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The rare earth alloy Y 2 Co 17 − x Ni x was prepared by a low-cost co-precipitation reduction-diffusion process, and its crystal structure, static magnetic properties, and microscopic morphology were systematically characterized. The effects of Ni doping with different contents on the electromagnetic parameters and wave absorption properties of Y 2 Co 17 − x Ni x /polyurethane(PU) compounds were researched in the frequency range of 0.1–18 GHz. The results show that the static magnetic properties and wave absorption properties change significantly with Ni doping, and the maximum reflection loss of Y 2 Co 14 Ni 3 /PU reaches − 89.7 dB at 2.9 mm thickness, and the maximum reflection loss peaks of Y 2 Co 17 /PU and Y 2 Co 16 Ni 1 /PU are at 1.316 and 1.515 GHz, which is at the center frequency of the L-band. With Ni doping, the effective absorption bandwidth of the compounds at a frequency above 3 GHz is greatly increased. The physical factor in the bandwidth calculation was modified, and the effective absorption bandwidth of the material was calculated theoretically, and the error was less than 5 % compared with the experimental value. [ABSTRACT FROM AUTHOR]

The Janus kinase/signal transducer and activator of the transcription 3 (JAK/STAT3) signaling pathway controls multiple biological processes, including cell survival, proliferation, and differentiation. Abnormally activated STAT3 signaling promotes tumor cell growth, proliferation, and survival, as well as tumor invasion, angiogenesis, and immunosuppression. Hence, JAK/STAT3 signaling has been considered a promising target for antitumor therapy. In this study, a number of ageladine A derivative compounds were synthesized. The most effective of these was found to be compound 25. Our results indicated that compound 25 had the greatest inhibitory effect on the STAT3 luciferase gene reporter. Molecular docking results showed that compound 25 could dock into the STAT3 SH2 structural domain. Western blot assays demonstrated that compound 25 selectively inhibited the phosphorylation of STAT3 on the Tyr705 residue, thereby reducing STAT3 downstream gene expression without affecting the expression of the upstream proteins, p-STAT1 and p-STAT5. Compound 25 also suppressed the proliferation and migration of A549 and DU145 cells. Finally, in vivo research revealed that 10 mg/kg of compound 25 effectively inhibited the growth of A549 xenograft tumors with persistent STAT3 activation without causing significant weight loss. These results clearly indicate that compound 25 could be a potential antitumor agent by inhibiting STAT3 activation. [ABSTRACT FROM AUTHOR]

Aims: To determine deficiencies in the Food and Drug Administration (FDA)'s guidance for assessing acarbose bioequivalence (BE) and to explore optimal pharmacodynamic (PD) metrics for better evaluation of acarbose BE. Methods: Three clinical trials with branded acarbose were conducted in healthy subjects, including a pilot study (Study I, n = 11, 50 and 100 mg), a 2×2 crossover BE study (Study II, n = 36, 100 mg) and a 4×4 Williams study (Study III, n = 16, 50/100/150 mg). Serum glucose concentrations were measured by the glucose oxidase method. Results: In Study I, compared with 50 mg acarbose, only 100 mg acarbose had a significantly lower Cmax0–4h than that of sucrose administration alone (7.96 ± 0.83 mmol/L vs 6.78 ± 1.02 mmol/L, P <.05). In Study II, the geometric mean ratios of the test formulation to the reference formulation (both formulations were the branded drug) for FDA PD metrics, ΔCmax0–4h and ΔAUC0–4h, were 0.903 and 0.776, respectively, and the 90% confidence intervals were 67.44–120.90 and 53.65–112.13, respectively. The geometric mean ratios (confidence interval) for possible optimal evaluation PD metrics (Cmax0–2h and AUC0–2h) were 1.035 (94.23–112.68) and 0.982 (89.28–107.17), respectively. Further, Cmax0–2h and AUC0–2h also met the sensitivity requirements for BE evaluation in Study III. Conclusion: Considering the mechanisms of action of acarbose, the PD effect was shown to be dose independent during the 2–4 hours postadministration of acarbose. Hence PD metrics based on the serum glucose concentration from 0 to 2 hours (Cmax0–2h and AUC0–2h) are more sensitive than the FDA‐recommended PD metrics for acarbose BE evaluation from 0–4 hours (ΔCmax0–4h and ΔAUC0–4h). The trial has been registered at the Chinese Clinical Trial Registry (http://www.chictr.org.cn, ChiCTR1800015795, ChiCTR‐IIR‐17013918, ChiCTR‐IIR‐17011903). All subjects provided written informed consent before screening. [ABSTRACT FROM AUTHOR]

Significant electric control of exchange bias effect in a simple CoO1–δ/Co system, grown on piezoelectric Pb(Mg1/3Nb2/3)0.7Ti0.3O3 (110) (PMN-PT) substrates, is achieved at room temperature. Obvious changes in both the coercivity field (HC) and the exchange bias field (HE), of 31% and 5%, respectively, have been observed when the electric field is applied to the substrate. While the change of coercivity is related to the enhanced uniaxial anisotropy in the ferromagnetic layer, the change of the exchange bias field can only originate from the spin reorientation in the antiferromagnetic CoO1–δ layer caused by the strain-induced magnetoelastic effect. A large HE/HC > 2, and HE ∼ 110 Oe at room temperature, as well as the low-energy fabrication of this system, make it a practical system for spintronic device applications. [ABSTRACT FROM AUTHOR]

