偶発的な開花復帰性をもつ非開花性キャベツ変異体の開花制御機構に関する研究

京都大学新制・課程博士博士(農学)甲第24653号農博第2536号新制||農||1097(附属図書館)学位論文||R5||N5434(農学部図書室)京都大学大学院農学研究科農学専攻(主査)教授 土井 元章, 教授 田尾 龍太郎, 教授 那須田 周平学位規則第4条第1項該当Doctor of Agricultural ScienceKyoto UniversityDGA

Development of an efficient bioreactor system for delivering foreign proteins secreted from liver into eggs with a vitellogenin signal in medaka Oryzias latipes

In this study, we developed a novel bioreactor system to deliver and accumulate foreign proteins in eggs using medaka fish Oryzias latipes with the aid of a partial sequence of vitellogenin (Vtg). In teleost fish, Vtg, the hepatically generated precursor of egg yolk proteins, is secreted into the bloodstream and then taken up into eggs. We predicted in silico a probable region (Vtg signal) of Vtg that mediates transportation of proteins from the liver into eggs. Then, we established two transgenic lines expressing the fused proteins including the Vtg signal and each reporter gene, enhanced green fluorescent protein (EGFP) or firefly luciferase (LUC)-fused EGFP, in the liver driven by a liver-specific choriogeninH (chgH) promoter. Each reporter signal was detected from the fertilized eggs spawned by the transgenic females, showing successful transportation of the proteins into the eggs with the Vtg signal. This is the first report demonstrating that the Vtg signal has capability to deliver exogenous proteins into eggs. Because Vtg is a highly conserved protein among most of oviparous organisms, our findings hold promise for establishing bioreactor systems viable in a wide range of organisms

Frequency‐Dependent Moment Tensors of Induced Microearthquakes

Analysis of 984 induced microearthquakes from The Geysers geothermal reservoir in California reveals that the retrieved moment tensors depend on the frequency band of the inverted waveforms. The observed dependence is more significant for the percentages of the double‐couple, compensated linear vector dipole, and isotropic (ISO) components than for the focal mechanisms. The average root‐mean‐square of the moment tensors obtained in different frequency bands is correlated with spectra of ambient noise. The percentages of double‐couple and ISO components tend to decrease and increase with the upper cutoff frequency (fu), respectively. This suggests that shear rupture radiates energy preferentially in a lower frequency band and tensile rupture in a higher frequency band. Events displaying a strong increase of the ISO with fu are confined within the same depth interval as the injection points. This might be related to the strong thermoelastic effects in the vicinity of injection points that promote opening of small cracks adjacent to the main fractures

Letter identity and visual similarity in the processing of diacritic letters

Are letters with a diacritic (e.g., a) recognized as a variant of the base letter (e.g., a), or as a separate letter identity? Two recent masked priming studies, one in French and one in Spanish, investigated this question, concluding that this depends on the language-specific linguistic function served by the diacritic. Experiment 1 tested this linguistic function hypothesis using Japanese kana, in which diacritics signal consonant voicing, and like French and unlike Spanish, provide lexical contrast. Contrary to the hypothesis, Japanese kana yielded the pattern of diacritic priming like Spanish. Specifically, for a target kana with a diacritic (e.g., (sic), /ga/), the kana prime without the diacritic (e.g., (sic), /ka/) facilitated recognition almost as much as the identity prime (e.g., (sic) = (sic)), whereas for a target kana without a diacritic, the kana prime with the diacritic produced less facilitation than the identity prime (e.g., (sic) < (sic)). We suggest that the pattern of diacritic priming has little to do with linguistic function, and instead it stems from a general property of visual object recognition. Experiment 2 tested this hypothesis using visually similar letters of the Latin alphabet that differ in the presence/absence of a visual feature (e.g., O and Q). The same asymmetry in priming was observed. These findings are consistent with the noisy channel model of letter/word recognition (Norris & Kinoshita, Psychological Review, 119, 517-545, 2012a)

Attenuation performance of geosynthetic sorption sheets against arsenic subjected to compressive stresses

The attenuation layer method has been considered an effective countermeasure to deal with excavated soils and rocks containing geogenic toxic elements like arsenic (As). The geosynthetic sorption sheet is a geosynthetic product that can be employed in the attenuation layer method applications as a sorption material. The sorption sheets used in the attenuation layer will be inevitably subjected to overburdened loads in the field. In this study, laboratory column experiments are conducted to evaluate the attenuation performance of the geosynthetic sorption sheets coated with hydrotalcite as sorbent against As under different overburden pressure conditions (10, 100, and 200 kPa). Experimental results showed that the cumulative sorption masses of As for 200 kPa cases are approximately 10.5–13.3 times greater than that for 10 kPa cases. Microstructure characterizations of the geosynthetic sorption sheet before and after loading were also detected. More compacted and involved fiber configuration as a result of higher loading produces a more effective contact between As solution and hydrotalcite. The presence of partial dissolution of hydrotalcite is confirmed through the chemical analysis of effluent. However, hydrotalcite would gradually become stable during continuous use

Asteroid lightcurves from the Palomar Transient Factory survey: Rotation periods and phase functions from sparse photometry

