Fine structures of the crust and upper mantle of the basin-and-range juncture on the northwestern margin of the Qinghai-Tibetan Plateau are first delineated by the deep seismic reflection profile across the juncture z...Fine structures of the crust and upper mantle of the basin-and-range juncture on the northwestern margin of the Qinghai-Tibetan Plateau are first delineated by the deep seismic reflection profile across the juncture zone between the Tarim Basin and the West Kunlun Mountains. Evidence is found for the northward subduction of the northwest marginal lithosphere of the Qinghai-Tibetan Plateau and its collision with Tarim lithosphere beneath the West Kunlun Mountains. The lithosphere image of the face-to-face subduction and collision determines the coupling relationship between the Tarim Basin and the West Kunlun Mountains at the lithosphere scale and reflects the process of continent- continent collision.展开更多
A large number of in-situ volcanic reservoirs have been discovered from the Meso-Cenozoic rift basin group in eastern China.Based on drilling results in combination with geological and geophysical analysis,a case stud...A large number of in-situ volcanic reservoirs have been discovered from the Meso-Cenozoic rift basin group in eastern China.Based on drilling results in combination with geological and geophysical analysis,a case study from the Early Cretaceous Xujiaweizi fault-depression shows that the formation mechanism of in-situ volcanic reservoirs is characterized by"fault-controlled body,body-controlled facies,facies-controlled reservoir,and reservoir-controlled accumulation".In other words,deep faults control the volcanic eruption type,volcanic body,and gas reservoir distribution;the volcanic body determines the spatial distribution of volcanic facies and volcanic gas reservoir size;the volcanic facies control reservoir physical properties and effective thickness of gas formation;the volcanic reservoir properties control gas reservoir type and gas productivity.The result is useful to guiding the discovery of in-situ volcanic gas reservoirs in faulted basins in both theory and practice.展开更多
The deep seismic sounding profile across the Tianshan Mountains revealed a two-layer crustal structure in the Tianshan region, namely the lower and upper crusts. Lateral variations of layer velocity and thickness are ...The deep seismic sounding profile across the Tianshan Mountains revealed a two-layer crustal structure in the Tianshan region, namely the lower and upper crusts. Lateral variations of layer velocity and thickness are evidently shown. Low-velocity layers spread discontinuously at the bottom of the upper crust. The Mono depth is 47 km in the Kuytun area and 50 km in the Xayar area. In the Tianshan Mountains, the Moho becomes deeper with the maximum depth of 62 km around the boundary between the southern and northern Tianshan Mountains. The average velocity ranges from 6.1 to 6.3 km/s in the crust and 8.15 km/s at the top of the upper mantle. Two groups of reliable reflective seismic phases of the Moho (Pm1 and Pm2) are recognized on the shot record section of the Kuytun area. A staked and offset region, 20-30 km long, is displayed within a shot-geophone distance of 190-210 km in Pm1 and Pm2. Calculation shows that the Moho is offset by 10 km in the northern Tianshan region, 62 km deep in the south while展开更多
Inter-particle bonding is an important factor affecting the property of cold sprayed metallic deposit.Because the interface bonding between particles in deposit is directly determined by plastic strain of particles du...Inter-particle bonding is an important factor affecting the property of cold sprayed metallic deposit.Because the interface bonding between particles in deposit is directly determined by plastic strain of particles during spraying,Cu deposits were made at series of impact velocities of 578 m s^-1 to 745 m s^-1 and 807 m s^-1 to correlate particle impact condition with microstructure and properties of the deposits.Results show that as the average particle impact velocity increases from 578 m s^-1 to 745 m s^-1 and 807 m s^-1,the deposition efficiency of feedstock powder increases from 58%to 84%and even to 95%.Although all three deposits reveal dense microstructure due to the high ductility of Cu,the deformation degree of the deposited particles remarkably increases with increasing impact velocity.The enhanced plastic deformation of the deposited particles leads to more dispersed oxide scale and thereby stronger interparticle bonding with the strength of the deposit along the deposition direction increasing from 25.8 MPa to 148.5 MPa.The electrical and thermal conductivities at through-thickness direction of the deposit at particle impact velocity of 807 m s^-1 are 78%IACS,295 W m^-1 K^-1,respectively.展开更多
Based on deep geophysical detections, we have reconstructed the crustal structure from the eastern margin of the Tibetan Plateau to the Jiangnan-Xuefeng orogenic belt. The results suggest that the Yangtze Block was ov...Based on deep geophysical detections, we have reconstructed the crustal structure from the eastern margin of the Tibetan Plateau to the Jiangnan-Xuefeng orogenic belt. The results suggest that the Yangtze Block was overthrusted by crustal materials in its NW direction from the eastern Tibetan Plateau but in its SE direction from the Jiangnan orogen. These overthrusting effects control the crustal structure from the western Sichuan to the western area of the Jiangnan orogen-Xuefeng orogenic belt. The eastward extruded materials from the eastern Tibetan Plateau were blocked by the rigid basement in the Sichuan Basin, where upper-middle crust was overthrusted whereas the lower crust was underthrusted beneath the Sichuan Basin. The underthrusted unit was absorbed by crustal folding, shortening and thickening in the Yangtze Block, forming the Xiongpo and Longquan Mountains tectonic belts and resulting in the NW-directed thrusting of the Pujiang-Chengdu-Deyang fault, and the western hillsiden fault in the Longquan Mountain. These results provide resolution to the controversy where the eastward extrusion material from the Qinghai-Tibet Plateau had gone. Overall, that Yangtze Block was subjected to thrusting of the crustal materials from the orogenic belts over its both sides. This finding has implications for the study of the intracontinental orogenic mechanism in South China, the reconstruction of tectonic evolutionary history and the kinematics processes during the lateral extrusion of the Tibet Plateau.展开更多
The efficient non-noble metal-based bifunctional electrocatalyst for hydrogen evolution reaction(HER)and oxygen evolution reaction(OER)has attracted great interest,which is highly significant to enhance the efficiency...The efficient non-noble metal-based bifunctional electrocatalyst for hydrogen evolution reaction(HER)and oxygen evolution reaction(OER)has attracted great interest,which is highly significant to enhance the efficiency of hydrogen production from water electrolysis.Herein,inspired by the appropriate hydrogen adsorption free energy of transition metal alloy and the strong corrosion resistance of phosphide in alkaline electrolyte,carbon compound NiFeMo-P anchored on nickel foam(NiFeMo-P-C)is obtained by simple one-pot hydrothermal and subsequent hydrogen reduction treatment.Remarkably,the NiFeMo-P-C exhibits excellent bifunctional electrocatalytic performances toward HER and OER with low overpotentials of 87 and 196 mV at 10 mA·cm^(-2),respectively.Moreover,the electrolyzer using NiFeMo-P-C as both cathode and anode only requires a cell voltage of 1.50 V to reach a current density of 10 mA·cm^(-2),along with an outstanding long-term stability for 50 h.The synergistic effect among alloys and phosphide,partially broken hollow morphology and porous nickel foam substrate jointly impart NiFeMo-P-C high electrocatalytic activity and superior durability.展开更多
