With the rising incidence of cardiovascular diseases,the concomitant mortality and morbidity impose huge burdens on quality of life and societal costs.It is generally accepted that physical inactivity is one of the ma...With the rising incidence of cardiovascular diseases,the concomitant mortality and morbidity impose huge burdens on quality of life and societal costs.It is generally accepted that physical inactivity is one of the major risk factors for cardiac disease and that exercise benefits the heart in both physiological and pathologic conditions.However,the molecular mechanisms governing the cardioprotective effects exerted by exercise remain incompletely understood.Most recently,an increasing number of studies indicate the involvement of epigenetic modifications in the promotion of cardiac health and prevention of cardiac disease.Exercise and other lifestyle factors extensively induce epigenetic modifications,including DNA/RNA methylation,histone post-translational modifications,and non-coding RNAs in multiple tissues,which may contribute to their positive effects in human health and diseases.In addition,several studies have shown that maternal or paternal exercise prevents age-associated or high-fat dietinduced metabolic dysfunction in the offspring,reinforcing the importance of epigenetics in mediating the beneficial effects of exercise.It has been shown that exercise can directly modify cardiac epigenetics to promote cardiac health and protect the heart against various pathological processes,or it can modify epigenetics in other tissues,which reduces the risk of cardiac disease and affords cardioprotection through exerkines.An in-depth understanding of the epigenetic landscape of cardioprotective response to exercise will provide new therapeutic targets for cardiac diseases.This review,therefore,aimed to acquaint the cardiac community with the rapidly advancing and evolving field of exercise and epigenetics.展开更多
Background:Angiogenesis constitutes a major mechanism responsible for exercise-induced beneficial effects.Our previous study identified a cluster of differentially expressed extracellular vesicle microRNAs(miRNAs)afte...Background:Angiogenesis constitutes a major mechanism responsible for exercise-induced beneficial effects.Our previous study identified a cluster of differentially expressed extracellular vesicle microRNAs(miRNAs)after exercise and found that some of them act as exerkines.However,whether these extracellular vesicle miRNAs mediate the exercise-induced angiogenesis remains unknown.Methods:A 9-day treadmill training was used as an exercise model in C57BL/6 mice.Liver-specific adeno-associated virus 8 was used to knock down microRNA-122-5p(miR-122-5p).Human umbilical vein endothelial cells were used in vitro.Results:Among these differentially expressed extracellular vesicle miRNAs,miR-122-5p was identified as a potent pro-angiogenic factor that activated vascular endothelial growth factor signaling and promoted angiogenesis both in vivo and in vitro.Exercise increased circulating levels of miR-122-5p,which was produced mainly by the liver and shuttled by extracellular vesicles in mice.Inhibition of circulating miR-122-5p or liver-specific knockdown of miR-122-5p significantly abolished the exercise-induced pro-angiogenic effect in skeletal muscles,and exerciseimproved muscle performance in mice.Mechanistically,miR-122-5p promoted angiogenesis through shifting substrate preference to fatty acids in endothelial cells,and miR-122-5p upregulated endothelial cell fatty-acid utilization by targeting 1-acyl-sn-glycerol-3-phosphate acyltransferase(AGPAT1).In addition,miR-122-5p increased capillary density in perilesional skin tissues and accelerated wound healing in mice.Conclusion:These findings demonstrated that exercise promotes angiogenesis through upregulation of liver-derived extracellular vesicle miR-122-5p,which enhances fatty acid utilization by targeting AGPAT1 in endothelial cells,highlighting the therapeutic potential of miR-122-5p in tissue repair.展开更多
We propose a radio frequency(RF)transfer technique with passive phase noise compensation over a fiber-optic ring.By adopting different frequencies and same wavelength transmission and double sideband(DSB)with carrier ...We propose a radio frequency(RF)transfer technique with passive phase noise compensation over a fiber-optic ring.By adopting different frequencies and same wavelength transmission and double sideband(DSB)with carrier suppression(DSBCS)modulation,the impact of backscattering can be effectively suppressed.A stable RF signal can be obtained via frequency mixing at an arbitrary access site along the fiber-optic ring.As the two directional transmissions adopt the same fiber and same wavelength from the same laser,the bidirectional propagation symmetry can be maximally guaranteed.We experimentally demonstrate 2 GHz RF signal transfer along a 100 km standard single-mode fiber-optic ring.展开更多
We propose a passive compensation fiber-optic radio frequency（RF） transfer scheme with a nonsynchronized RF stable source during a round-trip time, which can avoid high-precision phase-locking and efficiently suppre...We propose a passive compensation fiber-optic radio frequency（RF） transfer scheme with a nonsynchronized RF stable source during a round-trip time, which can avoid high-precision phase-locking and efficiently suppress the effect of backscattering only using two wavelengths at the same time. A stable frequency signal is directly reproduced by frequency mixing at the remote site. The proposed scheme is validated by the experiment over a 40 km single mode fiber spool using nonsynchronized common commercial RF sources. The influence of the stability of nonsynchronized RF sources on the frequency transfer is investigated over different length fiber links.展开更多
