB-Co),was synthesized.The M-SA/PB-Co microspheres exhibit a uniform size distribution (300–600 μm),and their Cs^(+) adsorption follows the pseudo-second-order kinetic model with a Langmuir saturated adsorption capacity of 124.84 mg·g^(-1).The performance parameters of M-SA/PB-Co,obtained from characterization and adsorption experiments,were integrated into CFD simulations.CFD results indicate that as the flow velocity increases,the flow field gradually transitions with vortices expanding in scale and streamline bifurcation points shifting rearward.The Cs^(+) concentration decreases progressively along the flow direction,with a more pronounced reduction in the vortex regions downstream of particles.The characteristic velocity and characteristic concentration of specific regions surrounding the particles were extracted based on boundary layer distribution.The amount of concentration reduction of Cs^(+) through particle is positively correlated with the characteristic concentration and negatively correlated with the characteristic velocity.The number of microspheres required in the microchannel adsorber was optimized using the response surface method.Compared with industrial fixed-bed adsorbers,microchannel adsorbers exhibit 8–10 times higher processing capacity,demonstrating significant industrial application potential.
基金supported by the National Key Research and Development Program of China(2024YFA1612900)the National Natural Science Foundation of China(Grant No.52103365 and No.12375270)the Guangdong Innovative and Entrepreneurial Research Team Program,China(Grant No.2021ZT09L227).
文摘Fine-grained nuclear graphite is a key material in high-temperature gas-cooled reactors(HTGRs).During air ingress accidents,core graphite components undergo severe oxidation,threatening structural integrity.Therefore,understanding the oxidation behavior of nuclear graphite is essential for reactor safety.The influence of oxidation involves multiple factors,including temperature,sample size,oxidant,impurities,filler type and size,etc.The size of the filler particles plays a crucial role in this study.Five ultrafine-and superfine-grained nuclear graphite samples(5.9-34.4μm)are manufactured using identical raw materials and manufacturing processes.Isothermal oxidation tests conducted at 650℃-750℃ are used to study the oxidation behavior.Additionally,comprehensive characterization is performed to analyze the crystal structure,surface morphology,and nanoscale to microscale pore structure of the samples.Results indicate that oxidation behavior cannot be predicted solely based on filler grain size.Reactive site concentration,characterized by active surface area,dominates the chemical reaction kinetics,whereas pore tortuosity,quantified by the structural parameterΨ,plays a key role in regulating oxidant diffusion.These findings clarify the dual role of microstructure in oxidation mechanisms and establish a theoretical and experimental basis for the design of high-performance nuclear graphite capable of long-term service in high-temperature gas-cooled reactors.
基金supported by the Strategic Priority Research Program of the Chinese Academy of Sciences(No.XDA0400000),the Youth Innovation Promotion Association of the Chinese Academy of Sciences(No.2021253)+1 种基金the Major Science and Technology Projects of China National Offshore Oil Corporation Limited during the 14th Five Year Plan(No.KJGG-2022-12-CCUS-030500)the Photon Science Center for Carbon Neutrality of Chinese Academy of Science.
文摘When the operating temperature of a solid oxide electrolysis cell(SOEC)is lower than the outlet temperature of a nuclear reactor,the reactor can be directly coupled with the SOEC as a high-temperature heat source.However,the key to the efficiency and return on investment of this hybrid energy system lies in the expected lifetime of the SOEC.This study assessed Ni-YSZ|YSZ|GDC|LSC fuel electrode support cells’long-term stability during electrolysis at 650℃with a current density of−0.5Acm^(−2)over 1818 h.The average voltage degradation rate of 2.63%kh^(−1)unfolded in two phases:an initial rapid decay(90 to 1120 h at 3.58%kh^(−1))and a stable decay(1120 to 1818 h at 2.14%kh^(−1)),emphasizing SOECs’probability coupling with nuclear reactors at 650℃.Post-1818-hour electrolysis revealed nickel particle formation associated with Ni(OH)_(x)diffusion and re-deposition,alongside a strontium-containing layer causing interface cracking.Despite minimal strontium segregation in the EDS,XPS data indicated surface segregation of Sr.This study provides crucial insights into prolonged SOEC operation,highlighting both its potential and challenges.
