Numerous studies have shown that cell replacement therapy can replenish lost cells and rebuild neural circuitry in animal models of Parkinson’s disease.Transplantation of midbrain dopaminergic progenitor cells is a p...Numerous studies have shown that cell replacement therapy can replenish lost cells and rebuild neural circuitry in animal models of Parkinson’s disease.Transplantation of midbrain dopaminergic progenitor cells is a promising treatment for Parkinson’s disease.However,transplanted cells can be injured by mechanical damage during handling and by changes in the transplantation niche.Here,we developed a one-step biomanufacturing platform that uses small-aperture gelatin microcarriers to produce beads carrying midbrain dopaminergic progenitor cells.These beads allow midbrain dopaminergic progenitor cell differentiation and cryopreservation without digestion,effectively maintaining axonal integrity in vitro.Importantly,midbrain dopaminergic progenitor cell bead grafts showed increased survival and only mild immunoreactivity in vivo compared with suspended midbrain dopaminergic progenitor cell grafts.Overall,our findings show that these midbrain dopaminergic progenitor cell beads enhance the effectiveness of neuronal cell transplantation.展开更多
Zonal disintegration is the phenomenon of cyclical rupture zone and nonrupture zone in the surrounding rock of a deep-buried chamber,which is different from that of a shallow chamber.Based on the finite difference sof...Zonal disintegration is the phenomenon of cyclical rupture zone and nonrupture zone in the surrounding rock of a deep-buried chamber,which is different from that of a shallow chamber.Based on the finite difference software FLAC3D,the numerical simulation of surrounding rock with different mechanical parameters was conducted by using the SU model(Bilinear Strain-Softening Ubiquitous-Joint).The influences of buried depth,cohesion,and internal friction angle of surrounding rock on zonal disintegration were analyzed to reveal the influence law.The results show that:(1)after the chamber excavation,multiple rupture zones gradually extend from the chamber surface or adjacent periphery to the deep surrounding rock.In the extension process,a single rupture zone may be forked into two or even multiple rupture zones,which cross each other and form the zonal disintegration zone.(2)Zonal disintegration is affected by bothσ(in situ stress)and U_(cs)(uniaxial compression strength).Smaller U_(cs)and largerσwill lead to zonal disintegration.(3)The zoning fracture is not obvious in the case ofσ≤U_(cs).In the reverse case,zoning fracture appears remarkably in the surrounding rock around the chamber.These results reveal the influence law of zonal disintegration and provide theoretical support for the design of deep-buried chambers.展开更多
We propose a metamaterial structure that can achieve electromagnetically induced transparency and polarization—independent of the incident wave. The structure consists of a regular octagonal frame and four L-shaped m...We propose a metamaterial structure that can achieve electromagnetically induced transparency and polarization—independent of the incident wave. The structure consists of a regular octagonal frame and four L-shaped metal wires arranged periodically. There is a strong transparent window at 4.28 GHz. Our calculation results are in good agreement with the simulation results. When changing the excitation polarization of the incident wave, the transmission spectrum remains stable. Furthermore, when we adjust the permittivity of the medium in front of the metamaterial, the frequency of the transmission valley shifts linearly with the change in permittivity. This structure can be independent of the polarization of the incident wave and has potential inspiration in fields such as sensing.展开更多
The exponential growth of bioinformatics tools in recent years has posed challenges for scientists in selecting the most suitable one for their data analysis assignments.Therefore,to aid scientists in making informed ...The exponential growth of bioinformatics tools in recent years has posed challenges for scientists in selecting the most suitable one for their data analysis assignments.Therefore,to aid scientists in making informed choices,a community-based platform that indexes and rates bioinformatics tools is urgently needed.In this study,we introduce Bio Treasury(http://biotreasury.rjmart.cn),an integrated communitybased repository that provides an interactive platform for users and developers to share their experiences in various bioinformatics tools.Bio Treasury offers a comprehensive collection