Showing papers by "Tohoku University published in 1979"

Horizontal symmetry and masses of neutrinos

Abstract: Assuming a horizontal symmetry SU_F(n), we demonstrate a possibility that the left-handed neutrinos receive masses of order 1eV, which is consistent with recent experiments on neutrino oscillations. The smallness of the neutrino masses is an indication of a large breaking of the horizontal symmetry.

Comparison of the antimanic efficacy of carbamazepine and chlorpromazine: A double-blind controlled study

Abstract: A multiinstitutional cooperative study comparing carbamazepine (Tegretol) with chlorpromazine was performed using a controlled, double-blind trial design. In a series of 63 cases of endogenous manic psychosis, carbamazepine's clinical utility and efficacy, characteristics of therapeutic effect, and side effects were evaluated. Carbamazepine and chlorpromazine were given by a fixed, but flexible, method at an equipotent ratio of 2∶1, starting from the initial dosages of 300 and 150 mg, respectively. The overall improvement rate, based on the number of cases showing moderate to marked amelioration of manic symptoms, was 70% in the carbamazepine group and 60% in the chlorpromazine group. No significant differences were found between the two groups. Improvements in basic mood, insomnia, headache and lassitude, and diurnal fluctuations of mood tended to be characteristic of carbamazepine efficacy for mania compared with the effects of chlorpromazine. The onset of therapeutic effect was within 10 days of treatment in 65.7% of the patients receiving carbamazepine and 50% receiving chlorpromazine. The incidence of side effects was significantly lower in the carbamazepine group than in the chlorpromazine group. It was suggested that carbamazepine is potentially useful drug for the treatment of the manic state.

The role of glucocorticoid receptor and gene expression in the anti-inflammatory action of dexamethasone.

Abstract: GLUCOCORTICOIDS are potent anti-inflammatory agents, but the molecular mechanisms involved in this activity are not yet understood. The biological actions of various steroid hormones have been shown to be mediated by functional proteins synthesised following translocation of a hormone-cytoplasmic receptor complex into the nucleus1,2. It is still not clear, however, whether the anti-inflammatory effects of glucocorticoids are mediate via binding to a cytoplasmic receptor in target cells and subsequent activation of gene expression3, although glucocorticoid receptors have been demonstrated in HTC cells, liver5, thymocytes6 and lymphocytes7. The results reported here suggest that a glucocorticoid receptor and the induction of gene expression are involved in the anti-inflammatory action of dexamethasone.

Some problems on the histopathological diagnosis of non-Hodgkin's malignant lymphoma -- a proposal of a new type.

Abstract: A new classification for non-Hodgkin's malignant lymphoma is proposed as the one suited for the Lymphomas in Japan, which is to provide a new subtype "pleomorphic" for those more or less rapid-growing lymphomas of peripheral T-cell nature, along with another subtype lymphoblastic, after Nathwani et al. for those of central T-cell nature. The proposal is based on the result of the investigation by the Study Group for Histopathological Diagnosis on Malignant Lymphoma that (1) the presence of a significant number of T-cell lymphomas with peculiar "pleomorphism" is responsible for the very low reproducibility rate of histopathological diagnosis on the diffuse, mixed L&H type of Rappaport classification, and (2) the relative incidence of lymphoms as peripheral T-cell nature including the so-called adult T-cell leukemia is much higher in Japan than in the Western countries.

Perpendicular magnetic recording with a composite anisotropy film

Abstract: For a recently proposed perpendicular recording system, a composite anisotropy medium has been developed to improve the recording sensitivity of the perpendicular recording head. The medium is composed of a Fe-Ni soft magnetic film and a Co-Cr perpendicular anisotropy film, which are successively deposited on a base by an r. f. sputtering. By using the new double layer medium, an extremely high recording sensitivity could be obtained, compared with the single layer Co-Cr medium. The recording current needed to saturate the double layer film decreased to one-tenth of that for the single layer Co-Cr film. Although the Fe-Ni layer was soft magnetic material, neither deterioration of the frequency response nor peak shift was observed for the double layer film. The reproduction with a perpendicular head was also investigated, and a high output voltage and a high signal-to-noise ratio were obtained.

On Fermat varieties

Abstract: (0.1) x? + x? + + x?+ί = 0 . Throughout this paper, we denote it by Xrm, or by X r m(p), when we need to specify the characteristic p of the base field k; we always assume that m ^ 0 (mod p). The purpose of this paper is to clarify the "inductive structure" of Fermat varieties of a common degree and of various dimensions, and apply it to the questions concerning the unirationality and algebraic cycles of a Fermat variety. The main results are stated as follows: THEOREM I. For any positive integers r and s, XZf is obtained from the product Xrm x X 8 m by 1) blowing up a subvariety isomorphic to X~ x X'*, 2) taking the quotient of the blown up variety with respect to an action of the cyclic group of order m, and 3) blowing down from the quotient two subvarieties isomorphic to P x X'ΰ and Xlr x P\

ISFET's using inorganic gate thin films

Abstract: The characteristics of various types of ISFET's using inorganic gate films are described. The pH and pNa selectivities are investigated for SiO 2 , Si 3 N 4 , Al 2 O 3 , alumino-silicate, and sodium-aluminosilicate gate dielectrics. The transient response and device stability are also studied for different values of solution pH. The Al 2 O 3 gate shows a nearly ideal pH response, excellent stability, and selectivity to other cations. On the other hand, the Si 3 N 4 gate is also a good pH sensor, but it is proved by the studies of SiO 2 and SiO x N y films that the oxygen content in its surface degrades its properties as a pH sensor. Sodium-alumino-silicate, which is generally known as a material for pNa selective glass electrodes, is utilized as a gate film for the pNa ISFET. The pNa selectivity of this device is comparable to that of the conventional glass electrode. The alumino-silicate gate has also a pNa selectivity, but it is inferior to the sodium-alumino-silicate gate.

