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"Gu, Cheng"
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The hidden land : the garrison system and the Ming dynasty
\"'The Hidden Land' means that a large amount of land in the Ming dynasty (1368-1644) was 'hidden' or unknown, since the land was managed by both the administrative and the military systems, and only the former was made public while the latter was being hidden due to confidentiality issues. This is one of the author's creative findings as a result of his solid textual research and rigorous argumentation. Since the Ming state management system had a great impact on the land, the population, the taxes and corvâee, the imperial examinations, the justice, the grass-roots organizations and the frontier ethnics during the 500 years from Ming to Qing (1636-1912), the views on the garrisons and guards (weisuo) in the military system are of great help to review the essential issues of the period, which were often misunderstood or neglected before. In addition, the author introduces the present situation, existing problems and basic historical materials in the Ming study which will be beneficial to the Ming researchers and enthusiasts\"-- Provided by publisher.
Book
Construction and Classification of Symmetry-Protected Topological Phases in Interacting Fermion Systems
The classification and lattice model construction of symmetry-protected topological (SPT) phases in interacting fermion systems are very interesting but challenging. In this paper, we give a systematic fixed-point wave function construction of fermionic SPT (FSPT) states for generic fermionic symmetry groupGf=Z2f×ω2Gbwhich is a central extension of bosonic symmetry groupGb(may contain time-reversal symmetry) by the fermion parity symmetry groupZ2f={1,Pf}. Our construction is based on the concept of an equivalence class of finite-depth fermionic symmetric local unitary transformations and decorating symmetry domain wall picture, subjected to certain obstructions. We also discuss the systematical construction and classification of boundary anomalous SPT states which leads to a trivialization of the corresponding bulk FSPT states. Thus, we conjecture that the obstruction-free and trivialization-free constructions naturally lead to a classification of FSPT phases. Each fixed-point wave function admits an exactly solvable commuting-projector Hamiltonian. We believe that our classification scheme can be generalized to point and space group symmetry as well as continuum Lie group symmetry.
Journal Article
Separating water isotopologues using diffusion-regulatory porous materials
The discovery of a method to separate isotopologues, molecular entities that differ in only isotopic composition
1
, is fundamentally and technologically essential but remains challenging
2
,
3
. Water isotopologues, which are very important in biological processes, industry, medical care, etc. are among the most difficult isotopologue pairs to separate because of their very similar physicochemical properties and chemical exchange equilibrium. Herein, we report efficient separation of water isotopologues at room temperature by constructing two porous coordination polymers (PCPs, or metal–organic frameworks) in which flip-flop molecular motions within the frameworks provide diffusion-regulatory functionality. Guest traffic is regulated by the local motions of dynamic gates on contracted pore apertures, thereby amplifying the slight differences in the diffusion rates of water isotopologues. Significant temperature-responsive adsorption occurs on both PCPs: H
2
O vapour is preferentially adsorbed into the PCPs, with substantially increased uptake compared to that of D
2
O vapour, facilitating kinetics-based vapour separation of H
2
O/HDO/D
2
O ternary mixtures with high H
2
O separation factors of around 210 at room temperature.
The authors demonstrate efficient separation of water isotopologues at room temperature using two porous coordination polymers that amplify their diffusion-rate difference.
Journal Article
Towards a Complete Classification of Symmetry-Protected Topological Phases for Interacting Fermions in Three Dimensions and a General Group Supercohomology Theory
The classification and construction of symmetry-protected topological (SPT) phases in interacting boson and fermion systems have become a fascinating theoretical direction in recent years. It has been shown that (generalized) group cohomology theory or cobordism theory gives rise to a complete classification of SPT phases in interacting boson or spin systems. The construction and classification of SPT phases in interacting fermion systems are much more complicated, especially in three dimensions. In this work, we revisit this problem based on an equivalence class of fermionic symmetric local unitary transformations. We construct very general fixed-point SPT wave functions for interacting fermion systems. We naturally reproduce the partial classifications given by special group supercohomology theory, and we show that with an additionalB˜H2(Gb,Z2)structure [the so-called obstruction-free subgroup ofH2(Gb,Z2)], a complete classification of SPT phases for three-dimensional interacting fermion systems with a total symmetry groupGf=Gb×Z2fcan be obtained for unitary symmetry groupGb. We also discuss the procedure for deriving a general group supercohomology theory in arbitrary dimensions.
Journal Article
Emergence of Gapless Quantum Spin Liquid from Deconfined Quantum Critical Point
Quantum spin liquids (QSLs) as novel phases of matter with long-range entanglement and deconfined quantum critical points (DQCPs) as descriptions for unconventional phase transitions between two ordered states beyond the standard paradigm, such as the transition between antiferromagnetic (AFM) and valence-bond solid (VBS) phases, are two representative emerging phenomena. These implications for understanding correlated materials and developing theoretical frameworks for many-body physics are of crucial importance. Here, we show that a gapless QSL can naturally emerge from a DQCP. Via large-scale tensor network simulations of a square-lattice spin-1/2frustrated Heisenberg model, both QSL-state and DQCP-type AFM-VBS transitions are observed. By tuning the coupling constants, the AFM-VBS transition vanishes, and instead, a gapless QSL phase gradually develops in between. Remarkably, along the phase boundaries of AFM-QSL and QSL-VBS transitions, we always observe the same correlation-length exponents,ν≈1.0, which is intrinsically different from the one of the DQCP-type transition, indicating new types of universality classes. Our results explicitly demonstrate a new scenario for understanding the emergence of gapless QSL from an underlying DQCP. The discovered QSL phase survives in a large region of tuning parameters, and we expect its experimental realization in solid-state materials or quantum simulators.
