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Unconventional fermions in the immensely studied topological semimetals are the source for rich exotic topological properties. Here, using symmetry analysis and first-principles calculations, we propose the coexistence of multiple topological nodal structure in LaSb 2 , including topological nodal surfaces, nodal lines and in particular eightfold degenerate nodal points, which have been scarcely observed in a single material. Further, utilizing angle-resolved photoemission spectroscopy, we confirm the existence of nodal surfaces and eightfold degenerate nodal points in LaSb 2 . The intriguing multiple topological nodal structure might play a crucial role in giving rise to the large linear magnetoresistance. Our work renews the insights into the exotic topological phenomena in LaSb 2 .

Topological metals possess various types of symmetry-protected degenerate band crossings. When a topological metal becomes superconducting, the low-energy electronic excitations stemming from the band crossings located close to the Fermi level may contribute to highly unusual pairing symmetry and superconducting states. In this work, we study the electronic band structure of the time-reversal symmetry breaking superconductor LaNiGa 2 by means of quantum oscillation measurements. A comprehensive investigation combining angle-resolved high-field de Haas-van Alphen (dHvA) spectroscopy and first-principles calculations reveals the fermiology of LaNiGa 2 and verifies its nonsymmorphic Cmcm lattice symmetry, which promises nodal band crossings pinned at the Fermi level with fourfold degeneracies. Moreover, such nodal structures, proposed to play a crucial role giving rise to the interorbital triplet pairing, are indeed captured by our dHvA analysis. Our results identify LaNiGa 2 as a prototypical topological crystalline superconductor and highlight the putative contribution of low-energy nodal quasiparticles to unconventional superconducting pairing.

Background We have previously reported anatomical, histological, and gene expression characteristics of the nodal structure of rat skin surface and suggested its potential as an acupuncture point. However, the specific characteristics of the interactions among the genes expressed in this structure remain unclear. Objective We aimed to determine gene expression changes by analyzing interaction networks of genes up-regulated in nodal structures and to explore relationships with acupuncture points. Methods We investigated the relationship between the nodal structures and acupuncture points by analyzing the interactions of up-regulated genes, their Gene Ontology biological functions, and the characteristics of Kyoto Encyclopedia of Genes and Genomes pathways. RNA-seq and STRING analysis provided comprehensive information on these gene groups. Results Interactions between up-regulated genes in nodal structures were classified into three groups. The first group, which includes Wnt7b, Wnt3, and Wnt16, showed significant interactions in pathways such as Wnt signaling, Alzheimer’s disease, and regulation of stem cell pluripotency. The second group, composed of Fos, Dusp1, Pla2g4e, Pla2g4f, and Fgfr3, demonstrated a notable association with the MAPK signaling pathway. Lastly, the third group, consisting of Adcy1, Pla2g4e, Pla2g4f, and Dusp1 exhibited effective interactions with the inflammatory mediator regulation of TRP channels and serotonergic synapse. Conclusion Continued research on nodal structures where these genes are expressed is needed to improve our understanding of skin anatomy and physiology as well as their potential clinical utility as acupuncture points.

The article generalizes the global experience of research on communication geography with the goal to identify future directions of study of the spatial and temporal deployment and functioning of telecommunications networks. An original algorithm of semantic search for publications in bibliographic databases has returned about 400 articles on communication geography published in 1981–2020 in scientific journals worldwide. An analysis of these publications shows that six types of communications: fiber-optic, mobile, telephone, postal, telegraph, and satellite—have been studied within infrastructural, statistical, impact, streaming, and optimization directions of communication geography. Trends are identified using the methods of the moving average and bi-proportional indices. Linear extrapolation of trends in the number of publications by type of communications and by research directions suggests that in the future preference will be given to geographical study of fiber-optic and mobile networks within infrastructural and statistical approaches with the objective to optimize the line-nodal structure. Based on a comparative analysis of unsolved problems, it is established that the priority in future research should be given to the following meta-tasks: transferring the experience of geographical study of a given type of communications to other types; using big data of telecom operators for geographical analysis of the functioning of networks; transitioning from descriptive to constructive communication geography; identifying geographical patterns for deployment of telecommunication networks, and developing the concept of a territory telecommunications complex. The following research objects are identified as promising: machine-to-machine information exchange networks, 6G mobile communication networks, and multifunctional networks.

This study proposes a novel external steel-frame system equipped with viscoelastic nodal dampers for improving the seismic performance of reinforced concrete (RC) structures. The nodal dampers utilize viscoelastic materials to dissipate seismic energy through hysteretic shear deformation, thereby reducing the dynamic response of the main structure. An external steel frame is connected to the original RC frame through these dampers, forming an integrated load-bearing and energy-dissipating system. A series of shaking table tests were conducted on two models: the original RC frame and the retrofitted structure incorporating the external steel frame with viscoelastic nodal dampers. The tests investigated the acceleration and displacement responses under different seismic excitations, with peak ground accelerations ranging from 0.2 g to 1.0 g. The results demonstrate that the proposed system significantly enhances stiffness and energy dissipation capacity, effectively reducing floor acceleration and inter-story drift. Under moderate earthquakes, the external steel frame increases the overall stiffness, while under strong ground motion, the viscoelastic nodal dampers dominate energy dissipation. The maximum reduction in acceleration response reached 64%, and inter-story displacement was reduced by up to 52.4%. These findings confirm the system’s ability to provide both seismic strengthening and damping, offering a practical and sustainable solution for the seismic retrofit of existing RC structures.

