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The 13th Symposium on Polar Science/Ordinary sessions [OA] Antarctic meteorites, Thu. 17 Nov.

Samples of the carbonaceous asteroid Ryugu were brought to Earth by the Hayabusa2 spacecraft. We analyzed 17 Ryugu samples measuring 1 to 8 millimeters. Carbon dioxide–bearing water inclusions are present within a pyrrhotite crystal, indicating that Ryugu’s parent asteroid formed in the outer Solar System. The samples contain low abundances of materials that formed at high temperatures, such as chondrules and calcium- and aluminum-rich inclusions. The samples are rich in phyllosilicates and carbonates, which formed through aqueous alteration reactions at low temperature, high pH, and water/rock ratios of

To decrease the temperature at which metallic yttrium (Y) reacts with H2 to form the semiconductor trihydride phase, we employed Pt capping layers as catalysts, and compared the result with those obtained when employing Pd, Ni, or their co-capping layers. It was found that Pt capping with 5 nm thickness makes trihydride phase majority when hydrogenated at 27°C, and allows us to obtain the trihydride phase with approximately 100% molar concentration when hydrogenated at 150 – 200°C. Chemical thermodynamics analysis of the experimental results reveals that both the enthalpy and entropy differences between pure states of trihydride phase and dyhydride phase with hydrogen vapor show monotonic hydrogenation temperature dependencies with their sign inversions at approximately the same temperature around 150°C, suggesting a particular thermodynamic mechanism specific to the hydrogen – yttrium system.

第6回極域科学シンポジウム[OA] 南極隕石11月16日（月） 国立国語研究所 2階 講堂

This paper describes a measurement method for three-dimensional (3D) slit width deviations of long precision slot dies, which are essential for process control in manufacturing. A sensor unit consisting of two laser probes with their measurement axes aligned along the same Z-directional line but with opposite measurement directions, is placed between the two parts of the slot die to scan the two opposing surfaces of the parts along the X- and Y-axes. The variation of the sum of the laser probe outputs, which shows the deviation of the distance between the two surfaces, corresponds to the deviation of the slit width in the Z-direction. The 3D slit width deviations can be obtained accurately through scanning the entire surface in the X Y plane. In addition, the surface flatness of the parts can also be measured accurately by adding one more probe. Measurement experiments have been conducted on a precision grinding machine. The measurement results have indicated that the 3D slit width deviations and flatness can be measured with a repeatability error of less than 1 micron, which meets the requirement for quality control of slot dies.

Ferromagnetic-film-coated carbon nanotube (CNT) probes were employed in a magnetic force microscope (MFM) observation. We succeeded in making a uniform ferromagnetic film on the CNT probes by improving the coating process and selecting materials. The performance of the CoFe-coated CNT probe was evaluated in ultra-high-density perpendicular magnetic storage media with densities from 600 to 1100?k flux changes per inch (FCI). The magnetic domain structure of the magnetic storage media was clearly observed up to 1100?kFCI. The ultimate lateral resolution of the newly developed MFM probes is down to about 10?nm, which exceeds the bit length of a magnetic recording with a density of Tbit?inch?2.

Scanning probe microscope nano-oxidation is carried out on H-passivated Si(0 0 1) surfaces using a humidity control atomic force microscope (AFM) in contact and dynamic modes. To achieve high precision nano-oxidation at large scale, the original tube-scanner-based AFM unit is modified: horizontal movement of the whole sample block (sample stage and the scanner) is operated by an additional XY piezo stage, whilst its vertical movement is controlled by a piezo tube-scanner. The high linearity of the horizontal movement is demonstrated by high resolution oxide patterns which are fabricated after the instrumental modification using standard AFM cantilevers and a modified AFM cantilever with an added carbon nano-tube on tip.

Carbon nanotube-attached atomic force microscope probes were successfully used without nanotube bending to make simultaneous precision nano-oxidation and faradaic current measurements in the dynamic mode. Probe oxidation on H-passivated Si(001) surfaces was carried out by two methods involving vector-scan and raster-scan with a much higher resolution and precision compared to the nanofabrication by standard cantilevers. Faradaic current of the order of a sub-picoampere was detected during nano-oxidation using a carbon nanotube probe, accurately reflecting the subtle difference in the oxidation reaction. The minute current detection through the AFM tip is sensitive enough for the detection of very thin oxides and small-sized features. The dimension of the meniscus during nano-oxidation, which is indispensable for establishing the mechanism model, was evaluated, based on the in situ faradaic current detection and edge broadening.