We report an 8-channel wavelength-mode optical pulse interleaver on a silicon photonic chip.Wavelength-and mode-division multiplexing techniques are combined to increase the repetition rate of the pulses without addin...We report an 8-channel wavelength-mode optical pulse interleaver on a silicon photonic chip.Wavelength-and mode-division multiplexing techniques are combined to increase the repetition rate of the pulses without adding the complexity of a single dimension.The interleaver uses a cascaded Mach–Zehnder interferometer architecture as a wavelength-division(de)multiplexer,an asymmetric directional coupler as a mode(de)multiplexer,and various lengths of silicon waveguides as delay lines.A pulse sequence with a time interval of 125 ps is implemented with the repetition rate being eight times that of the initial one.The demonstrated wavelength-mode multiplexing approach opens a new route for the generation of high-speed optical pulses.展开更多
Our objectives are to examine the effects of hummock-depression spatial heterogeneity on plant communities and soil properties,and to understand the process of maintaining and adjusting microtopography-mediated hydrol...Our objectives are to examine the effects of hummock-depression spatial heterogeneity on plant communities and soil properties,and to understand the process of maintaining and adjusting microtopography-mediated hydrological inputs and their spatial fluctuations that produce obvious microhabitats.We set up 36 plots(1 m×1 m)and sampled 45 plant and 225 soil samples in flooded(FH)and non-flooded hummocks(NFH)and depressions of the marshy,and the surrounding non-wetland meadows as well as in the Yellow River Source Zone,west China.We evaluated whether the alpine marshy wetland has a fertile island effect by the comparison method.Our results show that hummock presence can increase the spatial heterogeneity of the microhabitat and promote the plant diversity and soil fertility of the Kobresia tibetica community.Plant height,coverage,above-ground biomass,species richness and diversity were significantly higher in the FH and NFH microhabitat than in the areas between hummocks and surrounding non-wetland meadows.Compared with broad alpine meadows,the hummock-depression complex provided a microhabitat favorable to the growth of Cyperaceae.In the 0-50 cm soil layer,the closer the soil layer was to the ground surface,the higher its soil organic carbon and total nitrogen contents.Thus,in deeper layers,the gap between soil nutrients in wetland hummock-depression microhabitat and in the surrounding alpine meadows becomes smaller.Hence,the wetland hummock-depression microhabitat formed a fertile island pattern.Therefore,these results contribute toward improving our understanding of ecosystem restoration in alpine marshy meadows.展开更多
基金This study was supported by grants from the National Key Research and Development Project(2019YFF0301600)National Natural Science Foundation of China(31930055,81870273,and 31871146)。
文摘With the rising incidence of cardiovascular diseases,the concomitant mortality and morbidity impose huge burdens on quality of life and societal costs.It is generally accepted that physical inactivity is one of the major risk factors for cardiac disease and that exercise benefits the heart in both physiological and pathologic conditions.However,the molecular mechanisms governing the cardioprotective effects exerted by exercise remain incompletely understood.Most recently,an increasing number of studies indicate the involvement of epigenetic modifications in the promotion of cardiac health and prevention of cardiac disease.Exercise and other lifestyle factors extensively induce epigenetic modifications,including DNA/RNA methylation,histone post-translational modifications,and non-coding RNAs in multiple tissues,which may contribute to their positive effects in human health and diseases.In addition,several studies have shown that maternal or paternal exercise prevents age-associated or high-fat dietinduced metabolic dysfunction in the offspring,reinforcing the importance of epigenetics in mediating the beneficial effects of exercise.It has been shown that exercise can directly modify cardiac epigenetics to promote cardiac health and protect the heart against various pathological processes,or it can modify epigenetics in other tissues,which reduces the risk of cardiac disease and affords cardioprotection through exerkines.An in-depth understanding of the epigenetic landscape of cardioprotective response to exercise will provide new therapeutic targets for cardiac diseases.This review,therefore,aimed to acquaint the cardiac community with the rapidly advancing and evolving field of exercise and epigenetics.
基金supported by the National Key Basic Research Program of China(2019YFF0301600 and 2020YFC2002900)National Natural Science Foundation of China(31930055,31871146,32071169,81870273,and 32071108)Major Basic Science Program of Shaanxi Provincial Natural Science Foundation of China(2016ZDJC-17).
