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Nuclear moment studies on nuclei situated far from the β-stability line, performed by taking advantage of the projectile fragmentation reaction, are reviewed. A method to produce spin polarization/alignment in the projectile fragments was developed and utilized for the β-NMR/NQR measurements. Several new findings in nuclear structure physics were obtained from the nuclear moment experiments done with these techniques.

Nylon-6,6 vesicles are synthesized by the interfacial polycondensation of hexamethylenediamine and adipoyl chloride in microgravity, and their size and shape are compared with those formed in normal gravity. Two methods are applied for the nylon syntheses. First, a carbon tetrachloride solution of adipoyl chloride (AC) is sprayed into an aqueous solution of hexamethylenediamine (HD) in a reaction column from the nozzle at the bottom of the column, and inversely HD solution is sprayed into the AC solution column. Nylon vesicles containing the solvent inside are formed. In the second method, both of the reaction solutions are sprayed in an air column and the reaction proceeds by the collision of both mists. For both methods, the reaction is followed by the transmitted-light intensity of the reaction mixture. Furthermore, the products are analyzed by microscopic observation. The nylon vesicles were not completely spherical in most cases, even if formed in microgravity. However, the size and the aspect ratio of the vesicles in microgravity are always smaller than those in normal gravity.

We report experimental results of an eddy current test. When an excitation coil is brought close to a conductor, an eddy current is induced in the conductor. If there is a crack in the conductor, the eddy current will avoid that area, causing variation in the magnetic field generated by the eddy current. We examined how effectively the differential motion method could be used to detect the magnetic field change through the output voltage difference between two coils. We report characteristics of detecting coil output voltage and phase difference characteristics between excitation current and the output voltage and frequency characteristics of the detecting coil output voltage.

Rotational relaxation times (τ) of anisotropic tungstic acid colloids (3.24 μm in major axis) in aqueous suspension are measured in microgravity (0G), normal gravity (1G) and at 2G. The measurements at 0G and 2G are achieved by parabolic and circular flights, respectively. The limiting slopes of the relaxation curves in the plots of the transmitted light intensity against time are close to zero at 0G irrespective of the flow directions in the flow cell, whereas those at 1G and especially at 2G depend on the flow direction by the convection of the suspension and particle sedimentation. Experimental errors at the τ values at 0G are small compared with those at 1G and 2G, which is ascribed to the lack of movement of impurities in the suspension such as quite small air bubbles, which cannot be recognized with the naked eye, and the convection of the suspension in microgravity. More reliable rotational relaxation times are obtained in microgravity; however, the relaxation times themselves are quite insensitive to gravity. Theτ values observed are larger than those calculated from the particle size, which indicates the important contribution of the electrical double layers formed around the colloidal particles.

Rotational relaxation times (τ) of anisotropic tungstic acid colloids in aqueous suspension containing sodium chloride or ethyl alcohol are studied in microgravity achieved by free-fall experiments. Experimental errors at 0 G, in many cases, are small compared with those at 1 G, which is ascribed to the lack of the convection of suspension in microgravity. Much more reliable data of the diffusion coefficients are obtained in microgravity. The limiting slopes of the relaxation curves in the plots of the transmitted-light intensity against time at 1 G depend on the flow direction of the suspension in the flow cell, whereas those at 0 G are close to zero irrespective of the flow direction. Sodium chloride decreases τ, whereas ethanol addition increases this time. These effects are ascribed to the thinning of the electrical double layers and to the increase in the suspension viscosity.

Rate coefficients (k) in the colloidal crystallization of monodispersed silica spheres in the presence of sodium chloride are studied in microgravity achieved by parabolic flights of an aircraft. Time-resolved reflection spectroscopy is made with a continuous circulating-type stopped-flow cell system. The k values decrease as the salt concentration increases both at 0 and 1 G and those in microgravity are smaller than those in normal gravity by 16% (maximum), especially in water and in the presence of a small amount of the salt lower than 2 × 10−6 mol/l. The rates in flight at 1 G are larger by 15% (maximum) compared with those at 1 G on the ground. The k values obtained at 0 G, 1 G in flight and 1 G on the ground agree excellently with each other for the suspensions with 3 × 10−6 and 4 × 10−6 mol/l sodium chloride. Disappearance of the downward diffusion of spheres and no convection of the suspensions are important for retardation in microgravity.

Nuclear spin maser based on a new masing mechanism is proposed, which is applicable to high-precision measurements of the electric dipole moment of neutron. To test this idea, a spin maser with a spin-polarized 129Xe gas as a working substance was constructed. After a detailed investigation of the spin maser operation in an ordinary spin-masing mechanism, we introduced an additional component in the feedback loop of the maser in order to implement the proposed masing mechanism. A self-sustained oscillation of transverse spins has been observed which clearly indicates a realization of spin masing arising from the new masing mechanism.

