Aging increases the risks of various diseases and the vulnerability to death.Cellular senescence is a hallmark of aging that contributes greatly to aging and aging-related diseases.This study demonstrates that extrace...Aging increases the risks of various diseases and the vulnerability to death.Cellular senescence is a hallmark of aging that contributes greatly to aging and aging-related diseases.This study demonstrates that extracellular vesicles from human urine-derived stem cells(USC-EVs)efficiently inhibit cellular senescence in vitro and in vivo.The intravenous injection of USC-EVs improves cognitive function,increases physical fitness and bone quality,and alleviates aging-related structural changes in different organs of senescence-accelerated mice and natural aging mice.The anti-aging effects of USC-EVs are not obviously affected by the USC donors’ages,genders,or health status.Proteomic analysis reveals that USC-EVs are enriched with plasminogen activator urokinase(PLAU)and tissue inhibitor of metalloproteinases 1(TIMP1).These two proteins contribute importantly to the anti-senescent effects of USC-EVs associated with the inhibition of matrix metalloproteinases,cyclin-dependent kinase inhibitor 2A(P16INK4a),and cyclin-dependent kinase inhibitor 1A(P21cip1).These findings suggest a great potential of autologous USC-EVs as a promising anti-aging agent by transferring PLAU and TIMP1 proteins.展开更多
This paper proposes a novel joint channel estimation and beamforming scheme for the massive multiple-input-multiple-output(MIMO)frequency-division duplexing(FDD) wireless legitimate surveillance system. With the propo...This paper proposes a novel joint channel estimation and beamforming scheme for the massive multiple-input-multiple-output(MIMO)frequency-division duplexing(FDD) wireless legitimate surveillance system. With the proposed scheme,the monitor with the full duplex capability realizes the proactive eavesdropping of the suspicious link by leveraging the pilot attack approach. Specifically, exploiting the effective eavesdropping rate and the mean square error as performance metrics and setting a total power budget at the training and transmission phases,while guaranteeing the information from suspicious source can be successfully decode, joint pilot design,power allocation and beamforming strategy are formulated as optimization problems for the two objective functions: MSE and effective eavesdropping rate. A closed-form expression of the optimal pilot with the limited length can be obtained via the channel correlation. The optimal power problem at the training phase can be solved by a simple bisection method. Then,based on the obtained imperfect estimated channel,the jamming beamforming at monitor optimization algorithm is proposed by utilizing the convex Semidefinite Programming approach to maximize the effective eavesdropping rate. Numerical results show that the proposed joint pilot design, power allocation and beamforming optimization scheme can improve the surveillance performance of the legitimate monitor as compared to the existing passive eavesdropping and jamming-assisted eavesdropping.展开更多
To the Editor:Allergic bronchopulmonary aspergillosis(ABPA)is an allergic lung disease caused by hypersensitivity to antigens from Aspergillus,and it most commonly occurs in patients with asthma or cysticbrosis.[1]The...To the Editor:Allergic bronchopulmonary aspergillosis(ABPA)is an allergic lung disease caused by hypersensitivity to antigens from Aspergillus,and it most commonly occurs in patients with asthma or cysticbrosis.[1]The main clinical characteristics of the disease are those related to elevated serum immunoglubulin(Ig)E level,positive Aspergillus fumigatus(A.fumigatus)specic IgE/IgG,repeated pulmonary inltration,and bronchiectasis.However,due to the lack of unied diagnostic criteria and screening methods,ABPA is always underdiagnosed.In 2021,new diagnostic criteria were proposed for allergic bronchopulmonary mycosis(ABPM)in the Japanese population.展开更多
Precise and spatiotemporal control over the pesticide remains to be a challenge.More efficient controlled release systems(CRSs)have been developed to support the precise delivery of active ingredients.Herein,we incorp...Precise and spatiotemporal control over the pesticide remains to be a challenge.More efficient controlled release systems(CRSs)have been developed to support the precise delivery of active ingredients.Herein,we incorporated the photoremovable protecting groups(PRPGs)into phenamacril(PHE)and obtained two photo-responsive fungicides of NV-PHE and DEACM-PHE.The 4,5-dimethoxy-o-nitrobenzyl(NV)or 7-diethylaminocoumarin(DEACM)-caged PHE could release the active molecule PHE after irradiation of UV light and blue light,respectively.Optical properties and in-vitro/vivo fungicidal activities of NV-PHE and DEACM-PHE demonstrated the feasibility for light controlled release of PHE.DEACM-PHE could release 98%PHE by illumination of blue light.The irradiated DEACM-PHE could preserve the similar bioactivity of PHE,and significantly improve the in-vitro/vivo fungicidal activities compared to the non-irradiated DEACM-PHE.The optical controlled release of PHE from DEACM-PHE enabled the precise and spatiotemporal delivery of PHE,diversifying the development of CRSs for pesticide,and providing environmentfriendly agricultural applications with high pesticide efficiency.展开更多
