We investigated the asymmetric tension-compression(T-C)behavior of ZA21 bars with bimodal and uniform structures through axial tension and compression tests.The results show that the yield strengths of bars having bim...We investigated the asymmetric tension-compression(T-C)behavior of ZA21 bars with bimodal and uniform structures through axial tension and compression tests.The results show that the yield strengths of bars having bimodal structure are 206.42 and 140.28 MPa under tension and compression,respectively,which are higher than those of bars having uniform structure with tensile and compressive yield strength of 183.71 and 102.86 MPa,respectively.Prismatic slip and extension twinning under tension and basal slip and extension twinning under compression dominate the yield behavior and induce the T-C asymmetry.However,due to the basal slip activated in fine grains under tension and the inhibition of extension twinning by fine grains under compression,the bimodal structure possesses a lower T-C asymmetry(0.68)compared to the uniform structure(0.56).Multiple extension twins occur during deformation,and the selection of twin variants depends on the Schmid factor of the six variants activated by parent grains.Furthermore,the strengthening effect of the bimodal structure depends on the grain size and the ratio of coarse and fine grains.展开更多
In 2024,the Chinese Meridian Project(CMP)completed its construction,deploying 282 instruments across 31 stations.This achievement not only provides a robust foundation but also serves as a reference template for the I...In 2024,the Chinese Meridian Project(CMP)completed its construction,deploying 282 instruments across 31 stations.This achievement not only provides a robust foundation but also serves as a reference template for the International Meridian Circle Program(IMCP).The IMCP aims to integrate and establish a comprehensive network of ground-based monitoring stations designed to track the propagation of space weather events from the Sun to Earth.Additionally,it monitors various disturbances generated within the Earth system that impact geospace.Over the past two years,significant progress has been made on the IMCP.In particular,the second phase of construction for the China-Brazil Joint Laboratory for Space Weather has been completed,and the North Pole and Southeast Asia networks are under active construction.The 2024 IMCP joint observation campaign was successfully conducted.To facilitate these developments,the scientific program committee of IMCP was established,following the success of 2023 IMCP workshop and the space weather school,which was co-hosted with the Asia-Pacific Space Cooperation Organization(APSCO)and sponsored by Chinese Academy of Sciences(CAS)and Scientific Committee on Solar-Terrestrial Physics(SCOSTEP).Preparations are now underway for the 2024 workshop in collaboration with the National Institute for Space Research(INPE)in Brazil.展开更多
The Chinese Meridian Project(CMP)is a major national science and technology infrastructure constructed in two steps.The first phase of the CMP has been operating for more than a solar cycle.From 2022 to 2023,utilizing...The Chinese Meridian Project(CMP)is a major national science and technology infrastructure constructed in two steps.The first phase of the CMP has been operating for more than a solar cycle.From 2022 to 2023,utilizing the monitoring data collected by the CMP,scientists made major breakthroughs in fields of ionosphere,middle and upper atmosphere,and coupling between layers.The construction of the second phase of the CMP is nearly finished,and the project is expected to operate as a whole in 2025 after national acceptance of the second phase.The whole project was built in an architecture of so-called“One Chain,Three Networks and Four Focuses”.It is promising to make a three-dimensional observation of the whole solar-terrestrial space.The science community is looking forward to the great contribution of the CMP to space weather and space physics research.展开更多
Along with the surge of unearthed medical literature and cultural relics in recent years,a network of channels in the system of medical conduit vessels(meridians) during the early Western Han dynasty has become much c...Along with the surge of unearthed medical literature and cultural relics in recent years,a network of channels in the system of medical conduit vessels(meridians) during the early Western Han dynasty has become much clearer gradually.In it,the increasing number of channel branches,network vessels and needle insertion holes(acupoints) is an important feature of the development of channel medicine during the Western Han dynasty.This is not only a reflection of the expanding requirements of the theoretical system of the main trunk channels and other vessels,but also an inevitable result of the continuous enrichment and accumulation of clinical experience.This article integrates the information about channel branches,network vessels,inscriptions,dots and further relics on the Tianhui(天回) Lacquered Meridian Figurine to compare the unearthed literature of the channel genre with the transmitted classical literature about acupuncture.The “Heart-Regulated Channel” in Medical Manuscripts on Bamboo Slips from Tianhui(《天回医简》) serves as an example to explain the occurrence,development and changes of the channel branches and network vessels in the early system of medical channels.展开更多
