Multiferroicity in doped hexagonal LuFeO3

The hexagonal phase of LuFeO3 is a rare example of a multiferroic material possessing a weak ferromagnetic moment, which is predicted to be switchable by an electric field. We stabilize this structure in bulk form though Mn and Sc doping, and determine the complete magnetic and crystallographic structures using neutron-scattering and magnetometry techniques. The ferroelectric P6(3)cm space group is found to be stable over a wide concentration range, ordering antiferromagnetically with Neel temperatures that smoothly increase following the ratio of c to a (c/a) lattice parameters up to 172 K, the highest found in this class of materials to date. The magnetic structure for a range of temperatures and dopings is consistent with recent studies of high quality epitaxial films of pure hexagonal LuFeO3 including a ferromagnetic moment parallel to the ferroelectric axis. We propose a mechanism by which room-temperature multiferroicity could be achieved in this class of materialsopen

Identification of Mechanism Stiffness of Autoeliminating Clearance for Auxiliary Bearing

In this article, a method for identification of equivalent stiffness was proposed based on a genetic algorithm by studying the stiffness characteristics of autoeliminating clearance auxiliary bearing devices (ACABDs) in static condition. Subsequently, the equivalent stiffness damping model and the Hertz contact theory were combined to establish the theoretical equations of the ACABD. Moreover, the linear equivalent model of the ACABD was established to eliminate the influence of contact of the revolute pair on mode shape and mode frequency of the rotor. In addition, simulations and experiments were carried out to verify the effectiveness of the genetic algorithm-based stiffness identification method. The results indicated that the relative errors between the equivalent stiffness in the X and Y directions identified by the linear equivalent model and the theoretical values were 6.22 and 7.19% respectively, demonstrating the feasibility of this identification method

Chemical Constituent Analysis of Ranunculus sceleratus L. Using Ultra-High-Performance Liquid Chromatography Coupled with Quadrupole-Orbitrap High-Resolution Mass Spectrometry

Ranunculus sceleratus L.(RS) has shown various pharmacological effects in traditional Chinese medicine. In our previous study, the positive therapeutic effect on α-naphthylisothiocyanate induced intrahepatic cholestasis in rats was obtained using TianJiu treatment with fresh RS. However, the chemical profile of RS has not been clearly clarified, which impedes the research progress on the therapeutic effect of RS. Herein, an ultra-high performance liquid chromatography coupled with quadrupole Orbitrap high-resolution mass spectrometry (UHPLC-Q-Orbitrap HRMS) method was developed to rapidly separate and identify multiple constituents in the 80% methanol extract of RS. A total of sixty-nine compounds (19 flavonoids, 22 organic acids, 6 coumarins, 4 lignans, 14 nitrogenous compounds, and 4 anthraquinones) were successfully characterized. A total of 12 of these compounds were unambiguously identified by standard samples. Their mass spectrometric fragmentation pathways were investigated. It is worth noting that flavonoids and lignans were identified for the first time in RS. In this study, we successfully provide the first comprehensive report on identifying major chemical constituents in RS by UHPLC-Q-Orbitrap HRMS. The obtained results enrich the RS chemical profile, paving the way for further phytochemical study, quality control, and pharmacological investigation of RS

Engineering self-healing adhesive hydrogels with antioxidant properties for intrauterine adhesion prevention

Intrauterine adhesion (IUA) is the fibrosis within the uterine cavity. It is the second most common cause of female infertility, significantly affecting women's physical and mental health. Current treatment strategies fail to provide a satisfactory therapeutic outcome for IUA patients, leaving an enormous challenge for reproductive science. A self-healing adhesive hydrogel with antioxidant properties will be highly helpful in IUA prevention. In this work, we prepare a series of self-healing hydrogels (P10G15, P10G20, and P10G25) with antioxidant and adhesive properties. Those hydrogels exhibit good self-healing properties and can adapt themselves to different structures. They possess good injectability and fit the shape of the human uterus. Moreover, the hydrogels exhibit good tissue adhesiveness, which is desirable for stable retention and therapeutic efficacy. The in vitro experiments using P10G20 show that the adhesive effectively scavenges ABTS+, DPPH, and hydroxyl radicals, rescuing cells from oxidative stress. In addition, P10G20 offers good hemocompatibility and in vitro and in vivo biocompatibility. Furthermore, P10G20 lowers down the in vivo oxidative stress and prevents IUA with less fibrotic tissue and better endometrial regeneration in the animal model. It can effectively downregulate fibrosis-related transforming growth factor beta 1 (TGF-β1) and vascular endothelial growth factor (VEGF). Altogether, these adhesives may be a good alternative for the clinical treatment of intrauterine adhesion

Discovery of a Novel Class of Bicyclo[3.1.0]hexanylpiperazines as Noncompetitive Neuropeptide Y Y1 Antagonists

A novel class of bicyclo[3.1.0]­hexanylpiperazine neuropeptide Y (NPY) Y1 antagonists has been designed and synthesized. Scatchard binding analysis showed these compounds to be noncompetitive with [¹²⁵I]­PYY binding to the Y1 receptor. The most potent member, 1-((1α,3α,5α,6β)-6-(3-ethoxyphenyl)-3-methylbicyclo[3.1.0]­hexan-6-yl)-4-phenylpiperazine (<b>2</b>) had an IC₅₀ = 62 nM and displayed excellent oral bioavailability in rat (% <i>F</i> po = 80), as well as good brain penetration (B/P ratio = 0.61). In a spontaneous nocturnal feeding study with male Sprague–Dawley rats, <b>2</b> significantly reduced food intake during a 12 h period