Rocks in underground works usually experience rather complex stress disturbance.For this,their fracture mechanism is significantly different from rocks subjected to conventional triaxial compression conditions.The eff...Rocks in underground works usually experience rather complex stress disturbance.For this,their fracture mechanism is significantly different from rocks subjected to conventional triaxial compression conditions.The effects of stress disturbances on rock geomechanical behaviors under fatigue loading conditions and triaxial unloading conditions have been reported in previous studies.However,little is known about the dependence of the unloading rate on fatigue loading and confining stress unloading(FL-CSU)conditions that influence rock failure.In this paper,we aimed at investigating the fracture behaviors of marble under FL-CSU conditions using the post-test X-ray computed tomography(CT)scanning technique and the GCTS RTR 2000 rock mechanics system.Results show that damage accumulation at the fatigue stage can influence the final fracture behaviors of marble.The stored elastic energy for rock samples under FL-CSU tests is relatively larger compared to those under conventional triaxial tests,and the dissipated energy used to drive damage evolution and crack propagation is larger for FL-CSU tests.In FL-CSU tests,as the unloading rate increases,the dissipated energy grows and elastic energy reduces.CT scanning after the test reveals the impacts of the unloading rate on the crack pattern and a fracture degree index is therein defined in this context to represent the crack dimension.It shows that the crack pattern after FL-CSU tests depends on the unloading rate,and the fracture degree is in agreement with the analysis of both the energy dissipation and the amount of energy released.The effect of unloading rate on fracture evolution characteristics of marble is revealed by a series of FL-CSU tests.展开更多
The Circular Electron Positron Collider(CEPC)is a large scientific project initiated and hosted by China,fostered through extensive collaboration with international partners.The complex comprises four accelerators:a 3...The Circular Electron Positron Collider(CEPC)is a large scientific project initiated and hosted by China,fostered through extensive collaboration with international partners.The complex comprises four accelerators:a 30 GeV Linac,a 1.1 GeV Damping Ring,a Booster capable of achieving energies up to 180 GeV,and a Collider operating at varying energy modes(Z,W,H,and tt).The Linac and Damping Ring are situated on the surface,while the subterranean Booster and Collider are housed in a 100 km circumference underground tunnel,strategically accommodating future expansion with provisions for a potential Super Proton Proton Collider(SPPC).The CEPC primarily serves as a Higgs factory.In its baseline design with synchrotron radiation(SR)power of 30 MW per beam,it can achieve a luminosity of 5×10^(34)cm^(-2)s^(-1)per interaction point(IP),resulting in an integrated luminosity of 13 ab^(-1)for two IPs over a decade,producing 2.6 million Higgs bosons.Increasing the SR power to 50 MW per beam expands the CEPC's capability to generate 4.3 million Higgs bosons,facilitating precise measurements of Higgs coupling at sub-percent levels,exceeding the precision expected from the HL-LHC by an order of magnitude.This Technical Design Report(TDR)follows the Preliminary Conceptual Design Report(Pre-CDR,2015)and the Conceptual Design Report(CDR,2018),comprehensively detailing the machine's layout,performance metrics,physical design and analysis,technical systems design,R&D and prototyping efforts,and associated civil engineering aspects.Additionally,it includes a cost estimate and a preliminary construction timeline,establishing a framework for forthcoming engineering design phase and site selection procedures.Construction is anticipated to begin around 2027-2028,pending government approval,with an estimated duration of 8 years.The commencement of experiments and data collection could potentially be initiated in the mid-2030s.展开更多
