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By applying an electric field parallel to the substrate surface, highly ordered Ag nanoparticles were homogeneously embedded in BaTiO3 (BTO) films grown on a MgO(100) substrate. Transmission electron microscopy studies show that the BTO film is [100]-oriented. The general crystallographic orientation relationships between the composite film and MgO substrate are [100]BTO//[100]Ag//[100]MgO and (010)BTO//(010)Ag//(010)MgO. However, in films grown without an external electric field, Ag particles grow with random orientations and the BTO matrix is polycrystalline. Thus, electric fields are thought to meliorate the quality of the films by changing the growth orientation. In addition, the BTO matrix and Ag particles were found to be multiply twinned from studies on cross-sectional specimens. The contribution is discussed of Ag particles with ordered growth orientation and the large amount of BTO microtwins with higher dielectric constant to the improved optical properties of the as-prepared composite films. [ABSTRACT FROM AUTHOR]

The microstructural characteristics of misfit dislocations at the interface between La 0.9 Sr 0.1 MnO 3 films and vicinal SrTiO 3 substrates have been studied by transmission electron microscopy. The misfit dislocations were determined to be edge type with Burgers vector Owing to the inclination of the substrate, the dislocation line along the miscut direction of the substrate is rotated. The deviation angle of the dislocation line away from the miscut direction of the substrate varies with the miscut angle. As a result, the dislocation arrays at the interface form a parallelogram dislocation network rather than an orthogonal network. A simple explanation of the misfit dislocation reaction with the step for the film on a vicinal substrate is proposed to interpret the rotation of the dislocation line along the miscut direction. [ABSTRACT FROM AUTHOR]

Thin films of orthorhombic La0.9Sr0.1MnO3, have been grown by computer-controlled laser molecular-beam epitaxy on SrTiO3(001) substrate and vicinal SrTiO3(001) substrates. Electron diffractions and high-resolution imaging reveal that the as-received thin films with thickness of 300 nm are epitaxially grown on the substrates. The microstructures in the film grown on SrTiO3(001) substrate are clarified in terms of the oriented microdomains, while the films on vicinal SrTiO3(001) substrates are predominated by a single [101]-oriented growth, which provides a useful routine for a design of preferred physical properties. Based on the minimization of surface energy, the mechanism of such a single domain formation is proposed. [ABSTRACT FROM AUTHOR]

We report ferroelectric (FE), ferromagnetic, and magnetoelectric (ME) properties of BiFeO3 films directly deposited on flexible magnetic Ni tapes. Without use of metal-oxide and/or noble metal buffer layer between the BiFeO3 and the Ni, both ferroelectric and magnetic properties of the film and the substrate are preserved. X-ray diffraction and transmission electron microscopy analyses confirm the formation of preferentially oriented (110) BiFeO3 film on Ni tapes. The BiFeO3 film has a saturation polarization and a piezoelectric d33 coefficient of 69 μC/cm2 and 52 pm/V, respectively. The BiFeO3/Ni tape shows a magnetoelectric coefficient of 3.5 mV/cm·Oe. [ABSTRACT FROM AUTHOR]

Investigation of molecular and cellular mechanisms of synaptic plasticity is the major focus of many neuroscientists. There are two major reasons for searching new genes and molecules contributing to central plasticity: first, it provides basic neural mechanism for learning and memory, a key function of the brain; second, it provides new targets for treating brain-related disease. Here, I propose that LTP in the anterior cingulate cortex (ACC) as a synaptic model for emotional fear and chronic pain in the brain. Integrative approaches including genetic, neurobiological and physiological methods are used to investigate the roles of cortical neurons and microglia in synaptic LTP, fear and chronic pain. We have identified several key calcium-stimulated signaling molecules including AC1, CaMKIV and FMRP for AMPA receptor mediated cingulate LTP, trace fear memory, and chronic pain. By contrast, microglia only contributes to changes in spinal dorsal horn, but not in the cortex. Our findings strongly suggest that ACC LTP may serve as a cellular model for studying central sensitization that related to fear and chronic pain, as well as pain-related cognitive emotional disorders. [Copyright &y& Elsevier]

The anterior cingulate cortex (ACC) plays an important role in higher brain functions including learning, memory, and persistent pain. Long-term potentiation of excitatory synaptic transmission has been observed in the ACC after digit amputation, which might contribute to plastic changes associated with the phantom pain. Here we report a long lasting membrane potential depolarization in ACC neurons of adult rats after digit amputation in vivo. Shortly after digit amputation of the hind paw, the membrane potential of intracellularly recorded ACC neurons quickly depolarized from ∼-70 mV to ∼-15 mV and then slowly repolarized. The duration of this amputation-induced depolarization was about 40 min. Intracellular staining revealed that these neurons were pyramidal neurons in the ACC. The depolarization is activity-dependent, since peripheral application of lidocaine significantly reduced it. Furthermore, the depolarization was significantly reduced by a NMDA receptor antagonist MK-801. Our results provide direct in vivo electrophysiological evidence that ACC pyramidal cells undergo rapid and prolonged depolarization after digit amputation, and the amputation-induced depolarization in ACC neurons might be associated with the synaptic mechanisms for phantom pain. [ABSTRACT FROM AUTHOR]

