The impact of multi-directional compression passes on the microstructure,mechanical properties,and corrosion behavior of ZK60 magnesium alloy was investigated.Results reveal that severe dendrite segregation exists in ...The impact of multi-directional compression passes on the microstructure,mechanical properties,and corrosion behavior of ZK60 magnesium alloy was investigated.Results reveal that severe dendrite segregation exists in the as-cast ZK60 magnesium alloy with coarse MgZn phases distributed along the grain boundaries.After 9 passes of compression,the coarse solidified phases at the grain boundary are significantly refined,and back dissolution occurs.Fine recrystallized grains accompanied with the fine diffused nano-phases emerge in the local area around the large grains.The tensile strength of ZK60 magnesium alloy generally exhibits the upward trend with the increase in compression passes,whereas the compression rate shows the downward trend.The compressive strength reaches 433.6 MPa with the compression rate of 21.3%after 9 passes of compression.Multi-directional compression can significantly reduce the degradation rate of ZK60 magnesium alloy in simulated body fluids.Furthermore,it is observed that in the ascast ZK60 magnesium alloy,micro-segregation can easily lead to severe intragranular local corrosion.However,after multidirectional compression,the tendency to intragranular local corrosion is significantly diminished.展开更多
The pre-feasibility, report and dam site selection scheme of Guandi Hydropower Project has passed examination on the Examination Meeting held in Chengdu. Sichuan Province from March 16 to March 20. 1996. It indicates ...The pre-feasibility, report and dam site selection scheme of Guandi Hydropower Project has passed examination on the Examination Meeting held in Chengdu. Sichuan Province from March 16 to March 20. 1996. It indicates a step forward toward feasibility, study and the project be put in the state development program. The programmed Guandi Hydropover展开更多
NAN Rendong,a distinguished expert in radio astronomy who is known as the father of the world’s largest radio telescope,died from lung cancer in Boston on September 15,2017 at the age of 72.His untimely passing away ...NAN Rendong,a distinguished expert in radio astronomy who is known as the father of the world’s largest radio telescope,died from lung cancer in Boston on September 15,2017 at the age of 72.His untimely passing away was just ten days before his masterpiece,the Five-hundred-meter Aperture Spherical radio Telescope(FAST),which he spent over two decades conceiving and building for the next generation展开更多
The evolution of southwest Montana’s Big Hole and Beaverhead River drainage basins is determined from topographic map evidence related to mountain passes crossing what are today high altitude drainage divides includi...The evolution of southwest Montana’s Big Hole and Beaverhead River drainage basins is determined from topographic map evidence related to mountain passes crossing what are today high altitude drainage divides including North America’s east-west Continental Divide. Map evidence, such as orientations of valleys leading away from mountain passes (and saddles) and barbed tributaries found along the downstream drainage routes, is used to reconstruct flow directions of streams and rivers that once crossed the present-day high mountain divides. Large south-oriented anastomosing complexes of diverging and converging channels are interpreted to have eroded what are today closely spaced passes and saddles now notched into high mountain ridges. Water in those south-oriented channels is interpreted to have flowed across emerging mountains and subsiding basins. Headward erosion of deeper southeast-oriented valleys, assisted by crustal warping, concentrated south-oriented water in fewer and deeper valleys as the water flowed from southwest Montana into what are today Idaho and the Snake River drainage basin. Headward erosion of the Big Hole River valley between the emerging Anaconda and Pioneer Mountains, also assisted by crustal warping, reversed all Big Hole Basin drainage so as to create the north-, east-, and south-oriented Big Hole River drainage route. A final and even more major reversal of flow in the present-day north-oriented Montana Missouri River valley, with the assistance of additional crustal warping, next ended all remaining flow to Idaho and the Snake River drainage basin and reversed and captured all drainage in the present-day north-oriented Big Hole, Beaverhead, and Red Rock River drainage basins. The observed map evidence indicates that prior to the final flow reversal events, large volumes of south-oriented water flowed across southwest Montana’s Big Hole and Beaverhead River drainage basins.展开更多