Mesenchymal stem cells (MSCs) are characterized by their multilineage potential and low immunogenicity.However,the properties of MSCs under pathological conditions are unclear.The current study investigated the differ...Mesenchymal stem cells (MSCs) are characterized by their multilineage potential and low immunogenicity.However,the properties of MSCs under pathological conditions are unclear.The current study investigated the differentiation potential and immunological characteristics of bone marrow-derived MSCs from ovariectomized-osteoporotic rats (OP-BMSCs).Although the expression of cell morphology-and sternness-related surface markers was similar between OP-BMSCs and BMSCs from healthy rats (H-BMSCs),the proliferation rate was significantly decreased compared with that of H-BMSCs.Regarding multilineage potential,osteogenesis and chondrogenesis abilities of OP-BMSCs decreased,but the adipogenesis ability was significantly enhanced compared with that of H-BMSCs.As expected,decreased osteogenesis following osteogenic induction resulted in reduced expression of p-catenin,osteocalcin,and runt-related transcription factor 2 in OP-BMSCs.Remarkably,the expression of the co-stimulatory proteins CD40 and CD80 was significantly higher,whereas the expression of the negative costimulatory molecule programmed cell death ligand 1 was significantly lower in the OP-BMSCs than that in H-BMSCs.Consequently,H-BMSCs inhibited the proliferation and secretion of inflammatory cytokines from anti-CD3 antibody-activated T cells,whereas OP-BMSCs did not.These results indicate that decreased osteogenesis and increased immunogenicity of OPBMSCs contribute to bone loss in osteoporosis.展开更多
The access divide was once the basic form of the digital divide.The development of Internet infrastructure has narrowed the access divide and increased application coverage,but it has also touched off a connectivity d...The access divide was once the basic form of the digital divide.The development of Internet infrastructure has narrowed the access divide and increased application coverage,but it has also touched off a connectivity dividend difference.Taking the online market as an example,we examine the sources of the dividend difference and the factors influencing it with in a connectivity framework.We found that the narrowing of the access divide has resulted in enhanced connectivity and platform development,giving people the chance to benefit from transforming the various assets in which they have previously invested into differentiated compound connectivity capital.In the course,the scale and rate of the conversion are affected by two multiplier effects and especially by online platforms.The process is ultimately expressed in the dividend difference.展开更多
In-situ polymerized electrolytes significantly enhance the interfacial compatibility of lithium metal batteries(LMBs). Typically,in-situ polymerized 1,3-dioxolane(PDOL) exhibits low interfacial resistance, yet still s...In-situ polymerized electrolytes significantly enhance the interfacial compatibility of lithium metal batteries(LMBs). Typically,in-situ polymerized 1,3-dioxolane(PDOL) exhibits low interfacial resistance, yet still suffers from low ionic conductivity and a narrow electrochemical stability window(ESW). Here, an ultra-stable PDOL-based polymer electrolyte is developed by incorporating plasticizers of tetramethylene sulfone(TMS) and fluorinated ethylene carbonate(FEC) into the 3D cross-linked network, achieving a significant enhancement in the transport capacity and efficiency of Li-ion. The ionic conductivity reaches3.63×10^(-4)S cm^(-1)even at room temperature, and the transference number(tLi^(+)) is even higher at 0.85. Furthermore, the ESW of this electrolyte can be increased to 4.5 V with the addition of TMS, which forms a thin and robust antioxidant cathode-electrolyte interface(CEI) on the surface of high-voltage LiCoO_(2). FEC generates an inorganic-rich solid-electrolyte interface(SEI) on the Li anode, which effectively inhibits the growth of lithium dendrites. Benefiting from the aforementioned advantages, the highvoltage lithium metal battery demonstrates outstanding long-cycle stability, with 93.2% capacity retention after 200 cycles. This work offers a straightforward and accessible method for the practical implementation of high energy density in-situ polymerized solid-state LMBs.展开更多
Upon the osteoporotic condition,sluggish osteogenesis,excessive bone resorption,and chronic inflammation make the osseointegration of bioinert titanium(Ti)implants with surrounding bone tissues difficult,often lead to...Upon the osteoporotic condition,sluggish osteogenesis,excessive bone resorption,and chronic inflammation make the osseointegration of bioinert titanium(Ti)implants with surrounding bone tissues difficult,often lead to prosthesis loosening,bone collapse,and implant failure.In this study,we firstly designed clickable mussel-inspired peptides(DOPA-N3)and grafted them onto the surfaces of Ti materials through robust catechol-TiO2 coordinative interactions.Then,two dibenzylcyclooctyne(DBCO)-capped bioactive peptides RGD and BMP-2 bioactive domain(BMP-2)were clicked onto the DOPA-N3-coated Ti material surfaces via bio-orthogonal reaction.We characterized the surface morphology and biocompatibility of the Ti substrates and optimized the osteogenic capacity of Ti surfaces through adjusting the ideal ratios of BMP-2/RGD at 3:1.In vitro,the dual-functionalized Ti substrates exhibited excellent promotion on adhesion and osteogenesis of mesenchymal stem cells(MSCs),and conspicuous immunopolarization-regulation to shift macrophages to alternative(M2)phenotypes and inhibit inflammation,as well as enhancement of osseointegration and mechanical stability in osteoporotic rats.In summary,our biomimetic surface modification strategy by bio-orthogonal reaction provided a convenient and feasible method to resolve the bioinertia and clinical complications of Ti-based implants,which was conducive to the long-term success of Ti implants,especially in the osteoporotic or inflammatory conditions.展开更多