Differential volumetry of A, B and D cells in the pancreatic islets of diabetic and nondiabetic subjects.

Abstract: The percentile volumes vA, vB and vD of A, B and D cells in the islets of Langerhans were histometrically estimated in the pancreases from 59 autopsy cases including maturity- and growth-onset diabetics and nondiabetics. Volumetry was performed microscopically by point counting method using a square-lattice eyepiece, then the total A, B and D cell volumes VA, VB, and VD were calculated from the total islet volume Vi of the pancreas in VB between the three groups. Namely, it was only 0.156 and 0.388 cm3 in the growth- and maturity-onset diabetics, much smaller values than 0.636 cm3 in nondiabetics. The simultaneous investigation on clinical records revealed a negative correlation between VB and the maximum blood sugar of the individual. The smaller VB in diabetes was attributed to the diminution of Vi because vA, vB and vD were almost the same regardless of the presence or absence of diabetes. These results strongly suggested a failure of insulin production in diabetes due to quantitative deficiency of B cells.

Pulse spreading in a single-mode fiber due to third-order dispersion

Abstract: Pulse spreading in a single-mode optical fiber is discussed taking into account the third-order dispersion term of the waveguide when the light source is modulated by a Gaussian pulse. A general expression for the pulse shape is analytically obtained, and an asymptotic approximation is used when the third-order dispersion term is small. It is also shown that the pulse width is no longer proportional to the guide length when the third-order dispersion term becomes large.

Observations of Solitary Structures in a Magnetized, Plasma Loaded Waveguide

Abstract: Two types of solitary structure were investigated experimentally and numerically in a magnetized, plasma-loaded waveguide. One was identified as an ordinary KdV soliton and its properties were investigated with particular attention to the damping by resonant particles. The other type of pulse was identified as a purely kinetic phenomenon being associated with a vortex in phase space.

Pharmacological profile of a new coronary vasodilator drug, 2-nicotinamidoethyl nitrate (SG-75).

Abstract: Summary 1. In anaesthetized, open-chest dogs, 2-nicotinamidoethyl nitrate (SG-75) administered intravenously (0.3–1 mg/kg) or intraduodenally (3 mg/kg) produced decreases in systemic blood pressure, coronary resistance, heart rate and an increase in coronary sinus outflow, but virtually no change in myocardial oxygen consumption and atrioventricular conduction. The effects of SG-75 administered intraduodenally emerged within a few minutes after dosing and lasted over about 1 h. 2. In isolated, blood-perfused sino-atrial node preparations of the dog SG-75 administered into the sinus node artery decreased slightly sinus rate at the dose which doubled blood flow through the artery. 3. In isolated, blood-perfused atrioventricular node preparations of the dog SG-75 administered into the atrioventricular node artery did not impair atrioventricular conduction even in doses which increased blood flow through the artery to more than twice the basal level. 4. In isolated, blood-perfused papillary muscle preparations of the dog SG-75 administered into the anterior septal artery scarcely affected force of contraction of the papillary muscle at the dose which doubled blood flow through the artery, although in further large doses it produced a transient decrease in the force of contraction. In extremely large doses it produced ventricular fibrillation. 5. In anaesthetized, open-chest dogs in which cardiac input was kept constant SG-75 (0.01–1 mg/kg) administered into the ascending aorta increased venous return without changing systemic output. 6. 2-Nicotinamidoethyl alcohol, a denitrated compound of SG-75, had no vasodilator action in doses comparable to those of the parent compound. 7. These results indicate SG-75 to be a potential antianginal drug having no cardiodepressant actions but having properties uncharacteristic of the nitrates.

Role of Norwalk virus in outbreaks of nonbacterial gastroenteritis.

Abstract: Twenty-five separate outbreaks of nonbacterial gastrointestinal illnesses were studied serologically for evidence of infection with the Norwalk virus and the rotaviruses that affect humans. Eight of 25 outbreaks appeared to be related to the Norwalk virus. In one of the 25 outbreaks, there was evidence of rotavirus infection. These observations suggest that the Norwalk virus or serologically related agents play an important role in epidemic nonbacterial gastroenteritis in adults and older children.

Buneman Instability, Pierce Instability, and Double-Layer Formation in a Collisionless Plasma

Abstract: Instabilities and double-layer formation are systematically investigated on a bounded collisionless system with electron beam penetrating through a plasma. The Buneman instability is observed at low beam currents. Above a critical current, there appears a sudden nonoscillatory potential drop due to the Pierce instability, which traps ions in the potential well. This collisionless ion trapping provides a new formation mechanism of the double layer, which is controlled by changing the speed of the potential drop.

Anomalous characteristics of the microcrystalline state of SiC fibres

Abstract: FIBRES of SiC are prepared1–4 from the polycarbosilane which, in various forms, is made into a precursor by melt-spinning: the precursor is then heated to produce the SiC fibre. Ceramics are produced in this way by heating the organosilicon polymer. The organic precursor is prepared in a subtle form (for example, as fibres) which is extremely difficult to produce from an inorganic precursor. On heating the organic precursor a ceramic skeleton remains. This inorganic residue derived from an organosilicon polymer possesses characteristics not previously known and these are reported here.