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The PKC1 gene of the budding yeast Saccharomyces cerevisiae encodes a homolog of the alpha, beta, and gamma isoforms of mammalian PKC that is essential for cell growth. Loss of PKC1 function results in a cell lysis defect that is suppressed by osmotic stabilizing agents, suggesting a defect in cell wall integrity. In this study, we show that Pkc1p-depleted cells develop holes in their cell walls positioned at their bud tips, the site to which growth is focused during polarized cell growth. This result suggests that pkc1 mutants are deficient in the process of cell wall remodeling during growth. In further support of this model, cells bearing a pkc1 delta mutation, allowed to proliferate in the presence of osmotic stabilizing agents, possessed cell walls that were only 60% as thick as wild-type cell walls. This diminution in cell wall material affected both the beta-glucan layer and the mannoprotein layer. We have exploited the cell lysis defect of pkc1 mutants to identify genes that function within the same signalling pathway at points downstream of PKC1. These genes comprise a protein kinase cascade that culminates in the activation of the MAP kinase homolog Mpk1p. The proposed order of protein kinase function, based on genetic experiments, is Pkc1p to Bck1p to Mkk1/2p to Mpk1p. Consistent with the proposed model, Pkc1p selectively phosphorylates Bck1p in vitro and Mpk1p protein kinase activity requires a functional BCK1 gene.

Revascularization of the spinal arteries with thoracic aortic aneurysm were performed on nineteen patients using partial extracorporeal bypass. They were 16 men and 3 women. Age range were from 33 to 70 years (mean 49.9 +/- 10.3 years). There were eleven patients of dissecting aneurysm (DeBakey type IIIb in eight patients, type I in two patients and type IIIa in one patient), and eight patients of non-dissecting thoracoabdominal aneurysm (including two patients with ruptured aneurysm). The number of revascularized spinal arteries were 60 pairs (average 3.2 pairs per each patient). The revascularized spinal arteries were localized between levels T4 and L5.36 pairs of the 60 existed between levels T8 and L2 from where the artery of Adamkiewicz arises. Seven patients (eleven spinal arteries) underwent selective angiography of the revascularized spinal arteries postoperatively, and the anterior spinal artery and the artery of Adamkiewicz was identified in three patients. Two patients died within one month, one from MOF and the another from intestinal perforation respectively (operative mortality 11.1%). One patient, with ruptured thoracoabdominal aortic aneurysm showed paraparesis postoperatively, but no paraplegia was found in any patients. We recommend that not only the artery of Adamkiewicz but also the spinal arteries at the midthoracic area from T4 to T8 should be revascularized, to prevent postoperative paraplegia. Replacing of extended thoracic aneurysm, our method (using partial extracorporeal circulation and segmental aortic clamping) was thought to prevent spinal cord ischemia.

Glycoproteins which bound to Dolichos biflorus agglutinin (DBA) were isolated from the small intestine of 129/Sv mice. Among oligosaccharides released from the carbohydrate moieties of the glycoproteins by endo-beta-galactosidase, the major one with N-acetylgalactosamine at the non-reducing end was isolated by QAE-Sephadex A-25 column chromatography. The structure of the oligosaccharide was elucidated to be GalNAc beta 1----4(NeuAc alpha 2----3)Gal beta 1----4GlcNAc beta 1----3Gal by compositional analysis, methylation analysis before and after mild acid hydrolysis, sequential glycosidase digestion, secondary ion mass spectrometry (SIMS), and nuclear magnetic resonance spectroscopy. The SIMS signal of m/z 1,071 was consistent with the presence of the branched sequence, GalNAc(NeuAc)GalGlcNAc, and the signal was also detected in the high-molecular-weight fraction obtained after endo-beta-galactosidase digestion. The pentasaccharide identified here has the terminal structure of ganglioside GM2, and an apparently identical one has been identified as the epitope of blood group Sda and the DBA binding site in human T-H urinary glycoprotein. Thus, the present result has extended our knowledge of the biological meaning of the oligosaccharide structure and has established that GalNAc beta 1----4(NeuAc alpha 2----3)Gal beta 1----4GlcNAc is a DBA binding site in the small intestine of the mouse.

