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Higher-order topological states, as emergent topological phases of matter, originating from condensed matter physics, have sparked a vibrant exploration of topological insulators. Their topologically protected multidimensional localized states are typically associated with nontrivial bulk band topology, and the significant impact of lattice geometry is unconsciously overlooked. Here, we construct coupled acoustic cavities on a two-dimensional honeycomb lattice to investigate the sensitivity of higher-order topological modes to the variations of edge contour. Fractional charge is utilized to accurately predict topological modes with distinct topological orders, in spite of the minimal bulk bandgaps inherent in the honeycomb lattice and bound states in the continuum. It is found that the presence and absence of the first-order and higher-order topological modes in the same topological phase are tightly linked to the sample boundaries, which can be demonstrated by both theoretical analysis and numerical calculation. Our study also discusses potential physical realization of geometry-dependent topological states across different platforms, providing inspiration for the prospective application of topological devices in acoustics. [ABSTRACT FROM AUTHOR]

Dissipation, often associated with plasmons, leads to decoherence and is generally considered fatal for quantum nonlinearities and entanglement. Counterintuitively, by introducing a dissipative plasmonic nanoantenna into a typical cavity quantum electrodynamics (QED) system, we unveil the wide existence of the atom-photon quasi-bound state (qBS), a kind of exotic eigenstate with anomalously small decay, in the hybrid plasmonic-photonic cavity. To derive the analytical condition of atom-photon qBS, we formulate a quantized two-mode model of the local density of states by connecting the interacting uncoupled cavity modes to the macroscopic QED. With resonant plasmon-photon coupling, we showcase the single-atom qBS that improves the efficiency of single-photon generation over one order of magnitude; and the two-atom qBS that significantly enhances spontaneous entanglement generation compared with a bare photonic cavity. Notably, such single-atom and multi-atom qBS can be simultaneously accessed in realistic plasmonic-photonic cavities, providing a versatile platform for advanced quantum technologies, such as quantum light sources, quantum computation, and quantum information.

The supervisory control of Petri nets aims to enforce the undesired behavior as unreachable by designing a set of control places. This work presents a set cover approach to design maximally permissive supervisors. For each first-met bad marking, an integer linear programming problem is developed to obtain a control place to prohibit it. An objective function is formulated to make the maximal number of first-met bad markings forbidden. Then, we develop a set covering approach to minimize the number of selected control places. The proposed approach can guarantee the maximal permissiveness of the obtained supervisor and provide a trade-off between structural complexity and computational cost. Several examples are considered to validate the proposed method. [ABSTRACT FROM AUTHOR]

Conducting contact state analysis enhances the stability of object grasping by an anthropomorphic robotic hand. The incorporation of soft materials grants the anthropomorphic robotic hand a compliant nature during interactions with objects, which, in turn, poses challenges for accurate contact state analysis. According to the characteristic of the anthropomorphic robotic hand's compliant contact, a kinetostatic modeling method based on the pseudo-rigid-body model is proposed. It can realize the mapping between contact force and driving torque. On this basis, the stable contact states of the anthropomorphic robotic hand under the envelope grasping mode are further analyzed, which are used to reasonably plan the contact position of the anthropomorphic robotic hand before grasping an object. Experimental results validate the efficacy of the proposed approach during grasping and ensure stable contact in the initial grasping stage. It significantly contributes to enhancing the reliability of the anthropomorphic robotic hand's ability to securely grasp objects. [ABSTRACT FROM AUTHOR]

The genus Acacia is a crucial source of industrial papermaking and timber, possessing significant economic value. Due to their nitrogen-fixing ability, rapid growth, and high tolerance to stress, Acacia species have become integral to short-term industrial timber forests, particularly in southern China and various other regions worldwide. Nevertheless, comparative genomic analyses of Acacia species remain limited, impeding the development of molecular markers for identifying and distinguishing between distinct Acacia species as well as distinguishing their wood counterparts from other tree species. To address this gap, we generated plastomic sequences from eight species commonly cultivated in Chinese plantation forests and compared them with existing data. Our findings revealed a generally conserved structure and gene content within the plastid genomes of Acacia. Notably, the dN/dS ratio of genes from distinct functional groups varied, particularly between ribosomal proteins and photosynthesis genes. Furthermore, phylogenetic analyses and sequence comparisons suggest that the introduction of Acacia to China may have been less diverse than previously thought or that interspecies introgression has occurred more frequently than previously documented. This study offers a valuable starting point for future research in this area and for improving timber quality through marker-assisted breeding. [ABSTRACT FROM AUTHOR]

