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Magnetic properties of hexagonal YMnO3 nanoparticles were systematically investigated. It is found that zero-field cooled and field-cooled magnetization display divergences at low temperature and a spin-glass temperature of TSG of 43 K are undergone. The thermoremanent magnetization further confirms the spin-glass feature of the YMnO3, which is related to the surface effects resulting in uncompensated spin and suppression of antiferromagnetic order. In particular, the exchange-bias effect is attributed to an exchange coupling between an antiferromagnetic core and the spin-glassy shell or ferromagnetic surface spins of the nanoparticles, which depends on the cooling field, is very interesting for nanomagnetic devices applications. [ABSTRACT FROM AUTHOR]

Tectonic controls on near-surface CH4 and CO2 concentrations were investigated by measuring CH4 and CO2 concentrations at the surface and a height of 1.5 m, in the different tectonic units that comprise the northwestern margin of Ordos Block, China, which has a complex tectonic structure and a history of strong earthquakes. CH4 and CO2 concentrations varied from 1905 to 2472 ppb and 397.5 to 458.5 ppm, respectively. Surface CH4 and CO2 concentrations were generally higher than those measured at 1.5 m, but showed similar trends, indicating that the measured CH4 and CO2 predominantly originated from underground gases. The CH4 and CO2 concentrations increased with an increasing strike-slip rate across the faults, and concentrations in the blocks with high internal deformation were much higher than those measured in the stable blocks. Regions of extensional deformation had higher gas concentrations than regions that had experienced compressional deformation. The spatial distribution of CH4 and CO2 at the study site had similar trends to faults associated with the Yinchuan Graben. The results of this study indicated that gas source, gas migration pathway, and tectonic stress were the main factors that influenced gas emission. The key factor is tectonic stress, which controlled the formation of tectonic structures, changed the pathway of degassing, and acted as the driving force for gas migration. The results of this study clarify the mechanism of CH4 and CO2 degassing in faulted regions and suggest that CH4 and CO2 concentrations may be useful precursors in the monitoring of seismic activity. The results may also help inform future assessments of the contribution of geological sources to greenhouse gas emissions. [ABSTRACT FROM AUTHOR]

OBJECTIVE: To explore the role of microRNA-203 in laryngeal cancer and its underlying mechanism in regulating cell invasion and apoptosis. PATIENTS AND METHODS: MicroRNA-203 expression in laryngeal cancer tissues and paracancerous tissues was detected by quantitative real time-polymerase chain reaction (qRTPCR). The regulatory effects of microRNA-203 on the invasion and apoptosis of laryngeal cancer cells were detected by transwell assay and flow cytometry, respectively. Dual-Luciferase reporter gene assay was performed to access the binding condition of microRNA-203 and LASP1. Both mRNA and protein levels of LASP1 in laryngeal cancer cells were detected after transfection with microRNA-203 mimic or microRNA-203 inhibitor by qRT-PCR and Western blot, respectively. Rescue experiments were finally performed to detect whether microRNA-203 regulates laryngeal cancer development via targeting LASP1. RESULTS: MicroRNA-203 was lowly expressed in laryngeal cancer tissues and cell lines. MicroRNA-203 knockdown in Hep-2 cells can promote the invasion and inhibit the apoptosis of laryngeal cancer cells. Subsequently, LASP1 was predicted to be the target gene of microRNA-203, which was further verified by the Dual-Luciferase reporter gene assay. LASP1 expression was negatively regulated by microRNA-203. Furthermore, rescue experiments showed that the regulatory effects of microRNA-203 on the invasion and apoptosis of laryngeal cancer cells were reversed by LASP1. CONCLUSIONS: We showed that lowly expressed microRNA-203 could promote the invasion and inhibit apoptosis of laryngeal cancer cells via inhibiting LASP1. [ABSTRACT FROM AUTHOR]

Herein, the photovoltaic (PV) effect of ferroelectric Bi0.85La0.15FeO3 (BLFO) films fabricated through a sol–gel method is investigated. The ferroelectric properties of the BLFO films improve compared to the undoped BiFeO3 films. The application of Au nanoparticles (AuNPs) increases the open circuit voltage (VOC) and short circuit current density (JSC) from 0.2 V to 0.3 V and 5.3 μA cm−2 to 18.5 μA cm−2, respectively, which could be attributed to Au surface-plasmon effects. The PV output for the BLFO film can be modulated after applying external poling voltages. Considering the ferroelectric polarization and plasmonic effects, a plausible theoretical model is constructed to depict the physical mechanism of PV enhancement for the BLFO film in detail. This work not only presents a new approach to improve the PV effect of ferroelectric films but also provides important insights into the PV mechanism of ferroelectric films. [ABSTRACT FROM AUTHOR]