Rotational relaxation times (τ) and diffusion coefficients of ellipsoidal colloids of tungstic acid are studied in aqueous suspension in microgravity by free-fall experiments. τ values are evaluated from the relaxation traces of the optical transmittance of the suspension using the stopped-flow technique. Experimental errors at 0 G are small compared with those at 1 G, which is ascribed to lack of the movement of impurities in suspension such as quite small dust and bubbles and the convection of the suspension in microgravity. The limiting slopes of the relaxation curves in the plots of the transmittance against time at 1 G depend on the flow direction of the suspension in the flow cell, whereas those at 0 G remain zero irrespective of the flow direction. For more reliable diffusion coefficients are obtained in microgravity; however, the diffusion coefficients themselves are quite insensitive to gravity.

A major problem in the electric power industry is distribution-line degradation. Nondestructive detection of cracks in a distribution line may be possible through eddy-current testing or measurement of the magnetic field around the distribution line when it is energized. We have examined each of these methods, eddy-current testing and distribution of the magnetic field around a conducting wire and around a distribution line, through laboratory experiments. Our results indicate that both methods provide an effective means of detecting distribution-line deterioration.

Summary form only given. An important problem in the electric power industry is the deterioration of distribution lines. We have proposed a nondestructive detection system for the deterioration in a distribution line by measuring the magnetic field around the distribution line when it is live. We examine the distribution of the magnetic field around a line using a search coil in a laboratory experiment.

To improve the bit error rate (BER) with a low outband emission, we propose an OFDM system with modified predistorter and maximum likelihood sequences (MLS). In the proposed system, input data are mapped to signal point series over multiple subcarriers. Then, the peak power is reduced with the partial transmit sequence (PTS) technique. After limited to the saturation amplitude of the high-power-amplifier (HPA), the signal is applied to the predistorter. Compared with the system using the conventional predistorter, the compression quantity of signal in the proposed system is small, because the peak power is reduced with the PTS technique beforehand. In addition, the minimum Euclidean distance in the proposed system is larger than that of the conventional system. Thus, the proposed system can improve the BER with the low outband emission. We show that only the proposed system can achieve the good performance in terms of both the BER and power spectrum density (PSD).

This paper describes a real-time hierarchical system that fuses data from vision and touch sensors to improve the performance of a coordinate measuring machine (CMM) used for dimensional inspection tasks. The system consists of sensory processing, world modeling, and task decomposition modules. It uses the strengths of each sensor -- the precision of the CMM scales and the analog touch probe and the global information provided by the low resolution camera -- to improve the speed and flexibility of the inspection task. In the experiment described, the vision module performs all computations in image coordinate space. The part's boundaries are extracted during an initialization process and then the probe's position is continuously updated as it scans and measures the part surface. The system fuses the estimated probe velocity and distance to the part boundary in image coordinates with the estimated velocity and probe position provided by the CMM controller. The fused information provides feedback to the monitor controller as it guides the touch probe to scan the part. We also discuss integrating information from the vision system and the probe to autonomously collect data for 2-D to 3-D calibration, and work to register computer aided design (CAD) models with images of parts in the workplace.

Alcohol acutely causes vasodilation and hypotension in Orientals. To study the mechanisms responsible for the alcohol-induced blood pressure (BP) reduction, we examined levels of various vasoactive hormones after a single intake of alcohol in twelve Japanese men with mild hypertension. On the alcohol intake day, they consumed 1 ml/kg of alcohol with an evening meal, while on the control day they took an isocaloric control drink. BP and vasoactive hormone levels were determined before and 2 h after intake of the alcohol or the control drink. BP after alcohol ingestion was significantly lower than that before drinking or on the control day. This alcohol-induced hypotension was associated with significant increases in heart rate, plasma catecholamines and plasma renin activity (PRA). The changes in heart rate and plasma noradrenaline were inversely related to the changes in BP. Plasma levels of vasopressin and insulin were lower in the alcohol period than in the control period, but these changes were not correlated with the changes in BP. Levels of aldosterone, cortisol, atrial natriuretic peptide, prostaglandin (PG) E2, 6-keto-PGF1 alpha, beta-endorphin, and cyclic GMP were not significantly different between the alcohol and the control periods. These results suggest that changes in pressor hormones may not contribute to the acute hypotensive effect of alcohol, and that the sympathetic nervous system is activated by the BP reduction. The levels of the depressor hormones measured also appear to play no role in alcohol-induced hypotension.