A high-brightness and low-divergence neutral beam is obtained for a Zeeman polarimetry of edge plasmas on JT-60U. The electron density and the pitch angle of the magnetic field line, thus the plasma current density distribution, can be measured by the Zeeman polarimetry using the lithium beam. A thermionic ion source heated by an electron beam is developed in order to obtain the ion beam current extraction over 10 mA. The beam optics is designed after detailed numerical simulation taking the space charge effects into account because a low-divergence angle of the neutral lithium beam leads to a narrow spectrum of the beam emission. It is also necessary to keep the beam radius small for good spatial resolution due to a long beam line of 6.5 m. The newly developed ion gun is operated on a test stand which simulates the diagnostic arrangement on JT-60U. The ion beam current of 10 mA at a beam energy of 10 keV is successfully extracted from the ion source operated at the temperature over 1300 degrees C and focused by Einzel lens. The full width at half maximum radius of the ion beam at the neutralizer is about 9 mm. A sodium vapor neutralizer neutralizes the collimated ion beam fully at the temperature of 300 degrees C. The neutral beam profiles are measured at two locations of the beam line at Z=2.3 m (beam monitor position) and Z=6.5 m (plasma region). The half-width at half maximum radius of the neutral beam of 26 mm and the equivalent beam current of 3 mA with the beam divergence angle of 0.2 deg which is the half-angle divergence are obtained. Those parameters satisfy the requirements of the Zeeman polarimetry. Furthermore, a long pulse extraction with a current of 10 mA and duration of 50 s is attained.

The exchange bias behavior was observed between strain-induced ferromagnetic (FM) α′ martensite and antiferromagentic (AFM) austenitic phase in SUS 316LN stainless steel at

Recent results from the DIII-D tokamak have provided significant contributions to the understanding of many of the elements of tokamak physics and the application of this understanding to the design of next generation devices including ITER and CIT. The limitations of magnetohydrodynamic stability on the values of plasma beta (the ratio of kinetic pressure to the containing pressure of the magnetic field) that can be attained has been experimentally demonstrated and found to be described by existing theory. Values of beta (10.7%) well in excess of those required for proposed devices (ITER and CIT) have been demonstrated. Regimes of confinement (H-mode) have been established that scale favorably to proposed next generation devices, and experiments demonstrating the dependence of the energy confinement on plasma size have been completed. Understanding of confinement is rapidly developing especially in the areas of bulk transport and the role of turbulence in the plasma edge. Key experimental results in areas of plasma transport and edge plasma phenomena are in agreement with theories based on short wavelength turbulence. Control of the divertor heat loads and impurity influx has been demonstrated, and new progress has been made in the understanding of plasma edge phenomena. Experiments with ion Bernstein wave heating have not found regimes in which these waves can produce effective central ion heating. Electron cyclotron current drive experiments have demonstrated 70 kA of driven current in 400 kA discharges.

A lithium ion gun is under construction for a lithium beam Zeeman polarimetry on JT-60U. The performance of the prototype ion gun has been estimated by the numerical simulation taking the space charge effects into account. The target values of the ion gun are the beam energy of 30 keV, the beam current of 10 mA and the beam divergence angle within 0.13 degrees. The low divergence of 0.13 degrees is required for the geometry of the Zeeman polarimetry on JT-60U wher et heobservation area is 6.5 m away from the neutralizer. The numerical simulation needs to be carried out for the design study because the requirement of the divergence angle is severe for the development of the high-brightness ion gun. The simulation results show the beam loss of 50 % caused by the clash to the electrode such as the cathode and th en eutralizer. Moreover, the beam transport efficiency from the neutralizer to the observation area is low due to the broadening of the divergence angle. The total beam efficiency is about 5 %. Extracted beam profile affects the beam focusing and the efficiency. The peaked profile achieves better efficiency than the hollow one. As a result, beam current of 1 mA is obtained at the observation area by the simulation for the prototype ion gun.

