First mirror(FM)cleaning,using radio frequency(RF)plasma,has been proposed to recover FM reflectivity in nuclear fusion reactors such as the International Thermonuclear Experimental Reactor(ITER).To investigate the in...First mirror(FM)cleaning,using radio frequency(RF)plasma,has been proposed to recover FM reflectivity in nuclear fusion reactors such as the International Thermonuclear Experimental Reactor(ITER).To investigate the influence of simultaneous cleaning of two mirrors on mirror cleaning efficiency and uniformity,experiments involving single-mirror cleaning and dual-mirror cleaning were conducted using RF capacitively coupled plasma in the laboratory.For the test and simultaneous cleaning of two mirrors,the FM and second mirror(SM),both measuring 110 mm×80 mm,were placed inside the first mirror unit(FMU).They were composed of 16 mirror samples,each with a dimension of 27.5 mm×20 mm.These mirror samples consist of a titanium-zirconium-molybdenum alloy substrate,a 500 nm Mo intermediate layer and a 30 nm Al_(2)O_(3) surface coating as a proxy for Be impurities.The cleaning of a single first mirror(SFM)and the simultaneous cleaning of the FM and SM(DFM and DSM)lasted for 9 h using Ar plasma at a pressure of 1 Pa.The total reflectivity of mirror samples on the DSM did not fully recover and varied with location,with a self-bias of−140 V.With a self-bias of−300 V,the total reflectivity of mirror samples on the SFM and DFM was fully recovered.The energy dispersive spectrometer results demonstrated that the Al_(2)O_(3) coating had been completely removed from these mirror samples.However,the mass loss of each mirror sample on the SFM and DFM before and after cleaning varied depending on its location,with higher mass loss observed for mirror samples located in the corners and lower loss for those in the center.Compared with SM cleaning,the simultaneous cleaning of two mirrors reduced the difference between the highest and lowest mass loss.Furthermore,this mass loss for the mirror samples of the DFM facing the DSM was increased.This indicated that mirror samples cleaned face to face in the FMU simultaneously could influence each other,highlighting the need for special attention in future studies.展开更多
Background:Hypertrophy of the ligamentumflavum(HLF)is a common contributor to spinal stenosis which results in significant neurological impairments.Circular RNA(circRNA)circ_0003609 has been linked to HLF;however,the ex...Background:Hypertrophy of the ligamentumflavum(HLF)is a common contributor to spinal stenosis which results in significant neurological impairments.Circular RNA(circRNA)circ_0003609 has been linked to HLF;however,the exact mechanism by which it causes this disease is unclear.Methods:Circ_0003609 expressions were regulated in HLF cells by overexpression vectors and RNA interference.Cell proliferation andfibrosis-related gene expression were checked by the Cell Counting Kit-8(CCK-8)assay and western blotting.CircBank’s prediction of the association between miR-155 and circ_0003609 was supported by a dual-luciferase reporter experiment.The function of the miR-155/sirtuin 1(SIRT1)axis in controlling HLFfibrosis was further examined.Results:Overexpression of circ_0003609 suppressed HLF cell propagation andfibrosis compared to its silencing.It was found that circ_0003609 served as the sponge for miR-155 and that the circ_0003609/miR-155 axis controlled thefibrosis of HLF cells.It was found that circ_0003609 acted as a sponge for miR-155,regulating thefibrosis of HLF cells.Further,miR-155 targets SIRT1,and the miR-155/SIRT1 axis promotes HLF cellfibrosis.Conclusion:Circ_0003609 ameliorates hypertrophied ligamentumflavum(LF)by modulating the miR-155/SIRT1 axis,indicating a potential treatment approach for HLF.展开更多
In the Experimental Advanced Superconducting Tokamak(EAST),the reflectivity of the charge exchange recombination spectroscopy(CXRS)first mirror(FM)was dramatically dropped down to 20%of the original value after the op...In the Experimental Advanced Superconducting Tokamak(EAST),the reflectivity of the charge exchange recombination spectroscopy(CXRS)first mirror(FM)was dramatically dropped down to 20%of the original value after the operation of two EAST experimental campaigns from 2014-2015,leading to degradation of the signal intensity of the CXRS diagnostic to an unacceptably low level.The radio frequency(RF)plasma cleaning of the CXRS FM with a dimension of 303×81×76 mm3 and a small curvature of 0.008 mm-1 was performed to remove deposits to recover the reflectivity.After 