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Deep faults significantly impact the structural stabilities and deformation behaviors of their overburden rocks, which are key factors in underground engineering and geological hazard research. Considering the problem of deep-fault-overburdened breaking during mining of super-thick coal seams and taking the Yaoqiao Coal Mine as the research object, the mining fracture evolution characteristics and overburden displacement law of the non-structured and fault-bearing overburden corresponding to fully mechanized caving mining are compared and analyzed using numerical simulations and physical similarity simulations. The results of this study show the following: 1) The fracture height of the overlying rock presents a specific change law with advancement of the working face; the initial rapid increase to a maximum height of 74 m is achieved when the working face advances to 90 m; with the development of the plastic zone indicating past yield, the fracture height decreases to 54 m and becomes stable, and the final caving angle of the fracture stabilizes at 70°. 2) In coal mining under normal fault conditions, when the working face advances from the upper to lower walls, the roof forms a masonry beam structure that slows down fault activation and crack development. When moving away from the fault, the overburden movements and water-conducting cracks are fewer, and the crack height is lower than that without faults. When approaching the fault, the influence of the faults in the fracture zone increases, and the height of fracture development reaches the maximum value after crossing the fault, highlighting the significant influence of the fault on fracture development. 3) Through a similarity simulation test, it is shown that the overburden caving zone is further compacted by the overburden rock and that the roof collapses in a large range, resulting in rapid upward development of the overburden rock cracks and separation of the central overburden rock cracks that are gradually compacted and closed. These findings are expected to have important theoretical and practical significance for deep underground engineering design, geological disaster prevention, and fault activity monitoring. [ABSTRACT FROM AUTHOR]

Halide perovskite nanocrystals are innovative luminescent materials for fluorescent probes with high quantum yield and narrow emission bandwidth. However, the limited stability, single-signal response, and separation challenges obstruct their widespread use in water ion detection. Herein, a ratiometric fluorescence sensor based on terbium alginate gel beads (green fluorescent, namely Tb-AG) embedded with powdered CsPbI3@Pb-MOF (red fluorescent) was prepared for fluorescent determination and adsorption of Fe3+. Pb-MOF's protection notably enhances the water stability of CsPbI3, while the energy transfer between CsPbI3@Pb-MOF and Tb3+ elevates the optical performance of CsPbI3@Pb-MOF@Tb-AG. Significantly, Fe3+ markedly suppresses CsPbI3@Pb-MOF red fluorescence at 647 nm, while not noticeably affecting Tb-AG green emission at 528 nm. The sensor exhibited a strong linear response to Fe3+ concentrations ranging from 0 to 90 μM, with a detection limit of 0.44 μM and high selectivity. The CsPbI3@Pb-MOF@Tb-AG-based sensor has been effectively validated through its successful use in detecting Fe3+ in tap and river water samples. Furthermore, CsPbI3@Pb-MOF@Tb-AG demonstrates a notable adsorption capacity of 325.4 mg g−1 Fe3+. Finally, the mechanism of Fe3+ detection and adsorption was determined. [ABSTRACT FROM AUTHOR]

Strongly confined electromagnetic (EM) fields generated by tightly focused light beams are applied widely in nano‐optics due to their vectorial characteristics. The inclusion of the longitudinal polarized component plays a crucial role in both the physical characteristics and practical uses of tightly focused vector beams. The acquisition of the distributions of the three orthogonal polarized components of these fields is advantageous for the comprehensive examination of their captivating physical phenomena and possible applications. However, this continues to pose a noteworthy obstacle, especially in the case of the fields that are generated by high numerical aperture objectives. A novel approach is proposed to quantifying the three mutually perpendicular polarizations simultaneously in the focal plane. The method utilizes a dual‐mode waveguide probe that is composed of a dielectric nanoparticle and a metal‐dielectric waveguide. This design allows for the simultaneous support of both transverse electric (TE) and transverse magnetic (TM) modes. Consequently, it enables the polarization recognition of scattering light in k‐space. Importantly, this method effectively eliminates any interference originating from the background light. The work involves an analysis of the theoretical notion of the probe and followed by experimental investigations. This approach holds promise for augmenting optical nanoscopy methodologies and their associated applications. [ABSTRACT FROM AUTHOR]