The meridians,nervous system,and circulatory system are important components of tra‐ditional Chinese medicine and modern medicine.The meridians have a high degree of consistency with the distribution of the nervous a...The meridians,nervous system,and circulatory system are important components of tra‐ditional Chinese medicine and modern medicine.The meridians have a high degree of consistency with the distribution of the nervous and circulatory systems in modern medi‐cine,and are closely related in the process of disease treatment.Therefore,people often confuse the three.Based on the great advantages of acupuncture and moxibustion in the treatment of nervous system and circulatory system diseases,the author has made diver‐sified exploration on its relevance in terms of origin,physiological anatomy,physiological function and clinical application.It is believed that meridians have their relative indepen‐dence,and the nervous and circulatory systems cannot completely replace meridians.However,meridians are closely related to the nervous and circulatory systems,and in clinical practice,meridians can be combined with the nervous and circulatory systems to guide the treatment of diseases.展开更多
A novel yield criterion based on CPB06 considering anisotropic and tension-compression asymmetric behaviors of magnesium alloys was derived and proposed(called M_CPB06).This yield criterion can simultaneously predict ...A novel yield criterion based on CPB06 considering anisotropic and tension-compression asymmetric behaviors of magnesium alloys was derived and proposed(called M_CPB06).This yield criterion can simultaneously predict the yield stresses and the Lankford ratios at different angles(if any)under uniaxial tension,compression,equal-biaxial and equal-compression conditions.Then,in order to further describe the anisotropic strain-hardening characteristics of magnesium alloy,the proposed M_CPB06 criterion was further evolved to the M_CPB06ev model by expressing the parameters of the M_CPB06 model as functions of the plastic strain.As the model was developed,the stresses and Lankford ratios of AZ31B and ZK61M magnesium alloys at different angles under tensile,compressive and through-thickness compressive conditions were used to calibrate the M_CPB06/M_CPB06ev and the existing CPB06ex2 model.Calibration results reveal that compared with the CPB06ex2 yield criterion with equal quantity of coefficients,the M_CPB06 criterion exhibits certain advancement,and meanwhile the M_CPB06ev model can relatively accurately predict the change of the yield locus with increase of the plastic strain.Finally,the M_CPB06ev model was developed through UMAT in LS-DYNA.Finite element simulations using the subroutine were conducted on the specimens of different angles to the rolling direction under tension and compression.Simulation results were highly consistent with the experimental results,demonstrating a good reliability and accuracy of the developed subroutine.展开更多
Fatigue tests were conducted on tapered plain concrete prism specimens under tri axial constant-amplitude tension-compression cyclic loading. The low stress of the cyclic loading was taken as 0.2f c and the upper st...Fatigue tests were conducted on tapered plain concrete prism specimens under tri axial constant-amplitude tension-compression cyclic loading. The low stress of the cyclic loading was taken as 0.2f c and the upper stress ranged from 0. 20f t to 0.65f t. Three constant lateral pressures were 0.1f c, 0.2f c and 0.3f c respec tively. Based on the results, the th ree-stage evolution rule of the fatigue stiffness, maximum(minimum) longitudina l strain and damage were analyzed, and a unified S-N curve to calculate fati gue strength factors was worked out. The results show that the fatigue strength and fa tigue life under triaxial constant-amplitude tension-compression cyclic loadin g are smaller than those under uniaxial fatigue condition. Moreover, the secondary strain creep rate is related to the fatigue life, a formula for describing thei r relation was derived. The investigation of this paper can provide information for the fatigue design of concrete structures.展开更多
An experimental study on performance of plain concrete under triaxial constant-amplitude and variable amplitude tension- compression cyclic loadings was carded out. The low level of the cyclic stress is 0. 2f and the ...An experimental study on performance of plain concrete under triaxial constant-amplitude and variable amplitude tension- compression cyclic loadings was carded out. The low level of the cyclic stress is 0. 2f and the upper level ranges between 0. 20f and 0. 55f., while the constant lateral pressure is 0. 3 f . The specimen failure mode, the three-stage evolution rule of the longitudinal strains and the damage evolution law under cyclic loading were analyzed. Furthermore, Miner＇s rule is proved not to be applicable to the cyclic loading conditions, hereby, a nonlinear cumulative damage model was established. Based on the model the remaining fatigue life was evaluated. The comparison whh the experiment resuhs shaws that the model is of better precision and applicability.展开更多