We explore the possibility that domain wall networks generate the stochastic gravitational wave background(SGWB) observed as a strong common power-law process in the Data Release-2 of Parkes Pulsar Timing Array. We fi...We explore the possibility that domain wall networks generate the stochastic gravitational wave background(SGWB) observed as a strong common power-law process in the Data Release-2 of Parkes Pulsar Timing Array. We find that a broad range of parameters, specifically wall tension around σ_(DW)^(29-414 TeV)^(3) and wall-decay temperature within T_(d) ~ 20-257 MeV, can explain this phenomenon at a 68% credible level. Meanwhile, the same parameters could ease the Hubble tension if particles from these domain wall networks decay into dark radiation. We establish a direct analytical relationship, ΩGW(f_(p), T_(0))h^(2)~ Ω_(rad)h^(2)(Ω_νΩN_(eff))^(2),to illustrate this coincidence, underlining its importance in the underlying physics and potential applicability to a wider range of models and data. Conversely, if the common power-law process is not attributed to domain wall networks, our findings impose tight limits on the wall tension and decay temperature.展开更多
Laser hot wire cladding, with the prominent features of low heat input, high energy efficiency, and high precision, is widely used for remanufacturing metal parts. The cladding process, however, needs to be improved b...Laser hot wire cladding, with the prominent features of low heat input, high energy efficiency, and high precision, is widely used for remanufacturing metal parts. The cladding process, however, needs to be improved by using a quantitative method. In this work, volumetric defect ratio was proposed as the criterion to describe the integrity of forming quality for cladding layers. Laser deposition experiments with FV520B, one of martensitic stainless steels, were designed by using the Taguchi method. Four process variables, namely, laser power （P）, scanning speed （Vs）, wire feed rate （Vf）, and wire current （/）, were optimized based on the analysis of signal-to-noise （S/N） ratio. Metallurgic observation of cladding layer was conducted to compare the forming quality and to validate the analysis method. A stable and continuous process with the optimum parameter combination produced uniform microstructure with minimal defects and cracks, which resulted in a good metallurgical bonding interface.展开更多
Optical microcavities have the ability to confne photons in small mode volumes for long periods of time,greatly enhancing light-matter interactions,and have become one of the research hotspots in international academi...Optical microcavities have the ability to confne photons in small mode volumes for long periods of time,greatly enhancing light-matter interactions,and have become one of the research hotspots in international academia.In recent years,sensing applications in complex environments have inspired the development of multimode optical microcavity sensors.These multimode sensors can be used not only for multi-parameter detection but also to improve measurement precision.In this review,we introduce multimode sensing methods based on optical microcavities and present an overview of the multimode single/multi-parameter optical microcavities sensors.Expected further research activities are also put forward.展开更多
In order to realize the ultrastrong absorption of graphene with electrical modulation properties, we designed a composite structure of graphene and parity-time(PT) symmetry photonic crystal, which is achieved by placi...In order to realize the ultrastrong absorption of graphene with electrical modulation properties, we designed a composite structure of graphene and parity-time(PT) symmetry photonic crystal, which is achieved by placing the graphene layer on the top layer of the PT symmetry photonic crystal. In this paper, the absorption properties of graphene and the electrical modulating properties of the structure were theoretically analyzed based on the transfer matrix method. The result shows that the proposed structure can achieve the absorption of 31.5 d B for the communication wavelength of 1550 nm;meanwhile,by setting the electric field intensity to ±0.02 V/nm, the absorption of graphene can be largely modulated to realize an electrically switchable effect, the modulation depth of graphene absorption can reach nearly 100%, and the operation speed is also close to 8.171 GHz. This investigation provides a novel approach to design graphene-based optoelectronic devices and optical communication devices.展开更多
