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Continents are formed by the amalgamation of numerous micro-terranes and island arcs, so they have spatially varying lithosphere strengths. The crème brûlée (CB) model and the jelly sandwich (JS) model have been commonly used to describe continental lithosphere strength–depth variations. Depending on the strength of the continental lower crust, the CB and JS models can be further subdivided into two subclasses in which the I subclass (CB-I and JS-I) and II subclass (CB-II and JS-II), respectively, have a strong or weak lower crust. During the continental collision, lithosphere deformation is the byproduct of the comprehensive interaction of multiple terranes. Here we used 2-D thermomechanical numerical models that contain three continental terranes to systematically explore the effects of terranes with various strengths on continental deformation and studied the effects of different rheological assumptions on terrane deformation. We found four types of lithosphere deformation patterns: collision, subduction, thickening and delamination, and replacement. These simulation patterns are seen in observed deformation patterns and structures in East Asia, suggesting they are likely to be naturally occurring modes of intracontinental orogenesis.

The mechanism of the charge density wave transition in quasi one-dimensional blue bronzes is still debated. Here, the authors report evidence of a Luttinger liquid in the normal state of blue bronzes and Holstein polarons below the transition temperature, revealing the important role of electron-phonon coupling in the transition.

Topological superconductors are potentially important for future quantum computation, but they are very rare in nature. Here, the authors observe topological surface states acquiring a nodeless superconducting gap with similar magnitude as that of the bulk states in 2M-WS2, suggesting an intrinsic topological superconductor.

The high-latitude atmosphere is a dynamic region with processes that respond to forcing from the Sun, magnetosphere, neutral atmosphere, and ionosphere. Historically, the dominance of magnetosphere–ionosphere interactions has motivated upper atmospheric studies to use magnetic coordinates when examining magnetosphere–ionosphere–thermosphere coupling processes. However, there are significant differences between the dominant interactions within the polar cap, auroral oval, and equatorward of the auroral oval. Organising data relative to these boundaries has been shown to improve climatological and statistical studies, but the process of doing so is complicated by the shifting nature of the auroral oval and the difficulty in measuring its poleward and equatorward boundaries. This study presents a new set of open–closed magnetic field line boundaries (OCBs) obtained from Active Magnetosphere and Planetary Electrodynamics Response Experiment (AMPERE) magnetic perturbation data. AMPERE observations of field-aligned currents (FACs) are used to determine the location of the boundary between the Region 1 (R1) and Region 2 (R2) FAC systems. This current boundary is thought to typically lie a few degrees equatorward of the OCB, making it a good candidate for obtaining OCB locations. The AMPERE R1–R2 boundaries are compared to the Defense Meteorological Satellite Program Special Sensor J (DMSP SSJ) electron energy flux boundaries to test this hypothesis and determine the best estimate of the systematic offset between the R1–R2 boundary and the OCB as a function of magnetic local time. These calibrated boundaries, as well as OCBs obtained from the Imager for Magnetopause-to-Aurora Global Exploration (IMAGE) observations, are validated using simultaneous observations of the convection reversal boundary measured by DMSP. The validation shows that the OCBs from IMAGE and AMPERE may be used together in statistical studies, providing the basis of a long-term data set that can be used to separate observations originating inside and outside of the polar cap.

The chemical inventory of protoplanetary midplanes is the basis for forming planetesimals. Among them, solid-state reactions based on CO/CO _2 toward molecular complexity on interstellar dust grains have been studied in theoretical and laboratory work. The physicochemical interactions between ice, constituted mainly of H _2 O, and dust surfaces are limited to a few experimental studies focusing on vacuum ultraviolet and cosmic-ray processing. In this work, the erosion of C dust grains induced by X-ray irradiation of H _2 O ice was systematically investigated for the first time. The work aims to provide a better understanding of the reaction mechanism using selectively isotope-labeled oxygen/carbon species in kinetic analysis. Ultrahigh vacuum experiments were performed to study the interstellar ice analog on submicron, thick C dust at ∼13 K. H _2 O or O _2 ice was deposited on the presynthesized amorphous C dust and exposed to soft X-ray photons (250–1250 eV). Fourier-transform infrared spectroscopy was used to monitor in situ the newly formed species as a function of the incident photon fluence. Field emission scanning electron microscopy was used to monitor the morphological changes of (non-)eroded carbon samples. The X-ray processing of the ice/dust interface leads to the formation of CO _2 , which further dissociates and forms CO. Carbonyl groups are formed by oxygen addition to grain surfaces and are confirmed as intermediate species in the formation process. The yields of CO and CO _2 were found to be dependent on the thickness of the carbon layer. The astronomical relevance of the experimental findings is discussed.