Lang Rongbiao and Hou Dongmei,a couple living in North China's Tianjin Municipality,are retired professional athletes who won numerous awards during wushu(Chinese martial arts)competitions,both at home and abroad....Lang Rongbiao and Hou Dongmei,a couple living in North China's Tianjin Municipality,are retired professional athletes who won numerous awards during wushu(Chinese martial arts)competitions,both at home and abroad.Now,they are the principal and head coach,respectively,of a Tianjin-based martial arts school.Working together,they educate and cultivate wushu talents for China.What's more,the couple is dedicated to sharing the unique spirit of Chinese martial arts with the world.展开更多
2024年日本机床展览会(JIMTOF2024)于2024年11月5~10日在东京Tokyo Big Sight举办,展出面积118540平方米。展会以“技术传承提供无限可能(Technologies passed down to the future offer unlimited possibilities)”为主题。
目的:利用患者可接受症状状态结合波士顿腕管问卷评分对比患者对自制开窗式透明管道辅助关节镜微创双切口入路与常规开放单切口入路这两种手术方案术后患肢功能状态的满意度,以此来比较这两种手术方案的疗效。方法:通过电话回访进行两个...目的:利用患者可接受症状状态结合波士顿腕管问卷评分对比患者对自制开窗式透明管道辅助关节镜微创双切口入路与常规开放单切口入路这两种手术方案术后患肢功能状态的满意度,以此来比较这两种手术方案的疗效。方法:通过电话回访进行两个PASS锚定问题调查并完成波士顿腕管问卷,对数据进行统计学分析。结果:在平均12 ± 1月的随访中,内镜组PASS(+)患者占总体患者比例大于开放组,且内镜患者的SSS和FSS分数显著低于开放组患者。结论:患者对自制开窗式透明管道辅助关节镜微创双切口入路术后症状状态接受程度较高。Objective: To compare the postoperative functional outcomes and patient satisfaction between two surgical approaches for carpal tunnel syndrome—self-made fenestrated transparent cannula-assisted endoscopic minimally invasive double-incision approach and conventional open single-incision approach—using Patient Acceptable Symptom State (PASS) combined with Boston Carpal Tunnel Questionnaire (BCTQ) scores. Methods: A telephone follow-up was conducted to administer two PASS anchor questions and complete the BCTQ. Data were analyzed statistically to evaluate differences in symptom severity, functional status, and patient-reported satisfaction. Results: At a mean follow-up of 12 ± 1 months, the proportion of PASS(+) patients in the endoscopic group was significantly higher than that in the open group. Additionally, the endoscopic group demonstrated significantly lower Symptom Severity Scale (SSS) and Functional Status Scale (FSS) scores compared to the open group. Conclusion: Patients demonstrated a high level of acceptance toward their postoperative symptom status following the arthroscopic minimally invasive dual-incision approach assisted by a custom-made fenestrated transparent sheath.展开更多
Glaucoma is a multifactorial eye disorder that can cause vision loss and irreversible blindness,affecting individ uals aged 40 to 80 yea rs worldwide.Due to the aging population,it is expected that the number of peopl...Glaucoma is a multifactorial eye disorder that can cause vision loss and irreversible blindness,affecting individ uals aged 40 to 80 yea rs worldwide.Due to the aging population,it is expected that the number of people affected by glaucoma will surpass 111 million by 2040 as the disease becomes more prevalent.Glaucoma primarily contributes to optic nerve axon loss and the progressive degeneration of retinal ganglion cells (RGCs),subsequently leading to vision impairment.展开更多
Over the last two decades,the dogma that cell fate is immutable has been increasingly challenged,with important implications for regenerative medicine.The brea kth rough discovery that induced pluripotent stem cells c...Over the last two decades,the dogma that cell fate is immutable has been increasingly challenged,with important implications for regenerative medicine.The brea kth rough discovery that induced pluripotent stem cells could be generated from adult mouse fibroblasts is powerful proof that cell fate can be changed.An exciting extension of the discovery of cell fate impermanence is the direct cellular reprogram ming hypothesis-that terminally differentiated cells can be reprogrammed into other adult cell fates without first passing through a stem cell state.展开更多
