It is known that eddy current effect has a great influence on magnetic flux leakage testing(MFL).Usually,contacttype encoder wheels are used to measure MFL testing speed to evaluate the effect and further compensate t...It is known that eddy current effect has a great influence on magnetic flux leakage testing(MFL).Usually,contacttype encoder wheels are used to measure MFL testing speed to evaluate the effect and further compensate testing signals.This speed measurement method is complicated,and inevitable abrasion and occasional slippage will reduce the measurement accuracy.In order to solve this problem,based on eddy current effect due to the relative movement,a speed measurement method is proposed,which is contactless and simple.In the high-speed MFL testing,eddy current induced in the specimen will cause an obvious modification to the applied field.This modified field,which is measured by Hall sensor,can be utilized to reflect the moving speed.Firstly,the measurement principle is illustrated based on Faraday’s law.Then,dynamic finite element simulations are conducted to investigate the modified magnetic field distribution.Finally,laboratory experiments are performed to validate the feasibility of the proposed method.The results show that Bmz(r1)and Bmx(r2)have a linear relation with moving speed,which could be used as an alternative measurement parameter.展开更多
This research mainly describes the generation and diagnosis of plasma using a wire-plate discharge device driven by different power supplies,aimed at investigating the effect of driving source parameters on micro-disc...This research mainly describes the generation and diagnosis of plasma using a wire-plate discharge device driven by different power supplies,aimed at investigating the effect of driving source parameters on micro-discharge induced by a corona.The influence of parameters such as waveform,duty ratio and bias voltage on discharge characteristics was explored preliminarily.Experiment results show that the determination of volt-ampere characteristics under different driving source waveforms indicates that the application of square and pulse waveforms shows great advantages over that of sawtooth and sinusoidal waveforms.Similarly,the photo-thermal effects of the system were investigated by comparing the high-voltage electrode temperature and relative emission intensity of N2(C^3Πu—>B^Πg,0-0,337 nm),where square and pulse waveforms also achieved better performance.But the pulse waveform had a slight advantage over the square waveform in terms of energy conversion.Further,investigations of the duty ratio and bias voltage applied on the pulse waveform were conducted,and the results indicate that the duty ratio could effectively improve the discharge power and thermal effect to a certain extent;however,the application of bias voltage on the pulse signal had little influence on the discharge power and thermal effect.展开更多
Our previous study has showed that restraint stress inhibits T cell proliferation. Kv1.3 plays a key role in the lymphocyte activation process. Here, we investigate the effects of restraint stress on murine splenic T ...Our previous study has showed that restraint stress inhibits T cell proliferation. Kv1.3 plays a key role in the lymphocyte activation process. Here, we investigate the effects of restraint stress on murine splenic T and B cell proliferation and the role of Kv1.3 in the process. 3H-TdR incorporation is used to determine changes in splenocyte proliferation stimulated by Con A or LPS between control and restraint stress groups. The data shows that restraint stress inhibits T cell and enhanced B cell proliferation. Data from RT-PCR and Western blotting shows that Kv1.3 gene and protein levels are downregulated in T cells and upregulated in B cells in stressed mice. To examine a possible cause-and-effect relationship between Kv1.3 and stress-affected lymphocyte proliferation, we employ various Kv1.3 specific blockers (quinine, 4-AP and TEA) to determine K+ channel function under restraint stress. The data shows that Kv1.3 blockers reverse the decreased T cell proliferation and increase B cell proliferation induced by restraint stress. These results indicate that Kv1.3 mediates restraint stress-induced modulation of T/B lymphocyte proliferation.展开更多
