Rapid Communication: Genetic Linkage and Physical Mapping of the Porcine Androgen Receptor (AR) Gene

Source and Description of Primers. Primers were designed from published bovine and human androgen receptor (AR) sequences (GenBank accession number Z75315 and M27430, respectively). These primers were used to obtain a porcine sequence (submitted to GenBank: accession number AF079783). A total of 247 bp out of the entire 793-bp PCR product shared 90.3% identity with sections of exons 7 and 8 of the human AR gene. Porcine specific primers (AR-3 and AR-4) were then designed to amplify a 160-bp fragment in intron 7 of the AR gene region from porcine genomic DNA

Addition of Thirteen Genes to the Porcine Comparative Gene Map Reveals New Regions of Conserved Synteny

Thirteen genes were mapped to the porcine genome by using either linkage mapping of the PiGMaP families (eight genes) or typing of a porcine somatic cell hybrid panel (12 genes). The genes were chosen from interesting locations in the human genome. The physical gene assignments to pig chromosomes (SSC) with corresponding human chromosome (HSA) locations include the following: FGF7 (HSA15), MADH4 (HSA18), and MC4R (HSA18) to SSC1, RXRB (HSA6), and SSTR1 (HSA14) to SSC7, UCP1 (HSA4) to SSC8, PGR (HSA11) to SSC9, TTN (HSA2) and ANT1 (HSA4) to SSC15, GRIA1 (HSA5) to SSC16, AR (HSA-X), and GRIA3 (HSA-X) to SSC-X. Additionally, CD59 (HSA11) was linkage mapped to SSC2. The majority of the assignments confirm results from bidirectional chromosome painting (4). A rearrangement in gene order was detected within the region of correspondence between SSC1 and HSA15. Two assignments were made that were not expected from the painting results (MC4R and GRIA1) and one assignment of a gene from a region where the painting study was not informative (ANT1)

High-Transconductance Graphene Solution-Gated Field Effect Transistors

In this work, we report on the electronic properties of solution-gated field effect transistors (SGFETs) fabricated using large-area graphene. Devices prepared both with epitaxially grown graphene on SiC as well as with chemical vapor deposition grown graphene on Cu exhibit high transconductances, which are a consequence of the high mobility of charge carriers in graphene and the large capacitance at the graphene/water interface. The performance of graphene SGFETs, in terms of gate sensitivity, is compared to other SGFET technologies and found to be clearly superior, confirming the potential of graphene SGFETs for sensing applications in electrolytic environments.Comment: The following article has been submitted to Applied Physics Letters. After it is published, it will be found at apl.aip.or

G′ band in double- and triple-walled carbon nanotubes: A Raman study

Double- and triple-walled carbon nanotubes are studied in detail by laser energy-dependent Raman spectroscopy in order to get a deeper understanding about the second-order G[superscript '] band Raman process, general nanotube properties, such as electronic and vibrational properties, and the growth method itself. In this work, the inner nanotubes from the double- and triple-walled carbon nanotubes are produced through the encapsulation of fullerene peapods with high-temperature thermal treatments. We find that the spectral features of the G[superscript '] band, such as the intensity, frequency, linewidth, and line shape are highly sensitive to the annealing temperature variations. We also discuss the triple-peak structure of the G[superscript '] band observed in an individual triple-walled carbon nanotube taken at several laser energies connecting its Raman spectra with that for the G[superscript '] band spectra obtained for bundled triple-walled carbon nanotubes.National Science Foundation (U.S.) (Grant 1004147

Single-exposure X-ray phase imaging microscopy with a grating interferometer

The advent of hard X-ray free-electron lasers enables nanoscopic X-ray imaging with sub-picosecond temporal resolution. X-ray grating interferometry offers a phase-sensitive full-field imaging technique where the phase retrieval can be carried out from a single exposure alone. Thus, the method is attractive for imaging applications at X-ray free-electron lasers where intrinsic pulse-to-pulse fluctuations pose a major challenge. In this work, the single-exposure phase imaging capabilities of grating interferometry are characterized by an implementation at the I13-1 beamline of Diamond Light Source (Oxfordshire, UK). For comparison purposes, propagation-based phase contrast imaging was also performed at the same instrument. The characterization is carried out in terms of the quantitativeness and the contrast-to-noise ratio of the phase reconstructions as well as via the achievable spatial resolution. By using a statistical image reconstruction scheme, previous limitations of grating interferometry regarding the spatial resolution can be mitigated as well as the experimental applicability of the technique

Role of grain boundaries in tailoring electronic properties of polycrystalline graphene by chemical functionalization

Altres ajuts: Priority Program 1459 Graphene (German Research Foundation (DFG))Grain boundaries, inevitably present in chemical vapor deposited graphene, are expected to have considerable impact on the development of graphene-based hybrid materials with tailored material properties.Wedemonstrate here the critical role of polycrystallinity on the chemical functionalization of graphene comparing ozone-induced oxidation with remote plasma hydrogenation.Weshow that graphene oxidation and hydrogenation occur in two consecutive stages upon increasing defect density: an initial step in which surface-bound functional groups are generated, followed by the creation of vacancies. Remarkably, we find that hydrogenation yields homogeneously distributed defects while ozone-induced defects are preferentially accumulated at the grain boundaries eventually provoking local cracking of the structure. Supported by quantum simulations, our experimental findings reveal distinct electronic transport regimes depending on the density and distribution of induced defects on the polycrystalline graphene films. Our findings highlight the key role played by grain boundaries during graphene functionalization, and at the same time provide a novel perspective to tailor the properties of polycrystalline graphene