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We report a comprehensive study of the Zr 5 Pt 3 C x superconductors, with interstitial carbon between 0 and 0.3. At a macroscopic level, their superconductivity, with T c ranging from 4.5 to 6.3 K, was investigated via electricalresistivity, magnetic-susceptibility, and specific-heat measurements. The upper critical fields μ 0 H c2 ∼ 7 T were determined mostly from measurements of the electrical resistivity in applied magnetic field. The microscopic electronic properties were investigated by means of muon-spin rotation and relaxation (μSR) and nuclear magnetic resonance (NMR) techniques. In the normal state, NMR relaxation data indicate an almost ideal metallic behavior, confirmed by band-structure calculations, which suggest a relatively high electronic density of states at the Fermi level, dominated by the Zr 4d orbitals. The low-temperature superfluid density, obtained via transverse-field μSR, suggests a fully gapped superconducting state in Zr 5 Pt 3 and Zr 5 Pt 3 C 0.3 , with zerotemperature gap 0 = 1.20 and 0.60 meV and magnetic penetration depth λ 0 = 333 and 493 nm, respectively. The exponential dependence of the NMR relaxation rates below T c further supports nodeless superconductivity. The absence of spontaneous magnetic fields below the onset of superconductivity, as determined from zero-field μSR measurements, confirms the preserved time-reversal symmetry in the superconducting state of Zr 5 Pt 3 C x . In contrast to a previous study, our μSR and NMR results suggest conventional superconductivity in the Zr 5 Pt 3 C x family, independent of the C content.

We report a study of the noncentrosymmetric TaReSi superconductor by means of the muon-spin rotation and relaxation (μSR) technique, complemented by electronic band-structure calculations. Its superconductivity, with T c = 5.5 K and upper critical field μ 0 H c2 (0) ∼ 3.4 T, was characterized via electrical-resistivity and magneticsusceptibility measurements. The temperature-dependent superfluid density, obtained from transverse-field μSR, suggests a fully gapped superconducting state in TaReSi, with an energy gap 0 = 0.79 meV and a magnetic penetration depth λ 0 = 562 nm. The absence of a spontaneous magnetization below T c , as confirmed by zerofield μSR, indicates a preserved time-reversal symmetry in the superconducting state. The density of states near the Fermi level is dominated by the Ta-and Re-5d orbitals, which account for the relatively large band splitting due to the antisymmetric spin-orbit coupling. In its normal state, TaReSi behaves as a three-dimensional Kramers nodal-line semimetal, characterized by an hourglass-shaped dispersion protected by glide reflection. By combining nontrivial electronic bands with intrinsic superconductivity, TaReSi is a promising material for investigating the topological aspects of noncentrosymmetric superconductors.

tumors in BALB/c nude mice, the radiosensitizing effect of PD98059 was investigated in vivo. Results: Our study found the delayed xenograft tumor growth in PDAC was significantly inhibited by fractionated radiation, while reactivated after the radiotherapy ended, inducing tumor relapse. The Mek kinase inhibitor PD98059 significantly radiosensitized PDAC cell lines by enhancing DSBs and inhibiting DNA damage repair, resulting in decreased clonogenic survival and increased tumor growth inhibitory effect. In vivo studies showed PD98059 significanlty delayed xenograft tumor growth with decreased tumor weight and prolonged tumor growth delay time. Conclusion: Our study discovered targeting MAPK signaling pathway could significantly improve tumor radioresponse of PDAC.

We experimentally demonstrate the spatially multiplexed picosecond pulse-train generations based on the intramodal multiple four-wave mixings in a km-long graded-index multimode fiber.