Hibernation is an adaptive behavior for some small animals to survive cold winter.Hibernating mammals usually down-regulate their body temperature from~37℃to only a few degrees.During the evolution,mammalian hibernat...Hibernation is an adaptive behavior for some small animals to survive cold winter.Hibernating mammals usually down-regulate their body temperature from~37℃to only a few degrees.During the evolution,mammalian hibernators have inherited unique strategies to survive extreme conditions that may lead to disease or death in humans and other non-hibernators.Hibernating mammals can not only tolerant deep hypothermia,hypoxia and anoxia,but also protect them against osteoporosis,muscle atrophy,heart arrhythmia and ischemia-reperfusion injury.Finding the molecular and regulatory mechanisms underlying these adaptations will provide novel ideas for treating related human diseases.展开更多
Radioisotope leaking from nuclear waste has become an intractable problem due to its gamma radiation and strong water solubility.In this work,a novel porous ZnFC-PA/PSF composite sphere was fabricated by immobilizatio...Radioisotope leaking from nuclear waste has become an intractable problem due to its gamma radiation and strong water solubility.In this work,a novel porous ZnFC-PA/PSF composite sphere was fabricated by immobilization of ferrocyanides modified zinc phytate into polysulfone(PSF)substrate for the treatment of Cs-contaminated water.The maximum adsorption capacity of ZnFC-PA/PSF was 305.38 mg/g,and the removal efficiency of Cs+was reached 94.27%within 2 hr.The ZnFC-PA/PSF presented favorable stability with negligible dissolution loss of Zn^(2+)and Fe^(2+)(<2%).The ZnFC-PA/PSF achieved high-selectivity towards Cs+(K_(d)=2.24×10^(4)mL/g)even in actual geothermal water.The adsorption mechanism was inferred to be the ion-exchange between Cs^(+)and K^(+).What’s more,ZnFC-PA/PSF worked well in the fixed-bed adsorption(E=91.92%),indicating the application potential for the hazardous Cs^(+)removal from wastewater.展开更多
Mammals exhibit limited heart regeneration ability,which can lead to heart failure after myocardial infarction.In contrast,zebrafish exhibit remarkable cardiac regeneration capacity.Several cell types and signaling pa...Mammals exhibit limited heart regeneration ability,which can lead to heart failure after myocardial infarction.In contrast,zebrafish exhibit remarkable cardiac regeneration capacity.Several cell types and signaling pathways have been reported to participate in this process.However,a comprehensive analysis of how different cells and signals interact and coordinate to regulate cardiac regeneration is unavailable.We collected major cardiac cell types from zebrafish and performed high-precision single-cell transcriptome analyses during both development and post-injury regeneration.We revealed the cellular heterogeneity as well as the molecular progress of cardiomyocytes during these processes,and identified a subtype of atrial cardiomyocyte exhibiting a stem-like state which may transdifferentiate into ventricular cardiomyocytes during regeneration.Furthermore,we identified a regeneration-induced cell(RIC)population in the epicardium-derived cells(EPDC),and demonstrated Angiopoietin 4(Angpt4)as a specific regulator of heart regeneration.angpt4 expression is specifically and transiently activated in RIC,which initiates a signaling cascade from EPDC to endocardium through the Tie2-MAPK pathway,and further induces activation of cathepsin K in cardiomyocytes through RA signaling.Loss of angpt4 leads to defects in scar tissue resolution and cardiomyocyte proliferation,while overexpression of angpt4 accelerates regeneration.Furthermore,we found that ANGPT4 could enhance proliferation of neonatal rat cardiomyocytes,and promote cardiac repair in mice after myocardial infarction,indicating that the function of Angpt4 is conserved in mammals.Our study provides a mechanistic understanding of heart regeneration at single-cell precision,identifies Angpt4 as a key regulator of cardiomyocyte proliferation and regeneration,and offers a novel therapeutic target for improved recovery after human heart injuries.展开更多
