Measurement of nonlinear frequency shift coefficient in spin-torque oscillators based on MgO tunnel junctions

The nonlinear frequency shift coefficient, which represents the strength of the transformation of amplitude fluctuations into phase fluctuations of an oscillator, is measured for MgO-based spin-torque oscillators by analyzing the current dependence of the power spectrum. We have observed that linewidth against inverse normalized power plots show linear behavior below and above the oscillation threshold as predicted by the analytical theories for spin-torque oscillators. The magnitude of the coefficient is determined from the ratio of the linear slopes. Small magnitude of the coefficient has been obtained for the device exhibiting narrow linewidth at high bias current.Comment: 4 pages, 5 figures; accepted for publication in Applied Physics Letter

ブンレツ コウボ センショクタイ ナイブ ニ ソンザイスル テロメア ハイレツ ト テロメア ケツゴウ タンパクシツ Taz1 ニヨル フクセイ タイミング セイギョ ノ ケンキュウ

Atsutoshi, Tazumi; Masayoshi, Fukuura; Ryuichiro, Nakato; Ami, Kishimoto; Tomokazu, Takenaka; Shiho, Ogawa; Ji-hoon, Song; Tatsuro S., Takahashi; Takuro, Nakagawa; Katsuhiko, Shirahige; Hisao, Masukata. Telomere-binding protein Taz1 controls global replication timing through its localization near late replication origins in fission yeast. Genes & development. 2012. 26(18), p.2050-2062

Amplitude-Phase Coupling in a Spin-Torque Nano-Oscillator

The spin-torque nano-oscillator in the presence of thermal fluctuation is described by the normal form of the Hopf bifurcation with an additive white noise. By the application of the reduction method, the amplitude-phase coupling factor, which has a significant effect on the power spectrum of the spin-torque nano-oscillator, is calculated from the Landau-Lifshitz-Gilbert-Slonczewski equation with the nonlinear Gilbert damping. The amplitude-phase coupling factor exhibits a large variation depending on in-plane anisotropy under the practical external fields.Comment: 4 pages, 4 figures, submitted to Journal of Applied Physics via MMM 200

Identification and characterization of intervening sequences within 23S rRNA genes from more than 200 Campylobacter isolates from seven species including atypical campylobacters

<p>Abstract</p> <p>Background</p> <p>Identification and characterization of intervening sequences (IVSs) within 23S rRNA genes from <it>Campylobacter </it>organisms including atypical campylobacters were carried out using two PCR primer pairs, designed to generate helix 25 and 45 regions.</p> <p>Results</p> <p>Only <it>C. sputorum </it>biovar sputorum LMG7975 and fecalis LMG8531, LMG8534 and LMG6728 of a total of 204 <it>Campylobacter </it>isolates (n = 56 <it>C. jejuni</it>; n = 11 <it>C. coli</it>; n = 33 <it>C. fetus</it>; n = 43 <it>C. upsaliensis</it>; n = 30 <it>C. hyointestinalis</it>; n = 4 <it>C. sputorum </it>biovar sputorum; n = 5 <it>C. sputorum </it>biovar fecalis; n = 5 <it>C. sputorum </it>biovar paraureolyticus; n = 10 <it>C. concisus</it>; n = 7 <it>C. curvus</it>) were shown to carry IVSs in helix 25 region. <it>C. sputorum </it>biovar fecalis LMG8531 and LMG8534, interestingly, carried two different kinds of the 23S rRNA genes with and without the IVS, respectively. Consequently, in a total of 265 isolates of 269, including 65 <it>C. lari </it>isolates examined previously, the absence of IVSs was identified in the helix 25 region. In the helix 45 region, all the <it>C. hyointestinalis</it>, <it>C. sputorum </it>and <it>C. concisus </it>isolates were shown not to carry any IVSs. However, the 30 of 56 <it>C. jejuni </it>isolates (54%), 5 of 11 <it>C. coli </it>(45%), 25 of 33 <it>C. fetus </it>(76%), 30 of 43 <it>C. upsaliensis </it>(70%) and 6 of 7 <it>C. curvus </it>(90%) were shown to carry IVSs. In <it>C. jejuni </it>and <it>C. upsaliensis </it>isolates, two different kinds of the 23S rRNA genes were also identified to occur with and without IVSs in the helix 45 region, respectively.</p> <p>Conclusions</p> <p>Secondary structure models were also constructed with all the IVSs identified in the present study. In the purified RNA fractions from the isolates which carried the 16S or 23S rRNA genes with the IVSs, no 16S or 23S rRNA was evident, respectively.</p

Homogeneity of the 16S rDNA sequence among geographically disparate isolates of Taylorella equigenitalis