Information on the effect of soil compaction on soil mechanical properties such as degree of compaction,compression and shear strength of tropical soils of Nigeria under different machinery traffic passes is very scar...Information on the effect of soil compaction on soil mechanical properties such as degree of compaction,compression and shear strength of tropical soils of Nigeria under different machinery traffic passes is very scarce.Field experiment was conducted in a tilled and compacted sandy clay loam(Alfisol)in Akure,Nigeria,under different machinery traffic passes to determine compaction effects on bulk density,compression strength,degree of compaction and the shear strength of soil.Four plots,A,B,C and D of area 20 m×50 m each were used for the field experiment.Treatment plot A was tilled with a tractor-mounted disc plough,and the remaining three plots:B,C and D were subjected to 5,10 and 15 to and fro passes,respectively,using heavy duty Mercy Fergusson tractor model 4355(3.82 Mg).The treatments were replicated three times in a randomized complete block design.Compacted plots progressively increased the bulk density from 1.63 g/cm^(3) to 1.90 g/cm^(3),but the highest bulk density was observed in plots under 15 traffic passes with the value of(1.90±0.23)g/cm3.The percentage of soil compaction varies from 90.5%to 97%at the 0-10 cm soil layer.The compression strength of soil increased from 31.00 kPa to 42.05 kPa and from 29.68 to 65.44 kPa at the 0-10 cm and 10-20 cm soil layers,respectively,which resulted in the increased shear strength from 15.79 kPa to 21.03 kPa and 14.8 kPa to 32.72 kPa at the 0-10 cm and 10-20 cm in plots under 5 and 15 traffic passes,respectively.Plot A(tilled soil)had the lowest bulk density,degree of compaction and compression strength with values(1.51±0.19)g/cm^(3),88.2%,and(12.15±0.37)kPa,respectively,and consequently the lowest shear strength of(6.02±1.23)kPa,which enhanced air movement and microbial activities in the soil.Soil under 15 traffic passes,especially at the 10-20 cm soil layer,may result in poor root penetration when cropped but can be very reliable and consistent when used for structural purposes.展开更多
The former Vice-President of the International Council of Ophthalmology(ICO).Professor of Ophthalmology Emeritus Johns Hopkins University School of Medicine,Wilmer Eye Institute,USA.The first Director of the Departmen...The former Vice-President of the International Council of Ophthalmology(ICO).Professor of Ophthalmology Emeritus Johns Hopkins University School of Medicine,Wilmer Eye Institute,USA.The first Director of the Department of Ophthalmology and Visual Sciences,The Chinese University of Hong Kong China.The first Director of the Peking University Eye Center,China.展开更多
As animated blockbuster Ne Zha 2 and the video game Black Myth:Wukong have become all the rage globally,Chinese culture is in the international spotlight again.Since its release in January 29,Chinese animated film Ne ...As animated blockbuster Ne Zha 2 and the video game Black Myth:Wukong have become all the rage globally,Chinese culture is in the international spotlight again.Since its release in January 29,Chinese animated film Ne Zha 2 has been making history.It entered the list of the all-time global box office top 10 only 20 days later,with ticket sales surpassing RMB 12 billion.It is also the world’s highest-grossing animated movie of all time,and the highest-grosser in a single market.IMDb gave it an 8.3 rating as of February 20,reflecting its universal appeal.展开更多
Since its release on 29 January,the Chinese animated film Ne Zha 2 has been making history.It entered the list of the all-time global box office top 10 only 20 days later,with ticket sales surpassing 15 billion yuan($...Since its release on 29 January,the Chinese animated film Ne Zha 2 has been making history.It entered the list of the all-time global box office top 10 only 20 days later,with ticket sales surpassing 15 billion yuan($2.07 billion).IMDb,a global movie review platform,gave it an 8.2 rating as of 11 March,underscoring its broad appeal.展开更多
High-speed maglev trains(HSMTs)can run at high running speeds due to their unique design.The pressure waves that these trains generate while passing each other are therefore very intense,and can even have safety impli...High-speed maglev trains(HSMTs)can run at high running speeds due to their unique design.The pressure waves that these trains generate while passing each other are therefore very intense,and can even have safety implications.In order to reduce the transient impact of such waves,the standard k-ε turbulence model is used in this work to assess the effect of railway spacing on the aerodynamic loads,pressure and surrounding flow field of 600 km/h maglev trains passing each other in open air.The sliding mesh technique is used to determine the relative motion between the considered trains.The results show that the surface pressure is approximately linearly correlated with the square of the speed while the amplitude of the pressure wave on the train surface,side force,and rolling moment all have negative exponential relationships with the railway spacing.展开更多
