Diagnosing Nanoelectronic Components Using Coherent Electrons

We present the direct observation, using off-axis electron holography (EH), of the electric potential distribution in the vicinity of a single carbon nanotube electrically biased by two closely spaced contacts. When our results are combined with finite element modeling, we demonstrate the ability to separately observe the electrostatic potential drops across the metal contacts at the interface with the nanotube and along the length of the nanotube itself. We demonstrate that the uneven resistivity of different contacts can cause an asymmetric EH phase shift, which can readily be identified and quantified. EH thus offers a unique and precise approach for in-depth understanding and quick diagnosis of many similar nanoscale electronic devices

Kv2.1(Y124F) mutation blocks both Src- and p38-induced phosphorylation of Kv2.1 at S800.

<p><b>A,</b> CHO cells were co-transfected with plasmid DNAs of Kv2.1 (10%) or Kv2.1(Y124F, 30%), and Src (15%) or p38 (15%). The membranes carrying with immunoprecipitated Kv2.1 protein complexes were co-probed with anti-Kv2.1 mouse monoclonal antibody and rabbit antibody specific against serine phosphorylation of Kv2.1 at S800, p-Kv2.1(S800). <b>B,</b> The signal densities of p-Kv2.1(S800) and total Kv2.1 proteins from Y124F mutants in either p38- or Src-expressing CHO cells (panels of Fig 2A) were quantified and the level of p-Kv2.1(S800) was expressed as a ratio of p-Kv2.1(S800) to total Kv2.1 protein and normalized to respective wild type controls (as 100%). The data represents mean ± SEM from 5 independent experiments for each condition (*<i>p</i> < 0.05 and **<i>p</i> < 0.01, one sample, two-tailed paired <i>t</i> test, vs. 100).</p

Taxonomic hypotheses of <i>Petaurista.</i>

a<p>Ellerman (1940) recognized 31 species, 14 of which (P. cineraceus, P. lylei, P. mergulus, P. annamensis, P. candidulus, P. taylori, P. fulvinus, P. inornatus, P. birrelli, P. gorkhali, P. melanopterus, P. sulcatus, P. rubicundus and P. filchnerinae) have not been recognized as valid Petaurista species by any other researcher.</p

N- and C-terminal cysteine residues differentially influence Kv2.1 phosphorylation.

<p><b>A,</b> CHO cells were co-transfected with plasmid DNAs of p38 (15%), and Kv2.1(WT) (10%), Kv2.1(C73A) (30%), or Kv2.1(C710A) (30%). The membranes with separated immunoprecipitated Kv2.1 protein complexes were co-probed with mouse anti-Kv2.1 monoclonal antibody and rabbit polyclonal antibody specific against serine phosphorylation of Kv2.1 at S800, p-Kv2.1(S800). The level of p-Kv2.1(S800) was calculated from the ratio of p-Kv2.1(S800) to total Kv2.1 protein, and then normalized to the level of p-Kv2.1(S800, WT) in p38-transfected CHO cells. The values represent mean ± SEM from 7 independent experiments (****<i>p</i> < 0.0001, compared with Kv2.1WT; one sample, two-tailed <i>t</i> test; and ^ΔΔΔ<i>p</i> < 0.001, two-tailed paired <i>t</i> test). <b>B,</b> CHO cells were co-transfected with plasmid DNAs of Src (15%), and Kv2.1 (WT, 10%), Kv2.1(C73A, 30%), or Kv2.1(C710A, 30%). Immunoblot was co-probed with rabbit anti-Kv2.1 polyclonal antibody (Kv2.1) and mouse anti-phosphotyrosine antibody, p-Kv2.1(Tyr). The signal densities of p-Kv2.1(Tyr) and total Kv2.1 proteins from Kv2.1WT, Kv2.1(C73A) and Kv2.1(C710A) were quantified as described above. The level of p-Kv2.1(Tyr) was calculated as the ratio of pKv2.1(Tyr) to total Kv2.1 protein and normalized to tyrosine phosphorylation of Kv2.1WT in CHO cells with Src overexpression. Similar p-Kv2.1(Tyr) levels were detected in Src-expressing CHO cells in WT, C73A and C710A groups.</p

Genetic differences of <i>Petaurista</i> taxa based on pairwise comparisons of complete cytochrome <i>b</i> gene sequences (1,140 bp).

<p>Data above the diagonal represent the transversional percentage differences of the 3rd codon position of sequences among taxa. Data below the diagonal are the percentage differences of sequences among taxa.</p

Phylogenies of <i>Petaurista</i> species based on cyt <i>b</i> (Oshida et al., 2000a, 2000b, 2004; Yu et al., 2006).