Atomic images of the semiconducting Bi−O plane on Bi2Sr2CaCu2O8+δ cleaved surface have been observed by STM. For the as-grown crystals, the images show strong modulations in the in-plane atomic interval and in the brightness. The in-plane atomic interval in the relatively bright regions (RBR) is 20∼30% smaller than that in the relatively dark regions (RDR). It is shown that the density of tunneling electrons in RBR is larger than that in RDR, that is, a kind of charge-density-wave (CDW) is formed in the Bi−O plane. Magnitudes of the structural modulation and the semiconducting gap are both reduced by annealing. Such a correlation suggests that the origin of the semiconducting Bi−O plane might be attributed to the structural modulation.

The magnetic susceptibility χ of La2−xSrxCuO4 was measured in the range x=0.06 to 0.3. The T-dependent part χs(T) of χ below x=0.18 consists of a term χFs(T) arising from antiferromagnetically correlated Cu-spins, while χs(T) above x=0.18 consists of χFs(T) and a Curie term which is small but grows with increasing x. The superconducting transition temperature decreases rapidly with increasing x above x⋍0.18 where the Curie term appears.

Emphases in JT-60 experiments are placed on (1) lower-hybrid (LH) current drive characteristics with a multi-junction type launcher, and (2) the confinement study with combination of neutral beam injection LH current drive and pellet injection. The new multi-junction LH launcher provides a sharp N/sub /// spectrum with high directivity for N/sub ///=1-3.4. The current drive efficiency and the radial distribution of high energy electron production show clear correlation with injected N/sub ///: the current drive efficiency has the maximum at low N/sub ///( approximately 1.3) while flattening of plasma current is more effective in large N/sub ///. A broad radial distribution of high energy electron current and approximately 30% reduction in sawtooth inversion radius were obtained by high N/sub /// ( approximately 2.5) LH injection. To fully suppress the sawtooth activity, low N/sub /// ( approximately 1.3) injection was found to be more effective. Improved energy confinement has been obtained with hydrogen pellet injection. Energy confinement time was enhanced up to 40% relative to usual gas fuelled discharges. The discharge has a strongly peaked electron density profile with ne(0)/(ne) approximately 5 and ne(0) approximately 2.0*1020 m-3. The improved discharges are characterized by a strongly peaked pressure profile within the q=1 magnetic surface, and degrades when a large sawtooth recovers or the pressure gradient may reach a critical value. When large (3 mm, 4 mm) and fast (2.2 km/s) pellets were injected, 30% energy confinement improvement was obtained even during the NB heating of 14 MW. Further investigations of IDC characteristics have been made. The oxygen impurity lines from the main plasma and the main radiative loss drop first. Then the plasma stored energy starts to rise. The particle recycling is reduced around the main plasma, and is localized in the neighborhood of the X-point with a time lag of approximately 0.2 sec. Eventually the discharge shows a significant remote radiative cooling power at the divertor region.

The characteristics of a toroidal discharge with qa ≈ 1/2 is studied on TORIUT-6. Ultra low q equilibria that are stable against the global kink mode are realized through MHD relaxation and are shown to be characterized by dq/dr < 0 and a hollow current profile. The stable state lasts for 600 μs, which is of the order of the classical diffusion time. These experimental observations are consistent with non-linear MHD simulation results.

REPUTER-I is a conceptual design study on a compact reversed field pinch fusion reactor with a solid breeder blanket. The first wall is structurally independent from the blanket. The blanket is composed of SiC reinforced blocks which form a stable arch, and the stresses in SiC are basically compressive. Pressurized water is chosen for the first wall and as a limiter coolant in order to remove a high heat flux, while helium gas is used for the blanket coolant. A pile of thin Li2O tiles and thick beryllium tile provides a satisfactory tritium breeding ratio. A pumped limiter is shown to meet the demand for heat and particle exhaust removal in a compact RFP core. Magnet system design and plasma performance analysis are made as well on the first wall, blanket and limiter design.