The oxide scale present on the feedstock particles is critical for inter-particle bond formation in the cold spray(CS)coating process,therefore,oxide scale break-up is a prerequisite for clean metallic contact which g...The oxide scale present on the feedstock particles is critical for inter-particle bond formation in the cold spray(CS)coating process,therefore,oxide scale break-up is a prerequisite for clean metallic contact which greatly improves the quality of inter-particle bonding within the deposited coating.In general,a spray powder which contains a thicker oxide scale on its surface(i.e.,powders having high oxygen content)requires a higher critical particle velocity for coating formation,which also lowers the deposition efficiency(DE)making the whole process a challenging task.In this work,it is reported for the first time that an artificially oxidized copper(Cu)powder containing a high oxygen content of 0.81 wt.%with a thick surface oxide scale of 0.71μm.,can help achieve an astonishing increment in DE.A transition of surficial oxide scale evolution starting with crack initiations followed by segmenting to peeling-off was observed during the high velocity particle impact of the particles,which helps in achieving an astounding increment in DE.Single-particle deposit observations revealed that the thick oxide scale peels off from most of the sprayed powder surfaces during the high-velocity impact,which leaves a clean metallic surface on the deposited particle.This makes the successive particles to bond easily and thus leads to a higher DE.Further,owning to the peeling-off of the oxide scale from the feedstock particles,very few discontinuous oxide scale segments are retained at inter-particle boundaries ensuring a high electrical conductivity within the resulting deposit.Dependency of the oxide scale threshold thickness for peeling-off during the high velocity particle impact was also investigated.展开更多
Background This investigation was undertaken to obtain differentially expressed genes related to human glioma using cDNA microarray and the characterization of one novel full-length gene. Methods Total RNA was extract...Background This investigation was undertaken to obtain differentially expressed genes related to human glioma using cDNA microarray and the characterization of one novel full-length gene. Methods Total RNA was extracted from human glioma tissues and normal brain tissues, and mRNA was used to make probes. After hybridization and washing, the results were scanned using a computer system. The gene named 681F05 clone was an expressed gene to human glioma through four-time hybridization and scanning. Subsequently northern blot analysis was performed by northern blot, 5’RACE and bioinformatics. Results Fifteen differentially expressed genes to human glioma were obtained through four-time hybridization and scanning. Northern blot analysis confirmed that 681F05 clone was low-expressed in human brain tissues and over-expressed in human glioma tissues. The analysis of BLASTn and BLASTx showed that 681F05 clone is two cDNA clones encoding two novel proteins that are highly identified to the cyclophilin isoform 10 of C. Elgans, respectively. Sequence analysis revealed the two cDNA clones are two different splicing variants of a novel cycophilin-like gene (PPIL3a and PPIL3b).Conclusions cDNA microarray technology can be successfully used to identify differentially expressed genes. The novel full-length gene of human PPIL3 may be correlated with the formation of human glioma.展开更多
Converting carbon dioxide(CO2)into value-added chemicals by CO2 reduction has been considered as a potential way to solve the current energy crisis and environmental problem.Among the methods of CO2 reduction,the elec...Converting carbon dioxide(CO2)into value-added chemicals by CO2 reduction has been considered as a potential way to solve the current energy crisis and environmental problem.Among the methods of CO2 reduction,the electrochemical method has been widely used due to its mild reaction condition and high reaction efficiency.In the electrochemical reduction system,the CO2 electrocatalyst is the most important part.Although many CO2 electrocatalysts have been developed,efficient catalysts with high activity,selectivity and stability are still lacking.Copper sulfide compound,as a low-toxicity and emerging material,has broad prospects in the field of CO2 reduction due to its unique structural and electrochemical properties.Much progress has been achieved with copper sulfide nanocrystalline and the field is rapidly developing.This paper summarizes the preparation,recent progress in development,and factors affecting the electrocatalytic CO2 reduction performance with copper sulfide compound as a catalyst.Prospects for future development are also outlined,with the aim of using copper sulfide compound as a highly active and stable electrocatalyst for CO2 reduction.展开更多
The Square Kilometre Array(SKA)project consists of delivering two largest radio telescope arrays being built by the SKA Observatory(SKAO),which is an intergovernmental organization bringing together nations from aroun...The Square Kilometre Array(SKA)project consists of delivering two largest radio telescope arrays being built by the SKA Observatory(SKAO),which is an intergovernmental organization bringing together nations from around the world with China being one of the major member countries.The computing resources needed to process,distribute,curate and use the vast amount of data that will be generated by the SKA telescopes are too large for the SKAO to manage on its own.To address this challenge,the SKAO is working with the international community to create a shared,distributed data,computing and networking capability called the SKA Regional Centre Alliance.In this model,the SKAO will be supported by a global network of SKA Regional Centres(SRCs)distributed around the world in its member countries to build an end-to-end science data system that will provide astronomers with high-quality science products.SRCs undertake deep processing,scientific analysis,and long-term storage of the SKA data,as well as user support.China has been actively participating in and promoting the construction of SRCs.This paper introduces the international cooperation and ongoing prototyping of the global SRC network,the basis for the construction of the China SRC and describes in detail the progress of the China SRC prototype.The paper also presents examples of scientific applications of SKA precursor and pathfinder telescopes performed using resources from the China SRC prototype.Finally,the future prospects of the China SRC are presented.展开更多
The Northeastern Tibetan plateau records Caledonian Qilian orogeny and Cenozoic reactivation by continental collision between the Indian and Asian plates. In order to provide the constraint on the Qilian orogenic mech...The Northeastern Tibetan plateau records Caledonian Qilian orogeny and Cenozoic reactivation by continental collision between the Indian and Asian plates. In order to provide the constraint on the Qilian orogenic mechanism and the expansion of the plateau,wide-angle seismic data was acquired along a 430 km-long profile between Jingtai and Hezuo. There is strong height variation along the profile,which is dealt by topography flattening scheme in our crustal velocity structure reconstruction. We herein present the upper crustal P-wave velocity structure model resulting from the interpretation of first arrival dataset from topography-dependent eikonal traveltime tomography. With topography flattening scheme to process real topography along the profile,the evenness of ray coverage times of the image area（upper crust）is improved,which provides upper crustal velocity model comparable to the classic traveltime tomography（with model expansion scheme to process irregular surface）. The upper crustal velocity model shows zoning character which matcheswith the tectonic division of the Qaidam-Kunlun-West Qinling belt,the Central and Northern Qilian,and the Alax blocks along the profile. The resultant upper crustal P-wave velocity model is expected to provide important base for linkage between the mapped surface geology and deep structure or geodynamics in Northeastern Tibet.展开更多