基金supported by the Slovenian Research Agency(research project NC-0001-Analysis of nuclear heating in a reactor,research core funding Reactor physics No.P2-0073,infrastructure program I0-0005)。
文摘Nuclear heating plays an important aspect in design and deployment of both fission and fusion reactors and experimental devices in terms of cooling requirements. Two experimental campaigns in the framework of a collaboration project between the French Atomic and Alternative Energy Commission(CEA) and Jožef Stefan Institute(JSI), Slovenia, have been performed at the JSI TRIGA reactor for the experimental assessment of nuclear heating in fission and fusion-relevant materials by the differential calorimetry technique, based on the CALMOS and CARMEN differential calorimeters, previously developed at CEA. The results of the first campaign performed at reactor powers between 100 and 250 kW have already been reported, highlighting some measurement difficulties. Therefore, the second campaign was performed at a lower reactor power of 30 kW to overcome these issues. Moreover, a computational analysis of the experiments was performed using the JSIR2S code package to calculate the nuclear heating levels. Both experiments and their reproduction by simulations are described in detail. We present a comparison of the previously reported measured nuclear heating values of the first campaign with the computational results, with consistent underestimation by simulations by 8–35%. We report the experimental and computational results for the second experimental campaign performed at a reactor power of 30 kW. The simulated heating values were in agreement with the measurements within the measured heating uncertainty, with simulated heating 2.7–11.3% lower than the experimental values.
基金supported by the National Science and Technology Major Project of China(Grant No.2024ZD 1004302)the Key Scientific and Technological Research project of SINOPEC(Grant No.P25186).
文摘To clarify fluid flow mechanisms and establish effective development conditions in continental shale oil reservoirs,a high-temperature,high-pressure steady-state flow system integrated with nuclear magnetic resonance(NMR)technology has been developed.The apparatus combines sample evacuation,rapid pressurization and saturation,and controlled displacement,enabling systematic investigation of single-phase shale oil flow under representative reservoir conditions.Related experiments allow proper quantification of the activation thresholds and relative contributions of different pore types to flow.A movable fluid index(MFI),defined using dual T_(2) cutoff values,is introduced accordingly and linked to key flow parameters.The results reveal distinct multi-scale characteristics of single-phase shale oil transport,namely micro-scale graded displacement and macro-scale segmented nonlinear behavior.As the injection-production pressure difference increases,flow pathways are activated progressively,beginning with fractures,followed by large and then smaller macropores,leading to a pronounced enhancement in apparent permeability.Although mesopores and micropores contribute little to direct flow,their indirect influence becomes increasingly important,and apparent permeability gradually approaches a stable limit at higher pressure difference.It is also shown that the MFI exhibits a strong negative correlation with the starting pressure gradient and a positive correlation with apparent permeability,providing a rapid and reliable indicator of shale oil flow capacity.Samples containing through-going fractures display consistently higher MFI values and superior flowability compared with those dominated by laminated fractures,highlighting the pivotal role of well-connected fracture networks generated by large-scale hydraulic fracturing in improving shale oil production.
基金supported by the National Natural Science Foundation of China(Nos.12405288,12374241,12474484,U2330401,12088101)the Natural Science Foundation of Top Talent of SZTU(No.GDRC202526)。
文摘The process of nuclear fusion in the presence of a laser field was theoretically analyzed.The analysis is applicable to most fusion reactions and different types of currently available intense lasers,from X-ray free-electron lasers to solid-state near-infrared lasers.Laser fields were shown to enhance the fusion yields,and the mechanism of this enhancement was explained.Low-frequency lasers are more efficient in enhancing fusion than high-frequency lasers.The calculation results show enhancements of fusion yields by orders of magnitude with currently available intense low-frequency laser fields.The temperature requirement for controlled nuclear fusion may be reduced with the aid of intense laser fields.