控制感是人类的根本需要,相信世界稳定有序、"善有善报、恶有恶报"的正义动机可以帮助我们获得控制感.正义动机是一个内隐加工过程,指向他人遭遇(而非自身遭遇)或社会整体的正义动机是人类根深蒂固的价值判断和社会态度,但由...控制感是人类的根本需要,相信世界稳定有序、"善有善报、恶有恶报"的正义动机可以帮助我们获得控制感.正义动机是一个内隐加工过程,指向他人遭遇(而非自身遭遇)或社会整体的正义动机是人类根深蒂固的价值判断和社会态度,但由于受传统方法社会赞许效应和样本偏差影响,如何在内隐层面准确测量和验证正义动机的他人凸显效应一直是正义研究的难题.因此,本研究采用词嵌入联想测验(word embedding association test)的词、句向量指标,检验正义动机在内隐水平上的他人凸显效应.微博语料库的词向量分析表明,"他人"-"正义"的余弦相似度(语义关联度)显著大于"自我"-"正义"余弦相似度;谷歌BERT模型的句向量分析也重复了上述结果.总之,基于机器学习的词嵌入联想测验证明了内隐正义动机的他人凸显效应,即人们在潜意识里相信他人(而非自己)遭遇或社会整体是个简单美好的正义世界.这提示我们,看似无序的网络世界却蕴含民众对社会秩序的强烈需要,而词嵌入联想测验也为无结构文本背后的社会态度测量提供了新的算法.展开更多
Based on block copolymer assisted topochemical polymerization,a new strategy for facilely producing robust nanoporous membranes with controlled incorporation of functional groups onto nanopores is developed.As exempli...Based on block copolymer assisted topochemical polymerization,a new strategy for facilely producing robust nanoporous membranes with controlled incorporation of functional groups onto nanopores is developed.As exemplified by preparing nanoporous polypyrrole decorated with amino acids,this strategy exhibits a high degree of freedom for tailoring the surface functionality in the created pores.展开更多
Creating hotspots with significantly enhanced electromagnetic(EF) field, efficiently placing target molecules in hotspot region, and achieving uniform and reproducible Raman signals are three critical issues for devel...Creating hotspots with significantly enhanced electromagnetic(EF) field, efficiently placing target molecules in hotspot region, and achieving uniform and reproducible Raman signals are three critical issues for developing high-performance SERS substrates. In this work, large area gold nanoparticle cluster pillar array with a gold mirror at bottom was facilely fabricated by combined use of nanosphere lithography and self-assembly approach. It is both theoretically and experimentally found that through multiple coupling interactions, the electromagnetic fields at interparticle gaps within the gold clusters were significantly enhanced in our three-dimentional(3D) pillar array substrates, which can result in one order of magnitude stronger as compared with random gold clusters on a two-dimentional planar case.Due to the periodic stucture, our substrates also possess the capbility of producing highly uniform and reproducible SERS signals. Attractively, in our case, a photoresponsive polymer was used for the formation of pillar array structure. Its unique photoinduced deformation makes it possible to reversibly open and close the gaps of the closely packed Au NP array, thus enabling efficient placement or entrapment of probe molecules into hotspot sites between adjacent nanoparticles.展开更多
Zangnan Salt Lake on the south of the Tibet is a type of carbonate lake with high concentrations of lithium,boron,and potassium and obviously it differs from seawater in its chemical composition.An experimental simula...Zangnan Salt Lake on the south of the Tibet is a type of carbonate lake with high concentrations of lithium,boron,and potassium and obviously it differs from seawater in its chemical composition.An experimental simulation of the caloric evaporation of the lake’s brine was conducted byfirst freezing the brine and then performing isothermal evaporation at 288.15 K.The freezing path and the physicochemical properties of the brine were determined.The crystallization sequence was natron,hydrohalite,halite,sylvite,zabuyelite,trona,aphthitalite,thermonatrite,and borax.Rubidium and cesium salts did not crystallized out but concentrated in the mother solution.The physicochemical properties(density,refractive index,conductivity,and pH)of the liquid phase changed as the evaporation progressed.In the beginning of the evaporation processes,the concentration of potassium ions in the liquid phase gradually increased but later it decreased.A peak value of 55.21 g/L was obtained when the evaporation was 88%complete.When the mineral aphthitalite began to crystallize;the concentra-tions of B2O3,Li+,Rb+,and Cs+gradually increased as the evaporation progressed.When the evaporation was 98%complete,their concentrations in the mother liquor were 40.77 g/L,4.838 g/L,400.17 mg/L and 31.95 mg/L,respectively.This essential fundamental study can provide an important reference for the comprehensive utilization of brines in Zangnan Salt Lake.展开更多
基金supported in part by the National Natural Science Foundation of China(Grant No.92060114)in part by the Sichuan Science and Technology Program(Nos.2022YFS0524 and 2022YFG0044).