We have investigated InGaN-based multi-striped orthogonal photon-photocarrier propagation solar cell (MOP3SC) in which sunlight propagates in a direction being orthogonal to that of photocarriers generated by the sunlight. Thanks to the orthogonality, in MOP3SC, absorption of the sunlight and collection of the photocarriers can be simultaneously and independently optimized with no trade-off. Furthermore, by exploiting the degree of freedom along the photon propagation and using multi-semiconductor stripes in which the incoming photons first encounter the widest gap semiconductor, and the narrowest at last, we can convert the whole solar spectrum into electricity resulting in the high conversion efficiency. For processing MOP3SC, we have developed Clean Unit System Platform (CUSP), which turns out to be able to serve as clean versatile environment having low power-consumption and high cost-performance. CUSP is suitable not only for processing devices, but also for cross-disciplinary fields, including medical/hygienic applications.

It is important to obtain an accurate progenitor cell count for estimating the safety and efficiency of cord blood transplantation. Several methods enumerating CD34+ stem and progenitor cells by flow cytometry (FCM) have been reported. In order to estimate the accuracy of these methods, we compared two flow cytometric methods that enumerate absolute CD34+ cell count in cord blood.Forty-one cord blood samples were evaluated by the CD34-SSC and ProCOUNT methods. CD 34-SSC and ProCOUNT gave 15.7±9.6 CD34+ cells/μl and 20.9±10.1 CD34+ cells/μl (mean±1S. D.) in whole cord blood, respectively. In correlation between colony forming units (CFU) and the CD34+ cell count, both methods gave significant correlation coefficient values. The coefficient of variation (CV) in CD34+ cell count by the CD34-SSC method averaged 25.0%, whereas that of ProCOUNT averaged 12.7% (n=8). A statistical difference in CV values was observed between the two methods (p

We propose a standard stepped sample and specify a procedure for determining the step height for height‐scale calibration of atomic force microscopy (AFM) instruments on the order of sub‐nm to nm. The stepped Si(111) surface structure was confirmed to be the most appropriate for the standard sample by a series of round‐robin measurements carried out by a group comprising AFM instrument manufacturers and user organizations. By specifying a standard measurement procedure, the mean standard deviation of the step heights is decreased by 50%. It is also confirmed that the measured Si step height is accurate to ±5%, which is consistent with the accuracy obtained for higher step standard samples. A prototype common data processing software program containing the algorithm of the specified procedure was used to allow direct comparison of the untreated measurement data from each organization.

MFM images of a magnetic head and a recording medium, obtained using electrodeposited FeNi, Co and FeCo tips, show quite different features. These differences are explained by the magnetic properties, saturation magnetization and coercive force of the magnetic thin films electrodeposited on the tungsten wires to form the tips. We attempted to observe the magnetic structure of the tip by using magnetostatic bacteria that swim along the lines of the magnetic field originating from the poles on the tip.

A new scanning tunneling microscope (STM) which can easily search the sample area of interest and can observe the whole area of the sample up to 150 mm diameter has been developed. Its key design feature is the built‐in piezo driver tube, which scans up to 12 μm and is nearly the same size as the objective lens. This tube is located in the revolver of the optical microscope (OM), which has a rotation position reproducibility of better than 1 μm. Tip position can be easily found for comparing the STM and OM images by scanning the standard patterns before measurement. Tip position accuracy of better than 2 μm has been obtained. The whole system, which has a minimum resonance frequency Rf of around 400 Hz, is built on an air damping table (Rf=1.5 Hz) to isolate it from vibrations. However, care must be taken with larger samples because their low resonant frequencies pick up acoustic vibrations more easily. Thermal drift is another problem, as the lengths of the frame holding the piezo driver and the sample s...