基金Supported by the National Natural Science Foundation of China(No.32172979)the Natural Science Foundation of Fujian Province(No.2021J05159)the 2023 Special Program for Promoting High-Quality Development of Marine and Fishery Industry in Fujian Province(No.PJHYF-L-2023-2)。
文摘The Fujian oyster(Crassostrea angulata) is an economically significant shellfish species distributed mainly along the Fujian coast, Southeast China. However, its genetic diversity and structure remain unclear. The main distribution area of the C. angulata is located in Fujian, South China. In total, 420 C. angulata were collected from 14 natural habitats(populations) along the Fujian coast, and their genetic diversity and structure were analyzed in the mitochondrial COI and nuclear gene ITS2 sequences. Results reveal that all the 14 populations of C. angulata exhibited high levels of genetic diversity, with a total of 57(haplotype diversity: 0.811±0.016) and 124(haplotype diversity: 0.912±0.007) haplotypes revealed by COI and ITS2, respectively. Notably, significant intermediate level of genetic differentiations between the Ningde Zhujiang(ZJ) population(FS T by COI: 0.035–0.142, P<0.05;FS T by ITS2: 0.078–0.123, P<0.05) with other populations were observed for the first time, which is also supported by the results of molecular variance analysis(FC T by COI: 0.105, P<0.05;FC T by ITS2: 0.086, P<0.05) and the clustering of the ZJ population into distinct branches in the interpopulation genetic differentiation tree. Furthermore, the evolutionary tree and haplotype network analyses do not support the formation of a clear geographical genealogical structure among these 14 populations. In addition, the population dynamics analysis suggests that the C. angulata may have undergone expansion during the third ice age of the Pleistocene. These results provide a reference for the preservation and further genetic improvement of C. angulata.
基金supported by the Strategic Priority Research Program of the Chinese Academy of Sciences(Grant Nos.XDB0920100 and XDB0920101)the National Natural Science Foundation of China(Grant Nos.12174402,12393821,12274417)the Chinese Academy of Sciences Project for Young Scientists in Basic Research(Grant No.YSBR-055)。
文摘Recent advances in atomic optical clocks based on electronic transitions have achieved frequency uncertainties at the10^(-19)level,enabling wide applications in testing variations of physical constants,exploring dark matter signatures,and enhancing precision metrology for position,navigation,and timing systems.To pursue higher-precision optical clocks,the development of nuclear optical clocks has emerged,with the^(229)Th system distinguished by its unique low-lying isomeric state at~8.4 eV and a natural linewidth of approximately 100μHz,promising uncertainties below 10^(-19).The intrinsic insensitivity of nuclear transitions to external perturbations and their subatomic-scale spatial confinement provide significant advantages over electronic transitions in mitigating environmental shifts.Recent experimental breakthroughs include the excitation of the nuclear clock transition in solid-state^(229)Th-doped crystals with spectral resolution at the k Hz level.However,critical challenges persist,particularly in implementing effective laser excitation schemes(e.g.,via the electronic bridge mechanism)and closed-loop quantum control in trapped ion systems.Addressing these requires comprehensive understanding of complex many-body interactions in^(229)Th,encompassing electronic structure,nuclear deformation,hyperfine and field shift,and solid-state environmental coupling.This review synthesizes recent advancements in(i)the characterization of nuclear and atomic structures of the^(229)Th nuclear clock,and(ii)precise evaluation and mitigation of external perturbations affecting the clock transitions.The analysis provides a solid theoretical and experimental foundation for optimizing^(229)Th-based nuclear clock performance.
基金Project supported by the Strategic Priority Research Program of the Chinese Academy of Sciences(Grant No.XDB0920000)the National Natural Science Foundation of China(Grant No.12341401)。
文摘Owing to the presence of a low-energy,long-lived nuclear isomeric state,^(229)Th is an ideal candidate for developing the next generation clock—the nuclear clock—holding great promise for both applied and fundamental physics.The^(229)Th ionic nuclear optical clock has garnered considerable attention,attributed to its high precision with a relative uncertainty of≤1.5×10^(-19)and the potential for common-mode noise cancellation via self-comparison between the nuclear transition and the electronic transition of thorium ions.In this article,we focus on Th^(n+)ions(n=1,2,3)and present a comprehensive review of the current progress in the development of ionic nuclear clocks,covering essential steps such as ion generation,trapping,and cooling.Furthermore,we discuss the realization of a closed-loop clock cycle,addressing key aspects including stable isomer excitation and efficient isomer deexcitation.
基金supported by the National Natural Science Foundation of China(No.12235003).
文摘When discussing atomic nuclei,deformation is one of the most common topics.However,when we connect the concept of shape with high-precision experimental measurements,sometimes the explanation may not be as simple as we think.A recent measurement of nuclear charge radii(Phys.Rev.Lett.134,182501(2025))challenges current nuclear ab initio models.