Persistent asymptomatic(PA)SARS-CoV-2 infections have been identified.The immune responses in these patients are unclear,and the development of effective treatments for these patients is needed.Here,we report a cohort...Persistent asymptomatic(PA)SARS-CoV-2 infections have been identified.The immune responses in these patients are unclear,and the development of effective treatments for these patients is needed.Here,we report a cohort of 23 PA cases carrying viral RNA for up to 191 days.PA cases displayed low levels of inflammatory and interferon response,weak antibody response,diminished circulating follicular helper T cells(cTfh),and inadequate specific CD4+and CD8+T-cell responses during infection,which is distinct from symptomatic infections and resembling impaired immune activation.Administration of a single dose of Ad5-nCoV vaccine to 10 of these PA cases elicited rapid and robust antibody responses as well as coordinated B-cell and cTfh responses,resulting in successful viral clearance.Vaccine-induced antibodies were able to neutralize various variants of concern and persisted for over 6 months,indicating long-term protection.Therefore,our study provides an insight into the immune status of PA infections and highlights vaccination as a potential treatment for prolonged SARS-CoV-2 infections.展开更多
Purpose: To determine the distribution of the toxin among individual muscles after intramuscular injection of botulinum toxin gel.Methods: One eye of 7 New Zealand white rabbits was randomized into group A, and the co...Purpose: To determine the distribution of the toxin among individual muscles after intramuscular injection of botulinum toxin gel.Methods: One eye of 7 New Zealand white rabbits was randomized into group A, and the contralateral eye was into group B. Eyes in group A received medial rectus intramuscular injection of 2.5 IU of 125I-BTX-A gel in 0.1 ml, and those in group B received equivalent amount of 125I-BTX-A solution by medial rectus intramuscular injection. Four rectus muscles and the levator palpebrae superioris were harvested and the radioactivity of muscles was measured 16 hours after the injection.Results: In group A, the radioactivity of per gram medial rectus was significantly higher than that of other muscles (P ＜ 0.01), and there was no statistically significant difference in the radioactivity of per gram muscles among other muscles (P ＞ 0.05). In group B, the radioactivity of per gram medial rectus and levator palpebrae superioris was significantly higher than that of other muscles respectively(P ＜ 0.05), and the difference in the radioactivity of per gram muscles between medial rectus and levator palpebrae superioris was not statistically significant (P ＞ 0.05). The radioactivity of per gram medial rectus in group A was higher than that in group B (t=3.731 ,P=0.01), and there was no significant difference in the radioactivity of per gram muscles among other homonymous muscles (P ＞ 0.05).Conclusion: The toxin dispersed principally in the injected muscle and the local concentration of the toxin was much high following intramuscular injection of botulinum toxin gel.展开更多
Cell sheet-based scaffold-free technology holds promise for tissue engineering applications and has been extensively explored during the past decades.However,efficient harvest and handling of cell sheets remain challe...Cell sheet-based scaffold-free technology holds promise for tissue engineering applications and has been extensively explored during the past decades.However,efficient harvest and handling of cell sheets remain challenging,including insufficient extracellular matrix content and poor mechanical strength.Mechanical loading has been widely used to enhance extracellular matrix production in a variety of cell types.However,currently,there are no effective ways to apply mechanical loading to cell sheets.In this study,we prepared thermo-responsive elastomer substrates by grafting poly(N-isopropyl acrylamide)(PNIPAAm)to poly(dimethylsiloxane)(PDMS)surfaces.The effect of PNIPAAm grafting yields on cell behaviours was investigated to optimize surfaces suitable for cell sheet culturing and harvesting.Subsequently,MC3T3-E1 cells were cultured on the PDMS-g-PNIPAAm substrates under mechanical stimulation by cyclically stretching the substrates.Upon maturation,the cell sheets were harvested by lowering the temperature.We found that the extracellular matrix content and thickness of cell sheet were markedly elevated upon appropriate mechanical conditioning.Reverse transcription quantitative polymerase chain reaction and Western blot analyses further confirmed that the expression of osteogenic-specific genes and major matrix components were up-regulated.After implantation into the critical-sized calvarial defects of mice,the mechanically conditioned cell sheets significantly promoted new bone formation.Findings from this study reveal that thermo-responsive elastomer,together with mechanical conditioning,can potentially be applied to prepare high-quality cell sheets for bone tissue engineering.展开更多
Astronomy is the oldest natural science based on observation,and a census of objects in the sky map to create a catalog is the basis for further research.This effort is achieved through astronomical object detection,a...Astronomy is the oldest natural science based on observation,and a census of objects in the sky map to create a catalog is the basis for further research.This effort is achieved through astronomical object detection,also known as"source finding",which aims to identify individual objects in an astronomical image and then retrieve the properties of those objects to form a catalog.The completeness,reliability,and accuracy of the resulting catalog has a profound impact on astrophysical research.展开更多
The consensus problem for fractional multi-agent systems(MASs)with time delay is considered.The distributed fractional proportional-integral(PI)-type controller is designed so that the consensus of the proposed system...The consensus problem for fractional multi-agent systems(MASs)with time delay is considered.The distributed fractional proportional-integral(PI)-type controller is designed so that the consensus of the proposed systems is achieved.Moreover,explicit condition to determine the crossing directions is developed.The results show that with the increase of time delay,the closed-loop system has two different dynamic characteristics:From consensus to nonconsensus and consensus switching.Furthermore,delay margin within which consensus of MASs will always hold is determined.The results should provide useful guidelines in the consensus analysis and in the analytical design of the distributed controllers.展开更多
文摘Fine structures of the crust and upper mantle of the basin-and-range juncture on the northwestern margin of the Qinghai-Tibetan Plateau are first delineated by the deep seismic reflection profile across the juncture zone between the Tarim Basin and the West Kunlun Mountains. Evidence is found for the northward subduction of the northwest marginal lithosphere of the Qinghai-Tibetan Plateau and its collision with Tarim lithosphere beneath the West Kunlun Mountains. The lithosphere image of the face-to-face subduction and collision determines the coupling relationship between the Tarim Basin and the West Kunlun Mountains at the lithosphere scale and reflects the process of continent- continent collision.