A new class of atomic force microscope (AFM) which provides tweezers function in addition to atomic force observation is described. In order to integrate a function of nano-manipulation with AFM, a new micromachined tweezers is developed, named AFM tweezers. This device has two wedged probes at the end of cantilevers; one is used for AFM observation (imaging probe) and the other (movable probe) for grasping a target sample which is just observed by the imaging probe. The mechanical resonant frequency of the imaging probe is higher than that of the movable probe. The integration of both AFM observation and manipulation realizes a successful manipulation of a sample which is by far smaller than the optical microscope's resolution. The movable probe is actuated by an integrated thermal expansion actuator which is operated by a voltage source of up to 30 V and responded up to 10 Hz. The wedge shaped probes were fabricated by combination of anisotropic etching of silicon using KOH solution and local oxidation of silicon (LOCOS) technique. A software for operation of the AFM tweezers is designed, which is installed to SPA400 AFM system (SII Nanotechnology Inc.), the manipulation sequence including approach, grasp, and pick-up is automated.

We fabricated a robust and high aspect ratio tungsten deposited tip (TD tip) using a Focused Ion Beam (FIB). This tip was well controlled during fabrication. Tip diameter is uniform at around 90nm and its growing length is proportional to the irradiation time of the ion beam. Tip shape is a cylindrical pillar and aspect ratio (length/diameter) is greater than 10. Growing angle of the tip is identical to the incident angle of the ion beam. Critical dimension (CD) measurement of shallow trench isolation (STI) was performed using this tip.

The hydroxyethyl starch method and the TopBottom method have been used worldwide for the volume reduction of human placental/umbilical cord blood (PCB) units. To simplify the preparation of nucleated cell (NC) concentrates, we developed a new filter device--the stem cell collection filter system (SCF SYSTEM)--which can collect mononuclear cells (MNC) at a high recovery rate.The SCF SYSTEM consisted of a filter and two bags. Multilayered polyethylene terephthalate non-wovens, coated with a hydrophilic polymer, were used as filter media. PCB units were filtered by gravity (n = 12). Red blood cells, platelets and plasma were drained into the drain bag, and the NC trapped on the filter media was collected in the recovery bag by reverse washing. Recovered cell fractions were evaluated.The volume of cell concentrate recovered was 27.4 +/- 2.2 ml (mean +/- SD, n = 12). The whole time required for processing was less than 30 min, and handling was very simple. The viability of recovered NC was 97.8 +/- 3.2%. The recovery of lymphocytes, monocytes and granulocytes was 79.5 +/- 16.9%, 79.8 +/- 20.4% and 39.0 +/- 19.5%, respectively. The recovery rate of granulocytes was significantly lower than that of monocytes and lymphocytes (Por = 0.0001). The recovery rates of CD3+ cells, CD19+ cells and CD56+ cells were almost the same as that of MNC. The recovery rates of CD34+ cells, total colony-forming cells and long-term culture-initiating cells were 81.7 +/- 27.0% (n = 11), 80.8 +/- 27.7% (n = 12) and 75.0 +/- 18.4% (n = 2), respectively.The new filter system was shown to be efficient for PCB processing, encompassing a very simple handling procedure with a good recovery of haematopoietic progenitor cells. Hence, the SCF SYSTEM is potentially useful for the volume reduction of PCB units for cord blood banking.

An ammonium complex of the hexafluoro cage compound 1 was isolated and its structure was elucidated by X-ray crystallographic analysis. The C-F bonds are elongated by the complexation, which is clear evidence of C-F...cation interaction. The driving force of NH4(+) inclusion is the C-F cation interaction, but the C-F...HN+ hydrogen bond does not contribute to this complexation. The crystal structure of the NH4+ complex 1 shows short C-F...HN+ contacts (2.286-2.662 A). Furthermore, it shows that closer F...H(+)(-N) distances give a larger F...H(+)-N angle. Although such structural features seem to indicate the existence of C-F...HN+ hydrogen bonds, the spectral data (1H NMR, 19F VT-NMR, and IR spectroscopy) did not support the existence of hydrogen bonds. Thermodynamic parameters, log K(s) (4.6 +/- 0.1, 298 K), deltaH (-5.3 +/- 0.1 kcal mol(-1)), and deltaS (3.2 +/- 0.3 cal mol(-1) K(-1)), of the complexation were obtained in CDCl3/CD3CN mixture.