[Objectives]To observe the clinical effect of acupuncture on blepharospasm.[Methods]72 patients were randomly divided into treatment group and control group with 36 cases in each group.In the treatment group,Shenmai,Z...[Objectives]To observe the clinical effect of acupuncture on blepharospasm.[Methods]72 patients were randomly divided into treatment group and control group with 36 cases in each group.In the treatment group,Shenmai,Zhaohai,Fengchi,Taichong,Fuyang,Jiaoxin and Jingming were selected as the main acupoints,while in the control group,routine acupoints were selected.With 4 weeks as a course of treatment,the two groups were compared after a course of treatment.The clinical effect of primary blepharospasm,blepharospasm intensity and scores of Hamilton Depression Scale were compared between the two groups before and after treatment.[Results]After treatment,the clinical efficacy of the two groups were significantly improved compared with that before treatment,the effective rate of the control group was 75.00%,the effective rate of the treatment group was 88.89%,indicating that the effective rate of control group was lower than that of the treatment group(P<0.05);after treatment,the degree of blepharospasm in both groups was significantly lower than that before treatment(P<0.05),and the treatment group had better effect in improving primary blepharospasm;the score of Hamilton depression scale in control group was lower than that in observation group(P<0.05).[Conclusions]The clinical curative effect of acupuncture at Yinqiao and Yangqiao meridians was better than that of conventional acupoints selected in relieving mild and moderate blepharospasm;it could definitely reduce the intensity of blepharospasm and relieve anxiety and depression of patients,so it is worthy of clinical promotion.展开更多
Objective :To observe the effect of electroacupuncture at pericardium meridian on neurological deficit, D-serine ( D-Ser ) content and NMDAR expression in ischemic brain tissue of rats with middle cerebral artery occl...Objective :To observe the effect of electroacupuncture at pericardium meridian on neurological deficit, D-serine ( D-Ser ) content and NMDAR expression in ischemic brain tissue of rats with middle cerebral artery occlusion ( MCAO ). Methods:A total of 36 SD rats were randomly divided into normal group, sham operation group, model group, EA pericardium meridian group, model+D-Ser group,and EA pericardium meridian+D-Ser group. The MCAO model was prepared by Zea Longa method. The model+D-Ser group and the EA pericardium meridian+D-Ser group were given exogenous D-Ser reagent(160 mg/kg i.p.) 30 minutes after the success of the insertion of the suture. EA pericardium meridian group and EA pericardium meridian+D-Ser group were treated with electroacupuncture for 30 min on the next day. The remaining groups were only bound for 30 min.Behavioral evaluation was performed at 6 h after successful modeling and 2 d after intervention, and then the rats were sacrificed. The content of D-Ser in ischemic brain tissue was measured by liquid chromatography tandem mass spectrometry, and the protein expression of NR1, NR2A and NR2B was detected by Western Blot. Results : Before treatment, compared with the normal group and the sham operation group, the behavioral scores of each group increased after modeling (P<0.05 );Compared with the model group, the behavioral scores of the model+D-Ser group and the EA pericardium meridian+D-Ser group were increased (P<0.05).After treatment, compared with the model group, there was no significant difference in the EA pericardium meridian group (P>0.05),The behavioral scores of the model+D-Ser group and the EA pericardium meridian+D-Ser group were still increased (P<0.05);Compared with the model+D-Ser group, the behavioral score of the EA pericardium meridian+D-Ser group was not statistically significant (P>0.05).Comparison before and after treatment in the group,except for the normal group and the sham operation group, the behavioral scores of each group were slightly increased, and the difference was not statistically significant (P>0.05).Compared with the model group, the content of D-Ser and the protein expression of NR1, NR2A and NR2B in the brain tissue of the model+D-Ser group were significantly increased (P<0.05);The protein expression of NR1, NR2A and NR2B decreased in EA pericardium meridian group (P<0.05);Compared with the model+ D-Ser group, the D-Ser content and the protein expression of NR1, NR2A and NR2B in the EA pericardium meridian+D-Ser group were decreased (P<0.05). Conclusion : EA at pericardium meridian points can reduce the D-Ser content in brain tissue of rats with acute MCAO, regulate the decrease of NR1, NR2A and NR2B protein expression, inhibit the NMDA receptor activity, and play a neuroprotective role.展开更多
