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The discovery of a two-dimensional electron gas (2DEG) at the [Formula: see text] interface has set a new platform for all-oxide electronics which could potentially exhibit the interplay among charge, spin, orbital, superconductivity, ferromagnetism and ferroelectricity. In this work, by using angle-resolved photoemission spectroscopy and conductivity measurement, we found the reduction of 2DEGs and the changes of the conductivity nature of some ferroelectric oxides including insulating Nb-lightly-substituted [Formula: see text], [Formula: see text] (BTO) and (Ca,Zr)-doped BTO across paraelectric-ferroelectric transition. We propose that these behaviours could be due to the increase of space-charge screening potential at the 2DEG/ferroelectric regions which is a result of the realignment of ferroelectric polarisation upon light irradiation. This finding suggests an opportunity for controlling the 2DEG at a bare oxide surface (instead of interfacial system) by using both light and ferroelectricity.

A combined classical and quantum mechanical microcavity (CCQMM) model is used to describe the recombination of excitons in an organic light-emitting devices (OLEDs). Different approaches to device optimization, depending on the fluorescence efficiency of the emitter and whether a shaped substrate is used is discussed.

O-GlcNAcylation (O-GlcNAc) is a posttranslational modification that is mediated by O-GlcNAc-transferase (OGT) and reversed by O-GlcNAcase (OGA). Increasing evidence indicates that protein O-GlcNAcylation is increased in various types of cancer. In the present study, we aimed to evaluate the expression and function of both OGT and OGA in bladder cancer cells in vitro and in vivo. Expression data of OGT and OGA at the mRNA level was obtained from the Oncomine database. Effects of OGT and OGA on cell proliferate, invasive, and migratory abilities were assessed using MTT, wound healing, cell invasive assay, and cell cycle analysis. In vivo assay was also performed in nude mice. The results revealed that the expression of OGT in bladder cancer tissues was higher than that of normal tissues, while the OGA level was found to be lower in cancer tissues. We also found that knockdown of OGT could inhibit cell proliferation, migration, invasion, and induce cell cycle arrest, while these are reversed when OGA is inhibited. We also observed that O-GlcNAcylation could promote tumor formation in vivo, compared with a negative control. In summary, this study describes the oncogenic role of O-GlcNAcylation in bladder cancer cells. [ABSTRACT FROM AUTHOR]

Raman spectra of (Mn, Co)-codoped ZnO films were investigated as functions of laser line and temperature. It is shown that the Raman shifts for different phonon modes exhibit redshift with temperature increasing, which can be attributed to the anharmonic effect in the material. Strong resonant Raman spectra of multi-LO phonons were observed as well for the films with the exciting photon energy higher than the direct band gap. Compared with the Raman spectra for ZnO films, the Mn, Co codoping effect on the spectra is revealed by the presence of additional phonon modes at 275 and 642 cm-1 and another intensive phonon mode at around 524 cm-1. With postannealing, Raman intensity of these phonon modes decrease, owing to the incorporation of oxygen into the films. Origins of the different phonon modes in the spectra are discussed as well. [ABSTRACT FROM AUTHOR]

Raman spectra of SrBi4Ti4O15 (SBTi4) thin films were measured as a function of temperature from 80 to 820 K. Below room temperature, no phonon modes were detected between 200 and 815 cm-1, which indicates the existence of a phonon band gap in this material. Differences between the Raman spectra of the thin film and bulk polycrystalline samples are discussed. The asymmetric Raman band at high frequency can be interpreted as the superposition of two main distinct Raman lines. Temperature dependence of the Raman shifts and full widths at half maximum (FWHMs) for the two phonon modes is discussed as well, which provides information about the vibration energy levels within the film. Theoretical fittings of their FWHMs indicate that the higher-energy phonon mode is apparently more anharmonic than the lower one. [ABSTRACT FROM AUTHOR]

The quantum spin Hall (QSH) effect is widely studied as a novel quantum state in condensed matter physics over the past decade. Recently, it is predicted that the transition metal pentatelluride XTe5 (X = Zr, Hf) has a large bandgap in its bulk form and a single layer of XTe5 is a QSH insulator candidate. However, the topological nature of the bulk material is still under debate because it is located close to the phase boundary of a strong topological insulator and a weak topological insulator (WTI). Here, using angle-resolved photoemission spectroscopy and scanning tunneling microscopy (STM)/scanning tunneling spectroscopy, we systematically studied the electronic structures of bulk HfTe5. Both the large bulk bandgaps and conductive edge states in the vicinity of the step edges in HfTe5 were observed, strongly suggesting a WTI phase in bulk HfTe5. Moreover, our STM experiment for the first time reveals the bulk band bending due to the broken symmetry near the step edge, making it an ideal platform for studying the development of edge states in the WTI and QSH insulator. [ABSTRACT FROM AUTHOR]