For research the behavior and after effects which had been resulted from the coated reactive fragments impacting the steel targets, the 14.5mm ballistic rifle had been adopted to complete the experiments that the 6mm Q235A steel targets was impacted by the steel fragments and the reactive fragments, composed by metal/ polymer coated with steel, with the same mass and size. Afterwards, the v50 ballistic-limited velocity and the law of the damage effects on the after effect-targets had been discovered. The results indicate that the integral strength of the coated reactive fragments was lower than that of the inert steel fragments, which lead to the reductions of the penetration performance. The v50 ballistic-limited velocity, resulted of the coated reactive fragments impacting the 6mm Q235A steel targets, was 709m/s and it was 1.33 times than that of the steel fragments with the same mass and size. The reaming enhanced effects on the after effect-targets could be produced in the condition that the impact velocity of coated reactive fragments should be greater than 900m/s while the residual velocity should be greater than 181m/s, and that it had been strengthened along with the impact velocity increased. The probable reasons of the damage enhanced effects had been analyzed that the coupled damage effects had been resulted from two parts energy. The results will provide important references to the engineering application of reactive fragments for warheads.

We develop a formalism for photoionization (PI) and potential energy curves (PECs) of Rydberg atoms in ponderomotive optical lattices and apply it to examples covering several regimes of the optical-lattice depth. The effect of lattice-induced PI on Rydberg-atom lifetime ranges from noticeable to highly dominant when compared with natural decay. The PI behavior is governed by the generally rapid decrease of the PI cross sections as a function of angular-momentum ( ℓ ), lattice-induced ℓ -mixing across the optical-lattice PECs, and interference of PI transition amplitudes from the lattice-mixed into free-electron states. In GHz-deep lattices, ℓ -mixing leads to a rich PEC structure, and the significant low- ℓ PI cross sections are distributed over many lattice-mixed Rydberg states. In lattices less than several tens-of-MHz deep, atoms on low- ℓ PECs are essentially ℓ -mixing-free and maintain large PI rates, while atoms on high- ℓ PECs trend towards being PI-free. Characterization of PI in GHz-deep Rydberg-atom lattices may be beneficial for optical control and quantum-state manipulation of Rydberg atoms, while data on PI in shallower lattices are potentially useful in high-precision spectroscopy and quantum-computing applications of lattice-confined Rydberg atoms.

The intrinsic magnetic topological insulator MnBi_{2}Te_{4} exhibits rich topological effects such as quantum anomalous Hall effect and axion electrodynamics. Here, by combining the use of synchrotron and laser light sources, we carry out comprehensive and high-resolution angle-resolved photoemission spectroscopy studies on MnBi_{2}Te_{4} and clearly identify its topological electronic structure. In contrast to theoretical predictions and previous studies, we observe topological surface states with diminished gap forming a characteristic Dirac cone. We argue that the topological surface states are mediated by multidomains of different magnetization orientations. In addition, the temperature evolution of the energy bands clearly reveals their interplay with the magnetic phase transition by showing interesting differences between the bulk and surface states, respectively. The investigation of the detailed electronic structure of MnBi_{2}Te_{4} and its temperature evolution provides important insight into not only the exotic properties of MnBi_{2}Te_{4}, but also the generic understanding of the interplay between magnetism and topological electronic structure in magnetic topological quantum materials.

Grit – passion and perseverance for long-term goals – has been empirically shown to be a positive predictor of success across multiple contexts. The current study developed a new framework of grit within a framework of self-regulatory behaviours. Here, a qualitative approach was assumed to obtain interview data from chief innovation officers and chief information officers within technologically intensive industries. Empirical evidence was used to inductively determine the underlying cognitive-affective processing that influences gritty behaviour. Overall, six strategies were identified: temporal perspective, perpetual evaluation, motivational orientation, strength and resource gathering, system thinking and framing. Organisations may utilise the grit model developed here to enhance the grittiness of their innovation leaders by building effective cognitive-affective strategies.