基金financially supported by the National Natural Science Foundation of China (No. 52275305)the Fundamental Research Funds for the Central Universities (No. FRF-IC-20-10)the China Postdoctoral Science Foundation (No. 2021M700378)
文摘We investigated the asymmetric tension-compression(T-C)behavior of ZA21 bars with bimodal and uniform structures through axial tension and compression tests.The results show that the yield strengths of bars having bimodal structure are 206.42 and 140.28 MPa under tension and compression,respectively,which are higher than those of bars having uniform structure with tensile and compressive yield strength of 183.71 and 102.86 MPa,respectively.Prismatic slip and extension twinning under tension and basal slip and extension twinning under compression dominate the yield behavior and induce the T-C asymmetry.However,due to the basal slip activated in fine grains under tension and the inhibition of extension twinning by fine grains under compression,the bimodal structure possesses a lower T-C asymmetry(0.68)compared to the uniform structure(0.56).Multiple extension twins occur during deformation,and the selection of twin variants depends on the Schmid factor of the six variants activated by parent grains.Furthermore,the strengthening effect of the bimodal structure depends on the grain size and the ratio of coarse and fine grains.
基金Supported by International Meridian Circle Program Headquarters,China-Brazil Joint Laboratory for Space Weather(Y42347A99S)。
文摘In 2024,the Chinese Meridian Project(CMP)completed its construction,deploying 282 instruments across 31 stations.This achievement not only provides a robust foundation but also serves as a reference template for the International Meridian Circle Program(IMCP).The IMCP aims to integrate and establish a comprehensive network of ground-based monitoring stations designed to track the propagation of space weather events from the Sun to Earth.Additionally,it monitors various disturbances generated within the Earth system that impact geospace.Over the past two years,significant progress has been made on the IMCP.In particular,the second phase of construction for the China-Brazil Joint Laboratory for Space Weather has been completed,and the North Pole and Southeast Asia networks are under active construction.The 2024 IMCP joint observation campaign was successfully conducted.To facilitate these developments,the scientific program committee of IMCP was established,following the success of 2023 IMCP workshop and the space weather school,which was co-hosted with the Asia-Pacific Space Cooperation Organization(APSCO)and sponsored by Chinese Academy of Sciences(CAS)and Scientific Committee on Solar-Terrestrial Physics(SCOSTEP).Preparations are now underway for the 2024 workshop in collaboration with the National Institute for Space Research(INPE)in Brazil.
基金Supported by National Major Science and Technology Infrastructure Construction Project:the Chinese Meridian Project(2017-000052-73-01-002390)。
文摘The Chinese Meridian Project(CMP)is a major national science and technology infrastructure constructed in two steps.The first phase of the CMP has been operating for more than a solar cycle.From 2022 to 2023,utilizing the monitoring data collected by the CMP,scientists made major breakthroughs in fields of ionosphere,middle and upper atmosphere,and coupling between layers.The construction of the second phase of the CMP is nearly finished,and the project is expected to operate as a whole in 2025 after national acceptance of the second phase.The whole project was built in an architecture of so-called“One Chain,Three Networks and Four Focuses”.It is promising to make a three-dimensional observation of the whole solar-terrestrial space.The science community is looking forward to the great contribution of the CMP to space weather and space physics research.
基金one of the stage results of the Science and Technology Innovation Project (CI2021A00413) of the China Academy of Traditional Chinese Medicine。
文摘Along with the surge of unearthed medical literature and cultural relics in recent years,a network of channels in the system of medical conduit vessels(meridians) during the early Western Han dynasty has become much clearer gradually.In it,the increasing number of channel branches,network vessels and needle insertion holes(acupoints) is an important feature of the development of channel medicine during the Western Han dynasty.This is not only a reflection of the expanding requirements of the theoretical system of the main trunk channels and other vessels,but also an inevitable result of the continuous enrichment and accumulation of clinical experience.This article integrates the information about channel branches,network vessels,inscriptions,dots and further relics on the Tianhui(天回) Lacquered Meridian Figurine to compare the unearthed literature of the channel genre with the transmitted classical literature about acupuncture.The “Heart-Regulated Channel” in Medical Manuscripts on Bamboo Slips from Tianhui(《天回医简》) serves as an example to explain the occurrence,development and changes of the channel branches and network vessels in the early system of medical channels.