OBJECTIVE--To investigate the relation between plasma concentrations of immunoreactive endothelin and haemodynamic variables before and after percutaneous transvenous balloon dilatation of the mitral valve. DESIGN--Prospective study. SETTING--National cardiovascular centre. PATIENTS--25 patients with mitral stenosis and 26 healthy volunteers. MAIN OUTCOME MEASURES--Plasma concentrations of immunoreactive endothelin were measured in the pulmonary artery, left atrium, ascending aorta, and femoral vein before and after balloon dilatation of the mitral valve. RESULTS--Peripheral venous concentrations (mean (SD)) of endothelin were higher in the patients with mitral stenosis than in the healthy volunteers (1.76 (0.51) v 1.37 (0.45) pg/ml, p < 0.05) and they correlated with the mean left atrial pressure (r = 0.74, p < 0.01). Balloon dilatation of the mitral valve reduced the mean left atrial pressure without changing the mean right atrial pressure, systemic arterial pressure, heart rate, or cardiac index. Concentrations of plasma endothelin in the femoral vein increased from 1.76 (0.51) to 3.39 (2.46) (p < 0.01), 4.82 (2.34) (p < 0.001), and 2.43 (0.52) pg/ml (p < 0.05) at 15 and 30 minutes and 24 hours after the procedure. The concentration of endothelin in the pulmonary artery also increased from 1.85 (0.85) to 4.32 (1.58) pg/ml (p < 0.01) 30 minutes after the dilatation, whereas there were no appreciable changes in endothelin concentration in the left atrium or ascending aorta. CONCLUSIONS--Plasma endothelin concentrations were higher in patients with mitral stenosis than in healthy volunteers and the increase was proportional to left atrial pressure. After balloon dilatation of the mitral valve there was an abrupt rise in endothelin in the femoral vein and pulmonary artery but no change in left atrial or aortic blood samples. These findings suggest that endothelin may be another vasoactive substance involved in congestive heart failure.

The effect of manidipine, a new Ca2+ antagonist, on intrarenal hemodynamics was assessed in essential hypertension and compared with nicardipine, a previously studied Ca2+ antagonist. Identical 2-week studies were repeated before and during the administration of manidipine (10 mg once daily, 2 weeks) in 3 patients with essential hypertension who were given regular- and sodium-restricted diets for 1 week each. The renal function curve (pressure-natriuresis relationship) was drawn by plotting the urinary sodium excretion rate on the y-axis as a function of the systemic mean arterial pressure (MAP) on the x-axis. Assuming that the difference between MAP and the extrapolated x-intercept of the renal function curve represents the effective filtration pressure across the glomerular capillary walls, the intrarenal hemodynamics were calculated (e.g., afferent arteriolar resistance (RA), efferent arteriolar resistance (RE), and glomerular pressure (PG)). During the regular sodium diet, MAP was lowered from 100 +/- 7 to 93 +/- 5 mmHg (p0.04) and the effective filtration pressure was lowered from 20 +/- 2 to 10 +/- 3 mmHg (p0.05); the renal plasma flow rate (pre: 560 +/- 74 vs. post: 627 +/- 108 mL/min) and glomerular filtration rate (82 +/- 10 vs. 78 +/- 5 mL/min) were not altered. RA remained unchanged (3,800 +/- 700 vs. 3,400 +/- 300 dyn.sec.cm-5; % reduction: 4 +/- 16%) whereas RE was reduced from 4,300 +/- 700 to 3,300 +/- 800 dyn.sec.cm-5 (19 +/- 15%). Thus, PG was lowered from 58 +/- 2 to 50 +/- 2 mmHg (13 +/- 3%), which parallels with the reduction in MAP.(ABSTRACT TRUNCATED AT 250 WORDS)

Renal effects of endothelin-1 (ET-1, human, 1-21) and the equivalent molar concentration of big ET (human, 1-38) and the contributions of prostaglandins and endothelium-derived relaxing factor to these actions were examined. Intrarenal infusion of ET-1, at a dose of 0.4 pmol/kg/min, decreased renal blood flow (RBF), glomerular filtration rate (GFR), and urine output (V) to 62, 70, and 45% of control values, respectively. Additional aspirin-DL-lysine (ASP) treatment (25 mg/kg) caused marked decreases in RBF, GFR, and V to 20, 14, and 9% of control values, respectively. During ET-1 infusion, intrarenal infusion of NG-monomethyl-L-arginine (L-NMMA, 1 mumol/min) caused decreases in RBF, GFR, and V. In another group, intrarenal infusion of big ET at a dose equivalent to that of ET-1 did not significantly affect RBF, GFR, or urine output, which were 95, 107, and 84% of control values, respectively. Additional ASP treatment decreased these values to 78, 69, and 52% of control values, respectively. L-NMMA infusion during big ET infusion showed little effect on renal function. Our study demonstrated that intrarenal infusion of ET-1, at a dose of 0.4 pmol/kg/min, caused significant hemodynamic and functional changes in the canine kidney compared with an equivalent molar concentration of big ET.

