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In this work, we first derive the corrections to the instanton configuration of the flavored gauge field in the D4-D8 model with generic flavor numbers. Then, as the instanton configuration on the D8-branes represents equivalently baryon in this model, keeping our corrections in hand, we systemically study the spectrum of baryon, heavy-light baryon or heavy-light meson and find it is possible to fit the experimental data with the meson data in this model. Besides, we briefly outline how to include the interaction of glueball and heavy-light meson or baryon with our corrections, evaluate numerically the decay rate of the heavy-light meson or baryonic matter involving glueball. Since it is possible to fit all the spectra with same choice of the parameters to the experimental data, we believe our corrections improve the framework of D4-D8 model and the corrected instanton configuration is also useful to investigate other properties of baryon in holography., Comment: 34 pages, 2 figures

The bone age, reflecting the degree of development of the bones, can be used to predict the adult height and detect endocrine diseases of children. Both examinations of radiologists and variability of operators have a significant impact on bone age assessment. To decrease human intervention , machine learning algorithms are used to assess the bone age automatically. However, conventional supervised deep-learning methods need pre-labeled data. In this paper, based on the convolutional auto-encoder with constraints (CCAE), an unsupervised deep-learning model proposed in the classification of the fingerprint, we propose this model for the classification of the bone age and baptize it BA-CCAE. In the proposed BA-CCAE model, the key regions of the raw X-ray images of the bone age are encoded, yielding the latent vectors. The K-means clustering algorithm is used to obtain the final classifications by grouping the latent vectors of the bone images. A set of experiments on the Radiological Society of North America pediatric bone age dataset (RSNA) show that the accuracy of classifications at 48-month intervals is 76.15%. Although the accuracy now is lower than most of the existing supervised models, the proposed BA-CCAE model can establish the classification of bone age without any pre-labeled data, and to the best of our knowledge, the proposed BA-CCAE is one of the few trails using the unsupervised deep-learning method for the bone age assessment.

We derive residue formulas for the regularized integrals (introduced by Li-Zhou) on configuration spaces of elliptic curves. Based on these formulas, we prove that the regularized integrals satisfy holomorphic anomaly equations, providing a mathematical formulation of the so-called contact term singularities. We also discuss residue formulas for the ordered $A$-cycle integrals and establish their relations with those for the regularized integrals., Comment: Appendices added. To appear in Communications in Mathematical Physics

According to the gauge-gravity duality, we systematically study the Schwinger effect and electric instability with anisotropy in a top-down holographic approach. The anisotropic black brane and bubble (soliton) background in IIB supergravity are employed and the dual theories in these backgrounds are expected to be anisotropic theory at finite temperature and anisotropic theory with confinement respectively. Then performing the potential analysis, we find due to the anisotropy, the potential barrier behaves oppositely with parallel and perpendicular electric fields, and this behavior agrees with the previous study about the quark potential with anisotropy in this system. Afterwards, we evaluate the pair production rate by solving the equation of motion for a fundamental string numerically which reveals the consistent behavior with the potential analysis. Furthermore, the probe D7-brane as flavor is introduced into the bulk in order to investigate the electric instability. The vacuum decay rate can be obtained by evaluating the imaginary part of the D7-brane action which again agrees with our potential analysis. Solving the associated constraint of gauge field strength on the flavor brane, we finally obtain the V-A curve displaying the distinct behavior of the conductivity in parallel and perpendicular direction which is in agreement with some bottom-up and phenomenologically holographic approaches in anisotropic fluid. Accordingly, we believe this work may be remarkable to study the electric features in strongly coupled anisotropic system., Comment: Fix some typoes ,adjust some figures, upgrade 2 references and add some comments

Information reconciliation (IR), which corrects the errors in the sifted keys, directly determines the secure key rate and the link distance of quantum key distribution (QKD) systems. In this article, we propose an appending information reconciliation (AIR) scheme based on polar codes, which achieves high efficiency and ultra-low failure probability simultaneously, by gradually disclosing the bit values of the polarized channels with high error probability. The experimental results show that the efficiency of the proposed AIR scheme is closer to the Shannon limit, compared with the state-of-the-art implemented polar codes-based IR schemes, with the overall failure probability around 1E-8, especially when performed with smaller block sizes. Moreover, the efficiency of the proposed AIR scheme is 1.046, when the block size is 1 Gb and the quantum bit error rate of 0.02. Therefore, the proposed AIR scheme can further eradicate the performance gap between theory and implementation for QKD systems., Comment: 12 pages, 6 pages, 4 tables