168 h cleaning by RF plasma,the maximum specular reflectivity of the FM could reach 92%of the original value at 532 nm,making the cleaned CXRS FM eligible to be reused for the CXRS diagnostic in the 2016 EAST campaign.Dedicated tests of sputtering polished mirror samples were performed to explore the cleaning uniformity and possible damage to the mirror surface.The specular reflectivity did not show obvious dependence on locations along the surface with the same cleaning time.The measured surface roughness gradually increased with sputtering time.The reflectivity remained almost unchanged regardless of different sputtering times and locations,indicating negligible damage to the FM surface even after 100 h sputtering.The recontaminated CXRS FM in the 2016 EAST campaign was firstly cleaned for 81 h,and the least reflectivity recovery for areas with relatively thick deposits was only 40%.After continuing cleaning to 147 h,redeposition of the sputtered residual deposits on the FM surface was observed.In the future for in situ cleaning of the FMs in EAST and ITER,deposits should be removed timely when they are very thin taking into account a very long cleaning time and presumable redeposition of thick and nonuniform deposits.展开更多
Dust presented in experimental advanced superconducting tokamak(EAST)with mixed plasmafacing materials has been collected and characterized for the first time.Dust at different positions in the vessel was collected by...Dust presented in experimental advanced superconducting tokamak(EAST)with mixed plasmafacing materials has been collected and characterized for the first time.Dust at different positions in the vessel was collected by vacuum cleaner after the first experimental campaign in 2019.The shape,composition,and size of dust particles have been analyzed using different methods.About 80%of the total number of dust particles have size between 20 and 80μm,and most of dust particles are spherical,while schistose shape,columnar and irregular shape were also found.With the help of energy-dispersive x-ray spectroscopy different elements of dust have been identified,which is generally consistent with the different plasma-facing components in EAST.Both x-ray fluorescence and inductively coupled plasma emission spectrometer are complementary methods for measuring the dust composition quantitatively.It was found that the major components of dust were lithium dust in the form of lithium carbonate and lithium hydroxide,which is due to the routine lithium wall conditioning during EAST operation.展开更多
Tungsten monoblock type tiles with ITER dimensions along with supporting cassette components were installed at EAST's upper diverter during 2014 and EAST's lower diverter will also be upgraded in the future. These c...Tungsten monoblock type tiles with ITER dimensions along with supporting cassette components were installed at EAST's upper diverter during 2014 and EAST's lower diverter will also be upgraded in the future. These cassette structures pose critical issues on the high cumulative incident heat flux due to the leading edges and misalignments (0 ~ 1.5 mm), which may result in the destruction or even melting of the tungsten tile. The present work summarizes the thermal analysis using ANSYS multiphysics software 15.0 performed on the actively cooled W tiles to evaluate the shaping effect on surface temperature. In the current heat flux conditions (Q11 ~ 100 MW m-2), the adopted chamfer shaping (1 ×1 mm) can only reduce the maximum temperature by about 14%, but it also has a melting risk at the maximum misalignment of 1.5 mm. The candidate shaping solutions elliptical (round) edge, dome and fish-scale are analyzed for comparison and are identified not as good as the dual chamfer structure. A relatively good dual chamfer (2 ×13 mm) shaping forming a symmetrical sloping roof structure can effectively counteract the 1.5 mm misalignment, reducing the maximum temperature by up to 50%. However, in the future heat flux conditions (Q11 ~287 MW m-2), it may only endure about 0.5 mm misalignment. Moreover, no proper shaping solution has been found that can avoid melting at the maximum misalignment of 1.5 mm. Thus, the engineering misalignment has to be limited to an acceptable level.展开更多