基金supported by the National Basic Research Program of China(Grant No.2009CB219308)
文摘A large number of in-situ volcanic reservoirs have been discovered from the Meso-Cenozoic rift basin group in eastern China.Based on drilling results in combination with geological and geophysical analysis,a case study from the Early Cretaceous Xujiaweizi fault-depression shows that the formation mechanism of in-situ volcanic reservoirs is characterized by"fault-controlled body,body-controlled facies,facies-controlled reservoir,and reservoir-controlled accumulation".In other words,deep faults control the volcanic eruption type,volcanic body,and gas reservoir distribution;the volcanic body determines the spatial distribution of volcanic facies and volcanic gas reservoir size;the volcanic facies control reservoir physical properties and effective thickness of gas formation;the volcanic reservoir properties control gas reservoir type and gas productivity.The result is useful to guiding the discovery of in-situ volcanic gas reservoirs in faulted basins in both theory and practice.
文摘The deep seismic sounding profile across the Tianshan Mountains revealed a two-layer crustal structure in the Tianshan region, namely the lower and upper crusts. Lateral variations of layer velocity and thickness are evidently shown. Low-velocity layers spread discontinuously at the bottom of the upper crust. The Mono depth is 47 km in the Kuytun area and 50 km in the Xayar area. In the Tianshan Mountains, the Moho becomes deeper with the maximum depth of 62 km around the boundary between the southern and northern Tianshan Mountains. The average velocity ranges from 6.1 to 6.3 km/s in the crust and 8.15 km/s at the top of the upper mantle. Two groups of reliable reflective seismic phases of the Moho (Pm1 and Pm2) are recognized on the shot record section of the Kuytun area. A staked and offset region, 20-30 km long, is displayed within a shot-geophone distance of 190-210 km in Pm1 and Pm2. Calculation shows that the Moho is offset by 10 km in the northern Tianshan region, 62 km deep in the south while
基金financially supported by the National Nature Science Foundation of China(Grant Nos.51875443 and 51401158)the Shaanxi Co-Innovation Projects(Grant No.2015KTTSGY03-03)the Fund from The Key Lab of Guangdong for Modern Surface Engineering Technology and the Shaanxi Natural Science Foundation(Grant No.2015JQ5200).
文摘Inter-particle bonding is an important factor affecting the property of cold sprayed metallic deposit.Because the interface bonding between particles in deposit is directly determined by plastic strain of particles during spraying,Cu deposits were made at series of impact velocities of 578 m s^-1 to 745 m s^-1 and 807 m s^-1 to correlate particle impact condition with microstructure and properties of the deposits.Results show that as the average particle impact velocity increases from 578 m s^-1 to 745 m s^-1 and 807 m s^-1,the deposition efficiency of feedstock powder increases from 58%to 84%and even to 95%.Although all three deposits reveal dense microstructure due to the high ductility of Cu,the deformation degree of the deposited particles remarkably increases with increasing impact velocity.The enhanced plastic deformation of the deposited particles leads to more dispersed oxide scale and thereby stronger interparticle bonding with the strength of the deposit along the deposition direction increasing from 25.8 MPa to 148.5 MPa.The electrical and thermal conductivities at through-thickness direction of the deposit at particle impact velocity of 807 m s^-1 are 78%IACS,295 W m^-1 K^-1,respectively.
基金supported by the National Natural Science Foundation of China(Grant Nos.41574093,41774114)SinoProbe-02(Grant No.A1011B)
文摘Based on deep geophysical detections, we have reconstructed the crustal structure from the eastern margin of the Tibetan Plateau to the Jiangnan-Xuefeng orogenic belt. The results suggest that the Yangtze Block was overthrusted by crustal materials in its NW direction from the eastern Tibetan Plateau but in its SE direction from the Jiangnan orogen. These overthrusting effects control the crustal structure from the western Sichuan to the western area of the Jiangnan orogen-Xuefeng orogenic belt. The eastward extruded materials from the eastern Tibetan Plateau were blocked by the rigid basement in the Sichuan Basin, where upper-middle crust was overthrusted whereas the lower crust was underthrusted beneath the Sichuan Basin. The underthrusted unit was absorbed by crustal folding, shortening and thickening in the Yangtze Block, forming the Xiongpo and Longquan Mountains tectonic belts and resulting in the NW-directed thrusting of the Pujiang-Chengdu-Deyang fault, and the western hillsiden fault in the Longquan Mountain. These results provide resolution to the controversy where the eastward extrusion material from the Qinghai-Tibet Plateau had gone. Overall, that Yangtze Block was subjected to thrusting of the crustal materials from the orogenic belts over its both sides. This finding has implications for the study of the intracontinental orogenic mechanism in South China, the reconstruction of tectonic evolutionary history and the kinematics processes during the lateral extrusion of the Tibet Plateau.
基金The authors are grateful to the National Natural Science Foundation of China(No.51871247).
文摘The efficient non-noble metal-based bifunctional electrocatalyst for hydrogen evolution reaction(HER)and oxygen evolution reaction(OER)has attracted great interest,which is highly significant to enhance the efficiency of hydrogen production from water electrolysis.Herein,inspired by the appropriate hydrogen adsorption free energy of transition metal alloy and the strong corrosion resistance of phosphide in alkaline electrolyte,carbon compound NiFeMo-P anchored on nickel foam(NiFeMo-P-C)is obtained by simple one-pot hydrothermal and subsequent hydrogen reduction treatment.Remarkably,the NiFeMo-P-C exhibits excellent bifunctional electrocatalytic performances toward HER and OER with low overpotentials of 87 and 196 mV at 10 mA·cm^(-2),respectively.Moreover,the electrolyzer using NiFeMo-P-C as both cathode and anode only requires a cell voltage of 1.50 V to reach a current density of 10 mA·cm^(-2),along with an outstanding long-term stability for 50 h.The synergistic effect among alloys and phosphide,partially broken hollow morphology and porous nickel foam substrate jointly impart NiFeMo-P-C high electrocatalytic activity and superior durability.
基金This work was partially supported by the Natural Science Foundation of China(91432302,31620103905,81501179)the Human Connectome Project,WU-Minn Consortium(Principal Investigators:David Van Essen and Kamil Ugurbil1U54MH091657)funded by the 16 NIH Institutes and Centers that support the NIH Blueprint for Neuroscience Research.