We report herein the identification of 23 novel Mafa-B alleles in cynomolgus macaques of Vietnamese origin. [ABSTRACT FROM AUTHOR]

We report here the identification of one Mafa- DPA1 and four Mafa- DQB1 novel alleles of Vietnamese cynomolgus macaques. [ABSTRACT FROM AUTHOR]

Unlike metal electrodes such as Al and Au, aluminum doped zinc oxide (AZO) with high conductivity and transparency can be used as transparent electrodes for surface acoustic wave (SAW) resonators, and thus realize fully transparent and invisible ZnO SAW devices on glass. This paper reports the fabrication of transparent SAW resonators using AZO as the transparent electrode and investigation of effects of deposition parameters on the crystal structures of the AZO thin films deposited by magnetron sputtering. Results show that a low sputtering pressure and an optimal sputtering power are beneficial for the deposition of (0002) orientation of AZO. The optimal deposition parameters are found to be: deposition pressure of 0.3 Pa, sputtering power of 300 W, substrate temperature of 200 °C. The fabricated transparent SAW devices have different wavelengths (from 16 to 32 μm) and all the devices exhibit two types of wave modes: Rayleigh and Sezawa waves. Compared with Sezawa wave, the Rayleigh wave has a large signal amplitude up to 25 dB. In addition, as the wavelength increases, the resonant frequencies of both the Rayleigh and Sezawa waves increase whereas their phase velocities decrease. The transparent SAW devices have also demonstrated their ability to induce a strong acoustic streaming in a water droplet with a streaming velocity up to 2.27 cm/s. This research opens a door for further exploration of the SAW devices in transparent electronics. [ABSTRACT FROM AUTHOR]

Cynomolgus macaques ( Macaca fascicularis, Mafa) have emerged as an important animal model for infectious disease and transplantation research. Extensive characterization of their major histocompatibility complex (MHC) polymorphism regions therefore becomes urgently required. In this study, we identified 41 MHC class I A nucleotide sequences in 34 unrelated cynomolgus macaques of Vietnamese origin farmed in Southern China, including eight novel Mafa-A sequences. We found two sequences with perfect identity and six sequences with close similarity to previously defined MHC class I alleles from other populations, especially from Indonesian-origin macaques. We also found three Vietnamese-origin cynomolgus macaque MHC class I sequences for which the predicted protein sequences identical throughout their B and F binding pockets to Mamu- A1*001:01 and Mamu- A3*13:03, respectively. This is important because Mamu- A1*001:01 and Mamu- A3*13:03 are associated with longer survival and lower set-point viral load in simian immunodeficiency virus ( SIV)-infected rhesus monkeys. These findings have implications for the evolutionary history of Vietnamese-origin cynomolgus macaque as well as for the use of this model in SIV/ SHIV (a virus combining parts of the HIV and SIV genomes) research. [ABSTRACT FROM AUTHOR]

Abstract: We have grown high quality epitaxial topological insulator Bi2Te3 thin films on silicon (111) substrates by pulsed laser deposition. Systematic structural characterization of the films using X-ray diffraction and transmission electron microscopy has demonstrated that a low laser pulse rate is the key to achieving epitaxial films. The films show n-type metallic behavior, consistent with Te deficiency as determined by Rutherford backscattering spectrometry measurements. The A1g longitudinal optical phonon mode of Bi2Te3 was detected by time-resolved reflectivity measurements. A 2-dimensional (2-D) weak-antilocalization effect was also observed at low temperatures, which indicates the existence of topologically protected 2-D surface states in our thin films. This growth and characterization effort paves the way to fabricate multi-layer heterostructures of topological insulators along with ferromagnetic oxides and high temperature superconductors by the same growth technique in the search for physics arising from their interfacial couplings. [Copyright &y& Elsevier]

We studied the effect of irradiation on small angle grain boundaries in mosaic structured Cu thin films. The films showed a decrease in mosaic spread via a narrowing of the full width at half maximum in XRD rocking curves and a smaller minimum yield of RBS channeling after irradiation. These data indicate the irradiation decreased the misorientation angles between mosaic blocks separated by small angle grain boundaries. Mechanisms involving interactions between grain boundary dislocations and irradiation induced defects are discussed. [ABSTRACT FROM AUTHOR]

The article presents a study which identifies 10 novel major histocompatibility complex (MHC) class II alleles in cynomolgus macaques of Vietnamese origin. Cited methods include polymerase chain reaction amplification of peripheral blood samples, reverse transcriptase polymerase chain reaction, and sequencing four different clones. Results identified alleles including 21 Mafa-DPB1, 11 Mafa-DQB1 and 34 Mafa-DRB.