Search

Sputtering yields of molybdenum (Mo) are computed for deuterium, oxygen and carbon as impurity ions from the residual gas of the vacuum system, as well as Mo and Cs using Yamamura formula. The incident ion energy ranges from 10 keV to 1 MeV, the back-streaming ion beam energy from the extraction voltage up to ITER full acceleration potential. The sputtering yield of Cs against Mo reached ten atoms per ion and was the largest among the investigated ion species. The effect due to retention of deuterons in Mo was studied for the case of grazing angle incidence of D+ at D- ion extraction energy to confirm the small effect onto the sputtering yield; the result obtained for 10 keV D+ for 10% retention of D atoms in Mo increased the sputtering yield only by 2%. The back-streaming D+ ions at 1 MeV energy should make a layer of high concentration deuterium atoms at 6 µm depth from the Mo surface. Possible failure mode associated with the particle implantation is discussed.

Plasmodium infection depletes arginine, the substrate for nitric oxide synthesis, and impairs endothelium-dependent vasodilation. Increased conversion of arginine to ornithine by parasites or host arginase is a proposed mechanism of arginine depletion. We used high-performance liquid chromatography to measure plasma arginine, ornithine, and citrulline levels in Malawian children with cerebral malaria and in mice infected with Plasmodium berghei ANKA with or without the arginase gene. Heavy isotope-labeled tracers measured by quadrupole time-of-flight liquid chromatography-mass spectrometry were used to quantify the in vivo rate of appearance and interconversion of plasma arginine, ornithine, and citrulline in infected mice. Children with cerebral malaria and P. berghei-infected mice demonstrated depletion of plasma arginine, ornithine, and citrulline. Knock out of Plasmodium arginase did not alter arginine depletion in infected mice. Metabolic tracer analysis demonstrated that plasma arginase flux was unchanged by P. berghei infection. Instead, infected mice exhibited decreased rates of plasma arginine, ornithine, and citrulline appearance and decreased conversion of plasma citrulline to arginine. Notably, plasma arginine use by nitric oxide synthase was decreased in infected mice. Simultaneous arginine and ornithine depletion in malaria parasite-infected children cannot be fully explained by plasma arginase activity. Our mouse model studies suggest that plasma arginine depletion is driven primarily by a decreased rate of appearance.

Density distributions of negative hydrogen (H−) ions and negative deuterium (D−) ions were measured with the laser photodetachment method in the extraction region of the negative ion source. The distribution of H− ion density peaks at the center of the ion source, while that of the D− ion shows a flatter profile in the direction parallel to the plasma grid. The positive ion densities of hydrogen and deuterium estimated from the positive saturation current indicate similar profiles with different amounts close to the grid. The difference in the H− ion and D− ion distributions can be explained by the difference in the negative ion yield and the survival probability of the ions due to the isotope effect.

We report on the characteristics of the beam-generated plasma in the multibeamlet case of a hydrogen negative ion beam at NIFS. The plasma potential, and the energy of secondary particles in the drift region of an ion beam, offer an insight into the mechanisms that allow beam transport in low pressure gasses. The first measurements reported here were made by means of a four-gridded retarding field energy analyzer, combined with the measurement of the drain current at the beam dump, and with infrared beamlet monitoring technique. The retarding field analyzer measures the energy distributions of particles emitted radially from the beam-generated plasma [1]. The beam is dumped onto a graphite calorimeter, which is electrically insulated, so that it can be electrically biased and the collected current can be measured. The thermal image of the calorimeter is acquired during the beam pulse, thus offering a quantitative estimation of the single beamlet optics and multibeamlet focusing. Finally, the influence of the neutral gas density is studied by puffing hydrogen gas in this drift region. The measured ion and electron energy distribution functions are strongly affected by the electric bias of the calorimeter. For a 47kV, 0.3A beam, an electron temperature of 3eV at the plasma edge was found. The energy distribution of the ions for a pressure of about 0.03Pa is presented, from which the plasma potential can be inferred.

The consumption rate of cesium (Cs) for negative hydrogen (H-) ion source increases when the source operation gas is changed from hydrogen to deuterium. There was observed a clear indication that a deuterium discharge erodes Cs atoms on the plasma grid (PG) surface to increase work function and the co-extracted electron current. We have proposed a model, that the enhanced sputtering yield of Cs from the PG due to deuterium ions, which carries more kinetic energy to Cs adsorbed on the surface directly or indirectly, is the main reason for this fast dissipation of Cs. Introduction of helium (He) into discharge can verify the enhanced sputtering effect due to the lager mass ions in the source discharge. Comparing the effect due to seeded Cs before and after the He injection into discharge through Cs OES signals as well as the H- density measured with cavity ring-down method, the sputtering/evaporation enhancement due to He is estimated. Neutral atoms and positive ions in the He discharge should cause enhanced sputtering like deuterium, while the system does not generate neutron under the induction of acceleration voltage to diagnose the extracted negative ion beam. Plasma parameters of the H2 and He plasmas are investigated by diagnostics tools installed on NIFS-RNIS (National Institute for Fusion Science, Research and development Negative Ion Source) together with H- density measurement by cavity ring down. Enhanced consumption rate of Cs is compared with proposed sputtering yield data to predict the rate for deuterium operation of negative ion sources.

