The Neurophysiological Implications of an Atypical Slow Negative Potential in Short Interval CNV Paradigm

We recorded a slow negative potential from Cz (10/20 method) in 49 healthy students (12 male, 37 female, mean age 19.1) by a short interstumulus interval CNV paradigm. The interstimulus interval was 2 or 3 seconds, the warning stimulus presented at random or regular interval at 0.2 Hz. An atypical negative variation with two separated negative peaks was recorded in 26.0-30.6% trials regardless of interstimulus interval or modality of warning stimulus presentation, while a typical CNV was recorded in 32.0-59.2% of trials. No apparent negative variation was recorded in 14.3-18.4% in 2 seconds interstimulus interval, and 28-38% in 3 seconds interstimulus interval, showing that 2 seconds interval is better to get stable CNV recording than 3 seconds interval. The first negative wave of the atypical negative variation was 692-799msec in duration, but frequently prolonged to 1000msec or more in 3 seconds interval. It usually had negative peak around 900-1100msec, but sometimes around 1500msec. This features are different from any reported negative components of CNV. The second negative wave began 800-1200msec before second stimulus, and had its peak just before second stimulus, showing common features with readiness potential. The appearance of CNV was unsatble in the students in which the atypical negative variation was recorded in regular, 2 seconds intersitimulus interval, and the amplitude of slow vertex response and pattern reversal visual evoked potential was lower in thses students than in the students in which a typical CNV was recorded more than 3 times in total 4 times of trials. These findings indicate that the atypical variation observed in this study is due to a lowered arousal level or cortical neuronal activity, rather than a separated appearance of different components of CNV.CNVの記録条件を検討する目的で、健康若年成人49名（男12、女37）を対象にS(1)-S(2)+Rパラダイムを用いてCNVを記録した。S(1)-S(2)間隔2秒のほうが3秒よりも安定してCNVが記録されたが、刺激間隔とは無関係に26～30％の試行で二峰性の陰性変動をもつ非定型な緩電位が記録された。この緩電位は同一被検者でも出現性が一貫せず、個体差よりも被検者の状態に依存していた。二峰性陰性波のうち、後期成分は準備電位に対応するものと思われたが、前期成分はS(1)後900～1100msecにピークをもつ陰性波で、これまで報告されたCNVの要素波とは対応しなかった。また、この非定型CNVを示す被検者ではCNV出現が不安定で、SVRおよびパターンVEPの振幅が低い傾向があり、試行時の被検者の覚醒水準低下よるものではないかと考えられた

Physical Relation of Source I to IRc2 in the Orion KL Region

We present mid-infrared narrow-band images of the Orion BN/KL region, and N-band low-resolution spectra of IRc2 and the nearby radio source "I." The distributions of the silicate absorption strength and the color temperature have been revealed with a sub-arcsecond resolution. The detailed structure of the 7.8 micron/12.4 micron color temperature distribution was resolved in the vicinity of IRc2. A mid-infrared counterpart to source I has been detected as a large color temperature peak. The color temperature distribution shows an increasing gradient from IRc2 toward source I, and no dominant temperature peak is seen at IRc2. The spectral energy distribution of IRc2 could be fitted by a two-temperature component model, and the "warmer component" of the infrared emission from IRc2 could be reproduced by scattering of radiation from source I. IRc2 itself is not self-luminous, but is illuminated and heated by an embedded luminous young stellar object located at source I.Comment: 20 pages, 11 figures. Minor corrections had been done in the ver.2. Accepted for publication in PAS

Inspection Method by Comparing CAD Figure with Processed Image

We propose the recognition method of bridge soldering base metal on the circuits by comparing CAD figure and input image of image processing to locate the soldering iron tip accurately to secure the high quality Firstly, three dimensional CAD assembly drawing of circuits which are assembled perpendicularly in each other is projected on an imaginary two dimensional screen which is vertical to the optical axis of the camera The projected image is used as the standard CAD figure to inspect the location of the bridge soldering base metal. The positions among the bridge soldering base metals show the line state. So this line (connecting line) is used as the reference line to inspect the location of the bridge soldering base metal. The characteristics of the standard figure are represented by the connecting line, edge line and center points of base metal. Secondly, the position and gradient of connecting line among bridge soldering base metals in the input image is estimated. And the position of base metal and assembly accuracy of circuit units are calculated by comparing the shape and position of each base metal with its standard figure based on the connecting line Furthermore, the length between the opposite edges of the base metals are calculated to inspect the positions and the assemble accuracy of circuit units

Ionization of Polycyclic Aromatic Hydrocarbon Molecules around the Herbig Ae/Be environment

We present the results of mid-infrared N-band spectroscopy of the Herbig Ae/Be system MWC1080 using the Cooled Mid-Infrared Camera and Spectrometer (COMICS) on board the 8m Subaru Telescope. The MWC1080 has a geometry such that the diffuse nebulous structures surround the central Herbig B0 type star. We focus on the properties of polycyclic aromatic hydrocarbons (PAHs) and PAH-like species, which are thought to be the carriers of the unidentified infrared (UIR) bands in such environments. A series of UIR bands at 8.6, 11.0, 11.2, and 12.7um is detected throughout the system and we find a clear increase in the UIR 11.0um/11.2um ratio in the vicinity of the central star. Since the UIR 11.0um feature is attributed to a solo-CH out-of-plane wagging mode of cationic PAHs while the UIR 11.2um feature to a solo-CH out-of-plane bending mode of neutral PAHs, the large 11.0um/11.2um ratio directly indicates a promotion of the ionization of PAHs near the central star.Comment: accepted for publication in Advances in Geoscienc