基金Guangdong Ocean University Research Launch Project(060302062310)。
文摘The impact of multi-directional compression passes on the microstructure,mechanical properties,and corrosion behavior of ZK60 magnesium alloy was investigated.Results reveal that severe dendrite segregation exists in the as-cast ZK60 magnesium alloy with coarse MgZn phases distributed along the grain boundaries.After 9 passes of compression,the coarse solidified phases at the grain boundary are significantly refined,and back dissolution occurs.Fine recrystallized grains accompanied with the fine diffused nano-phases emerge in the local area around the large grains.The tensile strength of ZK60 magnesium alloy generally exhibits the upward trend with the increase in compression passes,whereas the compression rate shows the downward trend.The compressive strength reaches 433.6 MPa with the compression rate of 21.3%after 9 passes of compression.Multi-directional compression can significantly reduce the degradation rate of ZK60 magnesium alloy in simulated body fluids.Furthermore,it is observed that in the ascast ZK60 magnesium alloy,micro-segregation can easily lead to severe intragranular local corrosion.However,after multidirectional compression,the tendency to intragranular local corrosion is significantly diminished.
文摘The pre-feasibility, report and dam site selection scheme of Guandi Hydropower Project has passed examination on the Examination Meeting held in Chengdu. Sichuan Province from March 16 to March 20. 1996. It indicates a step forward toward feasibility, study and the project be put in the state development program. The programmed Guandi Hydropover
文摘NAN Rendong,a distinguished expert in radio astronomy who is known as the father of the world’s largest radio telescope,died from lung cancer in Boston on September 15,2017 at the age of 72.His untimely passing away was just ten days before his masterpiece,the Five-hundred-meter Aperture Spherical radio Telescope(FAST),which he spent over two decades conceiving and building for the next generation
文摘The evolution of southwest Montana’s Big Hole and Beaverhead River drainage basins is determined from topographic map evidence related to mountain passes crossing what are today high altitude drainage divides including North America’s east-west Continental Divide. Map evidence, such as orientations of valleys leading away from mountain passes (and saddles) and barbed tributaries found along the downstream drainage routes, is used to reconstruct flow directions of streams and rivers that once crossed the present-day high mountain divides. Large south-oriented anastomosing complexes of diverging and converging channels are interpreted to have eroded what are today closely spaced passes and saddles now notched into high mountain ridges. Water in those south-oriented channels is interpreted to have flowed across emerging mountains and subsiding basins. Headward erosion of deeper southeast-oriented valleys, assisted by crustal warping, concentrated south-oriented water in fewer and deeper valleys as the water flowed from southwest Montana into what are today Idaho and the Snake River drainage basin. Headward erosion of the Big Hole River valley between the emerging Anaconda and Pioneer Mountains, also assisted by crustal warping, reversed all Big Hole Basin drainage so as to create the north-, east-, and south-oriented Big Hole River drainage route. A final and even more major reversal of flow in the present-day north-oriented Montana Missouri River valley, with the assistance of additional crustal warping, next ended all remaining flow to Idaho and the Snake River drainage basin and reversed and captured all drainage in the present-day north-oriented Big Hole, Beaverhead, and Red Rock River drainage basins. The observed map evidence indicates that prior to the final flow reversal events, large volumes of south-oriented water flowed across southwest Montana’s Big Hole and Beaverhead River drainage basins.