We fit 54,296 sparsely-sampled asteroid lightcurves in the Palomar Transient Factory to a combined rotation plus phase-function model. Each lightcurve consists of 20+ observations acquired in a single opposition. Using 805 asteroids in our sample that have reference periods in the literature, we find the reliability of our fitted periods is a complicated function of the period, amplitude, apparent magnitude and other attributes. Using the 805-asteroid ground-truth sample, we train an automated classifier to estimate (along with manual inspection) the validity of the remaining 53,000 fitted periods. By this method we find 9,033 of our lightcurves (of 8,300 unique asteroids) have reliable periods. Subsequent consideration of asteroids with multiple lightcurve fits indicate 4% contamination in these reliable periods. For 3,902 lightcurves with sufficient phase-angle coverage and either a reliably-fit period or low amplitude, we examine the distribution of several phase-function parameters, none of which are bimodal though all correlate with the bond albedo and with visible-band colors. Comparing the theoretical maximal spin rate of a fluid body with our amplitude versus spin-rate distribution suggests that, if held together only by self-gravity, most asteroids are in general less dense than 2 g/cm$^3$, while C types have a lower limit of between 1 and 2 g/cm$^3$, in agreement with previous density estimates. For 5-20km diameters, S types rotate faster and have lower amplitudes than C types. If both populations share the same angular momentum, this may indicate the two types' differing ability to deform under rotational stress. Lastly, we compare our absolute magnitudes and apparent-magnitude residuals to those of the Minor Planet Center's nominal $G=0.15$, rotation-neglecting model; our phase-function plus Fourier-series fitting reduces asteroid photometric RMS scatter by a factor of 3.Comment: 35 pages, 29 figures. Accepted 15-Apr-2015 to The Astronomical Journal (AJ). Supplementary material including ASCII data tables will be available through the publishing journal's websit

The Photometric System of Tsinghua-NAOC 80-cm Telescope at NAOC Xinglong Observatory

Tsinghua-NAOC (National Astronomical Observatories of China) Telescope (hereafter, TNT) is an 80-cm Cassegrain reflecting telescope located at Xinglong bservatory of NAOC, with main scientific goals of monitoring various transients in the universe such as supernovae, gamma-ray bursts, novae, variable stars, and active galactic nuclei. We present in this paper a systematic test and analysis of the photometric performance of this telescope. Based on the calibration observations on twelve photometric nights, spanning the period from year 2004 to year 2012, we derived an accurate transformation relationship between the instrumental $ubvri$ magnitudes and standard Johnson $UBV$ and Cousins $RI$ magnitudes. In particular, the color terms and the extinction coefficients of different passbands are well determined. With these data, we also obtained the limiting magnitudes and the photometric precision of TNT. It is worthwhile to point out that the sky background at Xinglong Observatory may become gradually worse over the period from year 2005 to year 2012 (e.g., $\sim$21.4 mag vs. $\sim$20.1 mag in the V band).Comment: 12 pages,9 figures, accepted by RA

Compton and double Compton scattering processes at colliding electron-photon beams

Radiative corrections (RC) to the Compton scattering cross section are calculated in the leading and next-to leading logarithmic approximation to the case of colliding high energy photon-electron beams. RC to the double Compton scattering cross section in the same experimental set-up are calculated in the leading logarithmic approximation. We consider the case when no pairs are created in the final state. We show that the differential cross section can be written in the form of the Drell-Yan process cross-section. Numerical values of the $K$-factor and the leading order distribution on the scattered electron energy fraction and scattering angle are presented

STAT1/3 signaling suppresses axon degeneration and neuronal cell death through regulation of NAD+-biosynthetic and consuming enzymes

Nicotinamide adenine dinucleotide (NAD)+-biosynthetic and consuming enzymes are involved in various intracellular events through the regulation of NAD+ metabolism. Recently, it has become clear that alterations in the expression of NAD+-biosynthetic and consuming enzymes contribute to the axonal stability of neurons. We explored soluble bioactive factor(s) that alter the expression of NAD+-metabolizing enzymes and found that cytokine interferon (IFN)-γ increased the expression of nicotinamide nucleotide adenylyltransferase 2 (NMNAT2), an NAD+-biosynthetic enzyme. IFN-γ activated signal transducers and activators of transcription 1 and 3 (STAT1/3) followed by c-Jun N-terminal kinase (JNK) suppression. As a result, STAT1/3 increased the expression of NMNAT2 at both mRNA and protein levels in a dose- and time-dependent manner and, at the same time, suppressed activation of sterile alpha and Toll/interleukin receptor motif-containing 1 (SARM1), an NAD+-consuming enzyme, and increased intracellular NAD+ levels. We examined the protective effect of STAT1/3 signaling against vincristine-mediated cell injury as a model of chemotherapy-induced peripheral neuropathy (CIPN), in which axonal degeneration is involved in disease progression. We found that IFN-γ-mediated STAT1/3 activation inhibited vincristine-induced downregulation of NMNAT2 and upregulation of SARM1 phosphorylation, resulting in modest suppression of subsequent neurite degradation and cell death. These results indicate that STAT1/3 signaling induces NMNAT2 expression while simultaneously suppressing SARM1 phosphorylation, and that both these actions contribute to suppression of axonal degeneration and cell death