of well-indexed bioinformatics software,tools,and databases,totaling over 10,000 entries.In the past two years,we have continuously improved and maintained Bio Treasury,adding several exciting features,including creating structured homepages for every tool and user,a hierarchical category of bioinformatics tools and classifying tools using large language model(LLM).Bio Treasury streamlines the tool submission process with intelligent auto-completion.Additionally,Bio Treasury provides a wide range of social features,for example,enabling users to participate in interactive discussions,rate tools,build and share tool collections for the public.We believe Bio Treasury can be a valuable resource and knowledge-sharing platform for the biomedical community.It empowers researchers to effectively discover and evaluate bioinformatics tools,fostering collaboration and advancing bioinformatics research.展开更多
Haploid pluripotent stem cells,such as haploid embryonic stem cells(haESCs),facilitate the genetic study of recessive traits.In vitro,fish haESCs maintain haploidy in both undifferentiated and differentiated states,bu...Haploid pluripotent stem cells,such as haploid embryonic stem cells(haESCs),facilitate the genetic study of recessive traits.In vitro,fish haESCs maintain haploidy in both undifferentiated and differentiated states,but whether mammalian haESCs can preserve pluripotency in the haploid state has not been tested.Here,wereport thatmousehaESCs can differentiate in vitro into haploid epiblast stem cells(haEpiSCs),which maintain an intact haploid genome,unlimited self-renewal potential,and durable pluripotency to differentiate into various tissues in vitro and in vivo.Mechanistically,the maintenance of self-renewal potential depends on the Activin/bFGF pathway.We further show that haEpiSCs can differentiate in vitro into haploid progenitor-like cells.When injected into the cytoplasm of an oocyte,androgenetic haEpiSC(ahaEpiSCs)can support embryonic development until midgestation(E12.5).Together,these resultsdemonstrate durable pluripotency inmousehaESCs andhaEpiSCs,aswell asthe valuable potential of using these haploid pluripotent stem cells in high-throughput genetic screening.展开更多
Indirect field oriented control(IFOC)has become a widely adopted solution for AC motor drives.Standard IFOC controls torque and rotor flux linkage via q-and d-axis current.Alternatively,deadbeat-direct torque and flux...Indirect field oriented control(IFOC)has become a widely adopted solution for AC motor drives.Standard IFOC controls torque and rotor flux linkage via q-and d-axis current.Alternatively,deadbeat-direct torque and flux control(DB-DTFC)has emerged as a promising motor control strategy for the future,which manipulates Volt-sec.vector directly.Air-gap torque and stator flux linkage are decoupled and independently controlled over each switching period.Stator flux linkage is used as a separated degree-of-freedom to manipulate losses dynamically without compromising torque dynamics and torque ripple.In voltage-limited operations,direct selection of Volt-sec.allows DB-DTFC to fully utilize the dc bus voltage and produce fast torque.A single control law is used over a wide speed range.This paper aims to provide a comparative overview of the two motor controls regarding their sensitivity to parameters,current-and voltage-limited operation,loss manipulation,and torque ripple during signal injection.Based on the comparison,the ultimate objective is to demonstrate the opportunities and remaining challenges in DB-DTFC.展开更多
Epigenetic reprogramming of somatic cells into induced pluripotent stem cells （iPSCs） by overexpression of defined factors holds great promise for disease modeling and regen- erative medicine （Takahashi and Yamanak...Epigenetic reprogramming of somatic cells into induced pluripotent stem cells （iPSCs） by overexpression of defined factors holds great promise for disease modeling and regen- erative medicine （Takahashi and Yamanaka, 2006; Robinton and Daley, 2012）. However, the stochastic reprogramming process often results in variable pluripotency levels of iPSC lines as measured by their in vivo developmental potential, which poses a huge challenge to the applications of high quality iPSCs （Hanna et al., 2010）. The activation status of an imprinted Dlkl-Dio3 region has been identified as a molecular marker for pluripotency （Liu et al., 2010; Stadtfeld et al.,展开更多
