2,545 research outputs found
4-(4-Oxopent-2-en-2-ylÂamino)-1,2,4-triazol-1-ium-5-thiolÂate
In the title compound, C8H12N4OS, an intraÂmolecular N—Hâ‹ŻO hydrogen bond links the imine N atom to the oxo O atom. In the crystal, molÂecules are linked by interÂmolecular N—Hâ‹ŻO and N—Hâ‹ŻS hydrogen bonds, forming a two-dimensional framework
Cloning and functional analysis in transgenic tobacco of a tapetum-specific promoter from Arabidopsis
The 5’-flanking region of 1174 bp upstream of the translation start point (TSP) of a reported Arabidopsis anther-specific gene, Anther7 gene (ATA7), which putatively encodes a protein related to lipid transfer protein, was cloned and functionally analyzed in transgenic tobacco after been fused with β- glucuronidase (GUS) gene reporter. Histochemical GUS staining of the transgenic plants showed that the cloned fragment did drive GUS expression exclusively in the anther, not in any other parts of floral organs, including pollens and nor in any vegetative tissue. Transverse section of the GUS-blue anthers disclosed that the blue cells were present uniquely in the tapetum of the anther. A series of 5’-deletion of cloned fragment indicated that a short segment of 179 bp upstream of the TSP (-155 bp upstream of the transcription start site) retained not only the promoter’s driving power, but also its tapetum-specificity. Cis-acting element search in this short segment revealed the presence of numbers of organ- and tissuespecific motifs, including pollen-specific LAT52 and SLG13. These results indicated that the tapetumspecificity of ATA7 gene is mainly conferred by its promoter, and such a promoter, in particular, the core one should be useful both for identification of tapetum-involved genes and for biotechnological applications.Key words: Arabidopsis, Anther7 gene of Arabidopsis theliana (ATA7), anther-specific promoter, tapetumspecific promoter
Revealing the pulse-induced electroplasticity by decoupling electron wind force
Micro/nano electromechanical systems and nanodevices often suffer from degradation under electrical pulse. However, the origin of pulse-induced degradation remains an open question. Herein, we investigate the defect dynamics in Au nanocrystals under pulse conditions. By decoupling the electron wind force via a properly-designed in situ TEM electropulsing experiment, we reveal a non-directional migration of ÎŁ3{112} incoherent twin boundary upon electropulsing, in contrast to the expected directional migration under electron wind force. Quantitative analyses demonstrate that such exceptional incoherent twin boundary migration is governed by the electron-dislocation interaction that enhances the atom vibration at dislocation cores, rather than driven by the electron wind force in classic model. Our observations provide valuable insights into the origin of electroplasticity in metallic materials at the atomic level, which are of scientific and technological significances to understanding the electromigration and resultant electrical damage/failure inmicro/ nano-electronic devices
Unique opportunity to harness polarization in GaN to override the conventional power electronics figure-of-merits
Owing to the large breakdown electric field, wide bandgap semiconductors such
as SiC, GaN, Ga2O3 and diamond based power devices are the focus for next
generation power switching applications. The unipolar trade-off relationship
between the area specific-on resistance and breakdown voltage is often employed
to compare the performance limitation among various materials. The GaN material
system has a unique advantage due to its prominent spontaneous and
piezoelectric polarization effects in GaN, AlN, InN, AlxInyGaN alloys and
flexibility in inserting appropriate heterojunctions thus dramatically broaden
the device design space.Comment: Invited paper, to appear in IEEE Device Research Conference (DRC),
June 201
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