Curcuma alismatifolia (Zingiberaceae) is an ornamental species with high economic value due to its recent rise in popularity among floriculturists. Cultivars within this species have mixed genetic backgrounds from multiple hybridization events and can be difficult to distinguish via morphological and histological methods alone. Given the need to improve identification resources, we carried out the first systematic study using plastomic data wherein genomic evolution and phylogenetic relationships from 56 accessions of C. alismatifolia were analyzed. The newly assembled plastomes were highly conserved and ranged from 162,139 bp to 164,111 bp, including 79 genes that code for proteins, 30 tRNA genes, and 4 rRNA genes. The A/T motif was the most common of SSRs in the assembled genomes. The Ka/Ks values of most genes were less than 1, and only two genes had Ka/Ks values above 1, which were rps15 (1.15), and ndhl (1.13) with petA equal to 1. The sequence divergence between different varieties of C. alismatifolia was large, and the percentage of variation in coding regions was lower than that in the non-coding regions. Such data will improve cultivar identification, marker assisted breeding, and preservation of germplasm resources. [ABSTRACT FROM AUTHOR]

Synergistically enhancing and realizing the value of grassland ecosystem services (ES) for economic activity is an important but challenging task for achieving sustainability in the karst desertification control (KDC). However, how to use grassland ES value characteristics in the KDC to make decisions on ES improvement, human well-being enhancement, and sustainable development remains unclear. In this paper, we took the contiguous region of karst desertification in Yunnan-Guangxi-Guizhou, China, a global hotspot, as the study area. Based on the valuation of the gross ecosystem product (GEP) and county economic intensity, we analyzed the structural and spatial characteristics of grassland GEP in the KDC using spatial analysis methods. We found that: (1) the grassland GEP in the KDC is mainly distributed in counties with low economic intensity (86.05% of the total number of counties) and vulnerable to losses caused by the livelihood of farmers; (2) the grassland GEP in the KDC is spatially small and scattered (the geographic concentration lies between 0.015 and 0.237), which makes it difficult to form industrial scale advantages; (3) the public product index (66.22–96.77%) and industry scale concentration (97.87–99.86%) of grassland GEP in the KDC are high, and most of the GEP is difficult to transform on the private market. Based on our findings, we proposed three corresponding recommendations for economic decision-making. The results of this study can provide a reference for economic decision-making regarding the management of grassland ES in karst areas with similar conditions and beyond. [ABSTRACT FROM AUTHOR]

We study two-dimensional (2D) isotropic quantum droplets (QDs) in dipolar binary Bose–Einstein condensates (BECs). The QDs are supported by the competition between the 2D form of the Lee-Huang-Yang (LHY) term and the isotropic dipole-dipole interactions (DDIs). Moreover, the DDIs in the 2D plane can be tuned to be either repulsive or attractive. Before that, QDs in dipolar BECs were often explored in three-dimensional (3D) systems, with competition between the attractive DDIs and the repulsive LHY term. Unlike the 3D system, the LHY term of the 2D binary system behaves in a logarithmic form, which can feature both attraction and repulsion. In this case, the QDs can be produced regardless of the interactions (attraction, repulsion, or zero) that the mean-field effect represents. In this paper, we model the aforementioned QDs via the 2D binary dipolar BECs with the competition between isotropic DDIs and the logarithmic LHY term. Their characteristic parameters (the peak density, I P , chemical potential, μ , and effective area, A eff ) using both numerical and theoretical methods are discussed. The centripetal collision and oblique collision between moving QDs are also studied. [ABSTRACT FROM AUTHOR]

In response to the issue of virus contamination in the cold-chain warehouse or hospital environment under the influence of the COVID-19, we propose the design work of a disinfection robot based on the UVC radiation mechanism using the low-computational path optimization at-the-edge. To build a surface disinfection robot with less computing power to generate a collision-free path with shorter total distance in studies, a 2D map is used as a graph-based approach to automatically generate a closed-loop disinfection path to cover all the accessible surfaces. The discrete disinfection points from the map are extracted with effective disinfection distances and sorted by a nearest-neighbor (NN) search over historical trajectory data and improved A * algorithm to obtain an efficient coverage path to all accessible boundaries of the entire area. The purpose of improved A * algorithm with NN is not to find the optimal path solution but to optimize one with reasonable computing power. The proposed algorithm enhances the path-finding efficiency by a dynamically weighted heuristic function and reduces the path turning angles, which improves the path smoothness significantly requiring less computing power. The Gazebo simulation is conducted, and the prototype disinfection robot has been built and tested in a real lab environment. Compared with the classic A * algorithm, the improved A * algorithm with NN has improved the path-finding efficiency and reduced the path length while covering the same area. Both the simulation and experimental results show that this approach can provide the design to balance the tradeoffs among the path-finding efficiency, smoothness, disinfection coverage, and computation resources. [ABSTRACT FROM AUTHOR]

