A recently discovered family of kagome lattice materials,AV_(3)Sb_(5)(A=K,Rb,Cs),has attracted great interest,especiallyin the debate over their dominant superconducting pairing symmetry.To explore this issue,we study...A recently discovered family of kagome lattice materials,AV_(3)Sb_(5)(A=K,Rb,Cs),has attracted great interest,especiallyin the debate over their dominant superconducting pairing symmetry.To explore this issue,we study the superconductingpairing behavior within the kagome-lattice Hubbard model through the constrained path Monte Carlo method.It isfound that doping around the Dirac point generates a dominant next-nearest-neighbor-d pairing symmetry driven by on-siteCoulomb interaction U.However,when considering the nearest-neighbor interaction V,it may induce nearest-neighbor-ppairing to become the preferred pairing symmetry.Our results provide useful information to identify the dominant superconductingpairing symmetry in the AV_(3)Sb_(5)family.展开更多
By utilizing the fluctuation exchange approximation method,we perform a study on the superconducting pairing symmetry in a t_(2g) three-orbital model on the square lattice.Although the tight-binding parameters of the ...By utilizing the fluctuation exchange approximation method,we perform a study on the superconducting pairing symmetry in a t_(2g) three-orbital model on the square lattice.Although the tight-binding parameters of the model are based on Sr_(2)RuO_(4),we have systematically studied the evolution of superconducting pairing symmetry with the carrier density and interactions,making our findings relevant to a broader range of material systems.Under a moderate Hund’s coupling,we find that spin fluctuations dominate the superconducting pairing,leading to a prevalent spin-singlet pairing with a d_(x^(2)-y^(2))-wave symmetry for the carrier density within the range of n=1.5-4 per site.By reducing the Hund’s coupling,the charge fluctuations are enhanced and play a crucial role in determining the pairing symmetry,leading to a transition of the pairing symmetry from the spin-singlet d_(x^(2)-y^(2))-wave to the spin-triplet p-wave.Furthermore,we find that the superconducting pairings are orbital dependent.As the carrier density changes from n=4 to n=1.5,the active orbitals for superconducting pairing shift from the quasi-two-dimensional orbital dxy to the quasi-one-dimensional orbitals d_(xz) and d_(yz).展开更多
Using the Skyrme density functional theory,potential energy surfaces of^(240)Pu with constraints on the axial quadrupole and octupole deformations(q_(20)and q_(30))were calculated.The volume-like and surface-like pair...Using the Skyrme density functional theory,potential energy surfaces of^(240)Pu with constraints on the axial quadrupole and octupole deformations(q_(20)and q_(30))were calculated.The volume-like and surface-like pairing forces,as well as a combination of these two forces,were used for the Hartree–Fock–Bogoliubov approximation.Variations in the least-energy fission path,fission barrier,pairing energy,total kinetic energy,scission line,and mass distribution of the fission fragments based on the different forms of the pairing forces were analyzed and discussed.The fission dynamics were studied based on the timedependent generator coordinate method plus the Gaussian overlap approximation.The results demonstrated a sensitivity of the mass and charge distributions of the fission fragments on the form of the pairing force.Based on the investigation of the neutron-induced fission of^(239)Pu,among the volume,mixed,and surface pairing forces,the mixed pairing force presented a good reproduction of the experimental data.展开更多
Recent experimental findings have demonstrated the occurrence of superconductivity in Bernal bilayer graphene when induced by a magnetic field.In this study,we conduct a theoretical investigation of the potential pair...Recent experimental findings have demonstrated the occurrence of superconductivity in Bernal bilayer graphene when induced by a magnetic field.In this study,we conduct a theoretical investigation of the potential pairing symmetry within this superconducting system.By developing a theoretical model,we primarily calculate the free energy of the system with p+ip-wave parallel spin pairing,p+ip-wave anti-parallel spin pairing and d+i d-wave pairing symmetry.Our results confirm that the magnetic field is indeed essential for generating the superconductivity.We discover that the p+ip-wave parallel spin pairing leads to a lower free energy for the system.The numerical calculations of the energy band structure,zero-energy spectral function and density of states for each of the three pairing symmetries under consideration show a strong consistency with the free energy results.展开更多
We study theoretically the electrical shot noise properties of tunnel junctions between a normal metal and a superconductor with the mixture of singlet s-wave and chiral triplet p-wave pairing due to broken inversion ...We study theoretically the electrical shot noise properties of tunnel junctions between a normal metal and a superconductor with the mixture of singlet s-wave and chiral triplet p-wave pairing due to broken inversion symmetry. We investigate how the shot noise properties vary as the relative amplitude between the two parity components in the pairing potential is changed. It is demonstrated that some characteristics of the electrical shot noise properties of such tunnel junctions may depend sensitively on the relative amplitude between the two parity components in the pairing potential, and some significant changes may occur in the electrical shot noise properties when the relative amplitude between the two parity components is varied from the singlet s-wave pairing dominated regime to the chiral triplet p-wave pairing dominated regime. In the chiral triplet p-wave pairing dominated regime, the ratio of noise power to electric current is close to 2e both in the in-gap and in the out-gap region. In the singlet s-wave pairing dominated regime, the value of this ratio is close to 4e in the inner gap region but may reduce to about 2e in the outer gap region as the relative amplitude of the chiral triplet pairing component is increased. The variations of the differential shot noise with the bias voltage also exhibit some significantly different features in different regimes. Such different features can serve as useful diagnostic tools for the determination of the relative magnitude of the two parity components in the pairing potential.展开更多