文摘Lang Rongbiao and Hou Dongmei,a couple living in North China's Tianjin Municipality,are retired professional athletes who won numerous awards during wushu(Chinese martial arts)competitions,both at home and abroad.Now,they are the principal and head coach,respectively,of a Tianjin-based martial arts school.Working together,they educate and cultivate wushu talents for China.What's more,the couple is dedicated to sharing the unique spirit of Chinese martial arts with the world.
文摘2024年日本机床展览会(JIMTOF2024)于2024年11月5~10日在东京Tokyo Big Sight举办,展出面积118540平方米。展会以“技术传承提供无限可能(Technologies passed down to the future offer unlimited possibilities)”为主题。
文摘目的:利用患者可接受症状状态结合波士顿腕管问卷评分对比患者对自制开窗式透明管道辅助关节镜微创双切口入路与常规开放单切口入路这两种手术方案术后患肢功能状态的满意度,以此来比较这两种手术方案的疗效。方法:通过电话回访进行两个PASS锚定问题调查并完成波士顿腕管问卷,对数据进行统计学分析。结果:在平均12 ± 1月的随访中,内镜组PASS(+)患者占总体患者比例大于开放组,且内镜患者的SSS和FSS分数显著低于开放组患者。结论:患者对自制开窗式透明管道辅助关节镜微创双切口入路术后症状状态接受程度较高。Objective: To compare the postoperative functional outcomes and patient satisfaction between two surgical approaches for carpal tunnel syndrome—self-made fenestrated transparent cannula-assisted endoscopic minimally invasive double-incision approach and conventional open single-incision approach—using Patient Acceptable Symptom State (PASS) combined with Boston Carpal Tunnel Questionnaire (BCTQ) scores. Methods: A telephone follow-up was conducted to administer two PASS anchor questions and complete the BCTQ. Data were analyzed statistically to evaluate differences in symptom severity, functional status, and patient-reported satisfaction. Results: At a mean follow-up of 12 ± 1 months, the proportion of PASS(+) patients in the endoscopic group was significantly higher than that in the open group. Additionally, the endoscopic group demonstrated significantly lower Symptom Severity Scale (SSS) and Functional Status Scale (FSS) scores compared to the open group. Conclusion: Patients demonstrated a high level of acceptance toward their postoperative symptom status following the arthroscopic minimally invasive dual-incision approach assisted by a custom-made fenestrated transparent sheath.
基金supported by the National Institutes of Health grants EY034116 (to WKJ, KYK, and SHC) and AG081037 (to YIM and WKJ)。
文摘Glaucoma is a multifactorial eye disorder that can cause vision loss and irreversible blindness,affecting individ uals aged 40 to 80 yea rs worldwide.Due to the aging population,it is expected that the number of people affected by glaucoma will surpass 111 million by 2040 as the disease becomes more prevalent.Glaucoma primarily contributes to optic nerve axon loss and the progressive degeneration of retinal ganglion cells (RGCs),subsequently leading to vision impairment.
基金supported by Canada First Research Excellence Fund,Medicine by Design(to CMM)。
文摘Over the last two decades,the dogma that cell fate is immutable has been increasingly challenged,with important implications for regenerative medicine.The brea kth rough discovery that induced pluripotent stem cells could be generated from adult mouse fibroblasts is powerful proof that cell fate can be changed.An exciting extension of the discovery of cell fate impermanence is the direct cellular reprogram ming hypothesis-that terminally differentiated cells can be reprogrammed into other adult cell fates without first passing through a stem cell state.
