302 research outputs found

    Multipole ordering in f-electron systems

    Full text link
    In order to investigate multipole ordering in f-electron systems from a microscopic viewpoint, we study the so-called \Gamma_8 models on three kinds of lattices, simple cubic (sc), bcc, and fcc, based on a j-j coupling scheme with f-electron hopping integrals through (ff\sigma) bonding. From the \Gamma_8 model, we derive an effective model for each lattice structure by using the second-order perturbation theory with respect to (ff\sigma). By further applying mean-field theory to the effective model, we find a \Gamma_{3g} antiferro-quadrupole transition for the sc lattice, a \Gamma_{2u} antiferro-octupole transition for the bcc lattice, and a longitudinal triple-q \Gamma_{5u} octupole transition for the fcc lattice.Comment: 2 pages, 3 figure

    <臨床>胃癌術後に肺転移巣を切除した2例

    Get PDF
    It is said that the prognosis is poor in cases with recurrent pulmonary metastasis after operation for gastric cancer. In this article, 2 cases with nodular type of pulmonary metastasis resected after operation for gastric cancer and surviving well are reported by the authors. Case 1: 57year-old female. The patient underwent a total gastrectomy for the 3'type of cardiac cancer. As the serum levels of tumor markers increased and the chest X-ray examination revealed a mass lesion in the right lung (S_10), the operation for the lesion under the diagnosis of metastatic lung cancer was performed 1 year and 2 months after gastrectomy. The patient died of pulmonal and pleural metastasis 4 years and 7 months after the first operation. Case 2: 65-year-old male. The patient underwent a subtotal gastrectomy for the 5'type of gastric cancer. Chest X-ray examination for follow-up study revealed a mass lesion in the left lung (S_5). The patient underwent a left pulmonary superior lobe resection 2 years and 9 months after gastrectomy. The patient is still alive 6 years after the first operation. Surgical treatment must be actively considered for nodular type of metastatic lung cancer after operation for gastric cancer.胃癌術後に肺転移をきたした症例の予後は不良とされている. 今回, 胃切除術後に結節型肺転移巣を切除し, 良好な結果を得た胃癌の2例を経験したので、報告する. 症例 1 は57歳, 女性. 噴門部 2'型胃癌の診断のもと, 胃全摘術を受けている. 腫瘍マーカーの上昇があり, 胸部X線写真で右肺 S_10 に腫瘤陰影を認めた. 胃癌術後1年2カ月目に肺部分切除術を施行した. 患者は胃癌切除後4年7カ月で肺転移および癌性胸膜炎のため死亡した. 症例2は65歳, 男性. 胃体部 5'型胃癌の診断のもと, 胃亜全摘を受けている. 術後経過観察中, 胸部X線写真で左肺 S_5 に腫瘤陰影を認め, 胃癌術後2年9カ月目に左肺上葉切除切除術を施行した. 患者は胃癌切除術後6年で健在である. 結節型の肺転移例に対しては積極的な外科手術を考慮すべきである

    Self-Reduction Rate of a Microtubule

    Full text link
    We formulate and study a quantum field theory of a microtubule, a basic element of living cells. Following the quantum theory of consciousness by Hameroff and Penrose, we let the system to reduce to one of the classical states without measurement if certain conditions are satisfied(self-reductions), and calculate the self-reduction time τN\tau_N (the mean interval between two successive self-reductions) of a cluster consisting of more than NN neighboring tubulins (basic units composing a microtubule). τN\tau_N is interpreted there as an instance of the stream of consciousness. We analyze the dependence of τN\tau_N upon NN and the initial conditions, etc. For relatively large electron hopping amplitude, τN\tau_N obeys a power law τNNb\tau_N \sim N^b, which can be explained by the percolation theory. For sufficiently small values of the electron hopping amplitude, τN\tau_N obeys an exponential law, τNexp(cN)\tau_N \sim \exp(c' N). By using this law, we estimate the condition for τN\tau_N to take realistic values τN\tau_N \raisebox{-0.5ex}{>\stackrel{>}{\sim}} 10110^{-1} sec as NN \raisebox{-0.5ex} {>\stackrel{>}{\sim}} 1000.Comment: 7 pages, 9 figures, Extended versio

    Molecular architecture of inner dynein arms in situ in Chlamydomonas reinhardtii flagella

    Get PDF
    The inner dynein arm regulates axonemal bending motion in eukaryotes. We used cryo-electron tomography to reconstruct the three-dimensional structure of inner dynein arms from Chlamydomonas reinhardtii. All the eight different heavy chains were identified in one 96-nm periodic repeat, as expected from previous biochemical studies. Based on mutants, we identified the positions of the AAA rings and the N-terminal tails of all the eight heavy chains. The dynein f dimer is located close to the surface of the A-microtubule, whereas the other six heavy chain rings are roughly colinear at a larger distance to form three dyads. Each dyad consists of two heavy chains and has a corresponding radial spoke or a similar feature. In each of the six heavy chains (dynein a, b, c, d, e, and g), the N-terminal tail extends from the distal side of the ring. To interact with the B-microtubule through stalks, the inner-arm dyneins must have either different handedness or, more probably, the opposite orientation of the AAA rings compared with the outer-arm dyneins