文摘Mesenchymal stem cells (MSCs) are characterized by their multilineage potential and low immunogenicity.However,the properties of MSCs under pathological conditions are unclear.The current study investigated the differentiation potential and immunological characteristics of bone marrow-derived MSCs from ovariectomized-osteoporotic rats (OP-BMSCs).Although the expression of cell morphology-and sternness-related surface markers was similar between OP-BMSCs and BMSCs from healthy rats (H-BMSCs),the proliferation rate was significantly decreased compared with that of H-BMSCs.Regarding multilineage potential,osteogenesis and chondrogenesis abilities of OP-BMSCs decreased,but the adipogenesis ability was significantly enhanced compared with that of H-BMSCs.As expected,decreased osteogenesis following osteogenic induction resulted in reduced expression of p-catenin,osteocalcin,and runt-related transcription factor 2 in OP-BMSCs.Remarkably,the expression of the co-stimulatory proteins CD40 and CD80 was significantly higher,whereas the expression of the negative costimulatory molecule programmed cell death ligand 1 was significantly lower in the OP-BMSCs than that in H-BMSCs.Consequently,H-BMSCs inhibited the proliferation and secretion of inflammatory cytokines from anti-CD3 antibody-activated T cells,whereas OP-BMSCs did not.These results indicate that decreased osteogenesis and increased immunogenicity of OPBMSCs contribute to bone loss in osteoporosis.
文摘The access divide was once the basic form of the digital divide.The development of Internet infrastructure has narrowed the access divide and increased application coverage,but it has also touched off a connectivity dividend difference.Taking the online market as an example,we examine the sources of the dividend difference and the factors influencing it with in a connectivity framework.We found that the narrowing of the access divide has resulted in enhanced connectivity and platform development,giving people the chance to benefit from transforming the various assets in which they have previously invested into differentiated compound connectivity capital.In the course,the scale and rate of the conversion are affected by two multiplier effects and especially by online platforms.The process is ultimately expressed in the dividend difference.
基金supported by the National Natural Science Foundation of China (52202327)Science and Technology Commission of Shanghai Municipality (22ZR1471300)。
文摘In-situ polymerized electrolytes significantly enhance the interfacial compatibility of lithium metal batteries(LMBs). Typically,in-situ polymerized 1,3-dioxolane(PDOL) exhibits low interfacial resistance, yet still suffers from low ionic conductivity and a narrow electrochemical stability window(ESW). Here, an ultra-stable PDOL-based polymer electrolyte is developed by incorporating plasticizers of tetramethylene sulfone(TMS) and fluorinated ethylene carbonate(FEC) into the 3D cross-linked network, achieving a significant enhancement in the transport capacity and efficiency of Li-ion. The ionic conductivity reaches3.63×10^(-4)S cm^(-1)even at room temperature, and the transference number(tLi^(+)) is even higher at 0.85. Furthermore, the ESW of this electrolyte can be increased to 4.5 V with the addition of TMS, which forms a thin and robust antioxidant cathode-electrolyte interface(CEI) on the surface of high-voltage LiCoO_(2). FEC generates an inorganic-rich solid-electrolyte interface(SEI) on the Li anode, which effectively inhibits the growth of lithium dendrites. Benefiting from the aforementioned advantages, the highvoltage lithium metal battery demonstrates outstanding long-cycle stability, with 93.2% capacity retention after 200 cycles. This work offers a straightforward and accessible method for the practical implementation of high energy density in-situ polymerized solid-state LMBs.
基金This work was supported by the National Key Research and Development Program of China(2019YFA0112000)the National Natural Science Foundation of China(81972059,81772358,21875092)+1 种基金the key R&D programs of Jiangsu Province(BE2019668),China Postdoctoral Science Foundation(2020M671587)Jiangsu Provincial Clinical Orthopedic Center,Priority Academic Program Development of Jiangsu Higher Education Institutions(PAPD),the High-level Talents Research and Development Program of Affiliated Dongguan Hospital,Southern Medical University(K202102).
文摘Upon the osteoporotic condition,sluggish osteogenesis,excessive bone resorption,and chronic inflammation make the osseointegration of bioinert titanium(Ti)implants with surrounding bone tissues difficult,often lead to prosthesis loosening,bone collapse,and implant failure.In this study,we firstly designed clickable mussel-inspired peptides(DOPA-N3)and grafted them onto the surfaces of Ti materials through robust catechol-TiO2 coordinative interactions.Then,two dibenzylcyclooctyne(DBCO)-capped bioactive peptides RGD and BMP-2 bioactive domain(BMP-2)were clicked onto the DOPA-N3-coated Ti material surfaces via bio-orthogonal reaction.We characterized the surface morphology and biocompatibility of the Ti substrates and optimized the osteogenic capacity of Ti surfaces through adjusting the ideal ratios of BMP-2/RGD at 3:1.In vitro,the dual-functionalized Ti substrates exhibited excellent promotion on adhesion and osteogenesis of mesenchymal stem cells(MSCs),and conspicuous immunopolarization-regulation to shift macrophages to alternative(M2)phenotypes and inhibit inflammation,as well as enhancement of osseointegration and mechanical stability in osteoporotic rats.In summary,our biomimetic surface modification strategy by bio-orthogonal reaction provided a convenient and feasible method to resolve the bioinertia and clinical complications of Ti-based implants,which was conducive to the long-term success of Ti implants,especially in the osteoporotic or inflammatory conditions.