The characteristics of plasmas with the safety factor q between that of tokamaks and that of reversed field pinches were studied on the OHTE device, with toroidal fields of up to 3.9 kG and plasma currents of up to 140 kA. Plasmas in this regime (0 < q < 1) are called ultra-low q plasmas. The discharges are globally stable and last much longer than the resistive decay time of the current. A unique feature of most discharges is a series of plateaus in the current (or equivalently q) as the current decreases in a 'staircase' fashion. The plateau q is related to the major rational ratios (1/4, 1/3, 1/2, 1, etc.), suggesting plasma self-organization. Profile measurements show that the q-profile is somewhat different from those of the Taylor relaxed states. The soft X-ray temperature measurement indicates that the plasma has burned through the radiation barrier.

1. It is generally recognized that the transition part of the lip shows special attitude in some lesions such as Behget's syndrome. The author attempted to made the histological and histopathological studies on the rabbit lip to evaluate the reason of the above mentioned clinical speciality of the transition part comparing with the skin and the mucous membrane of the lip.2. The fine structure of the rabbit lip with special regard to the distribution of the small vessels were observed by intravascular injection of resin or India ink. In the transitition part, the epitheliar layer is thickest, the papillae show marked development, and the small vessels in the connected tissue are abundant compared with the other parts.3. The histological changes of the lip were observed in the rabbits which had been previously put in allergic state with subcutaneous injection of bovine blood serum and resensitized by the intraarterial injection of the antigen through the external maxillary artery. Slight serous inflammation was observed in each part.4. When adrenalin was added as a modified element at the time of resensitization, the allergic histological change which showed the type of serous exudative inflammation increased generally.5. In case that adjuvant was added, the change increased strikingly as serous exudative inflammation.6. Through the above three experiments of sensitization, the allergic histological changes were observed stronger in the transition part than the other parts.7. The similar allergic histological changes were observed also in the lung, heart and kidney.8. From those results, the present author concluded that the special attitude of the transiton part of the lip against Behget's syndrome was probably explained by the allergic theory.

低温タール中油の概略の平均組成を知るために, 粗中油を硫酸およびアルカリで処理して酸製性分, 塩基成分, オレフイン分を求め, 残部の中性油分については環分析によつてパラフィン鎖, ナフテン環, 芳香族環を求めた。その結果から, 200～300deg;Cの溜分の成分の分布状態を検討して, 高溜分になるほど酸性分は減少し, パラフィン鎖が増加するが, 他の成分にはあまり大きな変化がないことを認めた。

The effect of several antivitamin B6 on gamma-aminobutyric acid (GABA) metabolism was studied in the rat retina. The rat electroretinogram (ERG) was also recorded after administration of these drugs. Aminooxyacetic acid (AOAA) and hydrazine administration increased the GABA content and inhibited the GABA degrading enzyme, GABA transaminase in retina. In addition, there drugs elongated the peak latency of the oscillatory potential in the rat ERG. In contrast, 4-deoxypyridoxine (DOP) or isonicotinic acid hydrazide (INAH) administration decreased the GABA content and inhibited the GABA synthesizing enzyme, glutamic acid decarboxylase in retina, and administration of these drugs together with AOAA lessened the degrees of elevation of GABA content and of the elongation of the peak latency produced as compared with AOAA alone, though neither of the former drugs had a significant effect on ERG. The retinal GABA seems to play an important role in relation to the oscillatory potential of ERG.

Poly-N-acetyllactosamines were prepared from Ehrlich carcinoma cells cultured in the presence of [14C]galactose. Methylation analysis indicated that 31% of the galactose was in the non-reducing end. Of it, 77% was cleaved by alpha-galactosidase, and 56% was released as a disaccharide by endo-beta-galactosidase C. Methylation analysis confirmed that the released disaccharide was mostly Gal alpha 1----3Gal. Therefore, Gal alpha 1----3Gal structure, not Gal alpha 1----3(Gal alpha 1----6)Gal structure, was the major alpha-galactosyl structure in the poly-N-acetyllactosamines synthesized. Furthermore, alpha-galactosidase digestion did not change the content of disubstituted galactosyl residues. Thus, Gal alpha 1----3(Gal alpha 1----6)Gal structure, which was suggested to be the sole non-reducing terminal structure of poly-N-acetyllactosamines of Ehrlich carcinoma cells, was not detected in significant amounts under the present experimental conditions.

