Spinal cord injury is accompanied by a substantial loss of neurons.Cell replacement therapy improves motor and sensory dysfunction by replacing dead neurons,and endogenous neurogenesis is an important cell replacement...Spinal cord injury is accompanied by a substantial loss of neurons.Cell replacement therapy improves motor and sensory dysfunction by replacing dead neurons,and endogenous neurogenesis is an important cell replacement source.Stimulating endogenous neurogenesis is therefore a viable approach for treating spinal cord injury.Given that basic fibroblast growth factor is a potent inducer of neurogenesis,we developed a sustained-release system of basic fibroblast growth factor-chitosan to enhance tissue repair in spinal cord injury.In the present study,we isolated neural stem cells from the spinal cords of neonatal rats and used single-cell RNA sequencing to trace the complete process of neurogenesis under ex vivo culture conditions.Under the influence of basic fibroblast growth factor-chitosan,neural stem cells were able to transition from a quiescent state to an activated state and subsequently differentiate into neuronal precursor cells and immature neurons.Additionally,basic fibroblast growth factor-chitosan significantly enhanced neural stem cell proliferation in vitro and promoted neuronal generation.Subsequent in vivo experiments confirmed the therapeutic efficacy of basic fibroblast growth factor-chitosan in spinal cord injury,demonstrating enhanced neurogenesis and tissue repair.展开更多
The presence of endogenous neural stem/progenitor cells in the adult mammalian brain suggests that the central nervous system can be repaired and regenerated after injury.However,whether it is possible to stimulate ne...The presence of endogenous neural stem/progenitor cells in the adult mammalian brain suggests that the central nervous system can be repaired and regenerated after injury.However,whether it is possible to stimulate neurogenesis and reconstruct cortical layers II to VI in non-neurogenic regions,such as the cortex,remains unknown.In this study,we implanted a hyaluronic acid collagen gel loaded with basic fibroblast growth factor into the motor cortex immediately following traumatic injury.Our findings reveal that this gel effectively stimulated the proliferation and migration of endogenous neural stem/progenitor cells,as well as their differentiation into mature and functionally integrated neurons.Importantly,these new neurons reconstructed the architecture of cortical layers II to VI,integrated into the existing neural circuitry,and ultimately led to improved brain function.These findings offer novel insight into potential clinical treatments for traumatic cerebral cortex injuries.展开更多
Volcanic ashes are posing increasingly severer threats to the aviation safety.As the operation temperature of the turbine engine elevates,molten volcanic ash leads to the degradation of the thermal barrier coatings(TB...Volcanic ashes are posing increasingly severer threats to the aviation safety.As the operation temperature of the turbine engine elevates,molten volcanic ash leads to the degradation of the thermal barrier coatings(TBCs)and eventually catastrophic engine failure.However,the physical and chemical properties of volcanic ashes vary due to the distinct chemical compositions,rendering it extremely challenging to evaluate the effects of each ash material on the failure of TBC.Here,we proposed a new metric termed Basicity to investigate the influence of chemical composition on the melting temperature and viscosity of volcanic ashes.Artificial CaO-MgO-Al_(2)O_(3)-SiO_(2) materials(CMAS)were synthesized to simulate the wetting,spreading and corrosion behavior of volcanic ashes at 1300 ℃ on(Gd_(0.9)Yb_(0.1))2Zr_(2)O_(7)(GYbZ),a model TBC material.Our results reveal that the synthetic CMAS does not fully capture the damage caused by volcanic ash due to the difference in compositions.The viscosity and characteristic temperatures decrease as the Basicity value increases,indicating its significant impact on the fusion properties of ashes.Notably,distinct from CMAS,the unexpected presence of Fe_(2)O_(3) in volcanic ashes promotes the formation of garnet phase,conversely impedes the formation of apatite dense layer.These findings provide valuable insights into the corrosion mechanisms caused by TBC and strategies for TBC protection against volcanic ashes.展开更多
During the continuous casting process of high-Mn high-Al steels,various types of gases such as Ar need to escape through the top of the mold.In which,the behavior of bubbles traversing the liquid slag serves as a rest...During the continuous casting process of high-Mn high-Al steels,various types of gases such as Ar need to escape through the top of the mold.In which,the behavior of bubbles traversing the liquid slag serves as a restrictive link,closely associated with viscosity and the thickness of liquid slag.In contrast to two-dimensional surface observation,three-dimensional(3D)analysis method can offer a more intuitive,accurate,and comprehensive information.Therefore,this study employs a 3D X-ray microscope(3D-XRM)to obtained spatial distribution and 3D morphological characteristics of residual bubbles in mold flux under different basicity of liquid slag,different temperatures,and different holding times.The results indicate that as basicity of slag increases from 0.52 to 1.03,temperature increases from 1423 to 1573 K,the viscosity of slag decreases,the floating rate of bubbles increases.In addition,when holding time increases from 10 to 30 s,the bubbles floating distance increases,and the volume fraction and average equivalent sphere diameter of the bubbles solidified in the mold flux gradually decreases.In one word,increasing the basicity,temperature,and holding time leading to an increase in the removal rate of bubbles especially for the large.These findings of bubbles escape behavior provide valuable insights into optimizing low basicity mold flux for high-Mn high-Al steels.展开更多