文摘Background:Angiogenesis constitutes a major mechanism responsible for exercise-induced beneficial effects.Our previous study identified a cluster of differentially expressed extracellular vesicle microRNAs(miRNAs)after exercise and found that some of them act as exerkines.However,whether these extracellular vesicle miRNAs mediate the exercise-induced angiogenesis remains unknown.Methods:A 9-day treadmill training was used as an exercise model in C57BL/6 mice.Liver-specific adeno-associated virus 8 was used to knock down microRNA-122-5p(miR-122-5p).Human umbilical vein endothelial cells were used in vitro.Results:Among these differentially expressed extracellular vesicle miRNAs,miR-122-5p was identified as a potent pro-angiogenic factor that activated vascular endothelial growth factor signaling and promoted angiogenesis both in vivo and in vitro.Exercise increased circulating levels of miR-122-5p,which was produced mainly by the liver and shuttled by extracellular vesicles in mice.Inhibition of circulating miR-122-5p or liver-specific knockdown of miR-122-5p significantly abolished the exercise-induced pro-angiogenic effect in skeletal muscles,and exerciseimproved muscle performance in mice.Mechanistically,miR-122-5p promoted angiogenesis through shifting substrate preference to fatty acids in endothelial cells,and miR-122-5p upregulated endothelial cell fatty-acid utilization by targeting 1-acyl-sn-glycerol-3-phosphate acyltransferase(AGPAT1).In addition,miR-122-5p increased capillary density in perilesional skin tissues and accelerated wound healing in mice.Conclusion:These findings demonstrated that exercise promotes angiogenesis through upregulation of liver-derived extracellular vesicle miR-122-5p,which enhances fatty acid utilization by targeting AGPAT1 in endothelial cells,highlighting the therapeutic potential of miR-122-5p in tissue repair.
基金supported by the National Natural Science Foundation of China(NSFC)(Nos.61627817 and 61535006).
文摘We propose a radio frequency(RF)transfer technique with passive phase noise compensation over a fiber-optic ring.By adopting different frequencies and same wavelength transmission and double sideband(DSB)with carrier suppression(DSBCS)modulation,the impact of backscattering can be effectively suppressed.A stable RF signal can be obtained via frequency mixing at an arbitrary access site along the fiber-optic ring.As the two directional transmissions adopt the same fiber and same wavelength from the same laser,the bidirectional propagation symmetry can be maximally guaranteed.We experimentally demonstrate 2 GHz RF signal transfer along a 100 km standard single-mode fiber-optic ring.
基金supported by the National Natural Science Foundation of China(NSFC)(Nos.61627817 and 61535006)
文摘We propose a passive compensation fiber-optic radio frequency（RF） transfer scheme with a nonsynchronized RF stable source during a round-trip time, which can avoid high-precision phase-locking and efficiently suppress the effect of backscattering only using two wavelengths at the same time. A stable frequency signal is directly reproduced by frequency mixing at the remote site. The proposed scheme is validated by the experiment over a 40 km single mode fiber spool using nonsynchronized common commercial RF sources. The influence of the stability of nonsynchronized RF sources on the frequency transfer is investigated over different length fiber links.
文摘We report an 8-channel wavelength-mode optical pulse interleaver on a silicon photonic chip.Wavelength-and mode-division multiplexing techniques are combined to increase the repetition rate of the pulses without adding the complexity of a single dimension.The interleaver uses a cascaded Mach–Zehnder interferometer architecture as a wavelength-division(de)multiplexer,an asymmetric directional coupler as a mode(de)multiplexer,and various lengths of silicon waveguides as delay lines.A pulse sequence with a time interval of 125 ps is implemented with the repetition rate being eight times that of the initial one.The demonstrated wavelength-mode multiplexing approach opens a new route for the generation of high-speed optical pulses.
基金Thank the members of the research team for their kind support in the experiment,and thank the Science and Technology Department of Qinghai Provincial for the funding of the application basic project(2019-ZJ-7035)Discipline Innovation and Introducing Talents Program of Higher Education Institutions(the 111 Project,D18013)Changjiang Scholars and Innovation Team Development plan(IRT_17R62).
文摘Our objectives are to examine the effects of hummock-depression spatial heterogeneity on plant communities and soil properties,and to understand the process of maintaining and adjusting microtopography-mediated hydrological inputs and their spatial fluctuations that produce obvious microhabitats.We set up 36 plots(1 m×1 m)and sampled 45 plant and 225 soil samples in flooded(FH)and non-flooded hummocks(NFH)and depressions of the marshy,and the surrounding non-wetland meadows as well as in the Yellow River Source Zone,west China.We evaluated whether the alpine marshy wetland has a fertile island effect by the comparison method.Our results show that hummock presence can increase the spatial heterogeneity of the microhabitat and promote the plant diversity and soil fertility of the Kobresia tibetica community.Plant height,coverage,above-ground biomass,species richness and diversity were significantly higher in the FH and NFH microhabitat than in the areas between hummocks and surrounding non-wetland meadows.Compared with broad alpine meadows,the hummock-depression complex provided a microhabitat favorable to the growth of Cyperaceae.In the 0-50 cm soil layer,the closer the soil layer was to the ground surface,the higher its soil organic carbon and total nitrogen contents.Thus,in deeper layers,the gap between soil nutrients in wetland hummock-depression microhabitat and in the surrounding alpine meadows becomes smaller.Hence,the wetland hummock-depression microhabitat formed a fertile island pattern.Therefore,these results contribute toward improving our understanding of ecosystem restoration in alpine marshy meadows.
