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Scanning surface probes delivered from atomic force microscopy (AFM) are expected to investigate local electrostatic properties on insulating surfaces by forces. Electrostatic force spectroscopy is especially suitable to clarify the capacitive interaction. In order to perform it at a well-defined tip-surface separation, we developed a dynamic mode, in which the tip-surface separation is regulated by maintaining the cantilever oscillation amplitude with an active feedback, while the electrostatic force gradient is simultaneously detected with a variable resonant frequency shift. Using the method, it turns out that the quadratic dependence of the electrostatic force gradient on an applied bias observed on an insulating Al(2)O(3)(0001) is comparable to those on a metallic Au(111). It results from the potential difference between the tip and the insulator surface being only one order smaller than that between the tip and the metal surface despite the spacing between electrodes for the insulator being 10(6) times larger than for the metal, because the capacitive interaction is modified primarily between the sharp AFM tip and the surface.

In general, gene-dependent translational progress affects the efficiency of protein expression. To evaluate the translational progress of protein synthesis, it is necessary to trace the time course of translation as well as the quantity of products. Here we present a new method for tracking translation steps in cell-free protein synthesis using atomic force microscopy (AFM). The cell-free protein synthesis system is useful to track the inherent translational progress of a target gene, whereas conventional UV absorption measurement coupled with density gradient fractionation is difficult to analyze such small sample quantities. Because the high resolution of AFM enables us to clearly count the number of ribosomes included in polysomes, polysome profiles can be obtained directly without complicated fractionation. With this method, we could elucidate the detailed polysome profile with only 1 microl of sample solution. We observed the translational progress of green fluorescent protein synthesis, a model of high-expression protein, as well as human retinoid X receptor. Detailed polysome profiles showed different patterns of translational progress and were clearly associated with the results of time-dependent protein expression. Our study suggests the possibility for comprehensive character analysis of inherent gene-dependent translational progress.

Oxidation of a directly meso-meso linked cyclic porphyrin tetramer 2 gave a porphyrin sheet 3. The symmetric square structure of 3 is indicated by its simple 1H NMR spectrum that exhibits only two signals for the porphyrin beta-protons. The absorption spectrum of 3 displays characteristic Soret-like broad bands and weak Q-bands, and its magnetic circular dichroism (MCD) spectrum exhibits a negative Faraday A term at the 762 nm band as a rare case, indicating the absorption as a transition from a nondegenerate level to a degenerate level. A slightly longer S1-state (1.1 ps) and smaller TPA cross section (2750 GM) than a tetrameric linear porphyrin tape also indicate its unique electronic properties. The porphyrin sheet 3 forms stable 1:2 complexes with guest molecules G1 and G2, whose 1H NMR spectra exhibit remarkable downfield shifts for the guest protons that are located just above the cyclooctatetraene (COT) core of 3, whereas the imidazolyl protons bound to the zinc(II) porphyrin local cores are observed at slightly upfield positions. These results have been qualitatively accounted for in terms of the presence of a strong paratropic ring current around the COT core that propagates through the whole pi-electronic network of 3, hence competing with and cancelling the weak diatropic ring currents of the local zinc(II) porphyrins. This explanation was supported by DFT calculation performed at the GIAO-B3LYP/6-31G level, which indicated large positive NICS values within the COT core and small NICS values within the local zinc(II) porphyrins.

Starting from a 1,3-phenylene-linked diporphyrin zinc(II) complex 2ZA, repeated stepwise Ag(I)-promoted coupling reactions provided linear oligomers 4ZA, 6ZA, 8ZA, and 12ZA. The intramolecular cyclization reaction of 12ZA under dilute conditions (1x10(-6) M) gave porphyrin ring C12ZA with a diameter of approximately 35 A in 60% yield. This synthetic strategy has been applied to a 1,3-phenylene-linked tetraporphyrin 4ZB to provide 8ZB, 12ZB, 16ZB, 24ZB, and 32ZB. The intramolecular coupling reaction of 24ZB gave a larger 24-mer porphyrin ring C24ZB with a diameter of approximately 70 A in 34% yield. These two large porphyrin rings were characterized by means of 1H NMR spectroscopy, matrix-assisted laser desorption ionization time-of-flight (MALDI-TOF) mass spectroscopy, UV-visible spectroscopy, gel permeation chromatography (GPC) analysis, and scanning tunneling microscopy (STM) techniques. The STM images of C12ZA reveal largely circular structures, whereas those of C24ZB exhibit mostly ellipsoidal shapes, indicating more conformational flexibility of C24ZB. Similar to the case of C12ZA, the efficient excitation energy transfer along the ring has been confirmed for C24ZB by using the time-correlated single-photon counting (TCSPC) and picosecond transient absorption anisotropy (TAA) measurements, and occurs with a rate of (35 ps)(-1) for energy hops between neighboring tetraporphyrin subunits. Collectively, the present work provides an important step for the construction of large cyclic-arranged porphyrin arrays with ample electronic interactions as a model of light-harvesting antenna.