基金supported financially by the National Natural Science Foundation of China(No.51875443)the Guangdong Basic and Applied Basic Research Foundation(Nos.2019B1515120016 and 202002030290)+3 种基金the Shaanxi Co-Innovation Projects(No.2015KTTSGY03-03)the Shaanxi Natural Science Foundation(No.2015JQ5200)the Open Project from The Key Lab of Guangdong for Modern Surface Engineering Technologyfinancial support by Guangdong Academy of Sciences’Project of Constructing First-class Domestic Research Institutions(Nos.2019GDASYL-0503006,2020GDASYL-20200302011)。
文摘The oxide scale present on the feedstock particles is critical for inter-particle bond formation in the cold spray(CS)coating process,therefore,oxide scale break-up is a prerequisite for clean metallic contact which greatly improves the quality of inter-particle bonding within the deposited coating.In general,a spray powder which contains a thicker oxide scale on its surface(i.e.,powders having high oxygen content)requires a higher critical particle velocity for coating formation,which also lowers the deposition efficiency(DE)making the whole process a challenging task.In this work,it is reported for the first time that an artificially oxidized copper(Cu)powder containing a high oxygen content of 0.81 wt.%with a thick surface oxide scale of 0.71μm.,can help achieve an astonishing increment in DE.A transition of surficial oxide scale evolution starting with crack initiations followed by segmenting to peeling-off was observed during the high velocity particle impact of the particles,which helps in achieving an astounding increment in DE.Single-particle deposit observations revealed that the thick oxide scale peels off from most of the sprayed powder surfaces during the high-velocity impact,which leaves a clean metallic surface on the deposited particle.This makes the successive particles to bond easily and thus leads to a higher DE.Further,owning to the peeling-off of the oxide scale from the feedstock particles,very few discontinuous oxide scale segments are retained at inter-particle boundaries ensuring a high electrical conductivity within the resulting deposit.Dependency of the oxide scale threshold thickness for peeling-off during the high velocity particle impact was also investigated.
文摘Background This investigation was undertaken to obtain differentially expressed genes related to human glioma using cDNA microarray and the characterization of one novel full-length gene. Methods Total RNA was extracted from human glioma tissues and normal brain tissues, and mRNA was used to make probes. After hybridization and washing, the results were scanned using a computer system. The gene named 681F05 clone was an expressed gene to human glioma through four-time hybridization and scanning. Subsequently northern blot analysis was performed by northern blot, 5’RACE and bioinformatics. Results Fifteen differentially expressed genes to human glioma were obtained through four-time hybridization and scanning. Northern blot analysis confirmed that 681F05 clone was low-expressed in human brain tissues and over-expressed in human glioma tissues. The analysis of BLASTn and BLASTx showed that 681F05 clone is two cDNA clones encoding two novel proteins that are highly identified to the cyclophilin isoform 10 of C. Elgans, respectively. Sequence analysis revealed the two cDNA clones are two different splicing variants of a novel cycophilin-like gene (PPIL3a and PPIL3b).Conclusions cDNA microarray technology can be successfully used to identify differentially expressed genes. The novel full-length gene of human PPIL3 may be correlated with the formation of human glioma.
基金the National Postdoctoral Program for Innovative Talents of China,Postdoctoral Science Foundation of China(Grant No.2018M640759)Natural Science Foundation of China(Grant No.21872174 and U1932148)+4 种基金Project of Innovation-Driven Plan in Central South University(Grant No.20180018050001)State Key Laboratory of Powder Metallurgy,International Science and Technology Cooperation Program(Grant No.2017YFE0127800)Hunan Provincial Science and Technology Program(2017XK2026)Shenzhen Science and Technology Innovation Project(Grant No.JCYJ20180307151313532)Thousand Youth Talents Plan of China and Hundred Youth Talents Program of Hunan.
文摘Converting carbon dioxide(CO2)into value-added chemicals by CO2 reduction has been considered as a potential way to solve the current energy crisis and environmental problem.Among the methods of CO2 reduction,the electrochemical method has been widely used due to its mild reaction condition and high reaction efficiency.In the electrochemical reduction system,the CO2 electrocatalyst is the most important part.Although many CO2 electrocatalysts have been developed,efficient catalysts with high activity,selectivity and stability are still lacking.Copper sulfide compound,as a low-toxicity and emerging material,has broad prospects in the field of CO2 reduction due to its unique structural and electrochemical properties.Much progress has been achieved with copper sulfide nanocrystalline and the field is rapidly developing.This paper summarizes the preparation,recent progress in development,and factors affecting the electrocatalytic CO2 reduction performance with copper sulfide compound as a catalyst.Prospects for future development are also outlined,with the aim of using copper sulfide compound as a highly active and stable electrocatalyst for CO2 reduction.
基金supported by the National Key R&D Program of China(Grant No.2018YFA0404603)Chinese Academy of Sciences International Partner Program(Grant No.114231KYSB20170003)+2 种基金National Natural Science Foundation of China(Grant No.12041301)Youth Innovation Promotion AssociationChinese Academy of Sciences(Grant Nos.201664,and2021258)。
文摘The Square Kilometre Array(SKA)project consists of delivering two largest radio telescope arrays being built by the SKA Observatory(SKAO),which is an intergovernmental organization bringing together nations from around the world with China being one of the major member countries.The computing resources needed to process,distribute,curate and use the vast amount of data that will be generated by the SKA telescopes are too large for the SKAO to manage on its own.To address this challenge,the SKAO is working with the international community to create a shared,distributed data,computing and networking capability called the SKA Regional Centre Alliance.In this model,the SKAO will be supported by a global network of SKA Regional Centres(SRCs)distributed around the world in its member countries to build an end-to-end science data system that will provide astronomers with high-quality science products.SRCs undertake deep processing,scientific analysis,and long-term storage of the SKA data,as well as user support.China has been actively participating in and promoting the construction of SRCs.This paper introduces the international cooperation and ongoing prototyping of the global SRC network,the basis for the construction of the China SRC and describes in detail the progress of the China SRC prototype.The paper also presents examples of scientific applications of SKA precursor and pathfinder telescopes performed using resources from the China SRC prototype.Finally,the future prospects of the China SRC are presented.
基金financial support for this work by the Ministry of Science and Technology of China (2011CB808904)the Ministry of Land and Resources of China (SinoProbe-02-02 or 201011041,SinoProbe-03-02 or 201011047)the National Nature Science Foundation of China (41174075,41021063,41274090 and 41174043)
文摘The Northeastern Tibetan plateau records Caledonian Qilian orogeny and Cenozoic reactivation by continental collision between the Indian and Asian plates. In order to provide the constraint on the Qilian orogenic mechanism and the expansion of the plateau,wide-angle seismic data was acquired along a 430 km-long profile between Jingtai and Hezuo. There is strong height variation along the profile,which is dealt by topography flattening scheme in our crustal velocity structure reconstruction. We herein present the upper crustal P-wave velocity structure model resulting from the interpretation of first arrival dataset from topography-dependent eikonal traveltime tomography. With topography flattening scheme to process real topography along the profile,the evenness of ray coverage times of the image area（upper crust）is improved,which provides upper crustal velocity model comparable to the classic traveltime tomography（with model expansion scheme to process irregular surface）. The upper crustal velocity model shows zoning character which matcheswith the tectonic division of the Qaidam-Kunlun-West Qinling belt,the Central and Northern Qilian,and the Alax blocks along the profile. The resultant upper crustal P-wave velocity model is expected to provide important base for linkage between the mapped surface geology and deep structure or geodynamics in Northeastern Tibet.