The differences between sodium sensitive and sodium retaining hypertension were theoretically considered using a water tank model of body fluid volume-blood pressure regulation. If an outlet valve is attached to a tank with a base area corresponding to the reciprocal of total peripheral resistance (TPR) and water is poured into this tank at a rate corresponding to the amount of Na+ intake, then equilibrium should be achieved at a certain water level, volume and output from the outlet, which represent mean arterial pressure (MAP), cardiac output (CO) and urinary Na+ excretion. The height of the outlet from the tank bottom and the size cross-sectional area, of the outlet correspond to the x-intercept and slope of the renal function (pressure-natriuresis) curve, respectively. In both nonsodium sensitive hypertension, due to the shift of the curve toward a higher blood pressure level (elevated height of the outlet) without change in the slope (size of the outlet), and sodium sensitive hypertension, due to the depressed slope of the curve (reduced outlet size), not only MAP (water level) but also CO (water volume) are increased, resulting in sodium retaining hypertension, if TPR (reciprocal of base area) remained unchanged, while CO is relatively unchanged, resulting in nonsodium retaining hypertension, if TPR is elevated. Thus, the MAP and its sensitivity to sodium intake is determined by the renal function curve. Since body fluid volume is determined by both the renal function curve and TPR, however, changes in TPR during the development of hypertension is a major factor in determining whether or not the body fluid volume has to change only a small amount or a large amount. Therefore, the sodium sensitivity of blood pressure and sodium retention must be considered separately.

We have compared hypertensive target organ damage with home blood pressure readings (HBPs) and with office blood pressure readings (OBPs) in 100 patients with mild to moderate essential hypertension. The correlation between blood pressure levels and hypertensive target organ damage in HBPs and OBPs were similar (r = .42, p less than 0.001 for systolic HBPs; r = .33, p less than 0.001 for diastolic HBPs; r = .42, p less than 0.001 for systolic OBPs; r = .34, p less than 0.001 for diastolic OBPs). In most instances, HBPs were lower than corresponding OBPs. Among individual patients whose OBPs were identical, HBPs in some instances differed strikingly. Optic fundi abnormalities were significantly more severe in patients whose systolic HBPs were 150 mmHg or greater, than in those whose systolic HBPs were less than 150 mmHg (p less than 0.05). Hypertensive complications did not differ among office hypertensive patients who were normotensive or borderline hypertensive at home, from the differences of OBPs. We concluded that overall hypertensive complications were equally related to HBPs and OBPs, but patients with discrepancies between HBPs and OBPs had fewer hypertensive complications. Thus, both OBPs and HBPs should be considered in deciding therapy.

Adenylate cyclase responses to pituitary hormones including adrenocorticotropic hormone (ACTH), biogenetic amines, prostaglandin E1 (PGE1), angiotensin II, and glucagon were evaluated in adrenocortical tumors and hyperplastic adrenal tissues, obtained from patients with Cushing's syndrome at surgery, and in normal adrenals. The adenylate cyclase of two normal adrenals was activated only by ACTH and PGE1 among the hormones tested, while that of two hyperplastic adrenal tissues due to excessive pituitary ACTH secretion was stimulated only by ACTH. Of five ACTH-responsive adrenocortical adenomas, in contrast, three were stimulated by norepinephrine, two by epinephrine, one by thyroid-stimulating hormone, and one by luteinizing hormone in addition to ACTH, indicating the presence of multiple receptors for hormones other than ACTH and PGE1 in these four tumors. The cyclase of an ACTH-unresponsive adrenocortical carcinoma ws activated only by PGE1 and not by other hormones including ACTH, whereas that of an ACTH-responsive adrenocortical nodular hyperplasia was stimulated by ACTH and glucagon but not by other hormones including PGE1. These results indicate the presence of multiple receptors for hormones other than ACTH and PGE1, the normal adrenocortical stimulants, in human adrenocortical tumors, particularly in adrenal adenomas, but not in normal and hyperplastic (of whichever an etiology) adrenocortical tissues, suggesting a functional alteration of the cellular membrane receptors in human adrenocortical tumors.