    Fertilization Recovery after Defective Sperm Cell Release in Arabidopsis

    Get PDF
    SummaryIn animal fertilization, multiple sperms typically arrive at an egg cell to “win the race” for fertilization. However, in flowering plants, only one of many pollen tubes, conveying plant sperm cells, usually arrives at each ovule that harbors an egg cell [1, 2]. Plant fertilization has thus been thought to depend on the fertility of a single pollen tube [1]. Here we report a fertilization recovery phenomenon in flowering plants that actively rescues the failure of fertilization of the first mutant pollen tube by attracting a second, functional pollen tube. Wild-type (WT) ovules of Arabidopsis thaliana frequently (∼80%) accepted two pollen tubes when entered by mutant pollen defective in gamete fertility. In typical flowering plants, two synergid cells on the side of the egg cell attract pollen tubes [3–5], one of which degenerates upon pollen tube discharge [3, 6]. By semi-in vitro live-cell imaging [7, 8] we observed that fertilization was rescued when the second synergid cell accepted a WT pollen tube. Our results suggest that flowering plants precisely control the number of pollen tubes that arrive at each ovule and employ a fertilization recovery mechanism to maximize the likelihood of successful seed set

    Prediction of acute left main coronary artery obstruction by 12-lead electrocardiography ST segment elevation in lead aVR with less ST segment elevation in lead V1

    Get PDF
    AbstractOBJECTIVESWe sought to determine the electrocardiographic (ECG) features associated with acute left main coronary artery (LMCA) obstruction.BACKGROUNDPrediction of LMCA obstruction is important with regard to selecting the appropriate treatment strategy, because acute LMCA obstruction usually causes severe hemodynamic deterioration, resulting in a less favorable prognosis.METHODSWe studied the admission 12-lead ECGs in 16 consecutive patients with acute LMCA obstruction (LMCA group), 46 patients with acute left anterior descending coronary artery (LAD) obstruction (LAD group) and 24 patients with acute right coronary artery (RCA) obstruction (RCA group).RESULTSLead aVR ST segment elevation (>0.05 mV) occurred with a significantly higher incidence in the LMCA group (88% [14/16]) than in the LAD (43% [20/46]) or RCA (8% [2/24]) groups. Lead aVR ST segment elevation was significantly higher in the LMCA group (0.16 ± 0.13 mV) than in the LAD group (0.04 ± 0.10 mV). Lead V1ST segment elevation was lower in the LMCA group (0.00 ± 0.21 mV) than in the LAD group (0.14 ± 0.11 mV). The finding of lead aVR ST segment elevation greater than or equal to lead V1ST segment elevation distinguished the LMCA group from the LAD group, with 81% sensitivity, 80% specificity and 81% accuracy. A ST segment shift in lead aVR and the inferior leads distinguished the LMCA group from the RCA group. In acute LMCA obstruction, death occurred more frequently in patients with higher ST segment elevation in lead aVR than in those with less severe elevation.CONCLUSIONSLead aVR ST segment elevation with less ST segment elevation in lead V1is an important predictor of acute LMCA obstruction. In acute LMCA obstruction, lead aVR ST segment elevation also contributes to predicting a patient’s clinical outcome

    ECCD Experiment Using an Upgraded ECH System on LHD

    Get PDF
    Electron cyclotron current drive (ECCD) is an attractive tool for controlling plasmas. In the large helical device (LHD), ECCD experiments have been performed by using an EC-wave power source, gyrotron, with a frequency of 84 GHz. The maximum driven current was ?9 kA with 100 kW injection power to plasma and 8 s duration of EC-wave pulse. These years, high-power and long-pulse 77 GHz gyrotrons were newly installed. An ECCD experiment with 775 kW injection power was performed. The 77 GHz waves of 8 s pulse duration sustained the plasmas. The EC-wave beam direction was scanned toroidally, keeping the beam direction aiming at the magnetic axis in X-mode polarization. In spite of the change in the EC-wave beam direction, plasma parameters such as the line-average electron density, the central electron temperature and the plasma stored energy were kept nearly the same values for the discharges, ?0.3 × 1019 m?3, ?3 keV and ?30 kJ, except for the plasma current. The plasma current showed a systematic change with the change in the beam direction for ECCD, and at an optimum direction with N// ? ?0.3, the plasma current reached its maximum, ?40 kA. Also, current drive efficiency normalized with density and power was improved by 50% compared with that at the former 84 GHz ECCD experiment

    “Transmantle sign”を示す限局性皮質異形成における神経細胞の成熟と分化の未熟性:層特異的マーカー発現による解析

    Get PDF
    Transmantle dysplasia is a rare type of focal cortical dysplasia (FCD) characterized by expansion of the cortex from the deep white matter to the surface and in which there is a FCD IIA or IIB pathologic pattern. To characterize possible mechanisms underlying this regional disorder of radial migrating cells, we studied the expression patterns of neocortical layer-specific markers using immunohistochemistry in surgical specimens from 5 FCD IIA and 4 FCD IIB cases in children. All neuronal cells expressed the mature neuron marker MAP2/2B but not the microglia markers Iba-1 and CD68. Some layer-specific markers showed distinct expression patterns. TBR1-positive, SATB2-positive, and FOXP1-positive cells were diffusely distributed in the cortex and/or the white matter. TBR1-positive and FOXP1-positive cells were generally more numerous in FCD IIB than in FCD IIA and were mostly in the cortical molecular and upper layers. FOXP1-, FOXP2-, and CUTL1-positive cells also expressed the immature neuron marker, Nestin/PROX1, whereas TBR1-, CTIP2-, and SATB2-positive cells only expressed MAP2/2B. These data highlight differences between FCD IIB and FCD IIA with more cells having the immature marker in upper layer markers in the former. By analyzing layer-specific marker expression patterns, we identified apparent neuronal maturation differences between FCD IIA and FCD IIB in cases of transmantle dysplasia.博士(医学)・乙第1312号・平成25年5月29
    corecore