AIM:To compare refractive error and angle of deviation in patients with basic esotropia and basic exotropia.METHODS:A retrospective review was conducted on the medical records of patients with basic-type strabismus.De...AIM:To compare refractive error and angle of deviation in patients with basic esotropia and basic exotropia.METHODS:A retrospective review was conducted on the medical records of patients with basic-type strabismus.Demographic data,refractive error,best-corrected distance visual acuity(BCVA),and the horizontal and vertical angle of deviation between basic esotropia and exotropia patients were compared.RESULTS:Among the 7129 patients(mean age 22.98±14.81y)evaluated,44.7%(3185 cases,54.9%male)exhibited basic-type esotropia,while 55.3%(3944 cases,53.9%male)presented with basic-type exotropia.Basic esotropia cases exhibited more hyperopic spherical equivalent measurements in both eyes(right:0.53±3.07 vs left:0.56±2.98 D)than those with basic exotropia(right eye:-0.33±2.84 vs left eye:-0.24±2.68 D,P<0.001 for both eyes).Patients with basic esotropia had significantly greater horizontal deviation angles(near:36.08±18.87 PD and far:35.56±18.75 PD)compared to those with basic exotropia(near:33.75±16.11 PD and far:33.26±15.90 PD,P<0.001).Conversely,patients with basic exotropia had slightly higher vertical deviation angles(near:1.67±5.80 PD and far:1.72±5.89 PD)compared to those with basic esotropia(near:1.12±4.57 PD and far:1.12±4.58 PD,P<0.001).Patients with basic esotropia underwent surgical intervention at younger ages compared to basic exotropia individuals(19.68±15.99 vs 25.66±13.20,P<0.001).CONCLUSION:Basic esotropia patients present more hyperopic refractive errors,better visual acuity,larger horizontal yet smaller vertical ocular misalignments,and tend to undergo strabismus surgery at younger ages relative to basic exotropia cases.展开更多
The beauty in basic education is pure,simple and true.The beautiful works created by teachers,the beautiful works of teaching materials and the statues of model teachers were gathered in the palace of beauty-the Natio...The beauty in basic education is pure,simple and true.The beautiful works created by teachers,the beautiful works of teaching materials and the statues of model teachers were gathered in the palace of beauty-the National Art Museum of China,nourishing the heart of the public with the beauty in basic education.展开更多
The properties of direct reduced iron(DRI)smelting slag are important in the DRI melting process for molten iron production to ensure the slag-iron separation and quality of molten iron.The influence of binary basicit...The properties of direct reduced iron(DRI)smelting slag are important in the DRI melting process for molten iron production to ensure the slag-iron separation and quality of molten iron.The influence of binary basicity on the viscosity and sulfide capacity of CaO-SiO_(2)-MgO-Al_(2)O_(3)-FeO slag was investigated by the high-temperature experiments,structural analysis and thermodynamic calculation.The viscosity of the slag decreased rapidly with an increase in basicity from 0.4 to 0.8,and this trend became slow as the basicity further increased to 1.2.For the acidic slag with basicity of 0.4 and 0.6,the viscosity at 1500℃ was higher than 0.6 Pa s,which was harmful for the fluidity of slag melt.The slags with basicity of 0.8,1.0 and 1.2 at 1500℃ showed the low viscosity of less than 0.6 Pa s.For the basic slag with basicity of 1.0 and 1.2,the rapid precipitation of melilite led to the abrupt increase behavior of the viscosity,and the acidic slag showed the gentle temperature-viscosity curves.The Raman analysis revealed that the conversion from Q^(3) to Q^(2),Q^(1) and Q^(0) mainly occurred with the basicity increasing from 0.4 to 0.8,and the conversion from Q^(2) to Q^(1) and Q^(0) was dominant with further increase in basicity to 1.2,decreasing the degree of polymerization.The sulfide capacity was improved with the increasing basicity due to the increase in O^(2-)ions,and CaS could be formed dominantly for S^(2-)stabilization in present slag.The sulfur partition ratio was derived from sulfide capacity,and the values of sulfur partition ratio at basicity of 0.4 and 0.6 were much smaller than those at basicity of 0.8,1.0 and 1.2,indicating a weak desulfurization ability of the slag with a low basicity.展开更多
基金supported by the National Natural Science Foundation of China,Nos.82271403(to XL),82272171(to ZY),31730030(to XL),81941011(to XL),31971279(to ZY)the Natural Science Foundation of Beijing,No.7222004(to HD).