DIMERIC MOLECULAR AGGREGATION MOTIF IN CRYSTAL OF 2,7-DIETHOXY-1-(4-NITROBENZOYL)NAPHTHALENE: CORRELATION OF SINGLE MOLECULAR STRUCTURE, MOLECULAR ACCUMULATION STRUCTURE AND NON-COVALENT-BONDING INTERACTIONS

Crystal structure of 2,7-diethoxy-1-(4-nitrobenzoyl)naphthalene, C21H19NO5, is reported and discussed on the characteristics of the spatial organization of single molecule and molecular aggregation as contrasted with a homologous compound. The molecular structures of these compounds differ only in the kind of alkoxy group of 2,7-positions of naphthalene rings, i.e., ethoxy groups for title compound and methoxy ones for homologue. In single molecular crystal structure, the 4-nitrobenzoyl groups of these molecules are attached non-coplanarly to the naphthalene ring. The congested situation makes bonds connecting naphthalene ring and carbonyl group fixed to turn stereogenetic, which allow the independent existence of atrope stereoisomers of (R)- and (S)-enantiomeric conformer molecules, contrary to their solute state where the fast interconversion disturbs the distinction of the enantiomeric molecules. The two pairs of the enantiomeric molecules are related by two-fold helical axis in the asymmetric unit of P21/n space group for title compound and P21/c for homologous compound, exhibiting the number of molecules (Z) is four for both compounds. In crystal of title compound, (R)- and (S)-enantiomers are connected to each other by pi…pi stacking interaction and two types of C–H…O=N non-classical hydrogen bonds, (sp2)C–H…O=N and (sp3)C–H…O=N non-classical hydrogen bonds along b-axis, forming centrosymmetric dimeric molecular aggregates. The dimeric units are stacked into columnar structure by (sp2)C–H…O=C non-classical hydrogen bonds between molecular unit of identical enantiomeric configuration along a-axis. The columns are also connected by (sp2)C–H…OEt non-classical hydrogen bonds between molecular unit of identical enantiomeric configuration along c-axis to give sheet-like aggregate composed of molecules of same enantiomeric configuration spreading on ac-plane. The sheets are piled up through (sp3)C–H…pi non-classical hydrogen bonds between opposite enantiomeric molecular units of next dimeric aggregates along b-axis. In crystal of the homologous compound, 2,7-dimethoxy-1-(4-nitrobenzoyl)naphthalene, centrosymmetric dimeric aggregate resulted from the association of (R)- and (S)-enantiomers via pi…pi stacking interactions are also observed. The centrosymmetric dimeric aggregates are unidirectionally lined by two kinds of non-classical hydrogen bonds between molecular unit of identical enantiomeric configuration, (sp3)C–H…O=C and (sp3)C–H…pi non-classical hydrogen bonds, giving columnar structure. The columns are accumulated giving a wavy sheet structure composed of stripes of respective enantiomeric configuration oriented alternatively and anti-parallelly through weak (sp2)C–H…pi non-classical hydrogen bonds. The difference of higher ordered structure between title compound and homologue is plausibly explained according to one CH2 margin in 2,7-dialkoxy groups, i.e., elongation of the least length in alkyl group of title compound compared to homologue brings about the sterically significant hindrance among dimeric aggregates that makes rather anisotropic intermolecular non-covalent bonding interactions resulting in accumulating sheet structure. For 1-monoaroylnaphthalene compounds, the most stabilized single molecular structure on condition that the sufficiently effective intermolecular interaction is absent is proposed the perpendicular alignment of naphthalene and benzene rings to prevent the steric repulsion of two aromatic rings. The smaller spatial volume of methyl group in homologue molecule is plausibly able to be merged without large alternation in the single molecular structure most stabilized. Contrarily, the additional methylene unit at 2,7-alkoxy group probably requires the rather large perturbation from the supposed structure most stabilized

Observation of a Highly Spin Polarized Topological Surface State in GeBi2_{2}Te4_{4}

Spin polarization of a topological surface state for GeBi$_2$Te$_4$, the newly discovered three-dimensional topological insulator, has been studied by means of the state of the art spin- and angle-resolved photoemission spectroscopy. It has been revealed that the disorder in the crystal has a minor effect on the surface state spin polarization and it exceeds 75% near the Dirac point in the bulk energy gap region ($\sim$180 meV). This new finding for GeBi$_{2}$Te$_{4}$ promises not only to realize a highly spin polarized surface isolated transport but to add new functionality to its thermoelectric and thermomagnetic properties.Comment: 5 pages, 4 figure

Crystalline Silicate Feature of the Vega-like star HD145263

We have observed the 8-13 $\mu$m spectrum (R$\sim$250) of the Vega-like star candidate HD145263 using Subaru/COMICS. The spectrum of HD145263 shows the broad trapezoidal silicate feature with the shoulders at 9.3 $\mu$m and 11.44 $\mu$m, indicating the presence of crystalline silicate grains. This detection implies that crystalline silicate may also be commonly present around Vega-like stars. The 11.44 $\mu$m feature is slightly shifted to a longer wavelength compared to the usual 11.2-3 $\mu$m crystalline forsterite feature detected toward Herbig Ae/Be stars and T Tauri stars. Although the peak shift due to the effects of the grain size can not be ruled out, we suggest that Fe-bearing crystalline olivine explains the observed peak wavelength fairly well. Fe-bearing silicates are commonly found in meteorites and most interplanetary dust particles, which originate from planetesimal-like asteroids. According to studies of meteorites, Fe-bearing silicate must have been formed in asteroidal planetesimals, supporting the scenario that dust grains around Vega-like stars are of planetesimal origin, if the observed 11.44 $\mu$m peak is due to Fe-bearing silicates.Comment: accepted for Publication in ApJ