文摘The meridians,nervous system,and circulatory system are important components of tra‐ditional Chinese medicine and modern medicine.The meridians have a high degree of consistency with the distribution of the nervous and circulatory systems in modern medi‐cine,and are closely related in the process of disease treatment.Therefore,people often confuse the three.Based on the great advantages of acupuncture and moxibustion in the treatment of nervous system and circulatory system diseases,the author has made diver‐sified exploration on its relevance in terms of origin,physiological anatomy,physiological function and clinical application.It is believed that meridians have their relative indepen‐dence,and the nervous and circulatory systems cannot completely replace meridians.However,meridians are closely related to the nervous and circulatory systems,and in clinical practice,meridians can be combined with the nervous and circulatory systems to guide the treatment of diseases.
基金Beijing Natural Science Foundation(No.L201010)the United Fund of Ministry of Education for Equipment Pre-Research(Grant No.6141A02033121)National Natural Science Foundation of China(Grant No.51975041).
文摘A novel yield criterion based on CPB06 considering anisotropic and tension-compression asymmetric behaviors of magnesium alloys was derived and proposed(called M_CPB06).This yield criterion can simultaneously predict the yield stresses and the Lankford ratios at different angles(if any)under uniaxial tension,compression,equal-biaxial and equal-compression conditions.Then,in order to further describe the anisotropic strain-hardening characteristics of magnesium alloy,the proposed M_CPB06 criterion was further evolved to the M_CPB06ev model by expressing the parameters of the M_CPB06 model as functions of the plastic strain.As the model was developed,the stresses and Lankford ratios of AZ31B and ZK61M magnesium alloys at different angles under tensile,compressive and through-thickness compressive conditions were used to calibrate the M_CPB06/M_CPB06ev and the existing CPB06ex2 model.Calibration results reveal that compared with the CPB06ex2 yield criterion with equal quantity of coefficients,the M_CPB06 criterion exhibits certain advancement,and meanwhile the M_CPB06ev model can relatively accurately predict the change of the yield locus with increase of the plastic strain.Finally,the M_CPB06ev model was developed through UMAT in LS-DYNA.Finite element simulations using the subroutine were conducted on the specimens of different angles to the rolling direction under tension and compression.Simulation results were highly consistent with the experimental results,demonstrating a good reliability and accuracy of the developed subroutine.
基金Project supported by the National Natural Science Foundation of China(Grant No.50078010)
文摘Fatigue tests were conducted on tapered plain concrete prism specimens under tri axial constant-amplitude tension-compression cyclic loading. The low stress of the cyclic loading was taken as 0.2f c and the upper stress ranged from 0. 20f t to 0.65f t. Three constant lateral pressures were 0.1f c, 0.2f c and 0.3f c respec tively. Based on the results, the th ree-stage evolution rule of the fatigue stiffness, maximum(minimum) longitudina l strain and damage were analyzed, and a unified S-N curve to calculate fati gue strength factors was worked out. The results show that the fatigue strength and fa tigue life under triaxial constant-amplitude tension-compression cyclic loadin g are smaller than those under uniaxial fatigue condition. Moreover, the secondary strain creep rate is related to the fatigue life, a formula for describing thei r relation was derived. The investigation of this paper can provide information for the fatigue design of concrete structures.
文摘An experimental study on performance of plain concrete under triaxial constant-amplitude and variable amplitude tension- compression cyclic loadings was carded out. The low level of the cyclic stress is 0. 2f and the upper level ranges between 0. 20f and 0. 55f., while the constant lateral pressure is 0. 3 f . The specimen failure mode, the three-stage evolution rule of the longitudinal strains and the damage evolution law under cyclic loading were analyzed. Furthermore, Miner＇s rule is proved not to be applicable to the cyclic loading conditions, hereby, a nonlinear cumulative damage model was established. Based on the model the remaining fatigue life was evaluated. The comparison whh the experiment resuhs shaws that the model is of better precision and applicability.