文摘Spinal cord injury is accompanied by a substantial loss of neurons.Cell replacement therapy improves motor and sensory dysfunction by replacing dead neurons,and endogenous neurogenesis is an important cell replacement source.Stimulating endogenous neurogenesis is therefore a viable approach for treating spinal cord injury.Given that basic fibroblast growth factor is a potent inducer of neurogenesis,we developed a sustained-release system of basic fibroblast growth factor-chitosan to enhance tissue repair in spinal cord injury.In the present study,we isolated neural stem cells from the spinal cords of neonatal rats and used single-cell RNA sequencing to trace the complete process of neurogenesis under ex vivo culture conditions.Under the influence of basic fibroblast growth factor-chitosan,neural stem cells were able to transition from a quiescent state to an activated state and subsequently differentiate into neuronal precursor cells and immature neurons.Additionally,basic fibroblast growth factor-chitosan significantly enhanced neural stem cell proliferation in vitro and promoted neuronal generation.Subsequent in vivo experiments confirmed the therapeutic efficacy of basic fibroblast growth factor-chitosan in spinal cord injury,demonstrating enhanced neurogenesis and tissue repair.
基金supported by the National Natural Science Foundation of China,Nos.82272171(to ZY),82271403(to XL),81941011(to XL),31971279(to ZY),31730030(to XL)the Natural Science Foundation of Beijing,No.7222004(to HD).
文摘The presence of endogenous neural stem/progenitor cells in the adult mammalian brain suggests that the central nervous system can be repaired and regenerated after injury.However,whether it is possible to stimulate neurogenesis and reconstruct cortical layers II to VI in non-neurogenic regions,such as the cortex,remains unknown.In this study,we implanted a hyaluronic acid collagen gel loaded with basic fibroblast growth factor into the motor cortex immediately following traumatic injury.Our findings reveal that this gel effectively stimulated the proliferation and migration of endogenous neural stem/progenitor cells,as well as their differentiation into mature and functionally integrated neurons.Importantly,these new neurons reconstructed the architecture of cortical layers II to VI,integrated into the existing neural circuitry,and ultimately led to improved brain function.These findings offer novel insight into potential clinical treatments for traumatic cerebral cortex injuries.
基金financially supported by the Nature Science Foun-dations of China(NSFC)(Nos.52401071 andU21B2052)China National Postdoctoral Program for Innovative Talents(No.BX20240459).
文摘Volcanic ashes are posing increasingly severer threats to the aviation safety.As the operation temperature of the turbine engine elevates,molten volcanic ash leads to the degradation of the thermal barrier coatings(TBCs)and eventually catastrophic engine failure.However,the physical and chemical properties of volcanic ashes vary due to the distinct chemical compositions,rendering it extremely challenging to evaluate the effects of each ash material on the failure of TBC.Here,we proposed a new metric termed Basicity to investigate the influence of chemical composition on the melting temperature and viscosity of volcanic ashes.Artificial CaO-MgO-Al_(2)O_(3)-SiO_(2) materials(CMAS)were synthesized to simulate the wetting,spreading and corrosion behavior of volcanic ashes at 1300 ℃ on(Gd_(0.9)Yb_(0.1))2Zr_(2)O_(7)(GYbZ),a model TBC material.Our results reveal that the synthetic CMAS does not fully capture the damage caused by volcanic ash due to the difference in compositions.The viscosity and characteristic temperatures decrease as the Basicity value increases,indicating its significant impact on the fusion properties of ashes.Notably,distinct from CMAS,the unexpected presence of Fe_(2)O_(3) in volcanic ashes promotes the formation of garnet phase,conversely impedes the formation of apatite dense layer.These findings provide valuable insights into the corrosion mechanisms caused by TBC and strategies for TBC protection against volcanic ashes.