Alpha1-adrenoceptor (alpha1-AR) stimulation increases sarcolemmal Na+-H+ exchanger (NHE) activity. The present study was designed to determine the role(s) of alpha1-AR subtype(s) in mediating this response. As an index of NHE activity, acid efflux rates (JHs) were determined in single rat ventricular myocytes loaded with the pH-sensitive fluoroprobe carboxy-seminaphthorhodafluor-1 after 2 consecutive intracellular acid pulses in bicarbonate-free medium. JH at pHi 6.90 did not change significantly during the second pulse relative to the first in control cells but increased in a dose-dependent manner when the second pulse occurred in the presence of phenylephrine (nonselective alpha1-AR agonist) or A61603 (alpha1A-AR-selective agonist), with EC50 values of 1.24 micromol/L and 3.6 nmol/L, respectively (both agonists given together with 1 micromol/L atenolol). Stimulation of NHE activity by 10 micromol/L phenylephrine was inhibited in a dose-dependent manner by the competitive antagonists prazosin, WB4101, and 5-methylurapidil, with IC50 values of 12, 32, and 149 nmol/L, respectively. Analyses of the relative EC50 and IC50 values obtained (and Ki values estimated from the antagonist IC50s) in relation to the relative potencies of these agents at native rat alpha1-AR subtypes and their relative affinities for recombinant rat alpha1-ARs suggest that alpha1-adrenergic stimulation of sarcolemmal NHE activity is likely to be mediated selectively by the alpha1A-AR.

The technology for storage of red blood cells and platelets are quite important for the production of safe blood products and their supply. The usage of additive solution rather than plasma can improve the storage condition of red blood cells and allow more plasma recovered for plasma fractionation. Autologous transfusion is increasing extensively in these days, and the interest in a prolonged storage of cells has been growing. The use of synthetic media for platelet storage is expected to increase in the future and research is undergoing extensively worldwide. Further study is required to find the better ways to extend the storage period with high quality of cellular functions.

Stimulation of myocardial alpha 1 adrenoceptors causes (1) exacerbation of reperfusion induced arrhythmias, and (2) stimulation of sarcolemmal Na+/H+ exchange. The aims of this study were to identify the alpha 1 adrenoceptor subtype involved in the former effect and to determine whether stimulation of the Na+/H+ exchanger may play a role in this phenomenon.Isolated rat hearts were subjected to independent perfusion of the left and right coronary beds. After 15 min of aerobic perfusion of both beds, the alpha 1 adrenoceptor agonist phenylephrine (0.1, 1, or 10 microM) was infused selectively into the left coronary bed for 2 min. The left coronary bed was then subjected to 7 min of zero flow ischaemia and 5 min of reperfusion.The incidence of reperfusion induced ventricular fibrillation was increased from 0% in controls to 8%, 42%*, and 75%* with 0.1, 1, and 10 microM phenylephrine (*P0.05); this dose dependent effect occurred in the absence of significant intergroup differences in vascular resistance or heart rate. Similar infusion of methoxamine at 10 microM also increased the incidence of reperfusion induced ventricular fibrillation from 13% to 88%*. Infusion of 10 microM phenylephrine during reperfusion alone did not affect the incidence of reperfusion induced ventricular fibrillation. Infusion of the selective alpha 1A adrenoceptor antagonist WB4101 at 0.1, 1, or 10 microM for 2 min immediately before ischaemia (concomitantly with 10 microM phenylephrine) reduced the incidence of reperfusion induced ventricular fibrillation from 83% to 75%, 25%*, and 0%*. Similar infusion of the selective alpha 1B adrenoceptor antagonist chloroethylclonidine (0.1 or 1 microM) or the selective beta 1 adrenoceptor antagonist atenolol (0.1 or 1 microM) did not reduce the incidence of reperfusion induced ventricular fibrillation. The novel NHE-1 selective Na+/H+ exchange inhibitor HOE694 (10 microM), when infused into the left coronary bed before ischaemia (concomitantly with 10 microM phenylephrine) and throughout reperfusion, reduced the incidence of reperfusion induced ventricular fibrillation from 83% to 25%*. In hearts that received 10 microM phenylephrine before ischaemia. HOE694 (10 microM) was partially effective when infused during reperfusion alone (ventricular fibrillation incidence reduced from 83% to 42%).(1) the exacerbation of reperfusion induced arrhythmias by alpha 1 adrenergic stimulation during ischaemia is mediated by the alpha 1A adrenoceptor subtype, and (2) increased Na+/H+ exchanger activity during ischaemia and reperfusion may play a causal role in this phenomenon.