Terahertz(THz)emission spectroscopy(TES)has emerged as a highly effective and versatile technique for investigating the photoelectric properties of diverse materials and nonlinear physical processes in the past few de...Terahertz(THz)emission spectroscopy(TES)has emerged as a highly effective and versatile technique for investigating the photoelectric properties of diverse materials and nonlinear physical processes in the past few decades.Concurrently,research on two-dimensional(2D)materials has experienced substantial growth due to their atomically thin structures,exceptional mechanical and optoelectronic properties,and the potential for applications in flexible electronics,sensing,and nanoelectronics.Specifically,these materials offer advantages such as tunable bandgap,high carrier mobility,wideband optical absorption,and relatively short carrier lifetime.By applying TES to investigate the 2D materials,their interfaces and heterostructures,rich information about the interplay among photons,charges,phonons and spins can be unfolded,which provides fundamental understanding for future applications.Thus it is timely to review the nonlinear processes underlying THz emission in 2D materials including optical rectification,photon-drag,high-order harmonic generation and spin-to-charge conversion,showcasing the rich diversity of the TES employed to unravel the complex nature of these materials.Typical applications based on THz emissions,such as THz lasers,ultrafast imaging and biosensors,are also discussed.Step further,we analyzed the unique advantages of spintronic terahertz emitters and the future technological advancements in the development of new THz generation mechanisms leading to advanced THz sources characterized by wide bandwidth,high power and integration,suitable for industrial and commercial applications.The continuous advancement and integration of TES with the study of 2D materials and heterostructures promise to revolutionize research in different areas,including basic materials physics,novel optoelectronic devices,and chips for post-Moore’s era.展开更多
Based on data from the Chinese Industrial Enterprises Database, this paper investigates the effect of "Internet Plus" on the trade destination mix at the enterprise level The analysis extends the classic dual margin...Based on data from the Chinese Industrial Enterprises Database, this paper investigates the effect of "Internet Plus" on the trade destination mix at the enterprise level The analysis extends the classic dual margins to three dimensions: destination extensive, destination intensive and destination structural margins. The paper suggests that connecting to the internet not only raises Chinese firms'propensity to export, but also extends the destination extensive margin. In addition, Internet Plus could create a synergistic effect for internet-enabled enterprises, that is, the development of the destination country's internet access benefits domestic firms'export participation. Finally, the paper finds that lnternet Plus, rather than increasing the intensive or structural margins, leads to the transfer of exports to lower-middle-income countries and helps firms achieve competitiveness and thus increases their profit. The paper provides an explanatory mechanism and empirical evidence for firms 'use of the internet to optimize export space.展开更多
A hyperbranched supramolecular polymer(HSP)is constructed based on the intermolecular inclusion complexation of bridged tris(permethyl-β-cyclodextrin)with Mn^(Ⅲ)-porphyrin bearing poly(ethylene glycol)(PEG)side chai...A hyperbranched supramolecular polymer(HSP)is constructed based on the intermolecular inclusion complexation of bridged tris(permethyl-β-cyclodextrin)with Mn^(Ⅲ)-porphyrin bearing poly(ethylene glycol)(PEG)side chains(Mn^(Ⅲ)-TPP),and characterized by UV/vis absorption spectroscopy,isothermal titration calorimetry(ITC),NMR,dynamic light scattering(DLS),atomic force microscopy(AFM)and transmission electron microscopy(TEM),respectively.The presence of permethyl-β-cyclodextrin can stabilize the low-valent Mn^(II)-TPP.In vitro cell experiment indicates that this HSP has no remarkable cellular toxicity against NIH 3T3 cells.In vitro MR imaging experiment indicates a slightly increased T_(1) relaxivity for this HSP compared to that for the linear supramolecular polymer.展开更多