文摘Information on the effect of soil compaction on soil mechanical properties such as degree of compaction,compression and shear strength of tropical soils of Nigeria under different machinery traffic passes is very scarce.Field experiment was conducted in a tilled and compacted sandy clay loam(Alfisol)in Akure,Nigeria,under different machinery traffic passes to determine compaction effects on bulk density,compression strength,degree of compaction and the shear strength of soil.Four plots,A,B,C and D of area 20 m×50 m each were used for the field experiment.Treatment plot A was tilled with a tractor-mounted disc plough,and the remaining three plots:B,C and D were subjected to 5,10 and 15 to and fro passes,respectively,using heavy duty Mercy Fergusson tractor model 4355(3.82 Mg).The treatments were replicated three times in a randomized complete block design.Compacted plots progressively increased the bulk density from 1.63 g/cm^(3) to 1.90 g/cm^(3),but the highest bulk density was observed in plots under 15 traffic passes with the value of(1.90±0.23)g/cm3.The percentage of soil compaction varies from 90.5%to 97%at the 0-10 cm soil layer.The compression strength of soil increased from 31.00 kPa to 42.05 kPa and from 29.68 to 65.44 kPa at the 0-10 cm and 10-20 cm soil layers,respectively,which resulted in the increased shear strength from 15.79 kPa to 21.03 kPa and 14.8 kPa to 32.72 kPa at the 0-10 cm and 10-20 cm in plots under 5 and 15 traffic passes,respectively.Plot A(tilled soil)had the lowest bulk density,degree of compaction and compression strength with values(1.51±0.19)g/cm^(3),88.2%,and(12.15±0.37)kPa,respectively,and consequently the lowest shear strength of(6.02±1.23)kPa,which enhanced air movement and microbial activities in the soil.Soil under 15 traffic passes,especially at the 10-20 cm soil layer,may result in poor root penetration when cropped but can be very reliable and consistent when used for structural purposes.
文摘The former Vice-President of the International Council of Ophthalmology(ICO).Professor of Ophthalmology Emeritus Johns Hopkins University School of Medicine,Wilmer Eye Institute,USA.The first Director of the Department of Ophthalmology and Visual Sciences,The Chinese University of Hong Kong China.The first Director of the Peking University Eye Center,China.
文摘As animated blockbuster Ne Zha 2 and the video game Black Myth:Wukong have become all the rage globally,Chinese culture is in the international spotlight again.Since its release in January 29,Chinese animated film Ne Zha 2 has been making history.It entered the list of the all-time global box office top 10 only 20 days later,with ticket sales surpassing RMB 12 billion.It is also the world’s highest-grossing animated movie of all time,and the highest-grosser in a single market.IMDb gave it an 8.3 rating as of February 20,reflecting its universal appeal.
文摘Since its release on 29 January,the Chinese animated film Ne Zha 2 has been making history.It entered the list of the all-time global box office top 10 only 20 days later,with ticket sales surpassing 15 billion yuan($2.07 billion).IMDb,a global movie review platform,gave it an 8.2 rating as of 11 March,underscoring its broad appeal.
基金supported by the National Natural Science Foundation of China(12372049)Fundamental Research Funds for the Central Universities(2682023ZTPY036)Research and Development Project of JDD For HTS Maglev Transportation System(JDDKYCF2024002).
文摘High-speed maglev trains(HSMTs)can run at high running speeds due to their unique design.The pressure waves that these trains generate while passing each other are therefore very intense,and can even have safety implications.In order to reduce the transient impact of such waves,the standard k-ε turbulence model is used in this work to assess the effect of railway spacing on the aerodynamic loads,pressure and surrounding flow field of 600 km/h maglev trains passing each other in open air.The sliding mesh technique is used to determine the relative motion between the considered trains.The results show that the surface pressure is approximately linearly correlated with the square of the speed while the amplitude of the pressure wave on the train surface,side force,and rolling moment all have negative exponential relationships with the railway spacing.