Journal Article
Vortex-Line Condensation in Three Dimensions: A Physical Mechanism for Bosonic Topological Insulators
Bosonic topological insulators (BTIs) in three dimensions are symmetry-protected topological phases protected by time-reversal and boson number conservation symmetries. BTIs in three dimensions were first proposed and classified by the group cohomology theory, which suggests two distinct root states, each carrying a Z2 index. Soon after, surface anomalous topological orders were proposed to identify different root states of BTIs, which even leads to a new BTI root state beyond the group cohomology classification. In this paper, we propose a universal physical mechanism via vortex-line condensation from a 3D superfluid to achieve all three root states. It naturally produces a bulk topological quantum field theory description for each root state. Topologically ordered states on the surface are rigorously derived by placing topological quantum field theory on an open manifold, which allows us to explicitly demonstrate the bulk-boundary correspondence. Finally, we generalize the mechanism to ZN symmetries and discuss potential symmetry-protected topological phases beyond the group cohomology classification.
Journal Article
PGBTR: a powerful and general method for inferring bacterial transcriptional regulatory networks
Predicting bacterial transcriptional regulatory networks (TRNs) through computational methods is a core challenge in systems biology, and there is still a long way to go. Here we propose a powerful, general, and stable computational framework called PGBTR (Powerful and General Bacterial Transcriptional Regulatory networks inference method), which employs Convolutional Neural Networks (CNN) to predict bacterial transcriptional regulatory relationships from gene expression data and genomic information. PGBTR consists of two main components: the input generation step PDGD (Probability Distribution and Graph Distance) and the deep learning model CNNBTR (Convolutional Neural Networks for Bacterial Transcriptional Regulation inference). On the real
Escherichia coli
and
Bacillus subtilis
datasets, PGBTR outperforms other advanced supervised and unsupervised learning methods in terms of AUROC (Area Under the Receiver Operating Characteristic Curve), AUPR (Area Under Precision-Recall Curve), and F1-score. Moreover, PGBTR exhibits greater stability in identifying real transcriptional regulatory interactions compared to existing methods. PGBTR provides a new software tool for bacterial TRNs inference, and its core ideas can be further extended to other molecular network inference tasks and other biological problems using gene expression data.
Journal Article
Symmetry-Protected Topological Orders in Interacting Bosonic Systems
Symmetry-protected topological (SPT) phases are bulk-gapped quantum phases with symmetries, which have gapless or degenerate boundary states as long as the symmetries are not broken. The SPT phases in free fermion systems, such as topological insulators, can be classified; however, it is not known what SPT phases exist in general interacting systems. We present a systematic way to construct SPT phases in interacting bosonic systems. Just as group theory allows us to construct 230 crystal structures in three-dimensional space, we use group cohomology theory to systematically construct different interacting bosonic SPT phases in any dimension and with any symmetry, leading to the discovery of bosonic topological insulators and superconductors.
Journal Article
Duality of Interactions Between TGF-β and TNF-α During Tumor Formation
The tumor microenvironment is essential for the formation and development of tumors. Cytokines in the microenvironment may affect the growth, metastasis and prognosis of tumors, and play different roles in different stages of tumors, of which transforming growth factor β (TGF-β) and tumor necrosis factor α (TNF-α) are critical. The two have synergistic and antagonistic effect on tumor regulation. The inhibition of TGF-β can promote the formation rate of tumor, while TGF-β can promote the malignancy of tumor. TNF-α was initially determined to be a natural immune serum mediator that can induce tumor hemorrhagic necrosis, it has a wide range of biological activities and can be used clinically as a target to immune diseases as well as tumors. However, there are few reports on the interaction between the two in the tumor microenvironment. This paper combs the biological effect of the two in different aspects of different tumors. We summarized the changes and clinical medication rules of the two in different tissue cells, hoping to provide a new idea for the clinical application of the two cytokines.
Journal Article
Efficient photocatalytic production of hydrogen peroxide using dispersible and photoactive porous polymers
Developing efficient artificial photocatalysts for the biomimetic photocatalytic production of molecular materials, including medicines and clean energy carriers, remains a fundamentally and technologically essential challenge. Hydrogen peroxide is widely used in chemical synthesis, medical disinfection, and clean energy. However, the current industrial production, predominantly by anthraquinone oxidation, suffers from hefty energy penalties and toxic byproducts. Herein, we report the efficient photocatalytic production of hydrogen peroxide by protonation-induced dispersible porous polymers with good charge-carrier transport properties. Significant photocatalytic hydrogen peroxide generation occurs under ambient conditions at an unprecedented rate of 23.7 mmol g
–1
h
–1
and an apparent quantum efficiency of 11.3% at 450 nm. Combined simulations and spectroscopies indicate that sub-picosecond ultrafast electron “localization” from both free carriers and exciton states at the catalytic reaction centers underlie the remarkable photocatalytic performance of the dispersible porous polymers.
Current industrial production of hydrogen peroxide suffers from hefty energy penalties and toxic byproducts. Here, the authors report efficient photocatalytic production of hydrogen peroxide by protonation-induced dispersible porous polymers with good charge-carrier transport properties.
Journal Article