Background The hippocampus and amygdala are densely interconnected structures that work together in multiple affective and cognitive processes that are important to the etiology of major depressive disorder(MDD).Each ...Background The hippocampus and amygdala are densely interconnected structures that work together in multiple affective and cognitive processes that are important to the etiology of major depressive disorder(MDD).Each of these structures consists of several heterogeneous subfields.We aim to explore the topologic properties of the volume-based intrinsic network within the hippocampus–amygdala complex in medication-nale patients with first-episode MDD.Methods High-resolution T1-weighted magnetic resonance imaging scans were acquired from 123 first-episode,medication-nale,and noncomorbid MDD patients and 81 age-,sex-,and education level-matched healthy control participants(HCs).The structural covariance network(SCN)was constructed for each group using the volumes of the hippocampal subfields and amygdala subregions;the weights of the edges were defined by the partial correlation coefficients between each pair of subfields/subregions,controlled for age,sex,education level,and intracranial volume.The global and nodal graphmetrics were calculated and compared between groups.Results Compared with HCs,the SCN within the hippocampus–amygdala complex in patients with MDD showed a shortened mean characteristic path length,reduced modularity,and reduced small-worldness index.At the nodal level,the left hippocampal tail showed increased measures of centrality,segregation,and integration,while nodes in the left amygdala showed decreased measures of centrality,segregation,and integration in patients with MDD compared with HCs.Conclusion Our results provide the first evidence of atypical topologic characteristics within the hippocampus–amygdala complex in patients with MDD using structure network analysis.It provides more delineate mechanism of those two structures that underlying neuropathologic process in MDD.展开更多
基金supported by the National Natural Science Foundation of China(Grant Nos.82125023,82072504,81871822,82172501,81801395,and 82200039)the Science and Technology Innovation Program of Hunan Province(Grant Nos.2020RC4008 and 2022RC1211,China)+4 种基金the China National Postdoctoral Program for Innovative Talents(Grant No.BX2021383,China)the Central South University InnovationDriven Research Programme(Grant Nos.2023CXQD001 and 2019CX014,China)the Hunan Province Natural Science Foundation of China(Grant Nos.2023JJ10094 and 2020JJ5883)the Youth Science Foundation of Xiangya Hospital(Grant No.2022Q07,China)the Hunan Provincial Innovation Foundation for Postgraduate(Grant Nos.2021ZZTS0342 and 2022ZZTS0239,China)。
文摘Aging increases the risks of various diseases and the vulnerability to death.Cellular senescence is a hallmark of aging that contributes greatly to aging and aging-related diseases.This study demonstrates that extracellular vesicles from human urine-derived stem cells(USC-EVs)efficiently inhibit cellular senescence in vitro and in vivo.The intravenous injection of USC-EVs improves cognitive function,increases physical fitness and bone quality,and alleviates aging-related structural changes in different organs of senescence-accelerated mice and natural aging mice.The anti-aging effects of USC-EVs are not obviously affected by the USC donors’ages,genders,or health status.Proteomic analysis reveals that USC-EVs are enriched with plasminogen activator urokinase(PLAU)and tissue inhibitor of metalloproteinases 1(TIMP1).These two proteins contribute importantly to the anti-senescent effects of USC-EVs associated with the inhibition of matrix metalloproteinases,cyclin-dependent kinase inhibitor 2A(P16INK4a),and cyclin-dependent kinase inhibitor 1A(P21cip1).These findings suggest a great potential of autologous USC-EVs as a promising anti-aging agent by transferring PLAU and TIMP1 proteins.
基金supported in part by the National Natural Science Foundation of China under Grants 61971176 and 61901156in part by the Anhui Provincial Natural Science Foundation under Grant 2008085QF281in part by the Fundamental Research Fund for the Central Universities of China under Grant JZ2021HGTB0081。
文摘This paper proposes a novel joint channel estimation and beamforming scheme for the massive multiple-input-multiple-output(MIMO)frequency-division duplexing(FDD) wireless legitimate surveillance system. With the proposed scheme,the monitor with the full duplex capability realizes the proactive eavesdropping of the suspicious link by leveraging the pilot attack approach. Specifically, exploiting the effective eavesdropping rate and the mean square error as performance metrics and setting a total power budget at the training and transmission phases,while guaranteeing the information from suspicious source can be successfully decode, joint pilot design,power allocation and beamforming strategy are formulated as optimization problems for the two objective functions: MSE and effective eavesdropping rate. A closed-form expression of the optimal pilot with the limited length can be obtained via the channel correlation. The optimal power problem at the training phase can be solved by a simple bisection method. Then,based on the obtained imperfect estimated channel,the jamming beamforming at monitor optimization algorithm is proposed by utilizing the convex Semidefinite Programming approach to maximize the effective eavesdropping rate. Numerical results show that the proposed joint pilot design, power allocation and beamforming optimization scheme can improve the surveillance performance of the legitimate monitor as compared to the existing passive eavesdropping and jamming-assisted eavesdropping.