文摘It is known that eddy current effect has a great influence on magnetic flux leakage testing(MFL).Usually,contacttype encoder wheels are used to measure MFL testing speed to evaluate the effect and further compensate testing signals.This speed measurement method is complicated,and inevitable abrasion and occasional slippage will reduce the measurement accuracy.In order to solve this problem,based on eddy current effect due to the relative movement,a speed measurement method is proposed,which is contactless and simple.In the high-speed MFL testing,eddy current induced in the specimen will cause an obvious modification to the applied field.This modified field,which is measured by Hall sensor,can be utilized to reflect the moving speed.Firstly,the measurement principle is illustrated based on Faraday’s law.Then,dynamic finite element simulations are conducted to investigate the modified magnetic field distribution.Finally,laboratory experiments are performed to validate the feasibility of the proposed method.The results show that Bmz(r1)and Bmx(r2)have a linear relation with moving speed,which could be used as an alternative measurement parameter.
基金supported by National Natural Science Foundation of China(No.51777165)the National Key Research and Development Program of China(Nos.2018YFF01010804 and 2016YFC0801200)
文摘This research mainly describes the generation and diagnosis of plasma using a wire-plate discharge device driven by different power supplies,aimed at investigating the effect of driving source parameters on micro-discharge induced by a corona.The influence of parameters such as waveform,duty ratio and bias voltage on discharge characteristics was explored preliminarily.Experiment results show that the determination of volt-ampere characteristics under different driving source waveforms indicates that the application of square and pulse waveforms shows great advantages over that of sawtooth and sinusoidal waveforms.Similarly,the photo-thermal effects of the system were investigated by comparing the high-voltage electrode temperature and relative emission intensity of N2(C^3Πu—>B^Πg,0-0,337 nm),where square and pulse waveforms also achieved better performance.But the pulse waveform had a slight advantage over the square waveform in terms of energy conversion.Further,investigations of the duty ratio and bias voltage applied on the pulse waveform were conducted,and the results indicate that the duty ratio could effectively improve the discharge power and thermal effect to a certain extent;however,the application of bias voltage on the pulse signal had little influence on the discharge power and thermal effect.
文摘Our previous study has showed that restraint stress inhibits T cell proliferation. Kv1.3 plays a key role in the lymphocyte activation process. Here, we investigate the effects of restraint stress on murine splenic T and B cell proliferation and the role of Kv1.3 in the process. 3H-TdR incorporation is used to determine changes in splenocyte proliferation stimulated by Con A or LPS between control and restraint stress groups. The data shows that restraint stress inhibits T cell and enhanced B cell proliferation. Data from RT-PCR and Western blotting shows that Kv1.3 gene and protein levels are downregulated in T cells and upregulated in B cells in stressed mice. To examine a possible cause-and-effect relationship between Kv1.3 and stress-affected lymphocyte proliferation, we employ various Kv1.3 specific blockers (quinine, 4-AP and TEA) to determine K+ channel function under restraint stress. The data shows that Kv1.3 blockers reverse the decreased T cell proliferation and increase B cell proliferation induced by restraint stress. These results indicate that Kv1.3 mediates restraint stress-induced modulation of T/B lymphocyte proliferation.
基金supported by the National Natural Science Foundation of China(91854209,31630035)the Chinese Institute for Brain Research(2020-NKX-XM-09)China Postdoctoral Science Foundation Grant(2019M660308).
文摘Hibernation is an adaptive behavior for some small animals to survive cold winter.Hibernating mammals usually down-regulate their body temperature from~37℃to only a few degrees.During the evolution,mammalian hibernators have inherited unique strategies to survive extreme conditions that may lead to disease or death in humans and other non-hibernators.Hibernating mammals can not only tolerant deep hypothermia,hypoxia and anoxia,but also protect them against osteoporosis,muscle atrophy,heart arrhythmia and ischemia-reperfusion injury.Finding the molecular and regulatory mechanisms underlying these adaptations will provide novel ideas for treating related human diseases.