Glucokinase (GK) plays a pivotal role in glucose homeostasis as the glucose sensor in the pancreas and liver. Loss of function of GK results in hyperglycemia, and gain of function causes congenital hyperinsulinemic hy...Glucokinase (GK) plays a pivotal role in glucose homeostasis as the glucose sensor in the pancreas and liver. Loss of function of GK results in hyperglycemia, and gain of function causes congenital hyperinsulinemic hypoglycemia. We speculate that the progressive loss of GK at both messenger RNA (mRNA) and protein levels in the islets and liver would be the key mechanism for Type 2 diabetes (T2D) pathogenesis. The development of GK activator (GKA) as an anti-diabetic drug has been endeavored for several decades. The failure of the early development of GKAs is due to the limitation of understanding the mode of GKA action. The success of dorzagliatin in the treatment of T2D has brought new hope for GK in setting a good model for repairing the underlying defects in the pancreatic islets and liver of T2D patients.展开更多
A chronic liver disease usually results in iron accumulation, and an excess of iron will further aggravate liver injury, forming a vicious circle. Likewise, it also plays a significant role in other organs when it com...A chronic liver disease usually results in iron accumulation, and an excess of iron will further aggravate liver injury, forming a vicious circle. Likewise, it also plays a significant role in other organs when it comes to iron metabolism. A long time passes between the time it takes to break through to MRIbased iron diagnosis and its ability to distinguish the types of iron accumulation accurately and quickly.This work highlighted a new type of iron accumulation treatment solution integrated with diagnosis and treatment. A chelating method for ICG and Leci that can assist PAI and MRI to achieve better diagnostic and therapeutic effects. This work revealed biomaterial engineering techniques are being adapted to address clinical medical problems through cutting-edge research.展开更多
Background:Interleukin-21(IL-21)has a regulatory effect on various immune cells.Its effect on macrophage function remains unclear.Aims:This study aimed to investigate the effect of IL-21 on the macrophagesmediated inf...Background:Interleukin-21(IL-21)has a regulatory effect on various immune cells.Its effect on macrophage function remains unclear.Aims:This study aimed to investigate the effect of IL-21 on the macrophagesmediated inflammatory response and explore its mechanism.Materials&Methods:Phorbol myristate acetate was used to induce THP-1-derived macrophages.Then,cells were stimulated with IL-21 and/or lipopolysaccharide(LPS).To determine the effect of IL-21 on the production of inflammatory factors in THP-1-derived macrophages,the messenger RNA(mRNA)and protein levels of IL-6,tumor necrosis factor-α(TNF-α),IL-8,and IL-10 were detected by real-time polymerase chain reaction(RT-PCR)and enzyme-linked immunosorbent assay(ELISA),respectively.Meanwhile,to explore the effect of IL-21 on macrophage polarization,macrophage phenotype,gene expression,and cytokine secretion mediated by THP-1-derived macrophage were detected by flow cytometry,RT-PCR,and ELISA.Results:First,we found that the IL-21 receptor was expressed in THP-1-derived macrophages.IL-21 enhanced LPS-mediated TNF-α,IL-6,and IL-10 production in THP-1-derived macrophages.During the polarization of THP-1-derived macrophages to M1-like macrophages,IL-21 induced the expression of macrophage surface markers CD86 and CD80,and related genes,such as TNF-α,IL-6,IL-1β,and DC-SIGN mRNA,inhibited Dectin-1 mRNA expression and promoted the secretion of TNF-α.During the polarization of THP-1-derived macrophages to M2-like macrophages,IL-21 enhanced the expression of macrophage surface markers CD86 and CD163,and related genes,such as TNF-α,IL-1β,IL-10,Dectin-1,and DC-SIGN mRNA,and promoted the secretion of IL-10.Conclusion:IL-21 promotes LPS-mediated production of inflammatory cytokines by THP-1-derived macrophages;IL-21 plays a two-way regulatory role in THP-1-derived macrophage polarization.展开更多
基金The authors would like to thank the editors and the anonymous reviewers for their helpful and constructive comments.This study was supported by National Key Technologies Research&Development Program(Grant No.2018YFC0808402)State Key Laboratory for GeoMechanics and Deep Underground Engineering,China University of Mining and Technology(Grant No.SKLGDUEK1824)the Fundamental Research Funds for the Central Universities(Grant No.FRF-TP-20-004A2).