The cosmic microwave background (CMB), carrying the inhomogeneous information of the very early universe, is of great significance for understanding the origin and evolution of our universe. However, observational CMB maps contain serious foreground contaminations from several sources, such as galactic synchrotron and thermal dust emissions. Here, we build a deep convolutional neural network (CNN) to recover the tiny CMB signal from various huge foreground contaminations. Focusing on the CMB temperature fluctuations, we find that the CNN model can successfully recover the CMB temperature maps with high accuracy, and that the deviation of the recovered power spectrum $C_\ell$ is smaller than the cosmic variance at $\ell>10$. We then apply this method to the current Planck observation, and find that the recovered CMB is quite consistent with that disclosed by the Planck collaboration, which indicates that the CNN method can provide a promising approach to the component separation of CMB observations. Furthermore, we test the CNN method with simulated CMB polarization maps based on the CMB-S4 experiment. The result shows that both the EE and BB power spectra can be recovered with high accuracy. Therefore, this method will be helpful for the detection of primordial gravitational waves in current and future CMB experiments. The CNN is designed to analyze two-dimensional images, thus this method is not only able to process full-sky maps, but also partial-sky maps. Therefore, it can also be used for other similar experiments, such as radio surveys like the Square Kilometer Array., Comment: 20 pages, 25 figures, and 3 tables, updated citations in section 1. The code repository is available at https://github.com/Guo-Jian-Wang/cmbNNCS

Based on the gauge-gravity duality, we study the three-dimensional QCD ($\mathrm{QCD}_{3}$) and Chern-Simons theory by constructing the anisotropic black D3-brane solution in IIB supergravity. The deformed bulk geometry is obtained by performing a double Wick rotation and dimension reduction which becomes an anisotropic bubble configuration exhibiting confinement in the dual theory. And its anisotropy also reduces to a Chern-Simons term due to the presence of the dissolved D7-branes or the axion field in bulk. Using the bubble geometry, we investigate the the ground-state energy density, quark potential, entanglement entropy and the baryon vertex according to the standard methods in the AdS/CFT dictionary. Our calculation shows that the ground-state energy illustrates degenerate to the Chern-Simons coupling coefficient which is in agreement with the properties of the gauge Chern-Simons theory. The behavior of the quark tension, entanglement entropy and the embedding of the baryon vertex further implies strong anisotropy may destroy the confinement. Afterwards, we additionally introduce various D7-branes as flavor and Chern-Simons branes to include the fundamental matter and effective Chern-Simons level in the dual theory. By counting their orientation, we finally obtain the associated topological phase in the dual theory and the critical mass for the phase transition. Interestingly the formula of the critical mass reveals the flavor symmetry, which may relate to the chiral symmetry, would be restored if the anisotropy increases greatly. As all of the analysis is consistent with characteristics of quark-gluon plasma, we therefore believe our framework provides a remarkable way to understand the features of Chern-Simons theory, the strong coupled nuclear matter and its deconfinement condition with anisotropy., Comment: 41pages, 11 figures, 3 tables, fix several typos and add more comments in this version

In long-wavelength moir\'e superlattices of stacked transition metal dichalcogenides (TMDs), structural reconstruction ubiquitously occurs, which has reported to impact significantly their electronic properties. However, complete microscopic understandings of the interplay between the lattice reconstruction and alteration of electronic properties, and their further response to external perturbations in the reconstructed TMDs moir\'e superlattice are still lacking. Here, using scanning tunneling microscopy (STM) and scanning tunneling spectroscopy (STS) combined with first-principles calculation, we study the strain-dependent structural reconstruction and its correlated electronic reconstruction in long-wavelength H-type WS$_{2}$ moir\'e superlattice at nanometer scale. We observe that the long-wavelength WS$_{2}$ moir\'e superlattices experiencing strong atomic reconstruction transform into a hexagonal array of screw dislocations separating large-sized H-stacked domains. Both the geometry and the moir\'e wavelength of the moir\'e superlattice are dramatically tuned by external intralayer heterostrain in our experiment. Remarkably, the STS measurements further demonstrate that the location of the K point in conduction band is modulated sensitively by strain-induced lattice deformation at nanometer scale in this system, with the maximum energy shift reaching up to 300 meV. Our results highlight that intralayer strain plays a vital role in determining structural and electronic properties in TMD moir\'e superlattice.

Extensive investigations on topological phase transition (TPT) in three-dimensional compounds have been done. whereas, rare in two-dimensional systems, let alone noncentrosymmetric materials. In this work, based on first-principles calculations, we explore an inversion symmetry broken structural ReC2H monolayer. We reveal that it undergoes two TPTs, namely from normal insulator to Z2 topological insulator and back to normal insulator, at the critical biaxial strain of 2.3% and 7.8%, respectively. The band inversion occurs at the generic momentum in the first TPT, while at high symmetric K point in the second one. Usually, band inversion is identified by the exchange in the components or irreducible representations of the wavefunctions. These quantities can be easily obtained in theoretical calculation but hard to be detected in experimental techniques like Angle-resolved photoemission spectroscopy. It is well known that nonlinear optical (NLO) response is very sensitive to the components and symmetries of the engaged bands, which also incorporates information of band topology. Therefore, we study the shift current, one of the widely explored NLO responses in noncentrosymmetric systems, during the two TPTs. We find that in both cases band inversion leads to the sign change of shift vectors around the momenta where the bandgap closes and reopens. Whereas the shift current, as the overall contribution of shift vectors weighted by the absorption rate in the whole Brillouin zone, may keep its direction. This work offers insight that a scrutinized examination is highly demanded in utilizing shift current to detect TPT.