Limited proteolysis of bovine S-antigen with alpha-chymotrypsin resulted in the accumulation of three peptides of MW 24,000, 16,000, and 12,000 daltons, respectively. By ELISA (enzyme-linked immunosorbent assay), MW 24,000 peptide was found to react with anti-S antibodies, but the other two peptides did not react with the antibodies under the assay conditions. The reactive peptide was separated from the smaller peptides by gel filtration on Sephadex G-75 and Sephadex G-50. When the MW 24,000 peptide was injected into Lewis rats, severe to mild uveitis was produced in all injected animals. The results indicate that the pathogenic determinant is on the MW 24,000 peptide.

With use of a multimachine pedestal database, essential issues for each regime of ELM types are investigated. They include (i) understanding and prediction of pedestal pressure during type I ELMs, a reference operation mode of a future tokamak reactor; (ii) identification of the operation regime of type II ELMs, which have small ELM amplitude with good confinement characteristics; (iii) identification of the upper stability boundary of type III ELMs for access to the higher confinement regimes with type I or II ELMs; (iv) understanding the relation between core confinement and pedestal temperature in conjunction with the confinement degradation in high density discharges. Both scaling and model based approaches for expressing pedestal pressure are shown to roughly scale the experimental data well and could be used to make initial predictions for a future reactor. q and delta are identified as important parameters for obtaining the type II ELM regime. A theoretical model of type III ELMs is shown to reproduce the upper stability boundary reasonably well. It is shown that there exists some critical pedestal temperature below which the core confinement starts to degrade. It is also shown that it is possible to obtain improved pedestal conditions for good confinement in high density discharges by increasing the plasma triangularity.

The maximum normalized beta achieved in long-pulse tokamak discharges at low collisionality falls significantly below both that observed in short pulse discharges and that predicted by the ideal MHD theory. Recent long-pulse experiments, in particular those simulating the International Thermonuclear Experimental Reactor (ITER) [M. Rosenbluth et al., Plasma Physics and Controlled Nuclear Fusion (International Atomic Energy Agency, Vienna, 1995), Vol. 2, p. 517] scenarios with low collisionality nu(e)*, are often limited by low-m/n nonideal magnetohydrodynamic (MHD) modes. The effect of saturated MHD modes is a reduction of the confinement time by 10%-20%, depending on the island size and location, and can lead to a disruption. Recent theories on neoclassical destabilization of tearing modes, including the effects of a perturbed helical bootstrap current, are successful in explaining the qualitative behavior of the resistive modes and recent results are consistent with the size of the saturated islands. Also, a strong correlation is observed between the onset of these low-m/n modes with sawteeth, edge localized modes (ELM), or fishbone events. consistent with the seed island required by the theory. We will focus on a quantitative comparison between both the conventional resistive and neoclassical theories, and the experimental results of several machines, which have all observed these low-min nonideal modes. This enables us to single out the key issues in projecting the long-pulse beta limits of ITER-size tokamaks and also to discuss possible plasma control methods that can increase the soft beta limit, decrease the seed perturbations, and/or diminish the effects on confinement. (C) 1997 American Institute of Physics.

The nonlinear dynamics and structure of plasmas with tightly twisted magnetic field lines have been studied using a toroidal plasma device. Stepwise magnetohydrodynamic (MHD) relaxation occurs, resulting in a discontinuous change in the pitch of magnetic field lines. This discrete nature of the pitch stems from the instability of kink (torsional) modes. The MHD relaxation stabilizes kink modes by selecting (self-organizing) appropriate pitches. The self-organized state displays the characteristic of a ‘dissipative structure’ in that it is accompanied by enhanced energy dissipation; the global resistance of the plasma current is substantially enhanced. The magnetic energy, which is generated by the internal plasma current, first changes into fluctuation energy through the kink instability, and then it goes mainly to ion thermal energy through viscous dissipation of the fluctuating flow. The viscosity dissipates the fluctuation energy with conservation of helicity. The self-organization of the stabilized magnetic field is characterized by the preferential conservation of the helicity.