Magneto-optical Faraday effect is widely applied in optical devices and is indispensable for optical communications and advanced information technology. However, the bismuth garnet Bi-YIG is only the Faraday material since 1972. Here we introduce (Fe, FeCo)-(Al-,Y-fluoride) nanogranular films exhibiting giant Faraday effect, 40 times larger than Bi-YIG. These films have a nanocomposite structure, in which nanometer-sized Fe, FeCo ferromagnetic granules are dispersed in a Al,Y-fluoride matrix.

The properties of cesium (Cs) recycling due to back-streaming ions have been investigated using an optical emission spec-troscopy in the hydrogen negative ion (H−) source with a slot-type grounded grid (GG). The slot-type GG performed well to enhance the beam performance, and to reduce the thermal loading on GG by high transparency. We clearly observed increase of Cs optical emission intensity during beam extraction owing to the increase of the Cs ions sputtered from the back plate of the source due to the back-streaming positive hydrogen ions. Increase of Cs is closely related with the extracted H− current, but it does not depend on the beam energy. Recycling Cs from the back plate is deeply relevant to the perveance condition of the H− beam, and is minimized at the optimum perveance. Strong Cs recycling from the back plate owing to the back-streaming ions is promoted in the high perveance condition with large divergence, which is consistent with the numerical calculation for the distribution of back str...

Carbonization treatment successfully converted textile sludge into potential adsorbent. The carbonization was performed at the range of 400 to 800 °C without oxygen involved. In order to investigate the adsorption performance of carbonized sludge then a series of adsorption tests was carried out. Adsorption experiments indicated that the highest adsorption capacity was obtained at the carbonization temperature of 400 °C. The maximum adsorption capacity for removal textile dye of reactive red 231 on aqueous sollution was reached 49.1 mg/g. The pH of carbonized sludge played a significant role in the adsorption of reactive red 231 in the solution. Since the reactive red 231 is categorized as an anionic dyes, the lower pH was appropriate to accelerate adsorption process through charge neutralization by abundant H+ ions.

The achievements of the deuterium beam operation of a negative-ion-based neutral beam injector (N-NBI) in the large helical device (LHD) are reported. In beam operation in LHD-NBIs, both hydrogen (H) and deuterium (D) neutral beams were generated by changing the operation gas using the same accelerator. The maximum accelerated deuterium negative-ion current () reaches 46.2 A from two beam sources with the averaged current density being 190 A m−2 for 2 s, and the extracted electron to accelerated ion current ratio () increases to 0.39 using 5.6 V high bias voltage in the first deuterium operation in 2017. An increase of electron density in the vicinity of the plasma grid (PG) surface, which is considered the main reason for the increase of co-extracted electrons in a beam, is confirmed by the half-size research negative-ion source in the neutral beam test stand at the National Institute for Fusion Science (NIFS). The deuterium negative-ion density is also larger than the hydrogen negative-ion density in the vicinity of the PG surface using the same discharge conditions. In the latest experimental campaign in 2018, increases to 55.4 A with the averaged current density being 233 A m−2 for 1.5 s using the shot extraction gap length. The low of 0.31 can be maintained by using high discharge power. The various parameters mentioned above are defined in detail below.

The dominant electron scattering mechanisms in GaAsN were investigated by analysing the Hall electron mobility and photoluminescence (PL) spectrum. The GaAsN thin films were grown by chemical beam epitaxy. The temperature dependence of the electron mobility indicated that polar optical phonon (POP) scattering was dominant in GaAs and GaAs:N0.0003 near room temperature. By increasing nitrogen compositions up to around 0.1%, the temperature dependence of the electron mobility became from T-1.23 to T-0.5. It indicated that the dominant scattering changed from POP to alloy scattering with nitrogen composition. The full width at half maximum of the PL spectra suggested that the large potential fluctuation at conduction band edge did not exist in GaAsN grown by chemical beam epitaxy. The theoretical electron mobility of POP and alloy scattering with large effective mass which was obtained by Masia et al., Dennecker et al., and Ibanez et al. agreed with the determined electron mobility. Therefore, the POP and alloy scattering with the large effective mass were considered to be the origin of the low electron mobility of GaAsN. (© 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

