Statistical properties of spectral fluctuations for a quantum system with infinitely many components.

Extending the idea formulated in Makino [Phys. Rev. E 67, 066205 (2003)], that is based on the Berry-Robnik approach [M. V. Berry and M. Robnik, J. Phys. A 17, 2413 (1984)], we investigate the statistical properties of a two-point spectral correlation for a classically integrable quantum system. The eigenenergy sequence of this system is regarded as a superposition of infinitely many independent components in the semiclassical limit. We derive the level number variance (LNV) in the limit of infinitely many components and discuss its deviations from Poisson statistics. The slope of the limiting LNV is found to be larger than that of Poisson statistics when the individual components have a certain accumulation. This property agrees with the result from the semiclassical periodic-orbit theory that is applied to a system with degenerate torus actions [D. Biswas, M. Azam, and S. V. Lawande, Phys. Rev. A 43, 5694 (1991)].

Level spacing statistics of classically integrable systems: investigation along the lines of the Berry-Robnik approach.

By extending the approach of Berry and Robnik, the limiting level spacing distribution of a system consisting of infinitely many independent components is investigated. The limiting level spacing distribution is characterized by a single monotonically increasing function mu(S) of the level spacing S. Three cases are distinguished: (1) Poissonian if mu(+ infinity)=0, (2) Poissonian for large S, but possibly not for small S if 0

Liouvillian dynamics of the Hopf bifurcation.

Two-dimensional vector fields undergoing a Hopf bifurcation are studied in a Liouville-equation approach. The Liouville equation rules the time evolution of statistical ensembles of trajectories issued from random initial conditions, but evolving under the deterministic dynamics. The time evolution of the probability densities of such statistical ensembles can be decomposed in terms of the spectrum of the resonances (i.e., the relaxation rates) of the Liouvillian operator or the related Frobenius-Perron operator. The spectral decomposition of the Liouvillian operator is explicitly constructed before, at, and after the Hopf bifurcation. Because of the emergence of time oscillations near the Hopf bifurcation, the resonance spectrum turns out to be complex and defined by both relaxation rates and oscillation frequencies. The resonance spectrum is discrete far from the bifurcation and becomes continuous at the bifurcation. This continuous spectrum is caused by the critical slowing down of the oscillations occurring at the Hopf bifurcation and it leads to power-law relaxation as 1/square root of [t] of the probability densities and statistical averages at long times t-->infinity. Moreover, degeneracy in the resonance spectrum is shown to yield a Jordan-block structure in the spectral decomposition.

Psychoeducation for the families of patients with eating disorders and changes in expressed emotion: A preliminary study.

Psychosocial variables such as expressed emotion (EE) have prognostic significance, and family psychoeducation has been developed to aid in the treatment of various psychiatric disorders. This study reports relationships among EE, family factors, and symptoms observed while conducting multifamily psychoeducation for eating disorders. Group sessions were held once a month for the relatives of patients with DSM-IV eating disorders, and the group met for five sessions that included both education and problem-solving. Thirty-seven relatives volunteered to participate in our program, and of these, 28 completed the program. EE (as measured by the Five-Minute Speech Sample [FMSS]), family function (as measured by the Family Adaptability and Cohesion Evaluation Scales [FACES]), the family's mental state (as measured by the Profile of Mood States [POMS]), and patient's symptoms (as measured by the Eating Disorder Evaluation Scales [EDES] and Global Assessment of Functioning [GAF] on clinician evaluations, and by the Anorexic Behavior Observation Scale [ABOS] assessment of the family) were administered at both the first and final sessions. The rates of high-EE relatives tended to decrease (especially high emotional overinvolvement [EOI]), and families' assessment of symptoms was also significantly improved. Twice-repeated multivariate analysis of variance (MANCOVA) showed that EOI, ABOS, and POMS scores were changed significantly during the sessions. Psychoeducation for the family members of patients with eating disorders might help lower distress and encourage positive interactions within the family. EE is an important measure in evaluations of psychoeducation. However, a randomized, controlled trial is needed to clarify the efficacy of this treatment.

An analytical construction of the SRB measures for Baker-type maps.

For a class of dynamical systems, called the axiom-A systems, Sinai, Ruelle and Bowen showed the existence of an invariant measure (SRB measure) weakly attracting the temporal average of any initial distribution that is absolutely continuous with respect to the Lebesgue measure. Recently, the SRB measures were found to be related to the nonequilibrium stationary state distribution functions for thermostated or open systems. Inspite of the importance of these SRB measures, it is difficult to handle them analytically because they are often singular functions. In this article, for three kinds of Baker-type maps, the SRB measures are analytically constructed with the aid of a functional equation, which was proposed by de Rham in order to deal with a class of singular functions. We first briefly review the properties of singular functions including those of de Rham. Then, the Baker-type maps are described, one of which is nonconservative but time reversible, the second has a Cantor-like invariant set, and the third is a model of a simple chemical reaction R<-->I<-->P. For the second example, the cases with and without escape are considered. For the last example, we consider the reaction processes in a closed system and in an open system under a flux boundary condition. In all cases, we show that the evolution equation of the distribution functions partially integrated over the unstable direction is very similar to de Rham's functional equation and, employing this analogy, we explicitly construct the SRB measures. (c) 1998 American Institute of Physics.

Release of active and inactive renin by the human kidney.

1. Active and inactive renin were assayed in plasma of the renal veins and the inferior vena cava below the kidney in eight patients with hypertension and unilateral renal abnormalities, 20 min after the patients had resumed the upright position. 2. The concentration of active renin on the affected side was significantly higher than that on the non-affected side. The concentration of inactive renin on the affected side was significantly lower than that on the non-affected side and in the inferior vena cava. 3. These findings suggest either that the affected kidney mainly secretes active renin, which is then converted into inactive renin in the extrarenal circulation, or that the affected kidney activates inactive renin.

Primary aldosteronism aggravated during peripartum period.

Two cases are reported of a 30-year-old and of a 28-year-old Japanese women with primary aldosteronism in whom metabolic and blood pressure abnormalities were aggravated during peripartum period. The characteristic findings in 2 present cases are as follows; 1) lower blood pressure during pregnancy, 2) elevated blood pressure during peripartum period, and 3) after parturition, serum potassium decreased, and the blood pressure elevated. The reason why the hypertension and hypokalemia associated with primary aldosteronism were ameliorated during pregnancy was thought to be due to the increased secretion of progesterone. Furthermore, the rapid recurrence of symptoms, increase in blood pressure, and hypokalemia in the post-partum period could be related to elevated prolactin and decreased progesterone levels.