The photocatalytic degradation of tetracycline hydrochloride (TCH) under high salinity poses a significant challenge due to the inhibitory effect of coexisting ions on reactive oxygen species in wastewater. Herein, a series of hierarchically porous Z-scheme CsPbBr3@HZIF-8 heterojunctions were synthesized by a sequential deposition method. Benefiting from the stable hierarchical pore structure of HZIF-8 and the excellent optoelectronic properties of CsPbBr3, the hierarchical pore Z-scheme heterojunction CsPbBr3@HZIF-8 not only facilitates the mass transfer and enrichment of pollutants but also accelerates the transfer of carriers between HZIF-8 and CsPbBr3, leading to enhanced generation of reactive oxygen species. Moreover, CsPbBr3 serves as a photosensitizer for energy transfer, generating singlet oxygen (1O2) with higher resistance to ion interference. As a result, the 4%-CsPbBr3@HZIF-8 achieved the highest visible light degradation efficiency of TCH (94% in 40 min), surpassing those of most reported CsPbBr3-based photocatalysts. The catalytic system consistently degrades contaminants in deionized water, high ion concentrations, and real water matrices. The photocatalytic reaction mechanisms, involving charge carrier transfer, reactive species generation, and TCH degradation intermediate products, are thoroughly investigated. [ABSTRACT FROM AUTHOR]

Photonic spin skyrmions with deep‐subwavelength features have aroused considerable interest in recent years. However, the manipulation of spin structure in the skyrmions in a desired manner is still a challenge, while this is crucial for developing the skyrmion‐based applications. Here, an approach of optical spin manipulation by utilizing the spin‐momentum equation is proposed to investigate the spin texture in a photonic skyrmion‐pair. With the benefit of the proposed approach, a unique spin texture with spin angular momentum varying linearly along the line connecting the two skyrmion centers is theoretically designed and experimentally verified. The optimized spin texture is then applied in a displacement‐sensing system, which is capable of attaining pico‐metric sensitivity. Compared with the conventional polarization and phase schemes, the spin‐based manipulation mechanism provides a new pathway for optical modulation, which is of great value in nanophotonics from both fundamental and application. [ABSTRACT FROM AUTHOR]

We study the focusing nonlinear Schrödinger equation with inverse-square potential i ∂ t u + Δ u − a | x | 2 u + | u | p − 1 u = 0 with a > − 1 4 and 3 4 < p − 1 < 4 in three dimensions. In this paper we obtain blow-up and global existence criteria for the solution to ( N L S a ) by the method from Duyckaerts-Roudenko [1], which extend a recent work of Killip-Murphy-Visan-Zheng [2] to above the threshold. [ABSTRACT FROM AUTHOR]

We study the focusing inhomogeneous nonlinear Schrödinger equation with inverse‐square potential i∂tu+Δu−a|x|2u+|x|−b|u|2u=0,$$ i{\partial}_tu&amp;#x0002B;\Delta u-\frac{a}{{\left&amp;#x0007C;x\right&amp;#x0007C;}&amp;#x0005E;2}u&amp;#x0002B;{\left&amp;#x0007C;x\right&amp;#x0007C;}&amp;#x0005E;{-b}{\left&amp;#x0007C;u\right&amp;#x0007C;}&amp;#x0005E;2u&amp;#x0003D;0, $$where a>−14$$ a&gt;-\frac{1}{4} $$ and 0

We revisit the scattering result below the ground state of Y. Gao and H. Wu [Scattering for the focusing H ˙ 1 2 -critical Hartree equation in energy space. Nonlinear Anal. 2010;73:1043–1056] on the radial focusing energy-subcritical Hartree equation in d = 5, using the method in Dodson and Murphy [A new proof of scattering below the ground state for the 3D radial focusing cubic NLS. preprint, arXiv:1712.09962]. Using the radial Sobolev embedding and a virial-Morawetz type estimate we can exclude the concentration of mass near the origin instead of using the concentration compactness method in Gao and Wu [Scattering for the focusing H ˙ 1 2 -critical Hartree equation in energy space. Nonlinear Anal. 2010;73:1043–1056]. [ABSTRACT FROM AUTHOR]