Activation of sarcolemmal Na+/H+ exchange has been proposed as a causal factor in reperfusion arrhythmogenesis. To test this hypothesis, we determined the antiarrhythmic efficacy of two structurally distinct but equipotent Na+H+ exchange inhibitors, 5-(N-ethyl-N-isopropyl)amiloride (EIPA) and the novel drug, 3-methylsulfonyl-4-piperidinobenzoyl guanidine (HOE-694), in isolated rat hearts (n = 12/group) subjected to independent dual coronary perfusion. After 15 min of aerobic perfusion of both beds, flow to the left coronary bed (LCB) was terminated for 10 min; this was followed by 5 min of reperfusion. Various concentrations of each drug were selectively infused into the LCB either during the 5-min period preceding ischemia plus during reperfusion or during reperfusion alone. With the former protocol, 0.01, 0.1, 1, and 10 microM EIPA reduced the incidence of reperfusion-induced ventricular fibrillation (VF) from 92% in controls to 83, 83, 50, and 0% (P < 0.05); the number of hearts in sinus rhythm at the end of reperfusion was increased from 17 to 42, 25, 83 (P < 0.05), and 100% (P < 0.05). HOE-694, at the same concentrations, reduced VF incidence from 92% in control to 83, 58, 50, and 8% (P < 0.05); 25, 67, 75 (P < 0.05), and 100% (P < 0.05) of hearts were in sinus rhythm, compared with 17% of controls, at the end of reperfusion. Even when infused during reperfusion alone, both drugs afforded significant protection against reperfusion-induced VF, which did not differ significantly from that observed when the drugs were also given before ischemia. The similar antiarrhythmic efficacy of EIPA and HOE-694 is consistent with an arrhythmogenic role for activation of Na+/H+ exchange during early reperfusion.

To evaluate the prognostic and clinical significance of silent myocardial ischemia (SMI), we examined cardiac events in 160 patients with old myocardial infarction who underwent ambulatory Holter monitoring, treadmill exercise testing and coronary angiography. Using the Cox's proportional hazard regression model and the survival curves with the Kaplan-Meier method, we identified the predictors of cardiac events. The incidence of cardiac events for all the patients during the 44-month follow-up period was 18%. The significant predictors of unfavorable outcomes were severe coronary lesions and SMI. The incidence of SMI was 38%. The cardiac event rate in patients with SMI was higher than in those without SMI (32 vs 9%, p0.05). The most frequent cardiac event in patients with SMI was reinfarction, and the significant predictors of cardiac events for these SMI patients were lower ejection fraction and maximum ST depression on Holter monitoring. In conclusion, SMI proved to be a significant predictor of unfavorable outcome in patients with old myocardial infarction. It was, therefore, suggested that revascularization (PTCA/CABG) should be used as early as possible in patients with SMI whether anginal symptoms are present or not.

We presented here a case of mitral stenosis developing infective endocarditis 18 months after PTMC. A 33-year-old male was admitted to our hospital for the evaluation of mitral stenosis with signs of congestive heart failure. The use of PTMC was adequately indicated based on the data of previous cardiac catheterization and was successfully performed. The post-operative clinical course was good leaving only slight mitral regurgitation demonstrated by post-valvuloplasty LVG. About 18 months after PTMC, the patient developed a high fever and erythema with tenderness on his leg, so he was admitted again. Blood culture was positive for streptococcus viridans. Moreover, echocardiogram revealed valvular vegetation on the anterior mitral leaflet, which is the characteristic finding of infective endocarditis. Antibiotics were so effective that his clinical course was relatively good with minor cerebral infarction during chemotherapy. Little is known about the prognosis and late complication of PTMC. However, our reported case may suggest that prophylactic chemotherapy might be recommended at least in some cases showing mitral regurgitation after PTMC.