基金financially supported by the National Natural Science Foundation of China(Nos.52274315 and 52374320)the Fundamental Research Funds for the Central Universities(Nos.FRF-TP-22-011A1 and FRF-DF22-16)。
文摘During the continuous casting process of high-Mn high-Al steels,various types of gases such as Ar need to escape through the top of the mold.In which,the behavior of bubbles traversing the liquid slag serves as a restrictive link,closely associated with viscosity and the thickness of liquid slag.In contrast to two-dimensional surface observation,three-dimensional(3D)analysis method can offer a more intuitive,accurate,and comprehensive information.Therefore,this study employs a 3D X-ray microscope(3D-XRM)to obtained spatial distribution and 3D morphological characteristics of residual bubbles in mold flux under different basicity of liquid slag,different temperatures,and different holding times.The results indicate that as basicity of slag increases from 0.52 to 1.03,temperature increases from 1423 to 1573 K,the viscosity of slag decreases,the floating rate of bubbles increases.In addition,when holding time increases from 10 to 30 s,the bubbles floating distance increases,and the volume fraction and average equivalent sphere diameter of the bubbles solidified in the mold flux gradually decreases.In one word,increasing the basicity,temperature,and holding time leading to an increase in the removal rate of bubbles especially for the large.These findings of bubbles escape behavior provide valuable insights into optimizing low basicity mold flux for high-Mn high-Al steels.
文摘AIM:To compare refractive error and angle of deviation in patients with basic esotropia and basic exotropia.METHODS:A retrospective review was conducted on the medical records of patients with basic-type strabismus.Demographic data,refractive error,best-corrected distance visual acuity(BCVA),and the horizontal and vertical angle of deviation between basic esotropia and exotropia patients were compared.RESULTS:Among the 7129 patients(mean age 22.98±14.81y)evaluated,44.7%(3185 cases,54.9%male)exhibited basic-type esotropia,while 55.3%(3944 cases,53.9%male)presented with basic-type exotropia.Basic esotropia cases exhibited more hyperopic spherical equivalent measurements in both eyes(right:0.53±3.07 vs left:0.56±2.98 D)than those with basic exotropia(right eye:-0.33±2.84 vs left eye:-0.24±2.68 D,P<0.001 for both eyes).Patients with basic esotropia had significantly greater horizontal deviation angles(near:36.08±18.87 PD and far:35.56±18.75 PD)compared to those with basic exotropia(near:33.75±16.11 PD and far:33.26±15.90 PD,P<0.001).Conversely,patients with basic exotropia had slightly higher vertical deviation angles(near:1.67±5.80 PD and far:1.72±5.89 PD)compared to those with basic esotropia(near:1.12±4.57 PD and far:1.12±4.58 PD,P<0.001).Patients with basic esotropia underwent surgical intervention at younger ages compared to basic exotropia individuals(19.68±15.99 vs 25.66±13.20,P<0.001).CONCLUSION:Basic esotropia patients present more hyperopic refractive errors,better visual acuity,larger horizontal yet smaller vertical ocular misalignments,and tend to undergo strabismus surgery at younger ages relative to basic exotropia cases.
文摘The beauty in basic education is pure,simple and true.The beautiful works created by teachers,the beautiful works of teaching materials and the statues of model teachers were gathered in the palace of beauty-the National Art Museum of China,nourishing the heart of the public with the beauty in basic education.
基金the financial support from China Postdoctoral Science Foundation(2024M750177)National Natural Science Foundation of China(52474345)and Science and Technology Major Project of WuHan(2023020302020572).
文摘The properties of direct reduced iron(DRI)smelting slag are important in the DRI melting process for molten iron production to ensure the slag-iron separation and quality of molten iron.The influence of binary basicity on the viscosity and sulfide capacity of CaO-SiO_(2)-MgO-Al_(2)O_(3)-FeO slag was investigated by the high-temperature experiments,structural analysis and thermodynamic calculation.The viscosity of the slag decreased rapidly with an increase in basicity from 0.4 to 0.8,and this trend became slow as the basicity further increased to 1.2.For the acidic slag with basicity of 0.4 and 0.6,the viscosity at 1500℃ was higher than 0.6 Pa s,which was harmful for the fluidity of slag melt.The slags with basicity of 0.8,1.0 and 1.2 at 1500℃ showed the low viscosity of less than 0.6 Pa s.For the basic slag with basicity of 1.0 and 1.2,the rapid precipitation of melilite led to the abrupt increase behavior of the viscosity,and the acidic slag showed the gentle temperature-viscosity curves.The Raman analysis revealed that the conversion from Q^(3) to Q^(2),Q^(1) and Q^(0) mainly occurred with the basicity increasing from 0.4 to 0.8,and the conversion from Q^(2) to Q^(1) and Q^(0) was dominant with further increase in basicity to 1.2,decreasing the degree of polymerization.The sulfide capacity was improved with the increasing basicity due to the increase in O^(2-)ions,and CaS could be formed dominantly for S^(2-)stabilization in present slag.The sulfur partition ratio was derived from sulfide capacity,and the values of sulfur partition ratio at basicity of 0.4 and 0.6 were much smaller than those at basicity of 0.8,1.0 and 1.2,indicating a weak desulfurization ability of the slag with a low basicity.