In the new era,there is an urgent need to further promote pairing assistance to Tibet,promote the simultaneous construction of a strong agriculture in Tibet and the China's Mainland,and compose a Chinese-style mod...In the new era,there is an urgent need to further promote pairing assistance to Tibet,promote the simultaneous construction of a strong agriculture in Tibet and the China's Mainland,and compose a Chinese-style modernization.Southern Tibet,located in the southeastern part of the Tibet Autonomous Region,includes Shannan City and Nyingchi City,is a region assisted by four provincial partners including Hubei Province.This paper introduces the agricultural environment in southern Tibet,studies its agricultural characteristics,and analyzes the main issues of its pairing assistance.Taking forging the strong consciousness of the Chinese national community as the main line,the paper explores strategies for promoting agricultural high-quality development in southern Tibet through pairing assistance to Tibet from the perspective of agricultural power,and proposes some strategies,such as inheriting agricultural cultural heritage,promoting the upgrading of modern seed industry,enhancing the characteristic advantages of highland barley(naked barley)and animal husbandry industries,and developing edible fungi and cold water fish industries.展开更多
In this article,a comprehensive study of the fission process of Th,U,Pu,and Cm isotopes using a Yukawa-folded meanfield plus standard pairing model is presented.The study focused on analyzing the effects of the pairin...In this article,a comprehensive study of the fission process of Th,U,Pu,and Cm isotopes using a Yukawa-folded meanfield plus standard pairing model is presented.The study focused on analyzing the effects of the pairing interaction on the fragment mass distribution and its dependence on nuclear elongation.The significant role of pairing interactions in the fragment mass distributions of^(230)Th,^(234)U,^(240)Pu,and^(246)Cm was demonstrated.Numerical analysis revealed that increasing the pairing interaction strength decreased the asymmetric fragment mass distribution and increased the symmetric distribution.Furthermore,the odd-even mass differences at symmetric and asymmetric fission points were examined,highlighting their sensitivity to changes in the pairing interaction strength.Systematic analysis of the Th,U,Pu,and Cm isotope fragment mass distributions demonstrated the effectiveness of the model in reproducing the experimental data.In addition,the effects of the zero-point energy and half-width parameter on the fragment mass distribution for^(240)Pu were explored.Thus,this study provides valuable insights into the fission process by emphasizing the importance of pairing interactions and their relationship with nuclear elongation.展开更多
Autopolyploidy and allopolyploidy may represent an evolutionary advantage and are more common in plants than assumed. However, less attention has been paid to autopolyploidy than to allopolyploidy,and its evolutionary...Autopolyploidy and allopolyploidy may represent an evolutionary advantage and are more common in plants than assumed. However, less attention has been paid to autopolyploidy than to allopolyploidy,and its evolutionary consequences are largely unclear, especially for plants with high ploidy levels. In this study, we developed oligonucleotide(oligo)-based chromosome painting probes to identify individual chromosomes in S. spontaneum. Using fluorescence in situ hybridization(FISH), we investigated chromosome behavior during pachytene, metaphase, anaphase, and telophase of meiosis I(MI) in autotetraploid,autooctoploid, and autodecaploid S. spontaneum clones. All autopolyploid clones showed stable diploidized chromosome behavior;so that homologous chromosomes formed almost exclusively bivalents during MI. Two copies of homologous chromosome 8 with similar sizes in the autotetraploid clone showed preferential pairing with each other with respect to the other copies. However, sequence variation analysis showed no apparent differences among homologs of chromosome 8 and all other chromosomes. We suggest that either the stable diploidized pairing or the preferential pairing between homologous copies of chromosome 8 in the studied autopolyploid sugarcane are accounted for by unknown mechanisms other than DNA sequence similarity. Our results reveal evolutionary consequences of stable meiotic behavior in autopolyploid plants.展开更多
Wide hybridization is a strategy for broadening the genetic basis of wheat. Because an efficient method for inducing wheat–alien chromosome translocations will allow producing useful germplasm, it is desirable to dis...Wide hybridization is a strategy for broadening the genetic basis of wheat. Because an efficient method for inducing wheat–alien chromosome translocations will allow producing useful germplasm, it is desirable to discover new genes that induce chromosomal variation. In this study, chromosome 5P from A.cristatum was shown to induce many types of chromosomal structural variation in a common wheat background, including nonhomoeologous chromosome translocations, as revealed by genomic in situ hybridization, fluorescence in situ hybridization, and DNA marker analysis. Aberrant meiosis was associated with chromosomal structural variation, and aberrant meiotic behavior was observed in wheat–A.cristatum 5P monosomic and disomic addition lines, suggesting that the effect of chromosome 5P was independent of the number of chromosome 5P copies. Chromosome 5P disturbed homologous chromosome pairing at pachytene stage in a common wheat background, resulting in a high frequency of univalent formation and reduced crossing over. Thirteen genes involved in DNA repair or chromatin remodeling, including RAD52-like and MSH6 genes, were differentially expressed(upregulated) in wheat–A. cristatum 5P addition lines according to transcriptome analysis, implicating chromosome 5P in the process of meiotic double-strand break repair. These findings provide a new, efficient tool for inducing wheat–alien chromosome translocations and producing new germplasm.展开更多