This paper addresses the fault diagnosis problem of PLC-based systems that can be modeled as Petri nets under a certain level of abstraction. The existing Petri-net-based fault diagnosis approaches often associate transitions and/or places with sensors and require that any change in sensor readings needs to be treated by a PLC, leading to a situation that the PLC would be too busy processing the changes in sensor readings to perform other tasks. This paper assumes that a PLC does not monitor the changes of readings of sensors all the time, but periodically reads the values of sensors when needed. The system output is defined as a marking sequence interleaved with possible observed transitions. A fault diagnosis algorithm is developed by defining and solving integer linear programing (ILP) problems whose size is regardless of the length of the system output. The proposed approach enjoys high computational efficiency compared with other ILP-based approaches and is more suitable for fault diagnosis of PLC-based systems with low computing power. [ABSTRACT FROM AUTHOR]

Accurate prediction of open reading frames (ORFs) is important for studying and using genome sequences. Ribosomes move along mRNA strands with a step of three nucleotides and datasets carrying this information can be used to predict ORFs. The ribosome-protected footprints (RPFs) feature a significant 3-nt periodicity on mRNAs and are powerful in predicting translating ORFs, including small ORFs (sORFs), but the application of RPFs is limited because they are too short to be accurately mapped in complex genomes. In this study, we found a significant 3-nt periodicity in the datasets of populational genomic variants in coding sequences, in which the nucleotide diversity increases every three nucleotides. We suggest that this feature can be used to predict ORFs and develop the Python package 'OrfPP', which recovers ~83% of the annotated ORFs in the tested genomes on average, independent of the population sizes and the complexity of the genomes. The novel ORFs, including sORFs, identified from single-nucleotide polymorphisms are supported by protein mass spectrometry evidence comparable to that of the annotated ORFs. The application of OrfPP to tetraploid cotton and hexaploid wheat genomes successfully identified 76.17% and 87.43% of the annotated ORFs in the genomes, respectively, as well as 4704 sORFs, including 1182 upstream and 2110 downstream ORFs in cotton and 5025 sORFs, including 232 upstream and 234 downstream ORFs in wheat. Overall, we propose an alternative and supplementary approach for ORF prediction that can extend the studies of sORFs to more complex genomes. [ABSTRACT FROM AUTHOR]

We consider the adiabatic geometric phase (AGP) in the sum frequency generation process under the undepleted pump approximation. The Bloch sphere is stretched or compressed by adjusting the modulation wave vector, $\Delta$ , which is one of the control parameters of quasiphase matching (QPM). In this paper, two kinds of parametric rotation schemes on the sphere are studied: elliptical rotation and elliptical wedge rotation. We find that the AGP generated in the elliptical rotation is related to the length of the $\Delta$ axis of the ellipse, but there is a certain point where the AGP is independent, while the AGP in the elliptical wedge rotation shows great stability and does not depend on the shape of the ellipsoid. The results further demonstrate the superior flexibility of the wedge scheme, which helps to suppress the uncertainty in the generation of AGPs. [ABSTRACT FROM AUTHOR]

The geometric phase of light has been demonstrated in various platforms of the linear optical regime, raising interest both for fundamental science as well as applications, such as flat optical elements. Recently, the concept of geometric phases has been extended to nonlinear optics, following advances in engineering both bulk nonlinear photonic crystals and nonlinear metasurfaces. These new technologies offer a great promise of applications for nonlinear manipulation of light. In this review, we cover the recent theoretical and experimental advances in the field of geometric phases accompanying nonlinear frequency conversion. We first consider the case of bulk nonlinear photonic crystals, in which the interaction between propagating waves is quasi-phase-matched, with an engineerable geometric phase accumulated by the light. Nonlinear photonic crystals can offer efficient and robust frequency conversion in both the linearized and fully-nonlinear regimes of interaction, and allow for several applications including adiabatic mode conversion, electromagnetic nonreciprocity and novel topological effects for light. We then cover the rapidly-growing field of nonlinear Pancharatnam-Berry metasurfaces, which allow the simultaneous nonlinear generation and shaping of light by using ultrathin optical elements with subwavelength phase and amplitude resolution. We discuss the macroscopic selection rules that depend on the rotational symmetry of the constituent meta-atoms, the order of the harmonic generations, and the change in circular polarization. Continuous geometric phase gradients allow the steering of light beams and shaping of their spatial modes. More complex designs perform nonlinear imaging and multiplex nonlinear holograms, where the functionality is varied according to the generated harmonic order and polarization. Recent advancements in the fabrication of three dimensional nonlinear photonic crystals, as well as the pursuit of quantum light sources based on nonlinear metasurfaces, offer exciting new possibilities for novel nonlinear optical applications based on geometric phases. [ABSTRACT FROM AUTHOR]