基金funded by the National Natural Science Foundation of China(Nos.82270033 and 81873407)the Natural Science Foundation of Hunan province(No.2022JJ30924)
文摘To the Editor:Allergic bronchopulmonary aspergillosis(ABPA)is an allergic lung disease caused by hypersensitivity to antigens from Aspergillus,and it most commonly occurs in patients with asthma or cysticbrosis.[1]The main clinical characteristics of the disease are those related to elevated serum immunoglubulin(Ig)E level,positive Aspergillus fumigatus(A.fumigatus)specic IgE/IgG,repeated pulmonary inltration,and bronchiectasis.However,due to the lack of unied diagnostic criteria and screening methods,ABPA is always underdiagnosed.In 2021,new diagnostic criteria were proposed for allergic bronchopulmonary mycosis(ABPM)in the Japanese population.
基金This work was financially supported by the Natural Science Foundation of China(Nos.21877039,32072441)National Key Research and Development Program of China(No.2018YFD0200100)Innovation Program of Shanghai Municipal Education Commission(No.2017-01-07-00-02-E00037).
文摘Precise and spatiotemporal control over the pesticide remains to be a challenge.More efficient controlled release systems(CRSs)have been developed to support the precise delivery of active ingredients.Herein,we incorporated the photoremovable protecting groups(PRPGs)into phenamacril(PHE)and obtained two photo-responsive fungicides of NV-PHE and DEACM-PHE.The 4,5-dimethoxy-o-nitrobenzyl(NV)or 7-diethylaminocoumarin(DEACM)-caged PHE could release the active molecule PHE after irradiation of UV light and blue light,respectively.Optical properties and in-vitro/vivo fungicidal activities of NV-PHE and DEACM-PHE demonstrated the feasibility for light controlled release of PHE.DEACM-PHE could release 98%PHE by illumination of blue light.The irradiated DEACM-PHE could preserve the similar bioactivity of PHE,and significantly improve the in-vitro/vivo fungicidal activities compared to the non-irradiated DEACM-PHE.The optical controlled release of PHE from DEACM-PHE enabled the precise and spatiotemporal delivery of PHE,diversifying the development of CRSs for pesticide,and providing environmentfriendly agricultural applications with high pesticide efficiency.
基金the National Key Research and Development Program of China(2021YFA1200800)the National Natural Science Foundation of China(62004114 and 62174098)Tsinghua University Initiative Scientific Research Center,Beijing Municipal Science and Technology Commission(Z221100005822011)and Beijing Advanced Innovation Center.
文摘Terahertz(THz)emission spectroscopy(TES)has emerged as a highly effective and versatile technique for investigating the photoelectric properties of diverse materials and nonlinear physical processes in the past few decades.Concurrently,research on two-dimensional(2D)materials has experienced substantial growth due to their atomically thin structures,exceptional mechanical and optoelectronic properties,and the potential for applications in flexible electronics,sensing,and nanoelectronics.Specifically,these materials offer advantages such as tunable bandgap,high carrier mobility,wideband optical absorption,and relatively short carrier lifetime.By applying TES to investigate the 2D materials,their interfaces and heterostructures,rich information about the interplay among photons,charges,phonons and spins can be unfolded,which provides fundamental understanding for future applications.Thus it is timely to review the nonlinear processes underlying THz emission in 2D materials including optical rectification,photon-drag,high-order harmonic generation and spin-to-charge conversion,showcasing the rich diversity of the TES employed to unravel the complex nature of these materials.Typical applications based on THz emissions,such as THz lasers,ultrafast imaging and biosensors,are also discussed.Step further,we analyzed the unique advantages of spintronic terahertz emitters and the future technological advancements in the development of new THz generation mechanisms leading to advanced THz sources characterized by wide bandwidth,high power and integration,suitable for industrial and commercial applications.The continuous advancement and integration of TES with the study of 2D materials and heterostructures promise to revolutionize research in different areas,including basic materials physics,novel optoelectronic devices,and chips for post-Moore’s era.