The stability of the surrounding rock in the goaf is one of the main factors to ensure the safety of the mining production. In this study, a coupled numerical simulation model of particle flow code, computational fluid dynamics, and parallel-bounded stress corrosion (PFC-CFD-PSC model) was proposed to conduct the seepage-creep coupling simulation through PFC 5.0 software. Based on the mechanical results, the crack propagation law of the coal measure sandstone under the mining-induced seepage-creep coupling load was analyzed, and the distribution of pressure gradient in the fluid grid was studied. The results show that seepage pressure has a significant effect on the damage of the rock mass; the greater the seepage pressure on the coal measure sandstone model, the more penetration cracks are generated and the greater the degree of macroscopic damage. When the residual strength is 70% of the peak strength, the damage degree of the coal measure sandstone increases with the increase of the seepage pressure; except for the four corners, the pressure gradient of the fluid at the top of the rock mass model is relatively large. The maximum value of the fluid grid pressure gradient increases with the increasing seepage pressure; it increases slowly under the seepage pressure of less than 1.5 MPa and increases sharply under the seepage pressure of greater than 1.5 MPa. [ABSTRACT FROM AUTHOR]

aimed to reveal the correlation of mutational and evolutionary traits with clinical outcomes. Methods: We applied a case-based targeted and whole exome sequencing of eleven matched primary, recurrent and metastatic samples from three OS patients characterized by different clinical behaviors in local recurrence or systematic progression pattern. Results: Extensive OS-associated driver genes were detected including TP53, RB1, NF1, PTEN, SPEN, CDKN2A. Oncogenic signaling pathways including cell cycle, TP53, MYC, Notch, WNT, RTK-RAS and PI3K were determined. MYC amplification was observed in the patient with shortest disease-free interval. Linear, branched or mixed evolutionary models were constructed in the three OS cases. A branched evolution with limited root mutation was detected in patient with shorter survival interval. ADAM17 mutation and HEY1 amplification were identified in OS happening dedifferentiation. Signatures 21 associated with microsatellite instability (MSI) was identified in OS patient with extra-pulmonary metastases. Conclusion: OS was characterized by complex genomic alterations. MYC aberration, limited root mutations, and a branched evolutionary model were observed in OS patient with relatively aggressive course. Extra-pulmonary metastases of OS might attribute to distinct mutational process pertaining to MSI. Further research in a larger number of people is needed to confirm these findings. [ABSTRACT FROM AUTHOR]

Abstract Background Wide use of ciprofloxacin and levofloxacin has often led to increased resistance. The resistance rate to these two agents varies in different clinical isolates of Enterobacteriaceae. Mutations of GyrA within the quinolone resistance-determining regions have been found to be the main mechanism for quinolone resistance in Enterobacteriaceae. It has been shown that only some of the mutations in the gyrA gene identified from clinical sources were involved in fluoroquinolone resistance. Whether different patterns of gyrA mutation are related to antimicrobial resistance against ciprofloxacin and levofloxacin is unclear. Methods The minimum inhibitory concentration (MIC) of ciprofloxacin and levofloxacin were determined by the agar dilution method followed by PCR amplification and sequencing of the quinolone resistance determining region of gyrA to identify all the mutation types. The correlation between fluoroquinolone resistance and the individual mutation type was analyzed. Results Resistance differences between ciprofloxacin and levofloxacin were found in 327 isolates of K. pneumoniae and E. coli in Harbin, China and in the isolates reported in PubMed publications. GyrA mutations were found in both susceptible and resistant isolates. For the isolates with QRDR mutations, the resistance rates to ciprofloxacin and levofloxacin were also statistically different. Among the 14 patterns of alterations, two single mutations (Ser83Tyr and Ser83Ile), and three double mutations (Ser83Leu+Asp87Asn, Ser83Leu+Asp87Tyr and Ser83Phe+Asp87Asn) were associated with both ciprofloxacin and levofloxacin resistance. Two single mutations (Ser83Phe and Ser83Leu) were related with ciprofloxacin resistance but not to levofloxacin. Resistance difference between ciprofloxacin and levofloxacin in isolates harboring mutation Ser83Leu+Asp87Asn were of statistical significance among all Enterobacteriaceae (P Conclusions Resistance rate to ciprofloxacin and levofloxacin were statistically different among clinical isolates of Enterobacteriaceae harboring GyrA mutations. Ser83Leu+Asp87Asn may account for the antimicrobial resistance difference between ciprofloxacin and levofloxacin.