文摘In a series of three papers published in 2024[1-3],physicists in Austria,Germany,and the United States reported the first direct observations with table-top lasers of a new nuclear process,in which the nucleus of a thorium atom absorbs a photon and goes into an excited state,then re-emits the photon and returns to its ground state.This“thorescence”phenomenon“is exactly the same process as fluorescence,but it takes place inside the nucleus,”said Ekkehard Peik,professor and head of the department of time and frequency at the Physikalisch-Technische Bundesanstalt(the German national metrology institute)in Braunschweig,Germany.
基金supported by Stable Support Initiative of the State Key Laboratory of Advanced Nuclear Energy Technology(Grant No.YNSW-0124-0101-03)the author Cheng Zhang would like to thank the support by Stable Support Program for Scientific Research of China(Grant No.WDZC-2023-02-02-05).
文摘Additive manufacturing(AM)is an innovative technique that enables the flexible design and construction of three-dimensional objects.In the nuclear industry,AM enables the use of advanced materials and high-performance components.Although AM processing has been extensively investigated,the corresponding mechanical properties and structural integrity issues of AM parts have received less attention.This study reviews the mechanical behavior and key challenges of typical AM materials,fuel components,compact heat exchangers with complex geometries,and additive repair of damaged reactor components.The findings of this review will guide the efficient and reliable implementation of AM techniques in nuclear reactors.
基金supported by the National Natural Science Foundation of China(32270217,31970205,31770211)Metasequoia funding of Nanjing Forestry University to YY。
文摘Amborella trichopoda(Amborellaceae;hereafter simply Amborella)(Fig.1A)is a shrub endemic to New Caledonia in the Southwest Pacific that represents the sole sister species of all other extant angiosperms(Qiu et al.,1999;One Thousand Plant Transcriptomes Initiative,2019).Due to its unique phylogenetic status,it holds tremendous interest for botanists.The nuclear and mitochondrial genomes of Amborella were first published in 2013,providing valuable resources for studies on genome and gene family evolution,phylogenomics,and flower development,despite the fact that the assembly is heavily fragmented(Amborella Genome Project,2013;Rice et al.,2013).In 2024,a haplotype-resolved Amborella genome assembly was published,showing significant improvement in quality and completeness(Carey et al.,2024).
基金supported by the National Natural Science Foundation of China(Grant No.22403029)the Postdoctoral Fellowship Program of China Postdoctoral Science Foundation(Grant No.GZC20240475,2024M760922)+5 种基金supported by National Natural Science Foundation of China(Grant No.22174099)supported by the National Natural Science Foundation of China(Grant No.22273023)the National Key R&D Program of China(Grant No.2019YFA0905200)Shanghai Municipal Natural Science Foundation(Grant No.23ZR1418200)Natural Science Foundation of Chongqing,China(Grant No.CSTB2023NSCQ-MSX0616)Shanghai Frontiers Science Center of Molecule Intelligent Syntheses,and the Fundamental Research Funds for the Central Universities.
文摘Nuclear magnetic resonance(NMR)spectroscopy is a powerful and broadly used spectroscopic technique for characterizing molecular structures and dynamics.Yet the power of NMR is restricted by its inherently low sensitivity due to the weak polarization of nuclear spins under conventional experiment conditions.Dynamic nuclear polarization(DNP)and chemically induced dynamic nuclear polarization(CIDNP)have been emerging as powerful in-situ hyperpolarization methods to boost NMR sensitivity.This review provides a brief overview of DNP mechanisms in the context of both solid-state and liquidstate.We delve into the molecular features of different polarizing agents and their impacts on DNP applications,which are now steadily progressing towards modern NMR magnetic field strengths and ambient temperatures.Furthermore,the progress of CIDNP,particularly photo-CIDNP as a potential alternative hyperpolarization technique of DNP,in studying protein dynamics and chemical reaction mechanisms,will be covered.This review also highlights the chemical diversity and experimental strategies crucial for these hyperpolarization techniques,showcasing their transformative role in NMR spectroscopy.
基金supported by the Strategic Priority Research Program of the Chinese Academy of Sciences(Grant No.XDB0920000)the National Key Research and Development Program of China(Grant No.2022YFB3904002)the National Natural Science Foundation of China(Grant No.12341401)。
文摘The^(229)Th nuclear optical clocks,operating via the 8.4 eV nuclear transition,hold great promise for attaining unprecedented accuracy in frequency standards and fundamental physics tests.In this study,we propose an approach that utilizes highly charged^(229)Th^(6+)ions as the platform for nuclear clock,which exhibits simple electronic energy structures and enhanced nucleus–electron coupling compared to low-charge Th ions.The^(3)P_(2)↔^(3)P_(0)ionic clock transition in^(229)Th^(6+)ions has the potential to serve as a probe for nuclear structure.Moreover,we predict the existence of two excited electronic states near and slightly above the nuclear clock state,which can serve as the intermediate states in the optical repumping process.We estimate the Rabi frequencies of the electronic bridge transitions from the nuclear clock state to these intermediate states and further analyze the population dynamics of the optical repumping process,which can be completed on the millisecond timescale.Our results demonstrate the advantages of using^(229)Th^(6+)ions as the promising platform for nuclear clock.