To evaluate the clinical significance of asymptomatic ischemic heart disease, exercise electrocardiography and stress myocardial scintigraphy were performed. These were correlated with symptoms during exercise tests and histories of myocardial infarction (MI). The study subjects consisted of 70 patients with coronary artery disease, including 34 with MI, and 36 without MI but with angina pectoris. Stress tests were performed using bicycle ergometer under electrocardiographic monitoring throughout the test. Transient myocardial ischemia was confirmed by perfusion defects on thallium myocardial imaging demonstrated immediately after exercise, but not 3 hours after the stress test. Asymptomatic ST depression was observed in 18 of 34 patients with MI (53%) and in 21 of the 36 patients with angina (58%); however, transient myocardial perfusion defects were confirmed in 61% of the patients with MI (11 of 18 patients), but in only 33% of those with angina (7 of 21 patients). The difference was statistically significant (p less than 0.05). It was suggested that there are some differences in the clinical significance of asymptomatic ST depression between the patients with MI and those without MI but with angina pectoris.

CoFe-coated carbon nanotube (CNT) probes have been successfully fabricated by a radio-frequency sputtering method. The sputtering conditions for obtaining a uniform ferromagnetic film on the CNT probe were investigated. The optimal sputtering conditions were determined from the observations using a scanning electron microscope and an atomic force microscope. CNT magnetic force microscope (MFM) probes prepared under optimized conditions provided us clear images with an ultimate lateral resolution of approximately 10 nm.

Microroughness, which accompanies the miniaturization of device dimensions, is essential to the reliability of the device. The atomic force microscope (AFM) is available as a Si microroughness evaluation apparatus but most models cannot measure large size wafers in an environment with a lot of disturbance, such as a clean room. The AFM used for the measurement is a lever scan type in which a small scale optical lever defection detector and cantilever are installed at the top of a tube piezoscanner, and is linked to an optical microscope. It can accurately position within 4 μm on up to an 8 in. sample. The performance of this system includes a lateral resolution of approximately 5 A and a Z direction resolution of about 0.5 A. The CZ P‐type (100) size 4 in. wafer used in the measurement is oxidized after three types of washing, and the relationship between the roughness of the bare wafer and the roughness of the oxidized wafer is measured.

This paper details a new heuristic-based method for optimizing system availability by redundant allocation. Hot or cold standby, majority voting, repair crew, or other type of logic systems are easily handled. A computer program, Upgrading of System Availability Package (USAP), has been developed and is available from the authors. This program assesses and upgrades system availability when the component availability and system configuration are known, If the system availability needs to be improved and funds are available for such an improvement, then USAP suggests a system configuration that has the desired system availability within a given cost constraint. The algorithm is based on cut sets, so both fault trees and block diagrams can be handled. No special subroutines which specify the functional form of the system availability are required. This makes the program easy to implement on a personal computer, since no linking and compiling of special routines are needed. The upgrading program in USAP provides good results as compared to other upgrading methods found in the literature. This simple and intuitive analysis gives practical solutions for very large, complicated systems.

The temporal coherence of the output from a Q-switched ruby laser is investigated by using single-exposure holography of a rotating plate object. The whole profile of the temporal coherence is obtained as a function of the velocity of the rotating object, instead of the time difference between the reference beam and object beam. Furthermore, it is shown that the coherence time is almost proportional to the inverse of the total frequency shift.

The frequency sweep of the output from a Q -switched ruby laser is investigated by using a holographic technique of a moving object. The chirp rate of the frequency sweep is assumed to be linear in time. We also propose how to measure in a single-exposure hologram the temporal coherence of the same laser.

Many important contributions have been recently made, to our knowledge, to the analysis of organic compounds using LDMS or SIMS. Most of these works have been carried out on specific samples such as thin layer compounds deposited on a metal surface [1]. Recently, characteristic secondary ions (SI) of various kinds of practical polymer films were shown by Briggs [2, 3]. In his paper, the importance of surface potential stabilization attained by selecting the optimum parameters for primary ions and electron flood was emphasized to obtain finger print SI mass spectra of individual polymers.

Recent trends show polymeric materials being used in more electronic parts. In these applications, surface, interface, and small area analysis as well as bulk analysis, are of increasing importance.