基金This research was funded by the Key Project of Zhejiang Province Social Science Plan (No. 18NDJC001Z), the China Postdoctoral Science Foundation funded project (No. 2017M621898, No. 2018T110580), the Major Project of the National Social Science Foundation of China (No. 15ZDB 156), the Key Project of the National Natural Science Foundation of China (No. 71433002) and Zhejiang University REOD (No. 201801). Song deeply appreciates the excellent comments provided by Jean-Louis Arcand, Pinghan Liang, Linhui Yu and Shiqi Guo during his studies as a visiting fellow at the Graduate Institute, Geneva.
文摘Based on data from the Chinese Industrial Enterprises Database, this paper investigates the effect of "Internet Plus" on the trade destination mix at the enterprise level The analysis extends the classic dual margins to three dimensions: destination extensive, destination intensive and destination structural margins. The paper suggests that connecting to the internet not only raises Chinese firms'propensity to export, but also extends the destination extensive margin. In addition, Internet Plus could create a synergistic effect for internet-enabled enterprises, that is, the development of the destination country's internet access benefits domestic firms'export participation. Finally, the paper finds that lnternet Plus, rather than increasing the intensive or structural margins, leads to the transfer of exports to lower-middle-income countries and helps firms achieve competitiveness and thus increases their profit. The paper provides an explanatory mechanism and empirical evidence for firms 'use of the internet to optimize export space.
基金We thank the 973 Program(No.2011CB932500)the NNSFC(Nos.20932004,21372128 and 91227107)for financial support.
文摘A hyperbranched supramolecular polymer(HSP)is constructed based on the intermolecular inclusion complexation of bridged tris(permethyl-β-cyclodextrin)with Mn^(Ⅲ)-porphyrin bearing poly(ethylene glycol)(PEG)side chains(Mn^(Ⅲ)-TPP),and characterized by UV/vis absorption spectroscopy,isothermal titration calorimetry(ITC),NMR,dynamic light scattering(DLS),atomic force microscopy(AFM)and transmission electron microscopy(TEM),respectively.The presence of permethyl-β-cyclodextrin can stabilize the low-valent Mn^(II)-TPP.In vitro cell experiment indicates that this HSP has no remarkable cellular toxicity against NIH 3T3 cells.In vitro MR imaging experiment indicates a slightly increased T_(1) relaxivity for this HSP compared to that for the linear supramolecular polymer.
基金This study is supported by grants from 1.3.5 Project for Disciplines of Excellence,West China Hospital,Sichuan University(ZYJC21041)The Research Project of Shanghai Science and Technology Commission(20dz2260300)The Fundamental Research Funds for the Central Universities.
文摘Background The hippocampus and amygdala are densely interconnected structures that work together in multiple affective and cognitive processes that are important to the etiology of major depressive disorder(MDD).Each of these structures consists of several heterogeneous subfields.We aim to explore the topologic properties of the volume-based intrinsic network within the hippocampus–amygdala complex in medication-nale patients with first-episode MDD.Methods High-resolution T1-weighted magnetic resonance imaging scans were acquired from 123 first-episode,medication-nale,and noncomorbid MDD patients and 81 age-,sex-,and education level-matched healthy control participants(HCs).The structural covariance network(SCN)was constructed for each group using the volumes of the hippocampal subfields and amygdala subregions;the weights of the edges were defined by the partial correlation coefficients between each pair of subfields/subregions,controlled for age,sex,education level,and intracranial volume.The global and nodal graphmetrics were calculated and compared between groups.Results Compared with HCs,the SCN within the hippocampus–amygdala complex in patients with MDD showed a shortened mean characteristic path length,reduced modularity,and reduced small-worldness index.At the nodal level,the left hippocampal tail showed increased measures of centrality,segregation,and integration,while nodes in the left amygdala showed decreased measures of centrality,segregation,and integration in patients with MDD compared with HCs.Conclusion Our results provide the first evidence of atypical topologic characteristics within the hippocampus–amygdala complex in patients with MDD using structure network analysis.It provides more delineate mechanism of those two structures that underlying neuropathologic process in MDD.