Manipulating the ordered oxygen complexes to achieve high strength and ductility in medium-entropy alloys.

Oxygen solute strengthening is an effective strategy to harden alloys, yet, it often deteriorates the ductility. Ordered oxygen complexes (OOCs), a state between random interstitials and oxides, can simultaneously enhance strength and ductility in high-entropy alloys. However, whether this particular strengthening mechanism holds in other alloys and how these OOCs are tailored remain unclear. Herein, we demonstrate that OOCs can be obtained in bcc (body-centered-cubic) Ti-Zr-Nb medium-entropy alloys via adjusting the content of Nb and oxygen. Decreasing the phase stability enhances the degree of (Ti, Zr)-rich chemical short-range orderings, and then favors formation of OOCs after doping oxygen. Moreover, the number density of OOCs increases with oxygen contents in a given alloy, but adding excessive oxygen (>3.0 at.%) causes grain boundary segregation. Consequently, the tensile yield strength is enhanced by ~75% and ductility is substantially improved by ~164% with addition of 3.0 at.% O in the Ti-30Zr-14Nb MEA.

RuO2 electronic structure and lattice strain dual engineering for enhanced acidic oxygen evolution reaction performance.

Developing highly active and durable electrocatalysts for acidic oxygen evolution reaction remains a great challenge due to the sluggish kinetics of the four-electron transfer reaction and severe catalyst dissolution. Here we report an electrochemical lithium intercalation method to improve both the activity and stability of RuO2 for acidic oxygen evolution reaction. The lithium intercalates into the lattice interstices of RuO2, donates electrons and distorts the local structure. Therefore, the Ru valence state is lowered with formation of stable Li-O-Ru local structure, and the Ru-O covalency is weakened, which suppresses the dissolution of Ru, resulting in greatly enhanced durability. Meanwhile, the inherent lattice strain results in the surface structural distortion of LixRuO2 and activates the dangling O atom near the Ru active site as a proton acceptor, which stabilizes the OOH* and dramatically enhances the activity. This work provides an effective strategy to develop highly efficient catalyst towards water splitting.

Telocytes enhanced in vitro decidualization and mesenchymal-epithelial transition in endometrial stromal cells via Wnt/ß-catenin signaling pathway.

Decidualization of endometrial stromal cells (ESCs) is essential for preparing endometrium for embryo implantation. Telocytes (TCs), a novel type of interstitial cell, exist in the female reproductive tract and participate in the pathophysiology of diseases. This study further investigates the hypothesis that TCs, a source of Wnt, modulates decidualization and MET in ESCs. We had observed differential expression of Wnt ligands in primary mice ESCs and TCs by qPCR. TCM-induced decidualization and MET was assessed in ESCs. Changes in markers for decidualization (cyclin-D3, desmin, d/tPRP), stromal cells (N-cadherin), epithelial cells (E-cadherin), and the Wnt/ß-catenin pathway (ß-catenin, FOXO1) were quantified by western blot and RT-PCR. ß-catenin knockdown in ESCs decreased the degree of TCM-induced decidualization and MET, with significantly reversed expression profiles (P < 0.05). This is the first study to show that TCs can enhance decidualization and MET in ESCs through the Wnt/ß-catenin signaling-pathway. Therefore, we describe a promising cell therapy for gynecological conditions and related reproductive problems associated with defective decidualization.

Accessory ovary may be a treatment for infertility: Case report and review of current literatures.

Accessory ovary is a type of ovarian dysplasia, which is often defined as an ovarian tissue placed near and directly connected to the normal ovary or one of ovarian ligaments. It is often asymptomatic, mostly is found or diagnosed at laparotomy, laparoscopy or autopsy. Accessory ovary is often excised during surgery due to its potential malignant behavior. We report a case of endometriosis cyst occurred simultaneously in right side of orthotopic and accessory ovaries, together with torsion 180° of accessory ovarian cyst. Considering that the patient had not given birth and the large size of cysts, exploratory laparotomy was performed. During laparotomy, both site of ovarian cyst have been removed with orthotopic and accessory ovarian tissues preserved. After surgery, a large number of antral follicles were found both in right side of orthotopic and accessory ovaries by ultrasonography. Accessory ovary is considered to have physiological function, and can be preserved as a fertility protection measure for women who have fertility requirements. At present, the definition of ectopic ovary, accessory ovary and supernumerary ovary are very vague and rarely discussed separately. So, we proposed a new way to clarify the concepts of ectopic ovary, accessory ovary and supernumerary ovary. Moreover, we advocated that they should be discussed separately in terms of definition and management measures.

Size- and temperature-dependent Young's modulus and size-dependent thermal expansion coefficient of thin films.

Nanomaterials possess a high surface/volume ratio and surfaces play an essential role in size-dependent material properties. In the present study, nanometer-thick thin films were taken as an ideal system to investigate the surface-induced size- and temperature-dependent Young's modulus and size-dependent thermal expansion coefficient. The surface eigenstress model was further developed with the consideration of thermal expansion, leading to analytic formulas of size- and temperature-dependent Young's modulus, and size-dependent thermal expansion coefficient of thin films. Molecular dynamics (MD) simulations on face-centered cubic (fcc) Ag, Cu, and Ni(001) thin films were conducted at temperatures ranging from 300 K to 600 K. The MD simulation results are perfectly consistent with the theoretical predictions, thereby verifying the theoretical approach. The newly developed surface eigenstress model will be able to attack similar problems in other types of nanomaterials.