Directly meso-meso linked porphyrin rings CZ4, CZ6, and CZ8 that respectively comprise four, six, and eight porphyrins have been synthesized in a stepwise manner from a 5,10-diaryl zinc(II) porphyrin building block. Symmetric cyclic structures have been indicated by their very simple (1)H NMR spectra that exhibit only a single set of porphyrin and their absorption spectra that display a characteristic broad nonsplit Soret band around 460 nm. Energy minimized structures calculated at the B3LYP/6-31G* level indicate that a dihedral angle between neighboring porphyrins decreases in order of CZ6CZ8CZ4, which is consistent with the (1)H NMR data. Photophysical properties of these molecules have been examined by the steady-state absorption, fluorescence, fluorescence lifetime, fluorescence anisotropy decay, and transient absorption measurements. Both the pump-power dependence on the femtosecond transient absorption and the transient absorption anisotropy decay profiles are directly related with the excitation energy migration processes within the porphyrin rings, where the exciton-exciton annihilation time and the polarization anisotropy rise time are well described in terms of the Forster-type incoherent energy hopping model. Consequently, the excitation energy hopping rates have been estimated for CZ4 (119 +/- 2 fs)(-)(1), CZ6 (342 +/- 59 fs)(-)(1), and CZ8 (236 +/- 31 fs)(-)(1), which reflect the magnitude of the electronic coupling between the neighboring porphyrins. Overall, these porphyrin rings serve as a well-defined wheel-shaped light harvesting antenna model in light of very efficient excitation energy hopping along the ring.

Background The significance of higher intercostal space electrocardiography (HICS ECG) for the detection of the Brugada sign was investigated. Methods and Results The subjects consisted of 113 cases (108 males, 5 females; mean age, 57±17 years) with incomplete right bundle branch block type QRS morphology and ST-segment elevation (>0.10 mV) in the right precordial leads. Obvious structural heart disease was not observed in any of the subjects. The V1-3 leads of the standard 12-lead ECG and the HICS ECG were recorded in the supine position, and the amplitude of the terminal portion of the QRS (J-point) and ST-segment (80 ms from the J-point) were measured. In the HICS ECG, there was an increase in the area in which the Brugada sign was detectable (47 leads to 66 leads), and in cases with the Brugada sign, the amplitude of the J-point increased. Conclusions The HICS ECG may be helpful for the detection of the Brugada sign. (Circ J 2004; 68: 1018 - 1022)

A new system of synthesizing a 12-lead electrocardiogram (Syn-ECG) with practically identical waveforms to the standard 12-lead ECG (Stn-ECG) from 3-channel ECGs recorded by Holter monitoring has been developed.The study group comprised 16 healthy individuals and 13 patients with abnormal ECGs. The bipolar eV1, eV5 and eVF leads were recorded using digital Holter monitoring and nine Syn-ECGs, corresponding to each lead of the Stn-ECG, were synthesized. The 9 ECGs consisted of a theoretical Syn-ECG and 8 Syn-ECGs positioned around the theoretical Syn-ECG at 3 cm intervals on the Frank's image surface. Of the 9 ECGs, the Syn-ECG with the maximum product of the cross-correlation coefficient of the QRS wave and that of the T wave, was automatically selected as the optimal Syn-ECG. The amplitude data from the QRS wave, R wave, T wave, and ST level, and also the amplitude ratio of the R wave, T wave to the QRS wave, were significantly well correlated between the Syn-ECG and Stn-ECG.A practically identical ECG morphology, comparable with a Stn-ECG, was successfully created using this system.

A dodecameric porphyrin wheel was prepared by Ag(I)-promoted intramolecular coupling of a linear porphyrin dodecamer and was observed by scanning tunneling microscopy (STM). Efficient energy hopping along the array was revealed by femtosecond transient anisotropy measurements.

Geometrical structures of chain porphyrin arrays adsorbed on Cu(100) are observed by STM: a bridge-like bent structure for meso-meso singly linked orthogonal hexamer, whereas a rigid planar and one-dimensionally stacked structure for meso-meso, beta-beta, beta-beta triply-linked hexamer.