<p>Phylogenies of <i>Petaurista</i> species based on cyt <i>b</i> (Oshida et al., 2000a, 2000b, 2004; Yu et al., 2006).</p

Phylogenetic relationships of <i>Petaurista</i> constructed based on 1,068–1,140 bp of the cyt <i>b</i> gene using the ML method and BI.

<p>Numbers above the branches are Bayesian posterior probabilities/likelihood bootstrap values.</p

Src expression increases p38-dependent phosphorylation of Kv2.1 at S800.

<p><b>A,</b> CHO cells were co-transfected with plasmid DNAs of Kv2.1 (10% of total DNA, see <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0129498#sec002" target="_blank">Methods</a>), and either Src (15%) or p38 (15%). The membranes with immunoprecipitated Kv2.1 protein were co-probed with anti-Kv2.1 mouse monoclonal antibody and rabbit antibody specific against phosphorylation of Kv2.1 at residue S800. The levels of pKv2.1(S800) in Src- and p38-expressing CHO cells are expressed as the ratio of pKv2.1(S800) to total Kv2.1 protein, and normalized to the same ratio obtained from control cells (value of 1). The data represent mean ± SEM from 6–7 independent experiments (**<i>p</i> < 0.01, two-tailed, unpaired <i>t</i> test). <b>B,</b> Protein samples were harvested from Src- or control vector DNA-expressing CHO cells, the levels of total p38 protein (p38) and phosphorylated p38 protein (p-p38) in equal amounts of total cell lysates were detected by western blotting by using mouse antibody specific against p-p38 and rabbit antibody against total p38 protein. Results (mean ± SEM from 5 independent experiments) show that there is no change of p-p38 levels in Src-overexpressing CHO cells when compared with control cells. <b>C,</b> CHO cells were co-transfected with plasmid DNAs of Kv2.1 (10%), and either Src (15%) or control vector. Three hours later, transfected cells were treated with a specific p38 MAPK kinase inhibitor, SB 239063 (5 μM). Kv2.1 protein was immunoprecipitated and separated. Immunoblot was performed and quantified as described in Fig 1A. Values (mean ± SEM from 3 independent experiments) represent the ratios of the level of pKv2.1(S800) to total Kv2.1 normalized to their respective controls (-Src, no drug and—Src plus drug; **<i>p</i> < 0.01, two-tailed, paired <i>t</i> test). <b>D,</b> CHO cells were co-transfected with plasmid DNAs of Kv2.1 (10%) and either Src (15%), p38DN (15%) or control vector. Kv2.1 protein in transfected cells was immunoprecipitated, and quantified as described above. Values (mean ± SEM from 4 independent experiments) represent the ratio of the level of pKv2.1(S800) to total Kv2.1 normalized to respective controls, as in <b>C</b> (*<i>p</i> < 0.01, two-tailed, paired <i>t</i> test).</p

AU, KH and SH tests.

<p>Clade numbers are represented in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0070461#pone-0070461-g002" target="_blank">Figures 2</a> and <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0070461#pone-0070461-g003" target="_blank">3</a>.</p

Src-induced tyrosine phosphorylation of Kv2.1 in CHO cells is significantly decreased in Kv2.1(S800A) mutants.

<p><b>A,</b> CHO cells were co-transfected with plasmid DNAs of Kv2.1 (10%), Kv2.1(S800A) (10%), Src (15%) and vector controls. Protein samples were collected 24 h later and Kv2.1 protein was immunoprecipitated and transferred onto nitrocellulose membranes. The membranes were co-probed with mouse anti-phospho-tyrosine monoclonal antibody, p-Kv2.1(Tyr) and rabbit polyclonal antibody specific against total Kv2.1 (Kv2.1). <b>B,</b> CHO cells were co-transfected with plasmid DNAs of Kv2.1 (10%), Kv2.1(S800E) (10%), Src (15%) and vector controls, followed by experimental procedures described in Fig 3A. <b>C,</b> The signal densities of p-Kv2.1(Tyr) and total Kv2.1 proteins from Kv2.1WT, Kv2.1(S800A) and Kv2.1(S800E) were quantified as described earlier. The level of p-Kv2.1(Tyr) was expressed as a ratio of p-Kv2.1(Tyr) to total Kv2.1 protein and normalized to the tyrosine phosphorylation level of Kv2.1WT in CHO cells without Src overexpression. The data represents mean ± SEM from 4 independent experiments (***<i>p</i> < 0.001, compared with Kv2.1WT; one sample, two-tailed <i>t</i> test; and ^ΔΔ<i>p</i> < 0.01, two-tailed, paired <i>t</i> test).</p