文摘Rocks in underground works usually experience rather complex stress disturbance.For this,their fracture mechanism is significantly different from rocks subjected to conventional triaxial compression conditions.The effects of stress disturbances on rock geomechanical behaviors under fatigue loading conditions and triaxial unloading conditions have been reported in previous studies.However,little is known about the dependence of the unloading rate on fatigue loading and confining stress unloading(FL-CSU)conditions that influence rock failure.In this paper,we aimed at investigating the fracture behaviors of marble under FL-CSU conditions using the post-test X-ray computed tomography(CT)scanning technique and the GCTS RTR 2000 rock mechanics system.Results show that damage accumulation at the fatigue stage can influence the final fracture behaviors of marble.The stored elastic energy for rock samples under FL-CSU tests is relatively larger compared to those under conventional triaxial tests,and the dissipated energy used to drive damage evolution and crack propagation is larger for FL-CSU tests.In FL-CSU tests,as the unloading rate increases,the dissipated energy grows and elastic energy reduces.CT scanning after the test reveals the impacts of the unloading rate on the crack pattern and a fracture degree index is therein defined in this context to represent the crack dimension.It shows that the crack pattern after FL-CSU tests depends on the unloading rate,and the fracture degree is in agreement with the analysis of both the energy dissipation and the amount of energy released.The effect of unloading rate on fracture evolution characteristics of marble is revealed by a series of FL-CSU tests.
基金support from diverse funding sources,including the National Key Program for S&T Research and Development of the Ministry of Science and Technology(MOST),Yifang Wang's Science Studio of the Ten Thousand Talents Project,the CAS Key Foreign Cooperation Grant,the National Natural Science Foundation of China(NSFC)Beijing Municipal Science&Technology Commission,the CAS Focused Science Grant,the IHEP Innovation Grant,the CAS Lead Special Training Programthe CAS Center for Excellence in Particle Physics,the CAS International Partnership Program,and the CAS/SAFEA International Partnership Program for Creative Research Teams.
文摘The Circular Electron Positron Collider(CEPC)is a large scientific project initiated and hosted by China,fostered through extensive collaboration with international partners.The complex comprises four accelerators:a 30 GeV Linac,a 1.1 GeV Damping Ring,a Booster capable of achieving energies up to 180 GeV,and a Collider operating at varying energy modes(Z,W,H,and tt).The Linac and Damping Ring are situated on the surface,while the subterranean Booster and Collider are housed in a 100 km circumference underground tunnel,strategically accommodating future expansion with provisions for a potential Super Proton Proton Collider(SPPC).The CEPC primarily serves as a Higgs factory.In its baseline design with synchrotron radiation(SR)power of 30 MW per beam,it can achieve a luminosity of 5×10^(34)cm^(-2)s^(-1)per interaction point(IP),resulting in an integrated luminosity of 13 ab^(-1)for two IPs over a decade,producing 2.6 million Higgs bosons.Increasing the SR power to 50 MW per beam expands the CEPC's capability to generate 4.3 million Higgs bosons,facilitating precise measurements of Higgs coupling at sub-percent levels,exceeding the precision expected from the HL-LHC by an order of magnitude.This Technical Design Report(TDR)follows the Preliminary Conceptual Design Report(Pre-CDR,2015)and the Conceptual Design Report(CDR,2018),comprehensively detailing the machine's layout,performance metrics,physical design and analysis,technical systems design,R&D and prototyping efforts,and associated civil engineering aspects.Additionally,it includes a cost estimate and a preliminary construction timeline,establishing a framework for forthcoming engineering design phase and site selection procedures.Construction is anticipated to begin around 2027-2028,pending government approval,with an estimated duration of 8 years.The commencement of experiments and data collection could potentially be initiated in the mid-2030s.