To find out whether the Interleukin-6 (IL-6)/signal transducer and activator of transcription 3 (STAT3) signaling pathway is involved in the expression of hepcidin in the mouse brain in vivo, we investigated the phosphorylation of STAT3, as well as the expression of hepcidin mRNA, ferroportin 1 (Fpn1) and ferritin light chain (Ft-L) proteins in the cortex and hippocampus of LPS-treated wild type (IL-6+/+) and IL-6 knockout (IL-6-/-) mice. We demonstrated that IL-6 knockout could significantly reduce the response of hepcidin mRNA, phospho-STAT3, Fpn1 and Ft-L protein expression to LPS treatment, in both the cortex and hippocampus of mice. Also, Stattic, an inhibitor of STAT3, significantly reduced the expression of phospho-STAT3 and hepcidin mRNA in the cortex and hippocampus of the LPS-treated wild type mice. These findings provide in vivo evidence for the involvement of the IL-6/STAT3 signaling pathway in the expression of hepcidin.

The effects of naturally acidified seawater on shell traits were quantified through the comparison of dove snails (Family: Columbellidae) Anachis misera from vent environments with Euplica sp. from non-vent sites in northeastern Taiwan. Samples of A. misera were collected around a shallow vent (24.8341° N, 121.96191° E), which included the east, south, southwest, and northwest sites. An absence of Anachis snails was found in the most acidic north site (pH 7.19–7.25). Based on the similarities of protein expression profiles, the Anachis snails were classified into two groups, i.e., V-South (pH 7.78–7.82) and V-Rest (pH 7.31–7.83). Comparing their shell traits to the non-vent Euplica sp. from Da-xi (DX) and Geng-fang (GF) (pH 8.1–8.2), a difference in shell shape (shell width : shell length) was found, with the populations having more globular shells than the non-vent ones. The means of shell width were significantly different among sites (p < 0.01), with a descending order of GF > DX > V-South and V-Rest. The relationships of shell length to total weight were curvilinear for both Anachis and Euplica snails. The logarithmically transformed slopes differed significantly among sites, and the mean body weight of the GF population was greater than that of the others (p < 0.01). Positive correlations between shell length and shell thickness of body whorl (T1) and penultimate whorl (T2) were only observed in non-vent GF and DX populations. Anachis snails from vent sites were thinner in T1 and T2 compared to the Euplica snails from non-vent sites (p < 0.05). Within each vent group, shell thickness between T1 and T2 was insignificantly different. Between vent groups, T1 and T2 from V-Rest showed a decrease of 10.6 and 10.2%, respectively, compared to V-South ones. The decrease of T1 and T2 between vent Anachis snails and non-vent Euplica snails was as great as 55.6 and 29.0%, respectively. This was the first study to compare snail's morphological traits under varying shallow-vent stresses with populations previously classified by biochemical responses. Overall, the shallow-vent-based findings provide additional information from subtropics on the effects of acidified seawater on gastropod snails in natural environments.

The beneficial effect of magnesium supplementation on exercise performance has been reported by many researchers. In the present study, the effect of nigari, a concentrate of deep seawater containing high magnesium levels, on exercise performance, was examined. Gerbils were given double-distilled water or nigari (18 mg · kg-1, po) orally 30 min before exercise. All animals were subjected to forced exercise on a treadmill for 90 min at three successive speeds of 10, 15, and 20 m · min-1. The retention numbers were recorded. The retention numbers were 85.0 ± 21.0, 46.0 ± 9.7, and 48.0 ± 14.2 in the control group, and 44.0 ± 10.9, 23.0 ± 8.4, and 13.0 ± 4.8 in the nigari-treated group at the three speeds, respectively. The retention numbers were significantly reduced at higher speeds (by 50% at 15 and 73% at 20 m · min-1, respectively) in the nigari-treated group when compared to those of the control group, respectively. Thus, nigari administration appeared to reduce retention numbers and enhance exercise performance in gerbils.