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Recently, it has been realized that in some systems internal space rotation can induce energy amplification for scattered waves, similar to rotation in real space. In particularly, it has been shown that energy extraction is possible for a Q-ball, a stationary non-topological soliton that is coherently rotating in its field space. In this paper, we generalize the analysis to the case of boson stars, and show that the same energy extraction mechanism still works for boson stars. [ABSTRACT FROM AUTHOR]

Environmental flow is increasingly used in restoring degraded riparian vegetation. To assess the impact of environmental flow on plant community characteristics and to provide a scientific basis for the subsequent restoration and management of the riparian vegetation at Yongding River (Beijing Section), field surveys were conducted before and after environmental flow application in 2022. Before environmental flow application, sixty-nine species were identified, and the number of species increased to ninety-six species after environmental flow application. Community similarity analysis found that riparian vegetation communities were dominated by emergent hygrophytic plants and the introduced Xanthium italicum had the largest contribution before environmental flow application. The environmental flow increased the proportion of submerged plants, four submerged plant species were among the top ten species contributing to dissimilarity. Canonical correspondence analysis found that soil total nitrogen and organic matter significantly influenced riparian plant richness. Non-metric multidimensional scaling analysis showed that after environmental flow application, the similarity of plant communities in the mountain and plain sections increased. However, it is worth noting that the invasive species Bidens frondosa became dominant in the mountain section, whereas the invasive species Xanthium italicum was widely distributed in the plain section after environmental flow application. The results showed that environmental flow increased mountain section’s vegetation uniformity and plant species richness in the plain section, enhancing plant communities similarity in both regions. Environmental water application supports the spread of both native and invasive species; thus, future management should prioritize the timing of environmental flow to prevent invasive species’ widespread dissemination. [ABSTRACT FROM AUTHOR]

The transition-edge sensor (TES) as a type of low-temperature superconducting detector offers superior sensitivity due to its low thermal noise. In this work, we present a prototype TES bolometer designed for cosmic microwave background (CMB) polarization measurements. This TES is made of aluminum doped with a low concentration of manganese (2000 ppm by atomic percentage), and is deposited on the SiNx membrane which connects to the silicon substrate via narrow legs. In order to calculate its electrothermal parameters we have performed dark characterizations, which include measuring voltage-current (IV) curve at different bath temperatures, square-wave time response at various bias voltages, and noise level. This TES bolometer shows a noise equivalent power (NEP) of about 5 × 10 - 17 W/ Hz , which meets the requirement of CMB observation. However, its saturation power is smaller and time constant is larger than what are expected. We have analyzed the reasons and will make corresponding improvements in our future work. [ABSTRACT FROM AUTHOR]

Existing mobile robots mostly use graph search algorithms for path planning, which suffer from relatively low planning efficiency owing to high redundancy and large computational complexity. Due to the limitations of the neighborhood search strategy, the robots could hardly obtain the most optimal global path. A global path planning algorithm, denoted as EDG*, is proposed by expanding nodes using a well-designed expanding disconnected graph operator (EDG) in this paper. Firstly, all obstacles are marked and their corners are located through the map pre-processing. Then, the EDG operator is designed to find points in non-obstruction areas to complete the rapid expansion of disconnected nodes. Finally, the EDG* heuristic iterative algorithm is proposed. It selects the candidate node through a specific valuation function and realizes the node expansion while avoiding collision with a minimum offset. Path planning experiments were conducted in a typical indoor environment and on the public dataset CSM. The result shows that the proposed EDG* reduced the planning time by more than 90% and total length of paths reduced by more than 4.6%. Compared to A*, Dijkstra and JPS, EDG* does not show an exponential explosion effect in map size. The EDG* showed better performance in terms of path smoothness, and collision avoidance. This shows that the EDG* algorithm proposed in this paper can improve the efficiency of path planning and enhance path quality. [ABSTRACT FROM AUTHOR]

The development of a low-cost and multifunctional sensing and monitoring device would be a meaningful endeavor. In this research, a novel spirooxazine with a two double-bonded structure, designated as (1-butyl-3,3-dimethylspiro[indoline-2,3'-naphtho[2,1-b] [1, 4]oxazine]-5,8'-diyl)bis(methylene)bis(2-methylacrylate) (SO-DB), was successfully synthesized and incorporated as a functional cross-linker into a polyhydroxyethyl methacrylate hydrogel system. Notably, this hydrogel system based on a single responsive component exhibits photo-pH dual responsiveness, which avoids the addition of multiple components that may affect other properties of the hydrogel. Particularly, in comparison to traditional surface grafting and physical blending, crosslinking with SO-DB leads to the formation of a denser and stronger three-dimensional polymer network in the stimuli-responsive hydrogel. Under UV light irradiation, spirooxazine absorbs energy and undergoes cleavage of the Cspiro-O bond, transforming the molecule from a colorless closed-ring state to an open-ringed photomerocyanine (PMC) state. Under acidic conditions, hydrophobic spirooxazine undergoes a reversible protonation open-ring reaction, forming a stable intermediate form, a protonated photomerocyanine (PMCH). Furthermore, the addition of SO-DB as a crosslinking agent to the hydrogel system increases its stability and fatigue resistance, and maintains good repeatability over 24 light cycles and 7 pH cycles without performance loss. Such approach to generate stimulus-responsive hydrogels could have great potential in both wearable biosensors and food packaging field. [ABSTRACT FROM AUTHOR]