Isotope effect on superconductive transition temperature(T_c)is an essential indicator to examine whether the mechanism of superconductors is conventional.Unconventional isotope effect of BiS_(2)-based superconductors...Isotope effect on superconductive transition temperature(T_c)is an essential indicator to examine whether the mechanism of superconductors is conventional.Unconventional isotope effect of BiS_(2)-based superconductors has been previously reported in ambient-pressure tetragonal phase.However,to comprehensively ascertain the nature of superconductivity,the investigation of BiS_(2)-based system in high-pressure structure is highly desirable.In this work,we carried out the first-principles calculations of phonon spectra and superconductivity in high-pressure monoclinic phase of LaO_(0.5)F_(0.5)BiS_(2)with ^(32)S and ^(34)S,and observed that the corresponding isotope coefficient is 0.13≤α≤0.20.This value is much greater than that of BiS_(2)-based superconductors in ambient-pressure phase,but slightly smaller than that of conventional MgB_2.Taking into account the calculated T_(c) lower than experimental results,we finally conclude that the moderate phonon-mediated pairing plays a significant role in forming superconductivity of BiS_(2)-based system in high-pressure phase,moreover,the cooperative multiple paring interactions should also be considered.展开更多
The combined lines having both phKL and Ph2-deficiency were obtained in the genetic background of common wheat (Triticum aestivum L.) landrace. These lines had normal fertility. In the wheat combined lines X Aegilops ...The combined lines having both phKL and Ph2-deficiency were obtained in the genetic background of common wheat (Triticum aestivum L.) landrace. These lines had normal fertility. In the wheat combined lines X Aegilops variabilis Eig. (or rye), a significant increase in the chiasmata of homoeologous pairing was shown by the phKL+Ph2(-) plants with respect to their phKL+Ph2 sibs, which indicates that Ph2-deficiency and phKL showed an additive effect on promoting pairing. The effects were shown in the increment of rod bivalents, ring bivalents and trivalents and reduction of univalents, of which, reduction of univalents was mainly due to the increment of rod bivalents. The combined lines are probably more desirable materials for alien gene transferring than phKL or Ph2(-) lines alone. In comparison with that of ph1b X Ae. variabilis (or rye), phKL+Ph2(-) X Ae. variabilis (or rye) show higher (or similar) numbers of rod bivalents, while the total chromosome pairing level significantly reduced that ascribed to the decrement in ring bivalents and multivalents. These results probably indicate the different genetic mechanisms for Ph1 and Ph2 or phKL on controlling homoeologous pairing.展开更多
Objective:To reveal the molecular mechanism underlying the compatibility of Salvia miltiorrhiza Bge(S.miltiorrhiza,Dan Shen)and C.tinctorius L.(C.tinctorius,Hong Hua)as an herb pair through network pharmacology and su...Objective:To reveal the molecular mechanism underlying the compatibility of Salvia miltiorrhiza Bge(S.miltiorrhiza,Dan Shen)and C.tinctorius L.(C.tinctorius,Hong Hua)as an herb pair through network pharmacology and subsequent experimental validation.Methods:Network pharmacology was applied to construct an active ingredient-efficacy target-disease protein network to reveal the unique regulation pattern of s.miltiorrhiza and C.tinctorius as herb pair.Molecular docking was used to verify the binding of the components of these herbs and their potential targets.An H9c2 glucose hypoxia model was used to evaluate the efficacy of the components and their synergistic effects,which were evaluated using the combination index.Western blot was performed to detect the protein expression of these targets.Results:Network pharmacology analysis revealed 5 pathways and 8 core targets of s.miltiorrhiza and C.tinctorius in myocardial protection.Five of the core targets were enriched in the hypoxia-inducible factor-1(HIF-1)signaling pathway.S.miltiorrhiza-C.tinctorius achieved vascular tone mainly by regulating the target genes of the HIF-1 pathway.As an upstream gene of the HIF-1 pathway,STAT3 can be activated by the active ingredients cryptotanshinone(Ctan),salvianolic acid B(Sal.B),and myricetin(Myric).Cell experiments revealed that Myric,Sal.B,and Ctan also exhibited synergistic myocardial protective activity.Molecular docking verified the strong binding of Myric,Sal.B,and Ctan to STAT3.Western blot further showed that the active ingredients synergistically upregulated the protein expressionof STAT3.Conclusion:The pharmacodynamic transmission analysis revealed that the active ingredients of S.miltiorrhiza and C.tinctorius can synergistically resist ischemia through various targets and pathways.This study provides a methodological reference for interpreting traditional Chinese medicine compatibility.展开更多
This review provides a comprehensive overview of current research on the structural,electronic,and magnetic characteristics of the recently discovered high-temperature superconductor La_(3)Ni_(2)O_(7) under high press...This review provides a comprehensive overview of current research on the structural,electronic,and magnetic characteristics of the recently discovered high-temperature superconductor La_(3)Ni_(2)O_(7) under high pressures.We present the experimental results for synthesizing and characterizing this material,derived from measurements of transport,thermodynamics,and various spectroscopic techniques,and discuss their physical implications.We also explore theoretical models proposed to describe the electronic structures and superconducting pairing symmetry in La_(3)Ni_(2)O_(7),highlighting the intricate interplay between electronic correlations and magnetic interactions.Despite these advances,challenges remain in growing high-quality samples free of extrinsic phases and oxygen deficiencies and in developing reliable measurement tools for determining diamagnetism and other physical quantities under high pressures.Further investigations in these areas are essential to deepening our understanding of the physical properties of La_(3)Ni_(2)O_(7) and unlocking its superconducting pairing mechanism.展开更多