Parkinson’s Disease(PD),second only to Alzheimer’s disease,is a neurodegenerative disease,most commonly occurring in people over the age of 65 years and is mostly caused by loss of dopamine neurons[1].Clinically,mot...Parkinson’s Disease(PD),second only to Alzheimer’s disease,is a neurodegenerative disease,most commonly occurring in people over the age of 65 years and is mostly caused by loss of dopamine neurons[1].Clinically,motor symptoms such as resting tremor,motor retardation,muscular rigidity,and disturbance of postural balance are the main symptoms,followed by non-motor symptoms such as cognitive impairment,autonomic nervous system dysfunction,depression,and sleep disorder[2].In 2016,>6.1 million people were affected with PD globally,2.4 times the number in 1990.The large number of affected people,coupled with the high mortality and disability rates,has placed a great burden on society[3].Traditional treatment methods mainly include drugs and surgery and are supplemented by physical therapy.展开更多
Introducing a combination of transcription factors such as Oct4,Sox2,Klf4 and c-Myc（OSKM）enables reprogramming which converts somatic cells into induced pluripotent stem cells（i PSCs）（Takahashi and Yamanaka,2006...Introducing a combination of transcription factors such as Oct4,Sox2,Klf4 and c-Myc（OSKM）enables reprogramming which converts somatic cells into induced pluripotent stem cells（i PSCs）（Takahashi and Yamanaka,2006）.i PSCs play an important role in clinical and regenerative medicine because they can be utilized to model a specific disease or differentiate into functional cells for transplantation.Enhancing the efficiency of induction and improving the qualities of iPSCs are constant themes in this field.展开更多
基金supported by the National Key Research and Development Program of China,Nos.2017YFE0122900(to BH),2019YFA0110800(to WL),2019YFA0903802(to YW),2021YFA1101604(to LW),2018YFA0108502(to LF),and 2020YFA0804003(to JW)the National Natural Science Foundation of China,Nos.31621004(to WL,BH)and 31970821(to YW)+1 种基金CAS Project for Young Scientists in Basic Research,No.YSBR-041(to YW)Joint Funds of the National Natural Science Foundation of China,No.U21A20396(to BH)。
文摘Numerous studies have shown that cell replacement therapy can replenish lost cells and rebuild neural circuitry in animal models of Parkinson’s disease.Transplantation of midbrain dopaminergic progenitor cells is a promising treatment for Parkinson’s disease.However,transplanted cells can be injured by mechanical damage during handling and by changes in the transplantation niche.Here,we developed a one-step biomanufacturing platform that uses small-aperture gelatin microcarriers to produce beads carrying midbrain dopaminergic progenitor cells.These beads allow midbrain dopaminergic progenitor cell differentiation and cryopreservation without digestion,effectively maintaining axonal integrity in vitro.Importantly,midbrain dopaminergic progenitor cell bead grafts showed increased survival and only mild immunoreactivity in vivo compared with suspended midbrain dopaminergic progenitor cell grafts.Overall,our findings show that these midbrain dopaminergic progenitor cell beads enhance the effectiveness of neuronal cell transplantation.
基金National Natural Science Foundation of China,Grant/Award Number:52079068State Key Laboratory of Hydroscience and Hydraulic Engineering,Grant/Award Number:2021-KY-04Key Research and Development Plan of Ningxia Hui Autonomous Region,Grant/Award Number:2018BCG01003。
文摘Zonal disintegration is the phenomenon of cyclical rupture zone and nonrupture zone in the surrounding rock of a deep-buried chamber,which is different from that of a shallow chamber.Based on the finite difference software FLAC3D,the numerical simulation of surrounding rock with different mechanical parameters was conducted by using the SU model(Bilinear Strain-Softening Ubiquitous-Joint).The influences of buried depth,cohesion,and internal friction angle of surrounding rock on zonal disintegration were analyzed to reveal the influence law.The results show that:(1)after the chamber excavation,multiple rupture zones gradually extend from the chamber surface or adjacent periphery to the deep surrounding rock.In the extension process,a single rupture zone may be forked into two or even multiple rupture zones,which cross each other and form the zonal disintegration zone.(2)Zonal disintegration is affected by bothσ(in situ stress)and U_(cs)(uniaxial compression strength).Smaller U_(cs)and largerσwill lead to zonal disintegration.(3)The zoning fracture is not obvious in the case ofσ≤U_(cs).In the reverse case,zoning fracture appears remarkably in the surrounding rock around the chamber.These results reveal the influence law of zonal disintegration and provide theoretical support for the design of deep-buried chambers.