基金supported by the National Natural Science Foundation of China(Nos.22203062,22078247,U1707602,U1507109)the Yangtze Scholars and Innovative Research Team in University of Ministry of Education of China(No.IRT17R81)。
文摘Radioisotope leaking from nuclear waste has become an intractable problem due to its gamma radiation and strong water solubility.In this work,a novel porous ZnFC-PA/PSF composite sphere was fabricated by immobilization of ferrocyanides modified zinc phytate into polysulfone(PSF)substrate for the treatment of Cs-contaminated water.The maximum adsorption capacity of ZnFC-PA/PSF was 305.38 mg/g,and the removal efficiency of Cs+was reached 94.27%within 2 hr.The ZnFC-PA/PSF presented favorable stability with negligible dissolution loss of Zn^(2+)and Fe^(2+)(<2%).The ZnFC-PA/PSF achieved high-selectivity towards Cs+(K_(d)=2.24×10^(4)mL/g)even in actual geothermal water.The adsorption mechanism was inferred to be the ion-exchange between Cs^(+)and K^(+).What’s more,ZnFC-PA/PSF worked well in the fixed-bed adsorption(E=91.92%),indicating the application potential for the hazardous Cs^(+)removal from wastewater.
基金the National Key Research and Development Program of China and the National Natural Science Foundation of China(NSFC)(Grant Nos.2018YFA0801001,32070824,31871458,2019YFA0802800,2016YFA0100500,31671500,81371264,31671177,and 2018YFA0800501).
文摘Mammals exhibit limited heart regeneration ability,which can lead to heart failure after myocardial infarction.In contrast,zebrafish exhibit remarkable cardiac regeneration capacity.Several cell types and signaling pathways have been reported to participate in this process.However,a comprehensive analysis of how different cells and signals interact and coordinate to regulate cardiac regeneration is unavailable.We collected major cardiac cell types from zebrafish and performed high-precision single-cell transcriptome analyses during both development and post-injury regeneration.We revealed the cellular heterogeneity as well as the molecular progress of cardiomyocytes during these processes,and identified a subtype of atrial cardiomyocyte exhibiting a stem-like state which may transdifferentiate into ventricular cardiomyocytes during regeneration.Furthermore,we identified a regeneration-induced cell(RIC)population in the epicardium-derived cells(EPDC),and demonstrated Angiopoietin 4(Angpt4)as a specific regulator of heart regeneration.angpt4 expression is specifically and transiently activated in RIC,which initiates a signaling cascade from EPDC to endocardium through the Tie2-MAPK pathway,and further induces activation of cathepsin K in cardiomyocytes through RA signaling.Loss of angpt4 leads to defects in scar tissue resolution and cardiomyocyte proliferation,while overexpression of angpt4 accelerates regeneration.Furthermore,we found that ANGPT4 could enhance proliferation of neonatal rat cardiomyocytes,and promote cardiac repair in mice after myocardial infarction,indicating that the function of Angpt4 is conserved in mammals.Our study provides a mechanistic understanding of heart regeneration at single-cell precision,identifies Angpt4 as a key regulator of cardiomyocyte proliferation and regeneration,and offers a novel therapeutic target for improved recovery after human heart injuries.
文摘控制感是人类的根本需要,相信世界稳定有序、"善有善报、恶有恶报"的正义动机可以帮助我们获得控制感.正义动机是一个内隐加工过程,指向他人遭遇(而非自身遭遇)或社会整体的正义动机是人类根深蒂固的价值判断和社会态度,但由于受传统方法社会赞许效应和样本偏差影响,如何在内隐层面准确测量和验证正义动机的他人凸显效应一直是正义研究的难题.因此,本研究采用词嵌入联想测验(word embedding association test)的词、句向量指标,检验正义动机在内隐水平上的他人凸显效应.微博语料库的词向量分析表明,"他人"-"正义"的余弦相似度(语义关联度)显著大于"自我"-"正义"余弦相似度;谷歌BERT模型的句向量分析也重复了上述结果.总之,基于机器学习的词嵌入联想测验证明了内隐正义动机的他人凸显效应,即人们在潜意识里相信他人(而非自己)遭遇或社会整体是个简单美好的正义世界.这提示我们,看似无序的网络世界却蕴含民众对社会秩序的强烈需要,而词嵌入联想测验也为无结构文本背后的社会态度测量提供了新的算法.