To improve the reliable performance of information transmission in cooperative relay networks, the scheme of the max-rate spatial channel pairing (SCP) based on maximum ratio combining (MRC) is proposed. The schem...To improve the reliable performance of information transmission in cooperative relay networks, the scheme of the max-rate spatial channel pairing (SCP) based on maximum ratio combining (MRC) is proposed. The scheme includes three steps: channel phase cancellation, MRC, and SCP. Eventually, the solution of the scheme is modeled as convex optimization. The objective function of the optimization problem is to maximize the transmission rate and the optimization variable is the strategy of pairing between the uplink spatial sub-channels of each user and the corresponding downlink spatial ones. The theorem of the arrangement inequalities is adopted to obtain the approximate closed-form solution of the optimal pairing for this convex optimization. Simulation results demonstrate that compared to the existing distributed space-time block coding and coherent combined schemes without SCP, the proposed max-rate SCP plus MRC algorithm achieves appreciable improvements in symbol error rate in medium and high signal-to-noise ratio regimes. The achievable performance gain is due to the use of maxrate SCP.展开更多
Electrochemical co-reduction of nitrate(NO_(3)^(-))and carbon dioxide(CO_(2))has been widely regarded as a promising route to produce urea under ambient conditions,however the yield rate of urea has remained limited.H...Electrochemical co-reduction of nitrate(NO_(3)^(-))and carbon dioxide(CO_(2))has been widely regarded as a promising route to produce urea under ambient conditions,however the yield rate of urea has remained limited.Here,we report an atomically ordered intermetallic pallium-zinc(PdZn)electrocatalyst comprising a high density of PdZn pairs for boosting urea electrosynthesis.It is found that Pd and Zn are responsible for the adsorption and activation of NO_(3)^(-)and CO_(2),respectively,and thus the co-adsorption and co-activation NO_(3)^(-)and CO_(2) are achieved in ordered PdZn pairs.More importantly,the ordered and well-defined PdZn pairs provide a dual-site geometric structure conducive to the key C-N coupling with a low kinetical barrier,as demonstrated on both operando measurements and theoretical calculations.Consequently,the PdZn electrocatalyst displays excellent performance for the co-reduction to generate urea with a maximum urea Faradaic efficiency of 62.78%and a urea yield rate of 1274.42μg mg^(-1) h^(-1),and the latter is 1.5-fold larger than disordered pairs in PdZn alloys.This work paves new pathways to boost urea electrosynthesis via constructing ordered dual-metal pairs.展开更多
Implementing a new energy-saving electrochemical synthesis system with high commercial value is a strategy of the sustainable development for upgrading the bulk chemicals preparation technology in the future.Here,we r...Implementing a new energy-saving electrochemical synthesis system with high commercial value is a strategy of the sustainable development for upgrading the bulk chemicals preparation technology in the future.Here,we report a multiple redox-mediated linear paired electrolysis system,combining the hydrogen peroxide mediated cathode process with the I2 mediated anode process,and realize the conversion of furfural to furoic acid in both side of the dividedflow cell simultaneously.By reasonably controlling the cathode potential,the undesired water splitting reaction and furfural reduction side reactions are avoided.Under the galvanostatic electrolysis,the two-mediated electrode processes have good compatibility,which reduce the energy consumption by about 22%while improving the electronic efficiency by about 125%.This system provides a green electrochemical synthesis route with commercial prospects.展开更多
The prevalence of smartphones is deeply embedded in modern society,impacting various aspects of our lives.Their versatility and functionalities have fundamentally changed how we communicate,work,seek entertainment,and...The prevalence of smartphones is deeply embedded in modern society,impacting various aspects of our lives.Their versatility and functionalities have fundamentally changed how we communicate,work,seek entertainment,and access information.Among the many smartphones available,those operating on the Android platform dominate,being the most widely used type.This widespread adoption of the Android OS has significantly contributed to increased malware attacks targeting the Android ecosystem in recent years.Therefore,there is an urgent need to develop new methods for detecting Android malware.The literature contains numerous works related to Android malware detection.As far as our understanding extends,we are the first ones to identify dangerous combinations of permissions and system calls to uncover malicious behavior in Android applications.We introduce a novel methodology that pairs permissions and system calls to distinguish between benign and malicious samples.This approach combines the advantages of static and dynamic analysis,offering a more comprehensive understanding of an application’s behavior.We establish covalent bonds between permissions and system calls to assess their combined impact.We introduce a novel technique to determine these pairs’Covalent Bond Strength Score.Each pair is assigned two scores,one for malicious behavior and another for benign behavior.These scores serve as the basis for classifying applications as benign or malicious.By correlating permissions with system calls,the study enables a detailed examination of how an app utilizes its requested permissions,aiding in differentiating legitimate and potentially harmful actions.This comprehensive analysis provides a robust framework for Android malware detection,marking a significant contribution to the field.The results of our experiments demonstrate a remarkable overall accuracy of 97.5%,surpassing various state-of-the-art detection techniques proposed in the current literature.展开更多
基金supported by Beijing Natural Science Foundation(Grant No.1242022).The numerical simulations in this work were performed at HSCC of Beijing Normal University.