文摘[Objectives]To observe the clinical effect of acupuncture on blepharospasm.[Methods]72 patients were randomly divided into treatment group and control group with 36 cases in each group.In the treatment group,Shenmai,Zhaohai,Fengchi,Taichong,Fuyang,Jiaoxin and Jingming were selected as the main acupoints,while in the control group,routine acupoints were selected.With 4 weeks as a course of treatment,the two groups were compared after a course of treatment.The clinical effect of primary blepharospasm,blepharospasm intensity and scores of Hamilton Depression Scale were compared between the two groups before and after treatment.[Results]After treatment,the clinical efficacy of the two groups were significantly improved compared with that before treatment,the effective rate of the control group was 75.00%,the effective rate of the treatment group was 88.89%,indicating that the effective rate of control group was lower than that of the treatment group(P<0.05);after treatment,the degree of blepharospasm in both groups was significantly lower than that before treatment(P<0.05),and the treatment group had better effect in improving primary blepharospasm;the score of Hamilton depression scale in control group was lower than that in observation group(P<0.05).[Conclusions]The clinical curative effect of acupuncture at Yinqiao and Yangqiao meridians was better than that of conventional acupoints selected in relieving mild and moderate blepharospasm;it could definitely reduce the intensity of blepharospasm and relieve anxiety and depression of patients,so it is worthy of clinical promotion.
基金National Natural Science Foundation of China (No.81774421)Natural Science Foundation of Hunan Province (No.2018JJ2306)Hunan Provincial General Project of Postgraduate Scientific Research Innovation (No.CX20200809)。
文摘Objective :To observe the effect of electroacupuncture at pericardium meridian on neurological deficit, D-serine ( D-Ser ) content and NMDAR expression in ischemic brain tissue of rats with middle cerebral artery occlusion ( MCAO ). Methods:A total of 36 SD rats were randomly divided into normal group, sham operation group, model group, EA pericardium meridian group, model+D-Ser group,and EA pericardium meridian+D-Ser group. The MCAO model was prepared by Zea Longa method. The model+D-Ser group and the EA pericardium meridian+D-Ser group were given exogenous D-Ser reagent(160 mg/kg i.p.) 30 minutes after the success of the insertion of the suture. EA pericardium meridian group and EA pericardium meridian+D-Ser group were treated with electroacupuncture for 30 min on the next day. The remaining groups were only bound for 30 min.Behavioral evaluation was performed at 6 h after successful modeling and 2 d after intervention, and then the rats were sacrificed. The content of D-Ser in ischemic brain tissue was measured by liquid chromatography tandem mass spectrometry, and the protein expression of NR1, NR2A and NR2B was detected by Western Blot. Results : Before treatment, compared with the normal group and the sham operation group, the behavioral scores of each group increased after modeling (P<0.05 );Compared with the model group, the behavioral scores of the model+D-Ser group and the EA pericardium meridian+D-Ser group were increased (P<0.05).After treatment, compared with the model group, there was no significant difference in the EA pericardium meridian group (P>0.05),The behavioral scores of the model+D-Ser group and the EA pericardium meridian+D-Ser group were still increased (P<0.05);Compared with the model+D-Ser group, the behavioral score of the EA pericardium meridian+D-Ser group was not statistically significant (P>0.05).Comparison before and after treatment in the group,except for the normal group and the sham operation group, the behavioral scores of each group were slightly increased, and the difference was not statistically significant (P>0.05).Compared with the model group, the content of D-Ser and the protein expression of NR1, NR2A and NR2B in the brain tissue of the model+D-Ser group were significantly increased (P<0.05);The protein expression of NR1, NR2A and NR2B decreased in EA pericardium meridian group (P<0.05);Compared with the model+ D-Ser group, the D-Ser content and the protein expression of NR1, NR2A and NR2B in the EA pericardium meridian+D-Ser group were decreased (P<0.05). Conclusion : EA at pericardium meridian points can reduce the D-Ser content in brain tissue of rats with acute MCAO, regulate the decrease of NR1, NR2A and NR2B protein expression, inhibit the NMDA receptor activity, and play a neuroprotective role.