Background: Tibial Pilon fractures are severe fractures accompanied by soft tissue injury. Although open reduction and internal fixation (ORIF) are effective in treating Pilon fractures, there is a controversy over time to surgery due to reported postoperative complications. However, there is no systematic review evaluating the difference of postoperative complications between early and delayed ORIF for treating pilon fractures. Methods: Relevant literature written in English will be searched through PubMed, Cochrane Library, Embase, MEDLINE, and Web of Science. The study aims to compare the effects and complications of early and delayed ORIF for treating fresh pilon fractures in adult patients. The primary outcome will be infection rate, fracture union time, nonunion and malunion rate. And the secondary outcome will be metalwork removal, amputation, and ankle function grade. Two reviewers will independently assess the eligibility of the studies according to the pre-defined inclusion and exclusion criteria. A meta-analysis for the available data will be conducted using Revman 5.3. To measure effect size, odds ratios (ORs) and mean difference will be used for dichotomous and continuous data, respectively. Statistical heterogeneity will be explored. And a random-effects model or a fixed-effects will be used in pooled data on the basis of the existence or absence of heterogeneity. Subgroup analysis will be conducted to identify sources of heterogeneity and sensitivity analysis to test the results' robustness. We will assess the risk of bias by four different quality assessment tools according to the study design. Publication bias will be evaluated by funnel plot. The study data will be stored in the Open Science Framework website. PROSPERO registration number: CRD42020207465 [ABSTRACT FROM AUTHOR]

Quantum compiling aims to construct a quantum circuit V by quantum gates drawn from a native gate alphabet, which is functionally equivalent to the target unitary U. It is a crucial stage for the running of quantum algorithms on noisy intermediate-scale quantum (NISQ) devices. However, the space for structure exploration of quantum circuit is enormous, resulting in the requirement of human expertise, hundreds of experimentations or modifications from existing quantum circuits. In this paper, we propose a variational quantum compiling (VQC) algorithm based on reinforcement learning, in order to automatically design the structure of quantum circuit for VQC with no human intervention. An agent is trained to sequentially select quantum gates from the native gate alphabet and the qubits they act on by double Q-learning with ϵ-greedy exploration strategy and experience replay. At first, the agent randomly explores a number of quantum circuits with different structures, and then iteratively discovers structures with higher performance on the learning task. Simulation results show that the proposed method can make exact compilations with less quantum gates compared to previous VQC algorithms. It can reduce the errors of quantum algorithms due to decoherence process and gate noise in NISQ devices, and enable quantum algorithms especially for complex algorithms to be executed within coherence time. [ABSTRACT FROM AUTHOR]

We consider possibilities to grasp and drag one-dimensional solitons in two-component Bose–Einstein condensates (BECs), under the action of gravity, by tweezers induced by spatially confined spin–orbit (SO) coupling applied to the BEC, with the help of focused laser illumination. Solitons of two types are considered, semi-dipoles and mixed modes. We find critical values of the gravity force, up to which the solitons may be held or transferred by the tweezers. The dependence of the critical force on the magnitude and spatial extension of the localized SO interaction, as well as on the soliton's norm and speed (in the transfer regime), are systematically studied by means of numerical methods, and analytically with the help of a quasi-particle approximation for the soliton. In particular, a noteworthy finding is that the critical gravity force increases with the increase of the transfer speed (i.e., moving solitons are more robust than quiescent ones). Nonstationary regimes are addressed too, by considering abrupt application of gravity to solitons created in the weightless setting. In that case, solitons feature damped shuttle motion, provided that the gravity force does not exceed a dynamical critical value, which is smaller than its static counterpart. The results may help to design gravimeters based on ultracold atoms. [ABSTRACT FROM AUTHOR]