文摘We propose a metamaterial structure that can achieve electromagnetically induced transparency and polarization—independent of the incident wave. The structure consists of a regular octagonal frame and four L-shaped metal wires arranged periodically. There is a strong transparent window at 4.28 GHz. Our calculation results are in good agreement with the simulation results. When changing the excitation polarization of the incident wave, the transmission spectrum remains stable. Furthermore, when we adjust the permittivity of the medium in front of the metamaterial, the frequency of the transmission valley shifts linearly with the change in permittivity. This structure can be independent of the polarization of the incident wave and has potential inspiration in fields such as sensing.
基金supported by the National Key Research and Development Program of China(2021YFA1302100)the National Natural Science Foundation of China(82172861,32200542)+2 种基金the Young Elite Scientists Sponsorship Program by Guangzhou Association for Science and Technology(QT-2023-045)the Youth Talent Support Program of Guangdong Provincial Association for Science and Technology(SKXRC202313)the Young Talents Program of Sun Yat-sen University Cancer Center(YTP-SYSUCC-0033)。
文摘The exponential growth of bioinformatics tools in recent years has posed challenges for scientists in selecting the most suitable one for their data analysis assignments.Therefore,to aid scientists in making informed choices,a community-based platform that indexes and rates bioinformatics tools is urgently needed.In this study,we introduce Bio Treasury(http://biotreasury.rjmart.cn),an integrated communitybased repository that provides an interactive platform for users and developers to share their experiences in various bioinformatics tools.Bio Treasury offers a comprehensive collection of well-indexed bioinformatics software,tools,and databases,totaling over 10,000 entries.In the past two years,we have continuously improved and maintained Bio Treasury,adding several exciting features,including creating structured homepages for every tool and user,a hierarchical category of bioinformatics tools and classifying tools using large language model(LLM).Bio Treasury streamlines the tool submission process with intelligent auto-completion.Additionally,Bio Treasury provides a wide range of social features,for example,enabling users to participate in interactive discussions,rate tools,build and share tool collections for the public.We believe Bio Treasury can be a valuable resource and knowledge-sharing platform for the biomedical community.It empowers researchers to effectively discover and evaluate bioinformatics tools,fostering collaboration and advancing bioinformatics research.
基金supported by grants from the National Basic Research Program of China(2012CBA01300 to Q.Z.and 2014CB964800 to W.L.)the National Science Foundation of China(91319308 to Q.Z.).
文摘Haploid pluripotent stem cells,such as haploid embryonic stem cells(haESCs),facilitate the genetic study of recessive traits.In vitro,fish haESCs maintain haploidy in both undifferentiated and differentiated states,but whether mammalian haESCs can preserve pluripotency in the haploid state has not been tested.Here,wereport thatmousehaESCs can differentiate in vitro into haploid epiblast stem cells(haEpiSCs),which maintain an intact haploid genome,unlimited self-renewal potential,and durable pluripotency to differentiate into various tissues in vitro and in vivo.Mechanistically,the maintenance of self-renewal potential depends on the Activin/bFGF pathway.We further show that haEpiSCs can differentiate in vitro into haploid progenitor-like cells.When injected into the cytoplasm of an oocyte,androgenetic haEpiSC(ahaEpiSCs)can support embryonic development until midgestation(E12.5).Together,these resultsdemonstrate durable pluripotency inmousehaESCs andhaEpiSCs,aswell asthe valuable potential of using these haploid pluripotent stem cells in high-throughput genetic screening.
