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Layered transition metal dichalcogenides have a rich phase diagram and they feature two-dimensionality in numerous physical properties. Co1/3NbS2 is one of the newest members of this family where Co atoms are intercalated into the van der Waals gaps between NbS2 layers. We study the three-dimensional electronic band structure of Co1/3NbS2 using both surface and bulk sensitive angle-resolved photoemission spectroscopy. We show that the electronic bands do not fit into the rigid band shift picture after the Co intercalation. Instead, Co1/3NbS2 displays a different orbital character near the Fermi level compared to the pristine NbS2 compound and has a clear band dispersion in the kz direction despite its layered structure. Our photoemission study demonstrates the out-of-plane electronic correlations introduced by the Co intercalation, thus offering a different perspective on this compound. Finally, we propose how Fermi level tuning could lead to exotic phases such as spin density wave instability.

Quantum states induced by single-atomic impurities are at the frontier of physics and material science. While such states have been reported in high-temperature superconductors and dilute magnetic semiconductors, they are unexplored in topological magnets which can feature spin-orbit tunability. Here we use spin-polarized scanning tunneling microscopy/spectroscopy (STM/S) to study the engineered quantum impurity in a topological magnet Co3Sn2S2. We find that each substituted In impurity introduces a striking localized bound state. Our systematic magnetization-polarized probe reveals that this bound state is spin-down polarized, in lock with a negative orbital magnetization. Moreover, the magnetic bound states of neighboring impurities interact to form quantized orbitals, exhibiting an intriguing spin-orbit splitting, analogous to the splitting of the topological fermion line. Our work collectively demonstrates the strong spin-orbit effect of the single-atomic impurity at the quantum level, suggesting that a nonmagnetic impurity can introduce spin-orbit coupled magnetic resonance in topological magnets.

Kagome-nets, appearing in electronic, photonic and cold-atom systems, host frustrated fermionic and bosonic excitations. However, it is rare to find a system to study their fermion-boson many-body interplay. Here we use state-of-the-art scanning tunneling microscopy/spectroscopy to discover unusual electronic coupling to flat-band phonons in a layered kagome paramagnet, CoSn. We image the kagome structure with unprecedented atomic resolution and observe the striking bosonic mode interacting with dispersive kagome electrons near the Fermi surface. At this mode energy, the fermionic quasi-particle dispersion exhibits a pronounced renormalization, signaling a giant coupling to bosons. Through the self-energy analysis, first-principles calculation, and a lattice vibration model, we present evidence that this mode arises from the geometrically frustrated phonon flat-band, which is the lattice bosonic analog of the kagome electron flat-band. Our findings provide the first example of kagome bosonic mode (flat-band phonon) in electronic excitations and its strong interaction with fermionic degrees of freedom in kagome-net materials.

A quantum system may be purified, i.e., projected into a pure state, faster if one applies feedback operations during the measurement process. However, the existing results suggest that such an enhancement is only possible when the measurement efficiency exceeds 0.5, which is difficult to achieve experimentally. We address the task of finding the global optimal feedback control for purifying a single qubit in the presence of measurement inefficiency. We use the Bloch vector length, a more physical and practical quantity than purity, to assess the quality of the state, and employ a backward-iteration algorithm to find the globally optimal strategy. Our results show that a speedup is available for quantum efficiencies well below 0.5, which opens the possibility of experimental implementation in existing systems.

Insufficient understanding about the immune evasion mechanism leads to the inability in predicting current immunotherapy effects in clear cell renal cell carcinoma (ccRCC) and sensitizing ccRCC to immunotherapy. RNA binding proteins (RBPs) can promote tumor progression and immune evasion. However, research on RBPs, particularly m6A reader YTHDF3, in ccRCC development and immune evasion is limited. In this study, we found that YTHDF3 level was downregulated in ccRCC and was an independent prognostic biomarker for ccRCC. Decreased YTHDF3 expression was correlated with the malignancy, immune evasion, and poor response to anti‐programmed death ligand 1 (PD‐L1)/CTLA‐4 in ccRCC. YTHDF3 overexpression restrained ccRCC cell malignancy, PD‐L1 expression, CD8+ T cell infiltration and activities in vivo, indicating its inhibitory role in ccRCC development and immune evasion. Mechanistically, YTHDF3 WT was found to have phase separation characteristics and suppress ccRCC malignancy and immune evasion. Whereas YTHDF3 mutant, which disrupted phase separation, abolished its function. YTHDF3 enhanced the degradation of its target mRNA HSPA13 by phase separation and recruiting DDX6, resulting in the downregulation of the downstream immune checkpoint PD‐L1. HSPA13 overexpression restored ccRCC malignancy and immune evasion suppressed by YTHDF3 overexpression. In all, our results identify a new model of YTHDF3 in regulating ccRCC progression and immune evasion through phase separation. [ABSTRACT FROM AUTHOR]