基金financial support from the Ministry of Science and Technology of the People's Republic of China(MOST,Nos.2017YFA0204501,2013CB834502)National Natural Science Foundation of China(NSFC,Nos.21773135,21473098 and 21421064)。
文摘Based on block copolymer assisted topochemical polymerization,a new strategy for facilely producing robust nanoporous membranes with controlled incorporation of functional groups onto nanopores is developed.As exemplified by preparing nanoporous polypyrrole decorated with amino acids,this strategy exhibits a high degree of freedom for tailoring the surface functionality in the created pores.
基金the financial support from the Ministry of Science and Technology of the People's Republic of China (MOST, Nos. 2017YFA0204501, 2013CB834502)the National Natural Science Foundation of China (NSFC, Nos. 21473098, 21121004, and 21421064)the Deutsche Forschungsgemeinschaft DFG (No. TRR61)
文摘Creating hotspots with significantly enhanced electromagnetic(EF) field, efficiently placing target molecules in hotspot region, and achieving uniform and reproducible Raman signals are three critical issues for developing high-performance SERS substrates. In this work, large area gold nanoparticle cluster pillar array with a gold mirror at bottom was facilely fabricated by combined use of nanosphere lithography and self-assembly approach. It is both theoretically and experimentally found that through multiple coupling interactions, the electromagnetic fields at interparticle gaps within the gold clusters were significantly enhanced in our three-dimentional(3D) pillar array substrates, which can result in one order of magnitude stronger as compared with random gold clusters on a two-dimentional planar case.Due to the periodic stucture, our substrates also possess the capbility of producing highly uniform and reproducible SERS signals. Attractively, in our case, a photoresponsive polymer was used for the formation of pillar array structure. Its unique photoinduced deformation makes it possible to reversibly open and close the gaps of the closely packed Au NP array, thus enabling efficient placement or entrapment of probe molecules into hotspot sites between adjacent nanoparticles.
基金Financial support from the State Key Program of the National Natural Science Foundation of China(Grant No.20836009)the Key Laboratory of Saline Lake Resources and Environmental Ministry of Land and Resources,and the Tianjin Key Laboratory of Marine Resources and Chemistry(No.200909)is greatly appreciated.
文摘Zangnan Salt Lake on the south of the Tibet is a type of carbonate lake with high concentrations of lithium,boron,and potassium and obviously it differs from seawater in its chemical composition.An experimental simulation of the caloric evaporation of the lake’s brine was conducted byfirst freezing the brine and then performing isothermal evaporation at 288.15 K.The freezing path and the physicochemical properties of the brine were determined.The crystallization sequence was natron,hydrohalite,halite,sylvite,zabuyelite,trona,aphthitalite,thermonatrite,and borax.Rubidium and cesium salts did not crystallized out but concentrated in the mother solution.The physicochemical properties(density,refractive index,conductivity,and pH)of the liquid phase changed as the evaporation progressed.In the beginning of the evaporation processes,the concentration of potassium ions in the liquid phase gradually increased but later it decreased.A peak value of 55.21 g/L was obtained when the evaporation was 88%complete.When the mineral aphthitalite began to crystallize;the concentra-tions of B2O3,Li+,Rb+,and Cs+gradually increased as the evaporation progressed.When the evaporation was 98%complete,their concentrations in the mother liquor were 40.77 g/L,4.838 g/L,400.17 mg/L and 31.95 mg/L,respectively.This essential fundamental study can provide an important reference for the comprehensive utilization of brines in Zangnan Salt Lake.