We consider stationary waves on nonlinear quantum star graphs, i.e., solutions to the stationary (cubic) nonlinear Schrödinger equation on a metric star graph with Kirchhoff matching conditions at the centre. We prove the existence of solutions that vanish at the centre of the star and classify them according to the nodal structure on each edge (i.e., the number of nodal domains or nodal points that the solution has on each edge). We discuss the relevance of these solutions in more applied settings as starting points for numerical calculations of spectral curves and put our results into the wider context of nodal counting, such as the classic Sturm oscillation theorem.

Lightweight structures constitute an eminently important solution to the conservation of limited resources of energy in aeronautics and vehicle engineering. The increasing necessity to implement lightweight construction concepts for framework structures due to their vast application makes requirement-adapted node structures attractive for fiber-reinforced plastic composites (FRPC) components. Although the use of FRPC for framework structures is well-established by now, the node structures are still mostly made from aluminum or titanium, which results in additional costs and limits the achievable mass reduction. Hence solutions for FRPC node structures have to be developed. The aim of this work is the development and implementation of a productive, automated manufacturing technology based on the weaving process for complex node structures based on carbon fiber for automotive and aeronautics applications. The development of the woven concept for the realization of node structures is based on the fragmentation of the individual sub-elements. The sub-elements are virtually unwound into the layer and positioned one above the other. The warp threads are floated in the areas where the individual levels do not touch. The node structures are produced on the conventional weaving loom by flattening and weaving them as multi-surface woven fabrics in one piece. The tube profiles are produced seamlessly, and the connection points between the tubes are jointless. By pulling the warp yarns in one branch through the structure, the gap is closed and the 3D geometry is formed. The defined pulling of the warp yarns is the main component of this publication. This new technology allows for the weaving of complex, integrated node structures with multi-directional spatial branching without subsequent assembly requirements. These newly developed node structures show great potential for lightweight construction applications. They can be manufactured with good reproducibility and a high degree of automation. The results of this work indicate an enormous potential of the weaving technique for the cost effective manufacture of integrally designed, woven 3D semi-finished products for FRPC. Typical applications for node structures include stringers and floor frames in airplanes, machine components, car frame parts, such as A-, B-, or C-pillars.

Three experiments used postclass formation within‐class preference test performances to evaluate the effects of nodal distance on the relatedness of stimuli in equivalence classes. In Experiment 1, two 2‐node four‐member equivalence classes were established using the simultaneous protocol in which all of the baseline relations were trained together, after which all emergent relations probes were presented together. All training and testing was done using match‐to‐sample trials that contained two comparisons. After class formation, the effects of nodal distance were evaluated using within‐class preference tests that contained samples and both comparisons from the same class. These tests yielded inconsistent performances for most participants. Experiment 2 replicated Experiment 1, but a third null comparison was used on all trials during class formation. Thereafter, virtually all of the within‐class probes, for all participants, evoked performances that were consistent with the predicted effects of nodal distance, that is, the selection of comparisons that were nodally closer to the samples. It appears, then, that the establishment of the equivalence classes with a third null comparison induced control by nodal structure of the classes. Experiment 3 demonstrated the generality of these findings with larger classes that contained more nodal separations, that is, three‐node five‐member classes. Emergent‐relations tests conducted immediately after the within‐class tests showed the classes to be intact. Thus, the differential relatedness of stimuli in a class or their interchangeability depended on the content of a test trial: within‐class probes occasioned responding indicative of differential strength among the stimuli in the class, while cross‐class tests occasioned responding indicative of interchangeability of stimuli in the same class.

We study theoretically the effect of Zeeman field on the Bogoliubov–de Gennes quasiparticle excitation spectrum of a three-dimensional noncentrosymmetric ( s + p ) -wave model. The quasiparticle excitation spectrum may possess line nodes due to the mixing of s -wave and p -wave pairing in the absence of Zeeman field. Our calculations show that, depending on the magnitude and the orientation of an applied Zeeman field, a variety of nodal structures including nodal points, nodal lines, and nodal surfaces may be generated in the excitation spectrum. These results are corroborated by numerical computations of the low-temperature electronic specific heat. Specifically, we demonstrate rigorously that the zero-field nodal lines will be robust against a weak z -axis oriented Zeeman field. It is also found that the electronic specific heat calculated for a Zeeman field in the x – y plane may qualitatively account for the novel feature of specific heat observed experimentally in CePt 3 Si.

By definition, all of the stimuli in an equivalence class have to be functionally interchangeable with each other. The present experiment, however, demonstrated that this was not the case when using post‐class‐formation dual‐option response transfer tests. With college students, two 4‐node 6‐member equivalence classes with nodal structures of A→B→C→D→E→F were produced by training AB, BC, CD, DE' and EF. Then, unique responses were trained to the c and D stimuli in each class. The responses trained to c generalized to B and A, while the responses trained to D generalized to E and F. Thus, each 4‐node 6‐member equivalence class was bifurcated into two 3‐member functional classes: A→B→C and D→E→F, with class membership precisely predicted by nodal structure. A final emergent relations test documented the intactness of the underlying 4‐node 6‐member equivalence classes. The coexistence of the interchangeability of stimuli in an equivalence class and the bifurcation of such a class in terms of nodal structure was explained in the following manner. The conditional discriminations that are used to establish a class also imposes a nodal structure on the stimuli in the class. Thus, the stimuli in the class acquire two sets of relational properties. if the format of a test trial allows only one response option per class, responding on those trials will be in accordance with class membership and will not express the effects of nodal distance. if the format of a test trial allows more than one response option per class, responding on those trials will be determined by the nodal structure of the class. Thus, the relational properties expressed by the stimuli in an equivalence class are determined by the discriminative function served by the format of a test trial.