基金supported by the National Natural Science Foundation of China(Nos.12475145,11875213)the Natural Science Basic Research Plan in Shaanxi Province of China(No.2024JC-YBMS-018).
文摘We investigated the correlations between the net baryon number and electric charge up to the sixth order related to the interactions of nuclear matter at low temperature and explored their relationship with the nuclear liquid-gas phase transition(LGPT)within the framework of the nonlinear Walecka model.The calculations showed that strong correlations between the baryon number and electric charge existed near the LGPT,and higher-order correlations were more sensitive than the lower-order correlations near the phase transition.However,in the high-temperature region away from the LGPT,the rescaled lower-order correlations were relatively larger than most of the higher-order correlations.In addition,some of the fifth-and sixth-order correlations possibly changed sign from negative to positive along the chemical freeze-out line with decreasing temperature.In combination with future experimental projects at lower collision energies,the derived results can be used to study the phase structure of strongly interacting matter and analyze the related experimental signals.
基金Supported by Fondo per gli Investimenti della Ricerca di Base(FIRB)(RBAP10MY35_002)by Ente Cassa di Risparmio di Firenzeby FiorGen ONLUS to Galli A
文摘Pancreatic ductal adenocarcinoma (PDAC) is a devastating disease with a median overall survival time of 5 mo and the five years survival less than 5%, a rate essentially unchanged over the course of the years. A well defined progression model of accumulation of genetic alterations ranging from single point mutations to gross chromosomal abnormalities has been introduced to describe the origin of this disease. However, due to the its subtle nature and concurring events PDAC cure remains elusive. Nuclear receptors (NR) are members of a large superfamily of evolutionarily conserved ligand-regulated DNA-binding transcription factors functionally involved in important cellular functions ranging from regulation of metabolism, to growth and development. Given the nature of their ligands, NR are very tempting drug targets and their pharmacological modulation has been widely exploited for the treatment of metabolic and inflammatory diseases. There are now clear evidences that both classical ligand-activated and orphan NR are involved in the pathogenesis of PDAC from its very early stages; nonetheless many aspects of their role are not fully understood. The purpose of this review is to highlight the striking connections that link peroxisome proliferator activated receptors, retinoic acid receptors, retinoid X receptor, androgen receptor, estrogen receptors and the orphan NR Nur, chicken ovalbumin upstream promoter transcription factor II and the liver receptor homologue-1 receptor to PDAC development, connections that could lead to the identification of novel therapies for this disease.
基金supported by the Army Laboratory Animal Foundation of China,No.SYDW[2020]22(to TC)the Shaanxi Provincial Key R&D Plan General Project of China,No.2022SF-236(to YM)the National Natural Science Foundation of China,No.82202070(to TC)。
文摘A microgravity environment has been shown to cause ocular damage and affect visual acuity,but the underlying mechanisms remain unclear.Therefore,we established an animal model of weightlessness via tail suspension to examine the pathological changes and molecular mechanisms of retinal damage under microgravity.After 4 weeks of tail suspension,there were no notable alterations in retinal function and morphology,while after 8 weeks of tail suspension,significant reductions in retinal function were observed,and the outer nuclear layer was thinner,with abundant apoptotic cells.To investigate the mechanism underlying the degenerative changes that occurred in the outer nuclear layer of the retina,proteomics was used to analyze differentially expressed proteins in rat retinas after 8 weeks of tail suspension.The results showed that the expression levels of fibroblast growth factor 2(also known as basic fibroblast growth factor)and glial fibrillary acidic protein,which are closely related to Müller cell activation,were significantly upregulated.In addition,Müller cell regeneration and Müller cell gliosis were observed after 4 and 8 weeks,respectively,of simulated weightlessness.These findings indicate that Müller cells play an important regulatory role in retinal outer nuclear layer degeneration during weightlessness.