Carbohydrates on cell surfaces play a crucial role in a wide variety of biological processes,including cell adhesion,recognition and signaling,viral and bacterial infection,in°ammation and metastasis.However,owin...Carbohydrates on cell surfaces play a crucial role in a wide variety of biological processes,including cell adhesion,recognition and signaling,viral and bacterial infection,in°ammation and metastasis.However,owing to the large diversity and complexity of carbohydrate structure and nongenetically synthesis,glycoscience is the least understood¯eld compared with genomics and proteomics.Although the structures and functions of carbohydrates have been investigated by various conventional analysis methods,the distribution and role of carbohydrates in cell membranes remain elusive.This review focuses on the developments and challenges of super-resolution imaging in glycoscience through introduction of imaging principle and the available°uorescent probes for super-resolution imaging,the labeling strategies of carbohydrates,and the recent applications of super-resolution imaging in glycoscience,which will promote the super-resolution imaging technology as a promising tool to provide new insights into the study of glycoscience.展开更多
First mirrors(FMs) are crucial components of optical diagnostic systems in present-day tokamaks and future fusion reactors. Their lifetimes should be extremely limited due to their proximity to burning plasma, great...First mirrors(FMs) are crucial components of optical diagnostic systems in present-day tokamaks and future fusion reactors. Their lifetimes should be extremely limited due to their proximity to burning plasma, greatly influencing the safe operation of corresponding diagnostics.Repetitive cleaning is expected to provide a solution to the frequent replacement of contaminated FMs, thus prolonging their lifetimes. Three repetitive cleaning cycles using radio frequency plasma were applied to stainless steel(SS) FM samples, to evaluate the change of the mirrors' optical properties and morphology during each cycle. Amorphous carbon films were deposited on mirror surfaces under identical conditions in three cycles. In three cycles with identical cleaning parameters, the total reflectivity was restored at up to 95%. Nevertheless, with successive cleaning cycles, the FM surfaces gradually appeared to roughen due to damage to the grain boundaries. Correspondingly, the diffuse reflectivity increased from a few percent to 20%and 27% after the second and third cycles. After optimizing the cleaning parameters of the second and third cycles, the roughness showed a significant decrease, and simultaneously the increase of diffuse reflectivity was remarkably improved.展开更多
Advanced fluorescence microscopy including single-molecule localization-based super-resolution imaging techniques requires bright and photostable dyes orproteins asfluorophores.The photophysical properties of fluoroph...Advanced fluorescence microscopy including single-molecule localization-based super-resolution imaging techniques requires bright and photostable dyes orproteins asfluorophores.The photophysical properties of fluorophores have been proven to be crucial for super-resolution microscopy's localization precision and imaging resolution.Fluorophores TAMRA and Atto Rho6 G,which can interact with macrocyclic host cucurbit[7]uril(CB7) to form host-guest compounds,were found to improve the fluorescence intensity and lifetimes of these dyes.We enhanced the localization precision of direct stochastic optical reconstruction microscopy(dSTORM) by introducing CB7 into the imaging buffer,and showed that the number of photons as well as localizations of both TAMRA and Atto Rho6 G increase over 2 times.展开更多
Dear Editor,Amyotrophic lateral sclerosis(ALS)is a progressive and fatal neurodegenerative disease that prominently affects both upper and lower motor neurons.The prevalence of ALS has been estimated at 2.6-3.0 per 10...Dear Editor,Amyotrophic lateral sclerosis(ALS)is a progressive and fatal neurodegenerative disease that prominently affects both upper and lower motor neurons.The prevalence of ALS has been estimated at 2.6-3.0 per 100,000 in Europe,5.2 per 100,000 in the USA,and 1.9-9.9 per 100,000 in Asia[1-3].ALS is classified as sporadic(sALS)or familial(fALS),but only 5%-10% of cases are identified as familial[4,5].展开更多
基金supported by the National Key R&D Project of China(No.2022YFE03030000)National Natural Science Foundation of China(Nos.11975269,12275306 and 12075279)+3 种基金the Youth Innovation Promotion Association of the Chinese Academy of Sciences(No.2022452)the Anhui Provincial Natural Science Foundation(No.2208085J40)the CASHIPS Director’s Fund(Nos.YZJJQY202302 and BJPY2023B03)the Comprehensive Research Facility for Fusion Technology Program of China(No.2018-000052-73-01-001228).