Solitons are self-trapped modes existing in various nonlinear systems. Creating stable solitons in two- and three-dimensional settings is a challenging goal in various branches of physics. Several methods have been developed theoretically and experimentally to achieve this, but few of them can support stable multi-dimensional solitons in free space. Recently, a new scheme using spin-orbit-coupling (SOC) has been proposed to create stable 2D solitons in Bose–Einstein condensates (BECs). This paper reviews recent theoretical progress on creating stable 2D solitons in spinor dipolar BEC with SOC, combined with long-range dipole-dipole interaction (DDI), Zeeman splitting (ZS) and contact nonlinearity, in free space. The continuous family of stable symmetric vortex solitons (SVS), asymmetric vortex solitons (AVS), as well as gap solitons (GS) is found via different settings. Their existence and stability conditions are summarized and discussed in detail. The mobility properties of these types of solitons are also addressed. For SVS, a potential method to manipulate its shape and mobility is investigated. These results are supposed to enrich our understanding of 2D solitons and help create multi-dimensional solitons in experiments. [ABSTRACT FROM AUTHOR]

We demonstrate an optical diode by building a domain wall with one-dimensional waveguide array. The domain wall can be described by dividing the one-dimensional waveguide array into two equal parts, which have different refractive index, so that the waveguide array exists local potential. A Gaussian beam is kicked moving toward the domain wall and interacts with it. Transmission and reflection during the interaction between the Gaussian beam and the domain wall are found by changing related parameters. The detailed behavior of the Gaussian beam dynamics is analyzed numerically. Transmission of the Gaussian beam in one direction is much bigger than the opposite under certain circumstances and optical nonreciprocity is found in such a model, high transmission ratio of such model up to 300 is obtained. Thus the system can serve as an optical diode. [ABSTRACT FROM AUTHOR]

We study the fundamental modes trapped in a rotating ring with the local strength of the linear and nonlinear potentials modulated as V (θ − ωz) and − V (θ − ωz), respectively, where θ is the azimuthal angle and the modulation pattern is V (θ) ∼cos2θ, which is a double-well profile in the domain of − π ≤ θ < π. The model, based on the nonlinear Schrödinger equation with periodic boundary conditions, applies to light propagation in a twisted waveguiding pipe, and to a Bose–Einstein condensate loaded into a toroidal trap under the action of a rotating π-out-of-phase linear potential and nonlinear pseudopotential, induced by means of a rotating optical field and the Feshbach resonance, respectively. In the case of self-focusing, three types of fundamental trapped modes are identified, one symmetric and two asymmetric. This is different from the recently considered setting with purely linear or nonlinear rotating potential. In that setting, only two fundamental modes can be found. The shapes and stability of these modes, together with the transitions between them, are investigated in the first rotational Brillouin zone. The symmetry breaking, which transforms the symmetric mode into the asymmetric ones, is strongly affected by the modulation depth and the rotation speed of V (θ, ω). The ground-state mode is identified among these three types, and the evolution of an unstable asymmetric mode, which is chiefly trapped in one potential well, features Josephson oscillations between the two wells. [ABSTRACT FROM AUTHOR]

We theoretically investigate the optical Anderson localization in the disordered photorefractive lattices under different strength of saturable self-defocusing nonlinearity. Via continuously increasing the value of the nonlinear parameter and applying numerical simulations respectively, a critical behavior, a transformation from a localized state to a spreading state, is found. We use different initial power of the probe and obtain a series of critical values of the nonlinear parameter. Below the critical value, the localizing effect is enhanced with the increase of the nonlinear parameter. While above the critical value, the localized state is destroyed. We give a study of the critical behavior and the critical values corresponding to different physical parameters, including the intensity of the self-defocusing nonlinearity, the intensity of the lattice-forming beams and the randomness strength of the structure. [ABSTRACT FROM AUTHOR]

Holographic fabrication of large-size photonic crystals with a lens array is proposed and demonstrated. A substantial increase of the usable size for two-dimensional and three-dimensional photonic crystals is obtained compared with the template prepared with a mask and a single-lens system. [ABSTRACT FROM AUTHOR]

Transmission enhancement via transverse mode control through an aluminum hollow tapered waveguide with a sub-100 nm aperture is simulated with optical wavefront modulations via a binary optical element. Efficient delivery of an input field by exciting the fundamental propagating mode near the apex is realized, giving rise to a significant transmission enhancement through the nano-tip. [ABSTRACT FROM AUTHOR]