文摘A recently discovered family of kagome lattice materials,AV_(3)Sb_(5)(A=K,Rb,Cs),has attracted great interest,especiallyin the debate over their dominant superconducting pairing symmetry.To explore this issue,we study the superconductingpairing behavior within the kagome-lattice Hubbard model through the constrained path Monte Carlo method.It isfound that doping around the Dirac point generates a dominant next-nearest-neighbor-d pairing symmetry driven by on-siteCoulomb interaction U.However,when considering the nearest-neighbor interaction V,it may induce nearest-neighbor-ppairing to become the preferred pairing symmetry.Our results provide useful information to identify the dominant superconductingpairing symmetry in the AV_(3)Sb_(5)family.
基金Project supported by the National Key Research and Development Program of China (Grant No.2021YFA1400400)the National Natural Science Foundation of China (Grant Nos.92165205,12074175,and 12374137)。
文摘By utilizing the fluctuation exchange approximation method,we perform a study on the superconducting pairing symmetry in a t_(2g) three-orbital model on the square lattice.Although the tight-binding parameters of the model are based on Sr_(2)RuO_(4),we have systematically studied the evolution of superconducting pairing symmetry with the carrier density and interactions,making our findings relevant to a broader range of material systems.Under a moderate Hund’s coupling,we find that spin fluctuations dominate the superconducting pairing,leading to a prevalent spin-singlet pairing with a d_(x^(2)-y^(2))-wave symmetry for the carrier density within the range of n=1.5-4 per site.By reducing the Hund’s coupling,the charge fluctuations are enhanced and play a crucial role in determining the pairing symmetry,leading to a transition of the pairing symmetry from the spin-singlet d_(x^(2)-y^(2))-wave to the spin-triplet p-wave.Furthermore,we find that the superconducting pairings are orbital dependent.As the carrier density changes from n=4 to n=1.5,the active orbitals for superconducting pairing shift from the quasi-two-dimensional orbital dxy to the quasi-one-dimensional orbitals d_(xz) and d_(yz).
基金supported by the National Key R&D Program of China(No.2022YFA1602000)National Natural Science Foundation of China(Nos.12275081,U2067205,11790325,and U1732138)the Continuous-support Basic Scientific Research Project。
文摘Using the Skyrme density functional theory,potential energy surfaces of^(240)Pu with constraints on the axial quadrupole and octupole deformations(q_(20)and q_(30))were calculated.The volume-like and surface-like pairing forces,as well as a combination of these two forces,were used for the Hartree–Fock–Bogoliubov approximation.Variations in the least-energy fission path,fission barrier,pairing energy,total kinetic energy,scission line,and mass distribution of the fission fragments based on the different forms of the pairing forces were analyzed and discussed.The fission dynamics were studied based on the timedependent generator coordinate method plus the Gaussian overlap approximation.The results demonstrated a sensitivity of the mass and charge distributions of the fission fragments on the form of the pairing force.Based on the investigation of the neutron-induced fission of^(239)Pu,among the volume,mixed,and surface pairing forces,the mixed pairing force presented a good reproduction of the experimental data.
基金Project supported by the National Natural Science Foundation of China (Grant No.12074130)the Natural Science Foundation of Guangdong Province (Grant No.2021A1515012340)。
文摘Recent experimental findings have demonstrated the occurrence of superconductivity in Bernal bilayer graphene when induced by a magnetic field.In this study,we conduct a theoretical investigation of the potential pairing symmetry within this superconducting system.By developing a theoretical model,we primarily calculate the free energy of the system with p+ip-wave parallel spin pairing,p+ip-wave anti-parallel spin pairing and d+i d-wave pairing symmetry.Our results confirm that the magnetic field is indeed essential for generating the superconductivity.We discover that the p+ip-wave parallel spin pairing leads to a lower free energy for the system.The numerical calculations of the energy band structure,zero-energy spectral function and density of states for each of the three pairing symmetries under consideration show a strong consistency with the free energy results.
文摘We study theoretically the electrical shot noise properties of tunnel junctions between a normal metal and a superconductor with the mixture of singlet s-wave and chiral triplet p-wave pairing due to broken inversion symmetry. We investigate how the shot noise properties vary as the relative amplitude between the two parity components in the pairing potential is changed. It is demonstrated that some characteristics of the electrical shot noise properties of such tunnel junctions may depend sensitively on the relative amplitude between the two parity components in the pairing potential, and some significant changes may occur in the electrical shot noise properties when the relative amplitude between the two parity components is varied from the singlet s-wave pairing dominated regime to the chiral triplet p-wave pairing dominated regime. In the chiral triplet p-wave pairing dominated regime, the ratio of noise power to electric current is close to 2e both in the in-gap and in the out-gap region. In the singlet s-wave pairing dominated regime, the value of this ratio is close to 4e in the inner gap region but may reduce to about 2e in the outer gap region as the relative amplitude of the chiral triplet pairing component is increased. The variations of the differential shot noise with the bias voltage also exhibit some significantly different features in different regimes. Such different features can serve as useful diagnostic tools for the determination of the relative magnitude of the two parity components in the pairing potential.