文摘First mirror(FM)cleaning,using radio frequency(RF)plasma,has been proposed to recover FM reflectivity in nuclear fusion reactors such as the International Thermonuclear Experimental Reactor(ITER).To investigate the influence of simultaneous cleaning of two mirrors on mirror cleaning efficiency and uniformity,experiments involving single-mirror cleaning and dual-mirror cleaning were conducted using RF capacitively coupled plasma in the laboratory.For the test and simultaneous cleaning of two mirrors,the FM and second mirror(SM),both measuring 110 mm×80 mm,were placed inside the first mirror unit(FMU).They were composed of 16 mirror samples,each with a dimension of 27.5 mm×20 mm.These mirror samples consist of a titanium-zirconium-molybdenum alloy substrate,a 500 nm Mo intermediate layer and a 30 nm Al_(2)O_(3) surface coating as a proxy for Be impurities.The cleaning of a single first mirror(SFM)and the simultaneous cleaning of the FM and SM(DFM and DSM)lasted for 9 h using Ar plasma at a pressure of 1 Pa.The total reflectivity of mirror samples on the DSM did not fully recover and varied with location,with a self-bias of−140 V.With a self-bias of−300 V,the total reflectivity of mirror samples on the SFM and DFM was fully recovered.The energy dispersive spectrometer results demonstrated that the Al_(2)O_(3) coating had been completely removed from these mirror samples.However,the mass loss of each mirror sample on the SFM and DFM before and after cleaning varied depending on its location,with higher mass loss observed for mirror samples located in the corners and lower loss for those in the center.Compared with SM cleaning,the simultaneous cleaning of two mirrors reduced the difference between the highest and lowest mass loss.Furthermore,this mass loss for the mirror samples of the DFM facing the DSM was increased.This indicated that mirror samples cleaned face to face in the FMU simultaneously could influence each other,highlighting the need for special attention in future studies.
基金This research was supported by the Shanghai Natural Science Fund(No.21ZR1447500)Shanghai Jiao Tong University School of Medicine Affiliated Renji Hospital Baoshan Branch Medical Key Specialty Construction Project(No.rbzdzk-2023-001).
文摘Background:Hypertrophy of the ligamentumflavum(HLF)is a common contributor to spinal stenosis which results in significant neurological impairments.Circular RNA(circRNA)circ_0003609 has been linked to HLF;however,the exact mechanism by which it causes this disease is unclear.Methods:Circ_0003609 expressions were regulated in HLF cells by overexpression vectors and RNA interference.Cell proliferation andfibrosis-related gene expression were checked by the Cell Counting Kit-8(CCK-8)assay and western blotting.CircBank’s prediction of the association between miR-155 and circ_0003609 was supported by a dual-luciferase reporter experiment.The function of the miR-155/sirtuin 1(SIRT1)axis in controlling HLFfibrosis was further examined.Results:Overexpression of circ_0003609 suppressed HLF cell propagation andfibrosis compared to its silencing.It was found that circ_0003609 served as the sponge for miR-155 and that the circ_0003609/miR-155 axis controlled thefibrosis of HLF cells.It was found that circ_0003609 acted as a sponge for miR-155,regulating thefibrosis of HLF cells.Further,miR-155 targets SIRT1,and the miR-155/SIRT1 axis promotes HLF cellfibrosis.Conclusion:Circ_0003609 ameliorates hypertrophied ligamentumflavum(LF)by modulating the miR-155/SIRT1 axis,indicating a potential treatment approach for HLF.