The autonomic properties in 27 patients with the electrocardiographic morphology of Brugada syndrome were investigated using 24-h Holter monitoring: 10 patients had a history of ventricular fibrillation (VF; Br-VF group) and 17 did not (Br-N group); there were 26 healthy subjects enrolled in this study. All subjects underwent normal Holter data monitoring and power spectral analysis. Few extrasystoles were observed in either group, and the mean heart rate (HR), maximum HR, and total heart beats over 24 h were obtained. All of these measurements were significantly lower in the Br-VF group than in the Br-N and healthy subject groups. The RR interval variability was analyzed over 512 beats every 10 min. The high-frequency component (0.15-0.40 Hz; HF), low-frequency component (0.04-0.15 Hz; LF) and the LF/HF ratio were analyzed over 24 h. The HF was significantly higher and LF/HF ratio lower in the Br-VF group than in the healthy subjects. The HF was also significantly higher than in the Br-N group. During the night (00.00-05.00 h), the HF was significantly higher in the Br-VF group, and the LH/HF lower. During the day (12.00-17.00 h), the HF was significantly higher in the Br-VF group, but there was no difference in the LF/HF. These results indicate that high vagal tone and low sympathetic tone are specific properties of symptomatic Brugada syndrome. (Circ J 2003; 67: 511 - 514)

A 67-year-old female with recurrent syncope and no obvious heart disease developed ventricular dysfunction, known as takotsubo cardiomyopathy, following a 90 s episode of polymorphic ventricular tachycardia originating from a ventricular extrasystole with a short coupling interval. Cardiac catheterization performed 30 min after the arrhythmic event revealed angiographically normal coronary arteries, and left ventricular apical akinesis and basal hyperkinesis. An intracoronary injection of acetylcholine revealed no inducible coronary spasm, and an electrophysiological study revealed normal atrioventricular conduction and no inducible ventricular arrhythmia. Thirty hours after the arrhythmic event, electrocardiography revealed deeply inverted T waves in leads V3 to V6, I, and aVL, which continued for more than a week. Although no treatment was given to maintain hemodynamic stability, echocardiography revealed normal left ventricular contraction 14 days after the onset of the ventricular dysfunction. The reversible ventricular dysfunction might have been induced by altered catecholamine dynamics due to the persistent syncope during the occurrence of tachycardia.

KISHI, R., et al.: Influence of Mobile Magnetic Resonance Imaging on Implanted Pacemakers.Purpose: Mobile magnetic resonance imaging (MRI) systems will be widely used in Japan. When traveling, mobile MRI generate alternating electromagnetic waves which may cause electromagnetic interference (EMI). This study was designed to determine whether this may influence the function of implanted pacemakers (PM). Methods and Results: The influence of the static magnetic fields was tested in the first method using a PM-human model (Phantom). Magnetic force was simultaneously measured. The PM was switched to the magnet mode within 90 cm from the vehicle, where the magnetic force was = 2 mT. In the second method, six phantoms were placed on the side of the road, facing in three different directions in X-Y-Z axis orientations, at 1.3 m and 2.0 m above the ground. The mobile MRI passed by at a distance of 1 m from the phantoms at the speed of 20 or 40 km/h. In these experiments, magnet mode switch of the PM was observed for 2 seconds when the vehicle passed close to the phantoms, though no electrical noise was recorded. Conclusion: Mobile MRI vehicles can switch a PM to magnet mode when the distance between patient and vehicle is

A 70-year-old woman with a past history of cholecystolithiasis was admitted to a local clinic because of right hypochondralgia with back pain. Since physical examination revealed Murphy's sign, this patient was diagnosed as acute cholecystitis. The ultrasonographic examination of the gallbladder showed a stone of the cystic duct with no definitive wall thickening. CT scan revealed dissection of the abdominal aorta. She was then referred to our hospital for further examinations. She was observed in the cardiac care unit to determine whether the aneurysm and cholecystitis were in an acute or chronic state. Blood examinations and enhanced CT scan showed that her clinical symptoms originated not from cholelithiasis but from acute closing aortic dissection, Stanford classification type B. Close cooperation with a highly developed medical facility is essential when diagnosing elderly patients with symptoms open to a variety of interpretation.

This paper investigates the roles of a solution (decane) in deoxyribonucleic acid (DNA) observation with a scanning tunneling microscope. Our study indicates that decane prevents continuous water adsorption from air and subsequent ionization of the water to create specific conditions for DNA observation. Analysis of the tunneling current reveals that the current with decane became twice as stable in deviation and the current is sustained 1 nm further in the z-direction than without decane. The apparent barrier height with decane is also decreased by a factor of 0.18. These properties enable us to measure bulky DNA (4 nm) at the highest success ratio ever attained.