Charge density wave (CDW) orders in vanadium-based kagome metals have recently received tremendous attention, yet their origin remains a topic of debate. The discovery of ScV6Sn6, a bilayer kagome metal featuring an intriguing 3 × 3 × 3 CDW order, offers a novel platform to explore the underlying mechanism behind the unconventional CDW. Here, we combine high-resolution angle-resolved photoemission spectroscopy, Raman scattering and density functional theory to investigate the electronic structure and phonon modes of ScV6Sn6. We identify topologically nontrivial surface states and multiple van Hove singularities (VHSs) in the vicinity of the Fermi level, with one VHS aligning with the in-plane component of the CDW vector near the K ¯ point. Additionally, Raman measurements indicate a strong electron-phonon coupling, as evidenced by a two-phonon mode and new emergent modes. Our findings highlight the fundamental role of lattice degrees of freedom in promoting the CDW in ScV6Sn6.The mechanism of charge density wave order in V-based kagome metals has been debated. Here the authors use a range of experimental techniques combined with ab initio calculations to study the electronic structure and phonon modes of ScV6Sn6, revealing the dominant role of strong electron-phonon coupling. [ABSTRACT FROM AUTHOR]

Charge density wave (CDW) orders in vanadium-based kagome metals have recently received tremendous attention, yet their origin remains a topic of debate. The discovery of ScV6Sn6, a bilayer kagome metal featuring an intriguing 3 × 3 × 3 CDW order, offers a novel platform to explore the underlying mechanism behind the unconventional CDW. Here, we combine high-resolution angle-resolved photoemission spectroscopy, Raman scattering and density functional theory to investigate the electronic structure and phonon modes of ScV6Sn6. We identify topologically nontrivial surface states and multiple van Hove singularities (VHSs) in the vicinity of the Fermi level, with one VHS aligning with the in-plane component of the CDW vector near the K ¯ point. Additionally, Raman measurements indicate a strong electron-phonon coupling, as evidenced by a two-phonon mode and new emergent modes. Our findings highlight the fundamental role of lattice degrees of freedom in promoting the CDW in ScV6Sn6. The mechanism of charge density wave order in V-based kagome metals has been debated. Here the authors use a range of experimental techniques combined with ab initio calculations to study the electronic structure and phonon modes of ScV6Sn6, revealing the dominant role of strong electron-phonon coupling. [ABSTRACT FROM AUTHOR]

The effect of thermo-mechanical coupling was considered in order to obtain the fatigue life of spilt torque transmission row angular contact ball bearings in helicopter. Based on the L-P fatigue life and Hertz contact theory,an mathematical model was established with the combination of Goodman formula,material P-S-N curves and EM modify rule. The friction calorific effect was calculated and the convective heat tranfer coefficient was determined. Then the steady thermal analysis was conducted and the steady maximum temperature under different radial forces and rotate speeds was discussed. Finally the bearing fatigue life was investigated under the effect of thermo-mechanical coupling. The results show that the fatigue life decrease obviously with the operationg temperature raising,so the effect of frictional heating on fatigue life can’t be neglected.

In this work, the adsorption and sensing behavior of Ag-doped MoSe2/ZnO heterojunctions for H2, CH4, CO2, NO, CO, and C2H4 have been studied based on density functional theory (DFT). In gas adsorption analysis, the adsorption energy, adsorption distance, transfer charge, total electron density, density of states (DOS), energy band structure, frontier molecular orbital, and work function (WF) of each gas has been calculated. Furthermore, the reusability and stability of the Ag-doped MoSe2/ZnO heterojunctions have also been studied. The results showed that Ag-doped MoSe2/ZnO heterojunctions have great potential to be a candidate of highly selective and responsive gas sensors for NO detection with excellent reusability and stability. [ABSTRACT FROM AUTHOR]

The provision of high-quality basic public services for people with disabilities contributes to enhancing the level of social security, safeguarding their basic rights to survival and development. It represents an important aspect of achieving "sustainable" poverty reduction in the post-poverty era. Taking Tianjin City as an example, based on measurements of the multidimensional poverty levels among people with disabilities and the accessibility of public service facilities, a coupling coordination model was employed to explore the coupling distribution characteristics of accessibility of public services facilities for people with disabilities and multidimensional poverty at the street level. The results indicate that both the accessibility of public service facilities for people with disabilities and multidimensional poverty exhibit significant urban-rural disparities. Furthermore, there is spatial negative correlation and distinct coupling characteristics between these two factors, with central urban areas and core streets in rural areas serving as central points, respectively showing a decreasing and increasing trend as one moves outward. Finally, based on these findings, differentiated improvement ways and strategies for the allocation of public service facilities in urban and rural areas are proposed. [ABSTRACT FROM AUTHOR]

Comparative analysis of International Standards Organization standard（ ISO） 281: 1990（ the equivalent of GB /T6391- 2003） and ISO 281: 2007（ the equivalent of GB / T6391- 2010） Calculation Method for Rolling Bearing Life was conducted. Differences between the meaning and selection of Life modification factor,as well as their effects on Rolling Bearing Life,were analyzed through calculations. The study indicates that the ISO 281: 2007 introduces the Life modification factor for systems approach,and the factor considers not only the two factors of the ISO 281: 1990 but also the fatigue stress limit of the bearing steel and the contamination in lubricant,which makes it easy and more reliable to estimate the influence of lubrication and contamination on bearing life.