Poly (butylene succinate-co-butylene-3-hydroxyphenylphosphinyl-propionate) (PBSH) was synthesized through polycondensation. Then, 4,4′-methylene diphenyl diisocyanate (MDI) was introduced into PBSH matrix by reactive blending. The chemical structure and properties of the blending products were investigated using Fourier Transform Infrared Spectroscopy (FT-IR), differential scanning calorimetry (DSC), limiting oxygen index (LOI) tests, thermogravimetric analysis (TGA), and vertical burning tests. The results proved that MDI can improve the mechanical properties and flame retardancy of PBSH. In addition, it was found that the crosslinking structure can reduce the hydrolysis rate of PBSH and effectively eliminate the melt-dripping of PBSH during combustion. [ABSTRACT FROM AUTHOR]

Neutron diffraction technology as an advanced material research technique has special advantages in studying magnetic materials compared to the conventional techniques such as X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), and X-ray photoelectron spectroscopy (XPS). In this review, the applications of neutron diffraction technology on permanent magnetic materials were briefly reviewed: (1) the determination of the crystal structure and magnetic structure of the typical permanent magnet material, (2) in situ neutron diffraction study of the crystal structure evolution of the permanent magnets, and (3) phase transition in permanent magnetic materials. [ABSTRACT FROM AUTHOR]

Material research on perovskite-type oxides (ABO3) has been driven by the recognition of their unique properties primarily attributed to the presence of oxygen octahedron (BO6). Since 2003, the discovery of strong coupling in TbMnO3 and BiFeO3 has stimulated new interests in understanding the relationship between magnetic and electric properties in perovskites. In this article, we report our recent work on the magnetic superexchange interaction and charge formation in copper-doped LaFeO3 using high-temperature neutron diffraction and thermoelectric measurements. In situ neutron diffraction measurements show a loss of antiferromagnetic ordering above 450°C. With an increase in Cu content, the (Fe, Cu)-O bond length decreases and the (Fe, Cu)-O-(Fe, Cu) bond angle increases, which leads to an enhancement of the Fe-O-Fe superexchange interaction. Thermoelectric and electrical measurements show that the formation of electron holes in Cu-doped LaFeO3 is a thermally activated process with two distinct regions with a transition temperature near 450°C, in congruence with the magnetic measurements. Our work show that Cu is in 3+ state in La(Fe,Cu)O3 at room temperature, resulting in the maximum superexchange interaction between Fe3+ ions. [ABSTRACT FROM AUTHOR]

Adopting the tortoise coordinates transformation in the advanced Eddington coordinates and applying the generalized law of thermodynamics, we discuss the corrected entropy of a general spherically symmetric black hole beyond the semi-classical limit. We give the corrections to the Bekenstein-Hawking area law following from the modified Hawking temperature. Two examples are explicitly worked out. The conclusion is that the corrected entropy includes a logarithmically term and an inverse term to the Bekenstein-Hawking entropy, which is the same form as that of the static and the stationary black holes discussed by using the loop quantum gravity and the string theory. [ABSTRACT FROM AUTHOR]

Abstract: The effects of Ga and Ti substitutions for Sn on the Mn spin arrangements in the YMn6Sn6 compound have been investigated by means of X-ray diffraction (XRD), magnetization measurement and Mössbauer spectroscopy. XRD refinement indicates that Ga and Ti atoms prefer to occupy 2d and 2e sites, respectively. Mössbauer spectra indicate incommensurate magnetic structures for the YMn6Sn6, YMn6Sn5.4Ga0.6 and YMn6Sn5.4Ti0.6 compounds. The substitution of Ga for Sn at the 2d sites is found to significantly decrease the turn angle in the Mn–Sn3–Sn2–Sn3–Mn layer and to subsequently increase the net magnetization. On the other hand, the substitution of Ti for Sn at 2e sites increases the turn angles in the Mn–(Y,Sn1)–Mn and Mn–Sn3–Sn2–Sn3–Mn layers, and consequently decreases the exchange coupling of Mn–Mn between different layers. The resulting ferromagnetic and ferrimagnetic behavior, as has been observed for YMn6Sn5.4Ga0.6 and YMn6Sn5.4Ti0.6, respectively, can be explained in terms of these spin interactions. [Copyright &y& Elsevier]

Textured Bi and MnBi/Bi thin films are prepared by the pulsed laser deposition method. The highly c-axis textured MnBi films are obtained by annealing the bilayer consisting of textured Bi and Mn films. The coercivities of the MnBi/Bi film are 1.5 T and 2.35 T at room temperature and at 373 K, respectively, showing a positive temperature coefficient. Microstructural investigations show that the textured MnBi film results from the orientated growth induced by the textured Bi under-layer. [ABSTRACT FROM AUTHOR]