We present electrostatic force microscopy images of double-stranded DNA and transcription complex on an insulating mica substrate obtained with molecular resolution using a frequency-mode noncontact atomic force microscope. The electrostatic potential images show that both DNA and transcription complexes are polarized with an upward dipole moment. Potential differences of these molecules from the mica substrate enabled us to estimate dipole moments of isolated DNA and transcription complex in zero external field to be 0.027 D/base and 0.16 D/molecule, respectively. Scanning capacitance microscopy demonstrates characteristic contrast inversion between DNA and transcription complex images, indicating the difference in electric polarizability of these molecules. These findings indicate that the electrostatic properties of individual biological molecules can be imaged on an insulator substrate while retaining complex formation.

Water-soluble gold nanoparticles were immobilized in both polar (water) and nonpolar (chloroform) liquids on hydrophilic mica surface by oxygen plasma ashing. It is then demonstrated that a DNA with a thiol at an extremity is attached to the immobilized nanoparticles due to the gold-thiol coupling and stretched in the flow direction of the following water rinse. This technique allows a sequential integration of nanoparticles and molecules for various solutions, since the nanoparticles remain on a solid surface rather than dissolve into the solution.

The purpose of the present paper is to reveal the distribution and change of voting returns in the elections to the House of Councilors (National Constituency), and to examine the relation between the voting returns and regional socio-economic characteristics in Aichi Prefecture. For that purpose, (1) voting ratios and polls to each political party were calculated in order to examine the distribution and change of voting returns between the 7th election (1965) and the 10th election (1974), (2) factor analysis was applied to 38 variables selected for regional socio-economic characteristics and their changes in Aichi Prefecture both in 1965 and 1975, and (3) the relations between factor scores and voting returns were analysed by multiple regression analysis. The study area contains 101 wards, cities, towns and villages in Aichi Prefecture (Fig. 1). The results obtained from these analyses are summarized as follows: 1. In the 7th election, the voting ratio was higher in rural and mountainous areas and lower in urban areas, which was also the tendency held in the 10th election (Fig. 2-a, b). The polls of the Jimin Party (Liberal-Democratic Party, L. D. P.) were more numerous in rural and mountainous areas and less so in urban areas in the 7th election. The polls of the L. D. P, decreased in the 10th election (Fig. 2-c, d). The percentage of polls of the Shakai Party (Japan Socialist Party, J. S. P.) were higher in urban areas in the 7th election, because the J. S. P. was supported by a number of labour unions. The J. S. P.'s polls decreased, however, in urban areas in the 10th election (Fig. 2-e, f). The Komei Party, the Minsha Party (Democratic-Socialist Party, D. S. P.) and the Kyosan Party (Japan Communist Party, J. C. P.) secured more votes in urban areas than in rural and mountainous areas in the 7th election, and they received more votes from urban areas in the 10th election than in the 7th election (Fig. 2-g-1). The Komei Party and the J. C. P. won more votes in Nagoya City and its suburbs, and their polls increased there between the 7th and 10th elections. The D. S. P, is supported by such labour unions as fiber industries and the Toyota Automobile Company Ltd. and its allied companies. Therefore the D. S. P, polled more votes where those companies were located than other areas. 2. Eight factors for 1965 and nine factors for 1975 were extracted by the factor analysis. Based on the eigen values above unity, the cummulative percentage to the total variance was 83.8% and 85.4% respectively (Tables 2 and 3). The maj or dimension thus extracted was employment types (38.1%) for 1965, which had high factor loading to many variables and showed general characteristics of urban-rural extent. As for 1975 some factors showing commercial activities as well as density, increase, and constitution of population had high percent of explanation. Those analyses suggest that industries have dispersed and the regional difference of the tertiary industries has become notable during ten years. 3. The results of multiple regression analysis suggest that there is a close relation between the voting ratios and the socio-economic characteristics (Table 4). As to the 7th election, the voting ratios were generally explained by the first factor, while the factors to explain the 10th election's voting ratios varied greatly from one party to another. Most residuals from the multiple regression model were explained by the organized polls of labour unions especially in J. S. P. and D. S. P. and by the personal polls of influential members.

多ピンSMDによるバスラインの増加や, 両面実装化, 高密度実装化に伴い配線設計は複雑化している。従来からPWB配線設計に用いられている等間隔のグリッドをベースとしたルータでは, これらのPWBには対応することが困難である。本論文では, SMD等の多種のピンピッチ部品に対応するために, 異形状グリッドを用いた一層および多層配線可能な迷路法ルータを開発した。また, 本ルータは人手設計に近い性能をもたせるため, トップダウンな階層的処理を行い, バスラインを大局的見地から考慮して配線する。そして, 将来的には専用ハードウェア化も可能なアルゴリズムである。実験の結果, グリッド数が従来の固定グリッドベースのものと比べ, 約1/20となり処理の高速化が望める。バスを束線としてまとめて配線するため, コンパクトな配線が実現され, SMDを搭載した基板に対し95%程度の配線率が得られた。