Size and shape evolution of embedded single-crystal αα-Fe nanowires

The size and shape evolution of embedded ferromagnetic αα-Fe nanowires is discussed. The αα-Fe nanowires are formed by pulsed-laser deposition of La0.5Sr0.5FeO3−xLa0.5Sr0.5FeO3−x on single-crystal SrTiO3SrTiO3 (001) substrate in reducing atmosphere. The average diameter of the nanowires increases from d ≈ 4d≈4 to 50 nm as the growth temperature increases from T = 560T=560 to 840 °C. Their in-plane shape evolves from circular to octahedral and square shape with [110] facets dominating as the growth temperature increases. A fitting to a theoretical calculation shows that the circular shape is stable when the diameter of the nanowires is smaller than 8 nm.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/87835/2/203110_1.pd

Preparation of p-type ZnMgO thin films by Sb doping method

We report on Sb-doped p-type Zn0.95Mg0.05O thin films grown by pulsed laser deposition. The Sb-doped Zn0.95Mg0.05O films show an acceptable p-type conductivity with a resistivity of 126 Ω cm, a Hall mobility of 1.71 cm2 V−1 s−1 and a hole concentration of 2.90 × 1016 cm−3 at room temperature. Secondary ion mass spectroscopy confirms that Sb has been incorporated into the Zn0.95Mg0.05O films. Guided by x-ray photoemission spectroscopy analysis and a model for large-size-mismatched group-V dopants in ZnO, an SbZn–2VZn complex is believed to be the most possible acceptor in the Sb-doped p-type Zn0.95Mg0.05O thin films.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/58103/2/d7_14_020.pd

Flux pinning enhancement in ferromagnetic and superconducting thin-film multilayers

Flux pinning in high-temperature superconductors such as YBa2Cu3O7−xYBa2Cu3O7−x (YBCO) in the past has been accomplished by pinning the vortex cores. We demonstrate magnetic-domain-induced flux pinning of the magnetic flux of vortices in a ferromagnet-superconductor bilayer consisting of CoPt grown on YBCO, where the ferromagnet has uniaxial perpendicular magnetic anisotropy and a random domain structure. We observe an improvement of the critical current due to magnetic pinning at temperatures close to the transition temperature. © 2003 American Institute of Physics.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/71072/2/APPLAB-82-5-778-1.pd

miR-16 Targets Transcriptional Corepressor SMRT and Modulates NF-kappaB-Regulated Transactivation of Interleukin-8 Gene

The signaling pathways associated with the Toll-like receptors (TLRs) and nuclear factor-kappaB (NF-κB) are essential to pro-inflammatory cytokine and chemokine expression, as well as initiating innate epithelial immune responses. The TLR/NF-κB signaling pathways must be stringently controlled through an intricate network of positive and negative regulatory elements. MicroRNAs (miRNAs) are non-coding small RNAs that regulate the stability and/or translation of protein-coding mRNAs. Herein we report that miR-16 promotes NF-κB-regulated transactivation of the IL-8 gene by suppression of the silencing mediator for retinoid and thyroid hormone receptor (SMRT). LPS stimulation activated miR-16 gene transcription in human monocytes (U937) and biliary epithelial cells (H69) through MAPK-dependent mechanisms. Transfection of cells with the miR-16 precursor promoted LPS-induced production of IL-8, IL-6, and IL-1α, without a significant effect on their RNA stability. Instead, an increase in NF-κB-regulated transactivation of the IL-8 gene was confirmed in cells following transfection of miR-16 precursor. Importantly, miR-16 targeted the 3′-untranslated region of SMRT and caused translational suppression of SMRT. LPS decreased SMRT expression via upregulation of miR-16. Moreover, functional manipulation of SMRT altered NF-κB-regulated transactivation of LPS-induced IL-8 expression. These data suggest that miR-16 targets SMRT and modulates NF-κB-regulated transactivation of the IL-8 gene

Deposition and Properties of Superconducting MgB 2 Thin Films

The recently discovered superconductor MgB 2 with T c at 39 K has great potential in superconducting electronics. In this paper, we review the deposition techniques used for MgB 2 thin films in the light of a thermodynamic study of the Mg-B system with the calculation of phase diagrams (CALPHAD) modeling technique. This thermodynamic study identifies a growth window in the pressure–temperature phase diagram, in which the magnesium pressure is very high for likely in situ growth temperatures. A Hybrid Physical–Chemical Vapor Deposition (HPCVD) technique that successfully achieves such a high Mg pressure is shown to produce in situ epitaxial MgB 2 thin films with bulk superconducting properties.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/45120/1/10948_2004_Article_474022.pd

Pneumonia Incidence and Mortality in Mainland China: Systematic Review of Chinese and English Literature, 1985–2008

BACKGROUND: Pneumonia is a leading infectious disease killer worldwide, yet the burden in China is not well understood as much of the data is published in the non-English literature. METHODOLOGY/PRINCIPAL FINDINGS: We systematically reviewed the Chinese- and English-language literature for studies with primary data on pneumonia incidence and mortality in mainland China. Between 1985 and 2008, 37 studies met the inclusion criteria. The quality of the studies was highly variable. For children <5 years, incidence ranged from 0.06-0.27 episodes per person-year and mortality ranged from 184-1,223 deaths per 100,000 population. Overall incidence and mortality were stable or decreased over the study period and were higher in rural compared to urban areas. CONCLUSIONS/SIGNIFICANCE: Pneumonia continues to be a major public health challenge in young children in China, and estimates of pneumonia incidence and mortality vary widely. Reliable surveillance data and new prevention efforts may be needed to achieve and document additional declines, especially in areas with higher incidence and mortality such as rural settings