基金Supported by the Project of National Social Science Foundation of China(22CMZ015).
文摘In the new era,there is an urgent need to further promote pairing assistance to Tibet,promote the simultaneous construction of a strong agriculture in Tibet and the China's Mainland,and compose a Chinese-style modernization.Southern Tibet,located in the southeastern part of the Tibet Autonomous Region,includes Shannan City and Nyingchi City,is a region assisted by four provincial partners including Hubei Province.This paper introduces the agricultural environment in southern Tibet,studies its agricultural characteristics,and analyzes the main issues of its pairing assistance.Taking forging the strong consciousness of the Chinese national community as the main line,the paper explores strategies for promoting agricultural high-quality development in southern Tibet through pairing assistance to Tibet from the perspective of agricultural power,and proposes some strategies,such as inheriting agricultural cultural heritage,promoting the upgrading of modern seed industry,enhancing the characteristic advantages of highland barley(naked barley)and animal husbandry industries,and developing edible fungi and cold water fish industries.
基金This work was supported by the National Natural Science Foundation of China(Nos.12275115 and 12175097)the Educational Department of Liaoning Province(No.LJKMZ20221410).
文摘In this article,a comprehensive study of the fission process of Th,U,Pu,and Cm isotopes using a Yukawa-folded meanfield plus standard pairing model is presented.The study focused on analyzing the effects of the pairing interaction on the fragment mass distribution and its dependence on nuclear elongation.The significant role of pairing interactions in the fragment mass distributions of^(230)Th,^(234)U,^(240)Pu,and^(246)Cm was demonstrated.Numerical analysis revealed that increasing the pairing interaction strength decreased the asymmetric fragment mass distribution and increased the symmetric distribution.Furthermore,the odd-even mass differences at symmetric and asymmetric fission points were examined,highlighting their sensitivity to changes in the pairing interaction strength.Systematic analysis of the Th,U,Pu,and Cm isotope fragment mass distributions demonstrated the effectiveness of the model in reproducing the experimental data.In addition,the effects of the zero-point energy and half-width parameter on the fragment mass distribution for^(240)Pu were explored.Thus,this study provides valuable insights into the fission process by emphasizing the importance of pairing interactions and their relationship with nuclear elongation.
基金funded by the Startup Foundation from Nantong University (03083074)partially supported by the National Natural Science Foundation of China (31771862)+1 种基金Special Funds for Technology Innovation of Fujian Agriculture and Forestry University(KFA20001A)the Research Program of Guangxi Key Laboratory for Sugarcane Biology (GXKLSCB-20190203)。
文摘Autopolyploidy and allopolyploidy may represent an evolutionary advantage and are more common in plants than assumed. However, less attention has been paid to autopolyploidy than to allopolyploidy,and its evolutionary consequences are largely unclear, especially for plants with high ploidy levels. In this study, we developed oligonucleotide(oligo)-based chromosome painting probes to identify individual chromosomes in S. spontaneum. Using fluorescence in situ hybridization(FISH), we investigated chromosome behavior during pachytene, metaphase, anaphase, and telophase of meiosis I(MI) in autotetraploid,autooctoploid, and autodecaploid S. spontaneum clones. All autopolyploid clones showed stable diploidized chromosome behavior;so that homologous chromosomes formed almost exclusively bivalents during MI. Two copies of homologous chromosome 8 with similar sizes in the autotetraploid clone showed preferential pairing with each other with respect to the other copies. However, sequence variation analysis showed no apparent differences among homologs of chromosome 8 and all other chromosomes. We suggest that either the stable diploidized pairing or the preferential pairing between homologous copies of chromosome 8 in the studied autopolyploid sugarcane are accounted for by unknown mechanisms other than DNA sequence similarity. Our results reveal evolutionary consequences of stable meiotic behavior in autopolyploid plants.
基金financially supported by the National Key Research and Development Program of China (2021YFD1200605)the National Natural Science Foundation of China (32171961)。
文摘Wide hybridization is a strategy for broadening the genetic basis of wheat. Because an efficient method for inducing wheat–alien chromosome translocations will allow producing useful germplasm, it is desirable to discover new genes that induce chromosomal variation. In this study, chromosome 5P from A.cristatum was shown to induce many types of chromosomal structural variation in a common wheat background, including nonhomoeologous chromosome translocations, as revealed by genomic in situ hybridization, fluorescence in situ hybridization, and DNA marker analysis. Aberrant meiosis was associated with chromosomal structural variation, and aberrant meiotic behavior was observed in wheat–A.cristatum 5P monosomic and disomic addition lines, suggesting that the effect of chromosome 5P was independent of the number of chromosome 5P copies. Chromosome 5P disturbed homologous chromosome pairing at pachytene stage in a common wheat background, resulting in a high frequency of univalent formation and reduced crossing over. Thirteen genes involved in DNA repair or chromatin remodeling, including RAD52-like and MSH6 genes, were differentially expressed(upregulated) in wheat–A. cristatum 5P addition lines according to transcriptome analysis, implicating chromosome 5P in the process of meiotic double-strand break repair. These findings provide a new, efficient tool for inducing wheat–alien chromosome translocations and producing new germplasm.