BACKGROUND: At present, six accessible sequences of 16S rDNA from Taylorella equigenitalis (T. equigenitalis) are available, whose sequence differences occur at a few nucleotide positions. Thus it is important to determine these sequences from additional strains in other countries, if possible, in order to clarify any anomalies regarding 16S rDNA sequence heterogeneity. Here, we clone and sequence the approximate full-length 16S rDNA from additional strains of T. equigenitalis isolated in Japan, Australia and France and compare these sequences to the existing published sequences. RESULTS: Clarification of any anomalies regarding 16S rDNA sequence heterogeneity of T. equigenitalis was carried out. When cloning, sequencing and comparison of the approximate full-length 16S rDNA from 17 strains of T. equigenitalis isolated in Japan, Australia and France, nucleotide sequence differences were demonstrated at the six loci in the 1,469 nucleotide sequence. Moreover, 12 polymorphic sites occurred among 23 sequences of the 16S rDNA, including the six reference sequences. CONCLUSION: High sequence similarity (99.5% or more) was observed throughout, except from nucleotide positions 138 to 501 where substitutions and deletions were noted

Molecular characterization of the sequences of the 16S-23S rDNA internal spacer region (ISR) from isolates of Taylorella asinigenitalis

<p>Abstract</p> <p>Background</p> <p>Sequence information on the 16S-23S rDNA internal spacer region (ISR) exhibits a large degree of sequence and length variation at both the genus and species levels. A primer pair for the amplification of 16S-23S rDNA ISR generated three amplicons for each of isolates of <it>Taylorella asinigenitalis </it>(UCD-1^T, UK-1 and UK-2).</p> <p>Findings</p> <p>Following TA cloning and sequencing, the three isolates of <it>T. asinigenitalis </it>were demonstrated to possess three ISR units of different lengths. Although the three corresponding ISRs (A, B and C) were identified to be identical to each other (UK-1 and UK-2 isolates), the ISRs shared approximately 95.3–98.9% nucleotide sequence similarities between the UCD-1^Tand UK-1/-2 isolates. A typical order of two intercistronic tRNA genes (5'-tRNA^Ile-tRNA^Ala-3') with the different nucleotide spacers [44 through 51 base pairs (bp)] in length was identified among the isolates. The consensus sequences of the antiterminators of <b>boxB </b>and <b>boxA </b>were also identified in all ISRs. Thus, three ISRs were identified for each isolate, and therefore, at least three distinctly different ribosomal RNA operons were suggested to occur in the genome of <it>T. asinigenitalis</it>. This was also confirmed by Southern hybridization procedure.</p> <p>Conclusion</p> <p>The present study represents a dendrogram constructed based on the nucleotide sequence data of 16S-23S rDNA ISR for <it>T. asinigenitalis</it>, which may aid in the phylogenetic positioning of <it>T. asinigenitalis </it>within the genus <it>Taylorella</it>, and in the molecular discrimination of <it>T. asinigenitalis</it>.</p

Temporal and Spatial Contiguity Are Necessary for Competition Between Events

Over the last 50 years, cue competition phenomena have shaped theoretical developments in animal and human learning. However, recent failures to observe competition effects in standard conditioning procedures, as well as the lengthy and ongoing debate surrounding cue competition in the spatial learning literature, have cast doubts on the generality of these phenomena. In the present study, we manipulated temporal contiguity between simultaneously trained predictors and outcomes (Experiments 1–4), and spatial contiguity between landmarks and goals in spatial learning (Supplemental Experiments 1 and 2; Experiment 5). Across different parametric variations, we observed overshadowing when temporal and spatial contiguity were strong, but no overshadowing when contiguity was weak. Thus, across temporal and spatial domains, we observed that contiguity is necessary for competition to occur, and that competition between cues presented simultaneously during learning is absent when these cues were either spatially or temporally discontiguous from the outcome. Consequently, we advance a model in which the contiguity between events is accounted for and which explains these results and reconciles the previously contradictory findings observed in spatial learning

構成的グループ・エンカウンター実施時における参加者の心理的変化の測定について-生理指標による測定の試み-(人間学部,聖泉大学)

本研究は,構成的グループ・エンカウンター実施時の参加者の心理的変化を,生理指標により測定することを試みた。研修参加者のうち15名(男子8名,女子7名)を対象に,各セッション後の気分を質問紙により測定するとともに,血圧計を用いて血圧と心拍数を測定した。各対象者について,気分の評定値と血圧,心拍数の対応関係を調べたが,一貫した関係性は認められなかった。しかし,比較的対応度の高い対象者と低い対象者について,対応関係や気分の変動を検討したところ,高い対象者は気分に変動がみられ,セッションを概ねポジティブに感じていること,低い対象者は気分の変動に乏しく防衛的になっている可能性があることなどが示唆された