We present a simple fabrication of FePt and Fe nanocomposite by annealing self-assembled FePt nanoparticles. 5 nm FePt nanoparticles were prepared by simultaneous reduction of platinum acetylacetonate and thermal decomposition of iron pentacarbonyl in the presence of oleic acid and oleylamine as stabilizers. The as-synthesized FePt nanoparticles can self-organize well on a clean SiO/Si substrate and, then, were annealed in a vacuum using a rapid thermal process at different temperatures for 0.5 h. It is found that the annealing temperature plays a key role in determining the final products. The samples annealed at 550 °C and 700 °C consist of a FePt-face-centered-tetragonal (fct) phase with a coercivity of around 1000 and 8800 Oe, respectively, whereas, the samples annealed at 580 °C are composed of two phases: one is the FePt-fct phase and the other is a Fe-body-centered-cubic phase. The hysteresis loop of the sample annealed at 580 °C is also two-phase like with a kink at low field and its coercivity is around 8000 Oe. That indicates that Fe can be segregated from FePt by proper annealing, forming FePt and Fe nanocomposites. © 2004 American Institute of Physics. [ABSTRACT FROM AUTHOR]

Rice planthopper (RPH) populations of Nilaparvata lugens and Sogatella furcifera periodically have erupted across Asia. Predicting RPH population dynamics and identifying their source areas are crucial for the management of these migratory pests in China, but the origins of the migrants to temperate and subtropical regions in China remains unclear. In particular, their early migration to China in March and April have not yet been explored due to a lack of research data available from potential source areas, Central Vietnam and Laos. In this study, we examined the population dynamics and migratory paths of N. lugens and S. furcifera in Vietnam and South China in 2012 and 2013. Trajectory modeling showed that in March and April in 2012 and 2013, RPH emigrated from source areas in Central Vietnam where rice was maturing to the Red River Delta and South China. Early migrants originated from Southern Central Vietnam (14–16°N), but later most were from Northern Central Vietnam (16–19°N). Analysis of meteorological and light-trap data from Hepu in April (1977–2013) using generalized linear models showed that immigration increased with precipitation in Southern Central Vietnam in January, but declined with precipitation in Northern Central Vietnam in January. These results determined that the RPH originate from overwintering areas in Central Vietnam, but not from southernmost areas of Vietnam. Winter precipitation, rather than temperature was the most important factor determining the number of RPH migrants. Based on their similar population dynamics and low population densities in Central Vietnam, we further speculated that RPH migrate to track ephemeral food resources whilst simultaneously avoiding predators. Migrations do not seem to be initiated by interspecific competition, overcrowding or host deterioration. Nevertheless, S. furcifera establishes populations earlier than N. lugens South China, perhaps to compensate for interspecific competition. We provide new information that could assist with forecasting outbreaks and implementing control measures against these migratory pests. [ABSTRACT FROM AUTHOR]

OBJECTIVE: Osteosarcoma is one of the most common malignant bone tumors. The mechanisms of osteosarcoma development and invasion have been studied for periods of time, yet targeted therapy for improving survival has not been well established. Histone lysine methyltransferase NSD2 was frequently overexpressed in multiple types of cancer such as multiple myeloma, stomach and colon cancer, and the overexpression of it usually associated with aggressiveness tumor type. However, the expression status and function of NSD2 are still ambiguous in osteosarcoma. MATERIALS AND METHODS: Here, we evaluate the abnormal expression levels of NSD2 in osteosarcoma samples and cell lines. The higher expression of NSD2 in tumors resulted in a poorer outcome and a worse 5-year overall survival. To investigate the role of NSD2 in osteosarcoma cell proliferation and invasion in vitro, MTT assay, cell cycle distribution, wound healing, transwell assay was performed in relative cell lines, using a recombinant lentivirus expressing NSD2 short hairpin RNA or NSD2 construction. RESULTS: Our results imply that NSD2 promotes osteosarcoma cell proliferation and invasion, and the mechanism was possibly through the suppression of E-cadherin and induction of the epithelial mesenchymal transition, further to proceed invasion of osteosarcoma cells. CONCLUSIONS: NSD2 may work as a novel repression of E-cadherin; therefore, NSD2 has potential as a target of OS therapy. In the future, the monitoring of NSD2 in the serum/plasma from the RNA level may be used as a non-invasive method for selecting patients for target therapy. [ABSTRACT FROM AUTHOR]