基金Project supported by the National Natural Science Foundation of China(Grant No.12175107)the Natural Science Foundation of Nanjing University of Posts and Telecommunications(Grant Nos.NY219087 and NY220038)。
文摘Isotope effect on superconductive transition temperature(T_c)is an essential indicator to examine whether the mechanism of superconductors is conventional.Unconventional isotope effect of BiS_(2)-based superconductors has been previously reported in ambient-pressure tetragonal phase.However,to comprehensively ascertain the nature of superconductivity,the investigation of BiS_(2)-based system in high-pressure structure is highly desirable.In this work,we carried out the first-principles calculations of phonon spectra and superconductivity in high-pressure monoclinic phase of LaO_(0.5)F_(0.5)BiS_(2)with ^(32)S and ^(34)S,and observed that the corresponding isotope coefficient is 0.13≤α≤0.20.This value is much greater than that of BiS_(2)-based superconductors in ambient-pressure phase,but slightly smaller than that of conventional MgB_2.Taking into account the calculated T_(c) lower than experimental results,we finally conclude that the moderate phonon-mediated pairing plays a significant role in forming superconductivity of BiS_(2)-based system in high-pressure phase,moreover,the cooperative multiple paring interactions should also be considered.
文摘The combined lines having both phKL and Ph2-deficiency were obtained in the genetic background of common wheat (Triticum aestivum L.) landrace. These lines had normal fertility. In the wheat combined lines X Aegilops variabilis Eig. (or rye), a significant increase in the chiasmata of homoeologous pairing was shown by the phKL+Ph2(-) plants with respect to their phKL+Ph2 sibs, which indicates that Ph2-deficiency and phKL showed an additive effect on promoting pairing. The effects were shown in the increment of rod bivalents, ring bivalents and trivalents and reduction of univalents, of which, reduction of univalents was mainly due to the increment of rod bivalents. The combined lines are probably more desirable materials for alien gene transferring than phKL or Ph2(-) lines alone. In comparison with that of ph1b X Ae. variabilis (or rye), phKL+Ph2(-) X Ae. variabilis (or rye) show higher (or similar) numbers of rod bivalents, while the total chromosome pairing level significantly reduced that ascribed to the decrement in ring bivalents and multivalents. These results probably indicate the different genetic mechanisms for Ph1 and Ph2 or phKL on controlling homoeologous pairing.
基金supported by the National Natural Science Foundation of China(81703947)the Fundamental Research Funds for the Central Universities(2019-JYB-XJSJJ-011).
文摘Objective:To reveal the molecular mechanism underlying the compatibility of Salvia miltiorrhiza Bge(S.miltiorrhiza,Dan Shen)and C.tinctorius L.(C.tinctorius,Hong Hua)as an herb pair through network pharmacology and subsequent experimental validation.Methods:Network pharmacology was applied to construct an active ingredient-efficacy target-disease protein network to reveal the unique regulation pattern of s.miltiorrhiza and C.tinctorius as herb pair.Molecular docking was used to verify the binding of the components of these herbs and their potential targets.An H9c2 glucose hypoxia model was used to evaluate the efficacy of the components and their synergistic effects,which were evaluated using the combination index.Western blot was performed to detect the protein expression of these targets.Results:Network pharmacology analysis revealed 5 pathways and 8 core targets of s.miltiorrhiza and C.tinctorius in myocardial protection.Five of the core targets were enriched in the hypoxia-inducible factor-1(HIF-1)signaling pathway.S.miltiorrhiza-C.tinctorius achieved vascular tone mainly by regulating the target genes of the HIF-1 pathway.As an upstream gene of the HIF-1 pathway,STAT3 can be activated by the active ingredients cryptotanshinone(Ctan),salvianolic acid B(Sal.B),and myricetin(Myric).Cell experiments revealed that Myric,Sal.B,and Ctan also exhibited synergistic myocardial protective activity.Molecular docking verified the strong binding of Myric,Sal.B,and Ctan to STAT3.Western blot further showed that the active ingredients synergistically upregulated the protein expressionof STAT3.Conclusion:The pharmacodynamic transmission analysis revealed that the active ingredients of S.miltiorrhiza and C.tinctorius can synergistically resist ischemia through various targets and pathways.This study provides a methodological reference for interpreting traditional Chinese medicine compatibility.
基金supported by the National Natural Science Foundation of China(Grant Nos.92165204,12174454,12488201,and 12325403)the National Key Research and Development Program of China(Grant Nos.2023YFA1406500,2022YFA1602601,2022YFA140280,and 22022YFA1403201)+2 种基金the Guangdong Basic and Applied Basic Research Funds(Grant Nos.2024B1515020040 and 2021B1515120015)Guangzhou Basic and Applied Basic Research Funds(Grant No.2024A04J6417)Guangdong Provincial Key Laboratory of Magnetoelectric Physics and Devices(Grant No.2022B1212010008)。
文摘This review provides a comprehensive overview of current research on the structural,electronic,and magnetic characteristics of the recently discovered high-temperature superconductor La_(3)Ni_(2)O_(7) under high pressures.We present the experimental results for synthesizing and characterizing this material,derived from measurements of transport,thermodynamics,and various spectroscopic techniques,and discuss their physical implications.We also explore theoretical models proposed to describe the electronic structures and superconducting pairing symmetry in La_(3)Ni_(2)O_(7),highlighting the intricate interplay between electronic correlations and magnetic interactions.Despite these advances,challenges remain in growing high-quality samples free of extrinsic phases and oxygen deficiencies and in developing reliable measurement tools for determining diamagnetism and other physical quantities under high pressures.Further investigations in these areas are essential to deepening our understanding of the physical properties of La_(3)Ni_(2)O_(7) and unlocking its superconducting pairing mechanism.
