Orbital Magnetism in Confined Two-Dimensional Systems

The way how the Landau diamagnetism emerges in finite two-dimensional systems, disc and ring, has been clarified by examining both the field dependences of the magnetization and the spatial distribution of the persistent currents induced by the magnetic field.     

Theory for Slightly Doped Antiferromagnetic Mott Insulators

Trial wavefunctions, constructed explicitly from the unique 2-dimensional Mott insulating state with antiferromagnetic order, are proposed to describe the low-energy states of a Mott insulator slightly doped with holes or electrons. With the state behaving like charged quasi-particles with well-defined momenta, a rigid band is observed. These states have much less pairing correlations than previously studied ones. Small Fermi patches obtained are consistent with recent experiments on high T _c cuprates doped lightly with holes or electrons. States showing the incoherent and spin-bag behaviors are also discussed. Using these wavefunctions, a number of results obtained by exact calculations are reproduced.     

Cavernous hemangioma of the scrotum: a case report

A 19-year-old male consulted our department, complaining of a painful scrotal mass. On palpation, the mass was discriminated from testis, epididymis, and spermatic cord in the left scrotum. He underwent total excision of the mass. Pathologic examination revealed cavernous hemangioma. Scrotal hemangioma is a relatively rare lesion and this is the 37th case reported in Japan.     

Peroxynitrite formation in focal cerebral ischemia-reperfusion in rats occurs predominantly in the peri-infarct region

The plasma pharmacokinetics of danofloxacin administered at 1.25 mg kg-1 body weight by the intravenous and intramuscular routes were determined in sheep. Tissue distribution was also determined following administration by the intramuscular route at 1.25 mg kg-1 body weight. Danofloxacin had a large volume of distribution at steady state (Vdss) of 2.76 +/- 0.16 h (mean +/- S.E.M.) L kg-1, an elimination half-life (t1/2 beta) of 3.35 +/- 0.23 h, and a body clearance (C1) of 0.63 +/- 0.04 L kg-1 h-1. Following intramuscular administration it achieved a maximum concentration (Cmax) of 0.32 +/- 0.02 microgram mL-1 at 1.23 +/- 0.34 h (tmax) and had a mean residence time (MRT) of 5.45 +/- 0.19 h. Danofloxacin had an absolute bioavailability (F) of 95.71 +/- 4.41% and a mean absorption time (MAT) of 0.81 +/- 0.20 h following intramuscular administration. Mean plasma concentrations of > 0.06 microgram mL-1 were maintained for more than 8 h following intravenous and intramuscular administration. Following intramuscular administration highest concentrations were measured in plasma (0.43 +/- 0.04 microgram mL-1), lung (1.51 +/- 0.18 micrograms g-1), and interdigital skin (0.64 +/- 0.18 microgram g-1) at 1 h, duodenal contents (0.81 +/- 0.40 microgram mL-1), lymph nodes (4.61 +/- 0.35 micrograms g-1), and brain (0.06 +/- 0.00 microgram mL-1) at 2 h, jejunal (10.50 +/- 4.31 micrograms mL-1) and ileal (5.25 +/- 1.67 micrograms mL-1) contents at 4 h, and colonic contents (8.94 +/- 0.65 micrograms mL-1) at 8 h.     

Application of parallel genetic algorithms to generation expansion planning using parallel processors

This paper presents an application of parallel genetic algorithms (PGA) to the optimal long-range generation expansion planning. The problem can be formulated as a combinatorial optimization problem that determines the order of introduced generation units at each interval of the year. The proposed method considers introduced power limits of each technology, maximum loads at each interval, and load duration curves at each interval. Appropriate string representation for the problem is presented. Binary and decimal coding and three selection methods are compared. The method is developed on a transputer that is one of the parallel processors. The feasibility of the proposed method is demonstrated using a typical expansion problem with four technologies and five intervals. The method is then compared with conventional dynamic programming and a simple genetic algorithm with promising results.     

Optimal planned maintenance with salvage cost for a two-unit standby redundant system

This paper considers the optimal spare ordering policies for a cold standby redundant system with two dissimilar units. Especially, the planned maintenance schedule with salvage cost is discussed. The failure time distributions for respective units are assumed to be arbitrary. By applying the expected cost per unit time in the steady-state and the stationary availability as criteria of optimality, the optimal ordering policy minimizing or maximizing each criterion is obtained under some economical and/or physical assumptions. Finally, numerical examples are presented, and the effect of the failure time distributions for the optimal ordering policy is examined in detail.     

Normal spectral emissivities of liquid Ag-Cu alloys in the visible and infrared regions

The wavelength and composition dependencies of normal spectral emissivities for liquid Ag-Cu alloys have been measured over a wavelength range between 450 and 1500 nm at temperatures from 1273 to 1423 K in a cold crucible furnace. The spectral emissivities abruptly increase in the visible region with decreasing wavelength. The wavelength at the abrupt increase in the emissivity shifts to a shorter wavelength as the concentration of silver in the alloy increases. This suggests that the abrupt increases are attributed to the direct interband transition, and the energy gap between the d band and the Fermi level increases with an increase in silver concentration in the alloy. To the contrary, the spectral emissivities in the infrared region were found to exhibit weak negative wavelength dependencies, which are attributed to the intraband transition. The composition dependencies of spectral emissivities observed in the infrared region have been explained by the Drude model.     

Atrophy of the corpus callosum associated with cognitive impairment and widespread cortical hypometabolism in carotid artery occlusive disease

BACKGROUND: The independent influences of small-intestinal bacterial overgrowth and old age on mucosal immunoglobulin production and secretion have not been assessed. This is an important issue, since luminal IgA deficiency may exacerbate small-intestinal bacterial overgrowth, the prevalence of which is high in selected elderly populations. METHODS: Proximal small-intestinal aspirates were obtained from 33 subjects for bacteriologic analysis and measurement of total IgA, IgM, total IgG. IgG subclass, and IgD concentrations. IgA subclasses were measured in 24 unselected subjects. Serum immunoglobulin and salivary IgA concentrations were measured in all subjects. RESULTS: IgA2 and IgG3 were predominant IgA and IgG subclasses in proximal small-intestinal luminal secretions. Luminal concentrations of IgA2 and IgM, but not IgG3 or any other IgG subclass, were significantly increased in small-intestinal bacterial overgrowth, which was present in 19 of 33 (57.6%) subjects. Old age did not influence these levels. Luminal immunoglobulin concentrations did not correlate significantly with either serum or salivary values. IgD was not measureable in proximal small-intestinal secretions. CONCLUSIONS: Increased luminal concentrations of the secretory immunoglobulins, IgA2 and IgM, occur in small-intestinal bacterial overgrowth. Local investigation is mandatory when assessing the mucosal immunopathology of this disorder. Luminal IgG3 is unlikely to be predominantly derived from serum. Old age does not independently influence luminal immunity.