基金support provided by the Wisconsin Electric Machines and Power Electronics Consortium(WEMPEC)of the University of Wisconsin-Madison.
文摘Indirect field oriented control(IFOC)has become a widely adopted solution for AC motor drives.Standard IFOC controls torque and rotor flux linkage via q-and d-axis current.Alternatively,deadbeat-direct torque and flux control(DB-DTFC)has emerged as a promising motor control strategy for the future,which manipulates Volt-sec.vector directly.Air-gap torque and stator flux linkage are decoupled and independently controlled over each switching period.Stator flux linkage is used as a separated degree-of-freedom to manipulate losses dynamically without compromising torque dynamics and torque ripple.In voltage-limited operations,direct selection of Volt-sec.allows DB-DTFC to fully utilize the dc bus voltage and produce fast torque.A single control law is used over a wide speed range.This paper aims to provide a comparative overview of the two motor controls regarding their sensitivity to parameters,current-and voltage-limited operation,loss manipulation,and torque ripple during signal injection.Based on the comparison,the ultimate objective is to demonstrate the opportunities and remaining challenges in DB-DTFC.
基金supported by the grants from the "Strategic Priority Research Program" of the Chinese Academy of Sciences (No. XDA01020100 to Q.Z.)the China National Basic Research Program (No. 2012CBA01300 to Q.Z.)the National Science Foundation of China (No. 91319308 to Q.Z.,31201105 to L.L. and 31371516 to W.L.)
文摘Epigenetic reprogramming of somatic cells into induced pluripotent stem cells （iPSCs） by overexpression of defined factors holds great promise for disease modeling and regen- erative medicine （Takahashi and Yamanaka, 2006; Robinton and Daley, 2012）. However, the stochastic reprogramming process often results in variable pluripotency levels of iPSC lines as measured by their in vivo developmental potential, which poses a huge challenge to the applications of high quality iPSCs （Hanna et al., 2010）. The activation status of an imprinted Dlkl-Dio3 region has been identified as a molecular marker for pluripotency （Liu et al., 2010; Stadtfeld et al.,
基金National Key R&D Program of China(2017YFA0105000)the National Natural Science Foundation of China(U1904207,81530037,91849115,and 82001973)+1 种基金the Provincial and Ministry of Health Construction Committee of Henan Province(SBGJ2020003017)the Excellent Youth Foundation of Henan Health Commission.
文摘Parkinson’s Disease(PD),second only to Alzheimer’s disease,is a neurodegenerative disease,most commonly occurring in people over the age of 65 years and is mostly caused by loss of dopamine neurons[1].Clinically,motor symptoms such as resting tremor,motor retardation,muscular rigidity,and disturbance of postural balance are the main symptoms,followed by non-motor symptoms such as cognitive impairment,autonomic nervous system dysfunction,depression,and sleep disorder[2].In 2016,>6.1 million people were affected with PD globally,2.4 times the number in 1990.The large number of affected people,coupled with the high mortality and disability rates,has placed a great burden on society[3].Traditional treatment methods mainly include drugs and surgery and are supplemented by physical therapy.
基金supported by the Strategic Priority Research Program of Chinese Academy of Sciences (No. XDA01020102)the grant from the Natural Science Foundation of China (No. 81225004)
文摘Introducing a combination of transcription factors such as Oct4,Sox2,Klf4 and c-Myc（OSKM）enables reprogramming which converts somatic cells into induced pluripotent stem cells（i PSCs）（Takahashi and Yamanaka,2006）.i PSCs play an important role in clinical and regenerative medicine because they can be utilized to model a specific disease or differentiate into functional cells for transplantation.Enhancing the efficiency of induction and improving the qualities of iPSCs are constant themes in this field.