基金The Open Research Fund of National Mobile Communications Research Laboratory of Southeast University(No.2013D02)the Open Research Fund of National Key Laboratory of Electromagnetic Environment of China Research Institute of Radio Wave Propagation(No.201500013)the National Natural Science Foundation of China(No.61271230,61472190)
文摘To improve the reliable performance of information transmission in cooperative relay networks, the scheme of the max-rate spatial channel pairing (SCP) based on maximum ratio combining (MRC) is proposed. The scheme includes three steps: channel phase cancellation, MRC, and SCP. Eventually, the solution of the scheme is modeled as convex optimization. The objective function of the optimization problem is to maximize the transmission rate and the optimization variable is the strategy of pairing between the uplink spatial sub-channels of each user and the corresponding downlink spatial ones. The theorem of the arrangement inequalities is adopted to obtain the approximate closed-form solution of the optimal pairing for this convex optimization. Simulation results demonstrate that compared to the existing distributed space-time block coding and coherent combined schemes without SCP, the proposed max-rate SCP plus MRC algorithm achieves appreciable improvements in symbol error rate in medium and high signal-to-noise ratio regimes. The achievable performance gain is due to the use of maxrate SCP.
基金supported by the National Natural Science Foundation of China(22379100,U21A20312)the Shenzhen Science and Technology Program(Grant No.20231121200418001)+1 种基金the Guangdong Basic and Applied Basic Research Foundation(2022B1515120084)the Key Project of Department of Education of Guangdong Province(2023ZDZX3020)。
文摘Electrochemical co-reduction of nitrate(NO_(3)^(-))and carbon dioxide(CO_(2))has been widely regarded as a promising route to produce urea under ambient conditions,however the yield rate of urea has remained limited.Here,we report an atomically ordered intermetallic pallium-zinc(PdZn)electrocatalyst comprising a high density of PdZn pairs for boosting urea electrosynthesis.It is found that Pd and Zn are responsible for the adsorption and activation of NO_(3)^(-)and CO_(2),respectively,and thus the co-adsorption and co-activation NO_(3)^(-)and CO_(2) are achieved in ordered PdZn pairs.More importantly,the ordered and well-defined PdZn pairs provide a dual-site geometric structure conducive to the key C-N coupling with a low kinetical barrier,as demonstrated on both operando measurements and theoretical calculations.Consequently,the PdZn electrocatalyst displays excellent performance for the co-reduction to generate urea with a maximum urea Faradaic efficiency of 62.78%and a urea yield rate of 1274.42μg mg^(-1) h^(-1),and the latter is 1.5-fold larger than disordered pairs in PdZn alloys.This work paves new pathways to boost urea electrosynthesis via constructing ordered dual-metal pairs.
基金This study is supported by the National Key Research and Development Program of China(2017YFB0307500).
文摘Implementing a new energy-saving electrochemical synthesis system with high commercial value is a strategy of the sustainable development for upgrading the bulk chemicals preparation technology in the future.Here,we report a multiple redox-mediated linear paired electrolysis system,combining the hydrogen peroxide mediated cathode process with the I2 mediated anode process,and realize the conversion of furfural to furoic acid in both side of the dividedflow cell simultaneously.By reasonably controlling the cathode potential,the undesired water splitting reaction and furfural reduction side reactions are avoided.Under the galvanostatic electrolysis,the two-mediated electrode processes have good compatibility,which reduce the energy consumption by about 22%while improving the electronic efficiency by about 125%.This system provides a green electrochemical synthesis route with commercial prospects.
文摘The prevalence of smartphones is deeply embedded in modern society,impacting various aspects of our lives.Their versatility and functionalities have fundamentally changed how we communicate,work,seek entertainment,and access information.Among the many smartphones available,those operating on the Android platform dominate,being the most widely used type.This widespread adoption of the Android OS has significantly contributed to increased malware attacks targeting the Android ecosystem in recent years.Therefore,there is an urgent need to develop new methods for detecting Android malware.The literature contains numerous works related to Android malware detection.As far as our understanding extends,we are the first ones to identify dangerous combinations of permissions and system calls to uncover malicious behavior in Android applications.We introduce a novel methodology that pairs permissions and system calls to distinguish between benign and malicious samples.This approach combines the advantages of static and dynamic analysis,offering a more comprehensive understanding of an application’s behavior.We establish covalent bonds between permissions and system calls to assess their combined impact.We introduce a novel technique to determine these pairs’Covalent Bond Strength Score.Each pair is assigned two scores,one for malicious behavior and another for benign behavior.These scores serve as the basis for classifying applications as benign or malicious.By correlating permissions with system calls,the study enables a detailed examination of how an app utilizes its requested permissions,aiding in differentiating legitimate and potentially harmful actions.This comprehensive analysis provides a robust framework for Android malware detection,marking a significant contribution to the field.The results of our experiments demonstrate a remarkable overall accuracy of 97.5%,surpassing various state-of-the-art detection techniques proposed in the current literature.