基金supported by the National Key Research and Development Program of China (Grant Nos.2020YFC2201501,and 2021YFC2203004)supported by the National Natural Science Foundation of China (Grant Nos.12075041 and 12147102)+11 种基金supported by the National Natural Science Foundation of China (Grant No.12247147)the International Postdoctoral Exchange Fellowship Programthe Boya Postdoctoral Fellowship of Peking Universitysupported by the National Natural Science Foundation of China (Grant Nos.11963005,and 11603018)Yunnan Provincial Foundation (Grant Nos.2016FD006,and 2019FY003005)Reserved Talents for Young and Middle-aged Academic and Technical Leaders in Yunnan Province ProgramYunnan Provincial High level Talent Training Support Plan Youth Top Programthe National Natural Science Foundation of China (Grant No.11847301)the Fundamental Research Funds for the Central Universities (Grant No.2019CDJDWL0005)supported by Peking Uniersity (Grant No.7101302974)the National Natural Science Foundation of China (Grant Nos.12025507,and 12150015)the Key Research Program of Frontier Science of the Chinese Academy of Sciences (CAS) (Grant No.ZDBS-LY-7003)。
文摘We explore the possibility that domain wall networks generate the stochastic gravitational wave background(SGWB) observed as a strong common power-law process in the Data Release-2 of Parkes Pulsar Timing Array. We find that a broad range of parameters, specifically wall tension around σ_(DW)^(29-414 TeV)^(3) and wall-decay temperature within T_(d) ~ 20-257 MeV, can explain this phenomenon at a 68% credible level. Meanwhile, the same parameters could ease the Hubble tension if particles from these domain wall networks decay into dark radiation. We establish a direct analytical relationship, ΩGW(f_(p), T_(0))h^(2)~ Ω_(rad)h^(2)(Ω_νΩN_(eff))^(2),to illustrate this coincidence, underlining its importance in the underlying physics and potential applicability to a wider range of models and data. Conversely, if the common power-law process is not attributed to domain wall networks, our findings impose tight limits on the wall tension and decay temperature.
文摘Laser hot wire cladding, with the prominent features of low heat input, high energy efficiency, and high precision, is widely used for remanufacturing metal parts. The cladding process, however, needs to be improved by using a quantitative method. In this work, volumetric defect ratio was proposed as the criterion to describe the integrity of forming quality for cladding layers. Laser deposition experiments with FV520B, one of martensitic stainless steels, were designed by using the Taguchi method. Four process variables, namely, laser power （P）, scanning speed （Vs）, wire feed rate （Vf）, and wire current （/）, were optimized based on the analysis of signal-to-noise （S/N） ratio. Metallurgic observation of cladding layer was conducted to compare the forming quality and to validate the analysis method. A stable and continuous process with the optimum parameter combination produced uniform microstructure with minimal defects and cracks, which resulted in a good metallurgical bonding interface.
基金the National Natural Science Foundation of China(Grant Nos.11974058,61307050,and 61701271)the Beijing Nova Program(No.Z201100006820125)+2 种基金Beijing Municipal Science and Technology Commission,in part by the Beijing Natural Science Foundation(No.Z210004)the Shandong Natural Science Foundation(No.ZR2016AM27)the State Key Laboratory of Information Photonics and Optical Communications(No.IPOC2021ZT01),BUPT,China.
文摘Optical microcavities have the ability to confne photons in small mode volumes for long periods of time,greatly enhancing light-matter interactions,and have become one of the research hotspots in international academia.In recent years,sensing applications in complex environments have inspired the development of multimode optical microcavity sensors.These multimode sensors can be used not only for multi-parameter detection but also to improve measurement precision.In this review,we introduce multimode sensing methods based on optical microcavities and present an overview of the multimode single/multi-parameter optical microcavities sensors.Expected further research activities are also put forward.
基金This work was supported by the National Natural Science Foundation of China(Nos.61307050 and 61701271)the Natural Science Foundation of Shandong Province(No.ZR2016AM27)。
文摘In order to realize the ultrastrong absorption of graphene with electrical modulation properties, we designed a composite structure of graphene and parity-time(PT) symmetry photonic crystal, which is achieved by placing the graphene layer on the top layer of the PT symmetry photonic crystal. In this paper, the absorption properties of graphene and the electrical modulating properties of the structure were theoretically analyzed based on the transfer matrix method. The result shows that the proposed structure can achieve the absorption of 31.5 d B for the communication wavelength of 1550 nm;meanwhile,by setting the electric field intensity to ±0.02 V/nm, the absorption of graphene can be largely modulated to realize an electrically switchable effect, the modulation depth of graphene absorption can reach nearly 100%, and the operation speed is also close to 8.171 GHz. This investigation provides a novel approach to design graphene-based optoelectronic devices and optical communication devices.