基金National Natural Science Foundation of China(Nos.11975269,11905252,11675218,11675219,11775260,11861131010,11875230)the National Key R&D Program of China(Nos.2017YFA0402500 and 2017YFE0301300)。
文摘In the Experimental Advanced Superconducting Tokamak(EAST),the reflectivity of the charge exchange recombination spectroscopy(CXRS)first mirror(FM)was dramatically dropped down to 20%of the original value after the operation of two EAST experimental campaigns from 2014-2015,leading to degradation of the signal intensity of the CXRS diagnostic to an unacceptably low level.The radio frequency(RF)plasma cleaning of the CXRS FM with a dimension of 303×81×76 mm3 and a small curvature of 0.008 mm-1 was performed to remove deposits to recover the reflectivity.After 168 h cleaning by RF plasma,the maximum specular reflectivity of the FM could reach 92%of the original value at 532 nm,making the cleaned CXRS FM eligible to be reused for the CXRS diagnostic in the 2016 EAST campaign.Dedicated tests of sputtering polished mirror samples were performed to explore the cleaning uniformity and possible damage to the mirror surface.The specular reflectivity did not show obvious dependence on locations along the surface with the same cleaning time.The measured surface roughness gradually increased with sputtering time.The reflectivity remained almost unchanged regardless of different sputtering times and locations,indicating negligible damage to the FM surface even after 100 h sputtering.The recontaminated CXRS FM in the 2016 EAST campaign was firstly cleaned for 81 h,and the least reflectivity recovery for areas with relatively thick deposits was only 40%.After continuing cleaning to 147 h,redeposition of the sputtered residual deposits on the FM surface was observed.In the future for in situ cleaning of the FMs in EAST and ITER,deposits should be removed timely when they are very thin taking into account a very long cleaning time and presumable redeposition of thick and nonuniform deposits.
基金supported by National Natural Science Foundation of China(Nos.12022511,11861131010 and 12075279)the National Key Research and Development Program of China(Nos.2017YFE0301300 and 2017YFA0402500)+1 种基金the CASHIPS Director’s Fund(No.BJPY2019B01)the Key Research Program of Frontier Sciences of CAS(No.ZDBS-LY-SLH010).
文摘Dust presented in experimental advanced superconducting tokamak(EAST)with mixed plasmafacing materials has been collected and characterized for the first time.Dust at different positions in the vessel was collected by vacuum cleaner after the first experimental campaign in 2019.The shape,composition,and size of dust particles have been analyzed using different methods.About 80%of the total number of dust particles have size between 20 and 80μm,and most of dust particles are spherical,while schistose shape,columnar and irregular shape were also found.With the help of energy-dispersive x-ray spectroscopy different elements of dust have been identified,which is generally consistent with the different plasma-facing components in EAST.Both x-ray fluorescence and inductively coupled plasma emission spectrometer are complementary methods for measuring the dust composition quantitatively.It was found that the major components of dust were lithium dust in the form of lithium carbonate and lithium hydroxide,which is due to the routine lithium wall conditioning during EAST operation.
基金Supported by the National Magnetic Confinement Fusion Science Program of China(Nos.2013GB107004 and 2013GB105003)National Natural Science Foundation of China(No.11405209)
文摘Tungsten monoblock type tiles with ITER dimensions along with supporting cassette components were installed at EAST's upper diverter during 2014 and EAST's lower diverter will also be upgraded in the future. These cassette structures pose critical issues on the high cumulative incident heat flux due to the leading edges and misalignments (0 ~ 1.5 mm), which may result in the destruction or even melting of the tungsten tile. The present work summarizes the thermal analysis using ANSYS multiphysics software 15.0 performed on the actively cooled W tiles to evaluate the shaping effect on surface temperature. In the current heat flux conditions (Q11 ~ 100 MW m-2), the adopted chamfer shaping (1 ×1 mm) can only reduce the maximum temperature by about 14%, but it also has a melting risk at the maximum misalignment of 1.5 mm. The candidate shaping solutions elliptical (round) edge, dome and fish-scale are analyzed for comparison and are identified not as good as the dual chamfer structure. A relatively good dual chamfer (2 ×13 mm) shaping forming a symmetrical sloping roof structure can effectively counteract the 1.5 mm misalignment, reducing the maximum temperature by up to 50%. However, in the future heat flux conditions (Q11 ~287 MW m-2), it may only endure about 0.5 mm misalignment. Moreover, no proper shaping solution has been found that can avoid melting at the maximum misalignment of 1.5 mm. Thus, the engineering misalignment has to be limited to an acceptable level.