基金the National Key R&D Program of China(2021YFC2302004 and 2021YFC2301102)National Natural Science Foundation of China(82172240,82101836,81901623 and 82201933)+6 种基金China National Postdoctoral Program for Innovative Talents(BX2021087),China Postdoctoral Science Foundation(2021M690787 and 2022M710892)Guangdong Basic and Applied Basic Research Foundation(2021B1515130005 and 2022B1515020059)Guangdong Medical Technology Research Foundation(B2022233)Guangzhou Science and Technology Planning Program Municipal School/Institute-Joint Funded Program(202102010143)PhD Startup Foundation from Guangzhou Women and Children’s Medical Center(2018-2020)State Key Laboratory of Respiratory Diseases Funded Program(SKLRD-Z-202330)Zhong Nanshan Medical Foundation of Guangdong Province(ZNSA-202001,ZNSXS-2020012,ZNSA-2020013 and ZNSXS-20220015).
文摘Persistent asymptomatic(PA)SARS-CoV-2 infections have been identified.The immune responses in these patients are unclear,and the development of effective treatments for these patients is needed.Here,we report a cohort of 23 PA cases carrying viral RNA for up to 191 days.PA cases displayed low levels of inflammatory and interferon response,weak antibody response,diminished circulating follicular helper T cells(cTfh),and inadequate specific CD4+and CD8+T-cell responses during infection,which is distinct from symptomatic infections and resembling impaired immune activation.Administration of a single dose of Ad5-nCoV vaccine to 10 of these PA cases elicited rapid and robust antibody responses as well as coordinated B-cell and cTfh responses,resulting in successful viral clearance.Vaccine-induced antibodies were able to neutralize various variants of concern and persisted for over 6 months,indicating long-term protection.Therefore,our study provides an insight into the immune status of PA infections and highlights vaccination as a potential treatment for prolonged SARS-CoV-2 infections.
文摘Purpose: To determine the distribution of the toxin among individual muscles after intramuscular injection of botulinum toxin gel.Methods: One eye of 7 New Zealand white rabbits was randomized into group A, and the contralateral eye was into group B. Eyes in group A received medial rectus intramuscular injection of 2.5 IU of 125I-BTX-A gel in 0.1 ml, and those in group B received equivalent amount of 125I-BTX-A solution by medial rectus intramuscular injection. Four rectus muscles and the levator palpebrae superioris were harvested and the radioactivity of muscles was measured 16 hours after the injection.Results: In group A, the radioactivity of per gram medial rectus was significantly higher than that of other muscles (P ＜ 0.01), and there was no statistically significant difference in the radioactivity of per gram muscles among other muscles (P ＞ 0.05). In group B, the radioactivity of per gram medial rectus and levator palpebrae superioris was significantly higher than that of other muscles respectively(P ＜ 0.05), and the difference in the radioactivity of per gram muscles between medial rectus and levator palpebrae superioris was not statistically significant (P ＞ 0.05). The radioactivity of per gram medial rectus in group A was higher than that in group B (t=3.731 ,P=0.01), and there was no significant difference in the radioactivity of per gram muscles among other homonymous muscles (P ＞ 0.05).Conclusion: The toxin dispersed principally in the injected muscle and the local concentration of the toxin was much high following intramuscular injection of botulinum toxin gel.
基金National Natural Science Foundation of China(No.81925027)Priority Academic Program Development of Jiangsu Higher Education Institutions.
文摘Cell sheet-based scaffold-free technology holds promise for tissue engineering applications and has been extensively explored during the past decades.However,efficient harvest and handling of cell sheets remain challenging,including insufficient extracellular matrix content and poor mechanical strength.Mechanical loading has been widely used to enhance extracellular matrix production in a variety of cell types.However,currently,there are no effective ways to apply mechanical loading to cell sheets.In this study,we prepared thermo-responsive elastomer substrates by grafting poly(N-isopropyl acrylamide)(PNIPAAm)to poly(dimethylsiloxane)(PDMS)surfaces.The effect of PNIPAAm grafting yields on cell behaviours was investigated to optimize surfaces suitable for cell sheet culturing and harvesting.Subsequently,MC3T3-E1 cells were cultured on the PDMS-g-PNIPAAm substrates under mechanical stimulation by cyclically stretching the substrates.Upon maturation,the cell sheets were harvested by lowering the temperature.We found that the extracellular matrix content and thickness of cell sheet were markedly elevated upon appropriate mechanical conditioning.Reverse transcription quantitative polymerase chain reaction and Western blot analyses further confirmed that the expression of osteogenic-specific genes and major matrix components were up-regulated.After implantation into the critical-sized calvarial defects of mice,the mechanically conditioned cell sheets significantly promoted new bone formation.Findings from this study reveal that thermo-responsive elastomer,together with mechanical conditioning,can potentially be applied to prepare high-quality cell sheets for bone tissue engineering.
基金the National Key R&D Program of China(2018YFA0404603)the International Partnership Program of Chinese Academy of Sciences(114231KYSB20170003)the Youth Association for Promoting Innovation。
文摘Astronomy is the oldest natural science based on observation,and a census of objects in the sky map to create a catalog is the basis for further research.This effort is achieved through astronomical object detection,also known as"source finding",which aims to identify individual objects in an astronomical image and then retrieve the properties of those objects to form a catalog.The completeness,reliability,and accuracy of the resulting catalog has a profound impact on astrophysical research.
基金supported in part by the National Natural Science Foundation of China under Grant Nos.61773207,62173183the Natural Science Fund for Distinguished Young Scholars of Jiangsu Province under Grant No.BK20190020.
文摘The consensus problem for fractional multi-agent systems(MASs)with time delay is considered.The distributed fractional proportional-integral(PI)-type controller is designed so that the consensus of the proposed systems is achieved.Moreover,explicit condition to determine the crossing directions is developed.The results show that with the increase of time delay,the closed-loop system has two different dynamic characteristics:From consensus to nonconsensus and consensus switching.Furthermore,delay margin within which consensus of MASs will always hold is determined.The results should provide useful guidelines in the consensus analysis and in the analytical design of the distributed controllers.
