508 research outputs found
Tuning the electrocaloric enhancement near the morphotropic phase boundary in lead-free ceramics
This project was funded by EPSRC (EP/G060940/1 and EP/P505674/1) and the Grant Agency of the Slovak
Academy of Sciences (2/0057/14)
Twinning superlattices in indium phosphide nanowires
Here, we show that we control the crystal structure of indium phosphide (InP)
nanowires by impurity dopants. We have found that zinc decreases the activation
barrier for 2D nucleation growth of zinc-blende InP and therefore promotes the
InP nanowires to crystallise in the zinc blende, instead of the commonly found
wurtzite crystal structure. More importantly, we demonstrate that we can, by
controlling the crystal structure, induce twinning superlattices with
long-range order in InP nanowires. We can tune the spacing of the superlattices
by the wire diameter and the zinc concentration and present a model based on
the cross-sectional shape of the zinc-blende InP nanowires to quantitatively
explain the formation of the periodic twinning.Comment: 18 pages, 4 figure
Endogenous polyamines reduce the toxicity of soluble Aβ peptide aggregates associated with Alzheimer’s disease
Biophysical Structural Chemistr
Functional epigenetic approach identifies frequently methylated genes in Ewing sarcoma
Using a candidate gene approach we recently identified frequent methylation of the RASSF2 gene associated with poor overall survival in Ewing sarcoma (ES). To identify effective biomarkers in ES on a genome-wide scale, we used a functionally proven epigenetic approach, in which gene expression was induced in ES cell lines by treatment with a demethylating agent followed by hybridization onto high density gene expression microarrays. After following a strict selection criterion, 34 genes were selected for expression and methylation analysis in ES cell lines and primary ES. Eight genes (CTHRC1, DNAJA4, ECHDC2, NEFH, NPTX2, PHF11, RARRES2, TSGA14) showed methylation frequencies of>20% in ES tumors (range 24-71%), these genes were expressed in human bone marrow derived mesenchymal stem cells (hBMSC) and hypermethylation was associated with transcriptional silencing. Methylation of NPTX2 or PHF11 was associated with poorer prognosis in ES. In addition, six of the above genes also showed methylation frequency of>20% (range 36-50%) in osteosarcomas. Identification of these genes may provide insights into bone cancer tumorigenesis and development of epigenetic biomarkers for prognosis and detection of these rare tumor types
Prediction of Anisotropic Single-Dirac-Cones in BiSb Thin Films
The electronic band structures of BiSb thin films can be
varied as a function of temperature, pressure, stoichiometry, film thickness
and growth orientation. We here show how different anisotropic
single-Dirac-cones can be constructed in a BiSb thin film for
different applications or research purposes. For predicting anisotropic
single-Dirac-cones, we have developed an iterative-two-dimensional-two-band
model to get a consistent inverse-effective-mass-tensor and band-gap, which can
be used in a general two-dimensional system that has a non-parabolic dispersion
relation as in a BiSb thin film system
Search for the pentaquark via the reaction at 1.92 GeV/
The pentaquark baryon was searched for via the
reaction in a missing-mass resolution of 1.4 MeV/(FWHM) at J-PARC.
meson beams were incident on the liquid hydrogen target with the beam momentum
of 1.92 GeV/. No peak structure corresponding to the mass was
observed. The upper limit of the production cross section averaged over the
scattering angle of 2 to 15 in the laboratory frame was
obtained to be 0.26 b/sr in the mass region of 1.511.55 GeV/.The
upper limit of the decay width using the effective Lagrangian
approach was obtained to be 0.72 MeV/ and 3.1 MeV/ for
and , respectively.Comment: 5 pages, 3 figures, 1 tabl
Establishment of a New Cell Line from Lepidopteran Epidermis and Hormonal Regulation on the Genes
When an insect molts, old cuticle on the outside of the integument is shed by apolysis and a new cuticle is formed under the old one. This process is completed by the epidermal cells which are controlled by 20-hydroxyecdysone (20E) and juvenile hormone. To understand the molecular mechanisms of integument remolding and hormonal regulation on the gene expression, an epidermal cell line from the 5th instar larval integument of Helicoverpa armigera was established and named HaEpi. The cell line has been cultured continuously for 82 passages beginning on June 30, 2005 until now. Cell doubling time was 64 h. The chromosomes were granular and the chromosome mode was from 70 to 76. Collagenase I was used to detach the cells from the flask bottom. Non-self pathogen AcMNPV induced the cells to apoptosis. The cell line was proved to be an epidermal cell line based on its unique gene expression pattern. It responded to 20E and the non-steroidal ecdysone agonist RH-2485. Its gene expression could be knocked down using RNA interference. Various genes in the cell line were investigated based on their response to 20E. This new cell line represents a platform for investigating the 20E signaling transduction pathway, the immune response mechanism in lepidopteran epidermis and interactions of the genes
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