基金supported by the grant from the National Natural Science Foundation of China(No.32241011).
文摘Glucokinase (GK) plays a pivotal role in glucose homeostasis as the glucose sensor in the pancreas and liver. Loss of function of GK results in hyperglycemia, and gain of function causes congenital hyperinsulinemic hypoglycemia. We speculate that the progressive loss of GK at both messenger RNA (mRNA) and protein levels in the islets and liver would be the key mechanism for Type 2 diabetes (T2D) pathogenesis. The development of GK activator (GKA) as an anti-diabetic drug has been endeavored for several decades. The failure of the early development of GKAs is due to the limitation of understanding the mode of GKA action. The success of dorzagliatin in the treatment of T2D has brought new hope for GK in setting a good model for repairing the underlying defects in the pancreatic islets and liver of T2D patients.
基金supported by the Major State Basic Research Development Program of China (No. 2017YFA0205201)the National Natural Science Foundation of China (Nos. 81925019 and U1705281)+2 种基金the Fundamental Research Funds for the Central Universities (Nos. 20720190088 and 20720200019)the China Postdoctoral Science Foundation (Nos. 2020TQ0181 and 2021M690096)the Program for New Century Excellent Talents in University, China (No. NCET-13-0502)。
文摘A chronic liver disease usually results in iron accumulation, and an excess of iron will further aggravate liver injury, forming a vicious circle. Likewise, it also plays a significant role in other organs when it comes to iron metabolism. A long time passes between the time it takes to break through to MRIbased iron diagnosis and its ability to distinguish the types of iron accumulation accurately and quickly.This work highlighted a new type of iron accumulation treatment solution integrated with diagnosis and treatment. A chelating method for ICG and Leci that can assist PAI and MRI to achieve better diagnostic and therapeutic effects. This work revealed biomaterial engineering techniques are being adapted to address clinical medical problems through cutting-edge research.
基金National Natural Science Foundation of China,Grant/Award Number:81571573。
文摘Background:Interleukin-21(IL-21)has a regulatory effect on various immune cells.Its effect on macrophage function remains unclear.Aims:This study aimed to investigate the effect of IL-21 on the macrophagesmediated inflammatory response and explore its mechanism.Materials&Methods:Phorbol myristate acetate was used to induce THP-1-derived macrophages.Then,cells were stimulated with IL-21 and/or lipopolysaccharide(LPS).To determine the effect of IL-21 on the production of inflammatory factors in THP-1-derived macrophages,the messenger RNA(mRNA)and protein levels of IL-6,tumor necrosis factor-α(TNF-α),IL-8,and IL-10 were detected by real-time polymerase chain reaction(RT-PCR)and enzyme-linked immunosorbent assay(ELISA),respectively.Meanwhile,to explore the effect of IL-21 on macrophage polarization,macrophage phenotype,gene expression,and cytokine secretion mediated by THP-1-derived macrophage were detected by flow cytometry,RT-PCR,and ELISA.Results:First,we found that the IL-21 receptor was expressed in THP-1-derived macrophages.IL-21 enhanced LPS-mediated TNF-α,IL-6,and IL-10 production in THP-1-derived macrophages.During the polarization of THP-1-derived macrophages to M1-like macrophages,IL-21 induced the expression of macrophage surface markers CD86 and CD80,and related genes,such as TNF-α,IL-6,IL-1β,and DC-SIGN mRNA,inhibited Dectin-1 mRNA expression and promoted the secretion of TNF-α.During the polarization of THP-1-derived macrophages to M2-like macrophages,IL-21 enhanced the expression of macrophage surface markers CD86 and CD163,and related genes,such as TNF-α,IL-1β,IL-10,Dectin-1,and DC-SIGN mRNA,and promoted the secretion of IL-10.Conclusion:IL-21 promotes LPS-mediated production of inflammatory cytokines by THP-1-derived macrophages;IL-21 plays a two-way regulatory role in THP-1-derived macrophage polarization.