基金This work was supported by NSFC (Grants 31330082,21373200,21525314)the Instrument Developing project of the Chinese Academy of Sciences (Grant YZ201455).
文摘Carbohydrates on cell surfaces play a crucial role in a wide variety of biological processes,including cell adhesion,recognition and signaling,viral and bacterial infection,in°ammation and metastasis.However,owing to the large diversity and complexity of carbohydrate structure and nongenetically synthesis,glycoscience is the least understood¯eld compared with genomics and proteomics.Although the structures and functions of carbohydrates have been investigated by various conventional analysis methods,the distribution and role of carbohydrates in cell membranes remain elusive.This review focuses on the developments and challenges of super-resolution imaging in glycoscience through introduction of imaging principle and the available°uorescent probes for super-resolution imaging,the labeling strategies of carbohydrates,and the recent applications of super-resolution imaging in glycoscience,which will promote the super-resolution imaging technology as a promising tool to provide new insights into the study of glycoscience.
基金supported by National Magnetic Confinement Fusion Science Program of China under Contract Nos. 2013GB105003 and 2013GB107004National Natural Science Foundation of China under Contract Nos. 11475218, 11505231, 11375010 and 11675218
文摘First mirrors(FMs) are crucial components of optical diagnostic systems in present-day tokamaks and future fusion reactors. Their lifetimes should be extremely limited due to their proximity to burning plasma, greatly influencing the safe operation of corresponding diagnostics.Repetitive cleaning is expected to provide a solution to the frequent replacement of contaminated FMs, thus prolonging their lifetimes. Three repetitive cleaning cycles using radio frequency plasma were applied to stainless steel(SS) FM samples, to evaluate the change of the mirrors' optical properties and morphology during each cycle. Amorphous carbon films were deposited on mirror surfaces under identical conditions in three cycles. In three cycles with identical cleaning parameters, the total reflectivity was restored at up to 95%. Nevertheless, with successive cleaning cycles, the FM surfaces gradually appeared to roughen due to damage to the grain boundaries. Correspondingly, the diffuse reflectivity increased from a few percent to 20%and 27% after the second and third cycles. After optimizing the cleaning parameters of the second and third cycles, the roughness showed a significant decrease, and simultaneously the increase of diffuse reflectivity was remarkably improved.
基金supported by the National Natural Science Foundation of China(31330082,21373200,21525314)the Instrument Developing Project of the Chinese Academy of Sciences(YZ201455)
文摘Advanced fluorescence microscopy including single-molecule localization-based super-resolution imaging techniques requires bright and photostable dyes orproteins asfluorophores.The photophysical properties of fluorophores have been proven to be crucial for super-resolution microscopy's localization precision and imaging resolution.Fluorophores TAMRA and Atto Rho6 G,which can interact with macrocyclic host cucurbit[7]uril(CB7) to form host-guest compounds,were found to improve the fluorescence intensity and lifetimes of these dyes.We enhanced the localization precision of direct stochastic optical reconstruction microscopy(dSTORM) by introducing CB7 into the imaging buffer,and showed that the number of photons as well as localizations of both TAMRA and Atto Rho6 G increase over 2 times.
基金supported by the Key Program of the Natural Science Foundation of Guangdong Province,China(2017B030311015)Guangzhou Municipal People’s Livelihood Science and Technology Project(201803010085)the National Key R&D Program of China(2017YFC1310200).
文摘Dear Editor,Amyotrophic lateral sclerosis(ALS)is a progressive and fatal neurodegenerative disease that prominently affects both upper and lower motor neurons.The prevalence of ALS has been estimated at 2.6-3.0 per 100,000 in Europe,5.2 per 100,000 in the USA,and 1.9-9.9 per 100,000 in Asia[1-3].ALS is classified as sporadic(sALS)or familial(fALS),but only 5%-10% of cases are identified as familial[4,5].