The sulfonylurea receptor 2A (SUR2A) is an ATP-binding cassette (ABC) protein that forms the regulatory subunit of ATP-sensitive potassium (K(ATP)) channels in the heart. ATP binding and hydrolysis at the SUR2A nucleotide binding domains (NBDs) control gating of K(ATP) channels, and mutations in the NBDs that affect ATP hydrolysis and cellular trafficking cause cardiovascular disorders. To date, there is limited information on the SUR2A NBDs and the effects of disease-causing mutations on their structure and interactions. Structural and biophysical studies of NBDs, especially from eukaryotic ABC proteins like SUR2A, have been hindered by low solubility of the isolated domains. We hypothesized that the solubility of heterologously expressed SUR2A NBDs depends on the precise definition of the domain boundaries. Putative boundaries of SUR2A NBD1 were identified by structure-based sequence alignments and subsequently tested by exploring the solubility of SUR2A NBD1 constructs with different N and C termini. We have determined boundaries of SUR2A NBD1 that allow for soluble heterologous expression of the protein, producing a folded domain with ATP binding activity. Surprisingly, our alignment and screening data indicate that SUR2A NBD1 contains two putative, previously unidentified, regulatory elements: a large insert within the β-sheet subdomain and a C-terminal extension. Our approach, which combines the use of structure-based sequence alignments and predictions of disordered regions combined with biochemical and biophysical studies, may be applied as a general method for developing suitable constructs of other NBDs of ABC proteins.

Background. Dose-dependent response makes certain pediatric brain tumors appropriate targets for high-dose chemotherapy with autologous hematopoietic stem-cell rescue (HDCT-AHSCR).Methods. The clinical outcomes and toxicities were analyzed retrospectively for 18 consecutive patients ≤19 y/o treated with HDCT-AHSCR at UCLA (1999–2009).Results. Patients' median age was 2.3 years. Fourteen had primary and 4 recurrent tumors: 12 neural/embryonal (7 medulloblastomas, 4 primitive neuroectodermal tumors, and a pineoblastoma), 3 glial/mixed, and 3 germ cell tumors. Eight patients had initial gross-total and seven subtotal resections. HDCT mostly consisted of carboplatin and/or thiotepa ± etoposide (n=16). Nine patients underwent a single AHSCR and nine ≥3 tandems. Three-year progression-free and overall survival probabilities were 60.5% ± 16 and 69.3% ± 11.5. Ten patients with pre-AHSCR complete remissions were alive/disease-free, whereas 5 of 8 with measurable disease were deceased (median followup: 2.3 yrs). Nine of 13 survivors avoided radiation. Single AHSCR regimens had greater toxicity than ≥3 AHSCR (P<.01).Conclusion. HDCT-AHSCR has a definitive, though limited role for selected pediatric brain tumors with poor prognosis and pretransplant complete/partial remissions.

Aims: To isolate and characterize copper-resistant halophilic bacteria from the polluted Maruit Lake, Egypt and identify the role of plasmids in toxic metal resistance. Methods and Results: We isolated strain MA2, showing high copper resistance up to the 1·5 mmol l−1 concentration; it was also resistant to other metals such as nickel, cobalt and zinc and a group of antibiotics. Partial 16S rRNA analysis revealed that strain MA2 belonged to the genus Halomonas. Copper uptake, measured by atomic absorption spectrophotometery, was higher in the absence of NaCl than in the presence of 0·5–1·0 mol l−1 NaCl during 5–15 min of incubation. Cell fractionation and electron microscopic observation clarified that most of the copper accumulated in the outer membrane and periplasmic fractions of the cells. Plasmid screening yielded two plasmids: pMA21 (11 kb) and pMA22 (5 kb). Plasmid curing resulted in a strain that lost both the plasmids and was sensitive to cobalt and chromate but not copper, nickel and zinc. This cured strain also showed weak growth in the presence of 0·5–1·0 mol l−1 NaCl. Partial sequencing of both plasmids led to the identification of different toxic metals transporters but copper transporters were not identified. Conclusions: The highest cell viability was found in the presence of 1·0 mol l−1 NaCl at different copper concentrations, and copper uptake was optimal in the absence of NaCl. Plasmid pMA21 encoded chromate, cobalt, zinc and cadmium transporters, whereas pMA22 encoded specific zinc and RND (resistance, nodulation, cell division) efflux transporters as well as different kinds of metabolic enzymes. Copper resistance was mainly incorporated in the chromosome. Significance and Impact of the Study: Strain MA2 is a fast and efficient tool for copper bioremediation and the isolated plasmids show significant characteristics of both toxic metal and antibiotic resistance.

Miyagawa S, Takeishi S, Yamamoto A, Ikeda K, Matsunari H, Yamada M, Okabe M, Miyoshi E, Fukuzawa M, Nagashima H. Survey of glycoantigens in cells from α1-3galactosyltransferase knockout pig using a lectin microarray. Xenotransplantation 2010; 17: 61–70. © 2010 John Wiley & Sons A/S. Abstract: Background: Glycoantigens represent major obstacles to successful xenotransplantation. Even after the α1-3galactosyltransferase (GalT) gene knockout (GalT-KO) pigs were produced, non-Gal antigens continue to be present. This study reports on lectin blot analyses for endothelial cells (EC) and fibroblasts from GalT-KO pigs. Methods: Differences in glycoantigens that are produced on cell surfaces in humans and pigs were surveyed. Differences between ECs and fibroblasts from wild-type and GalT-KO pigs were also examined. EC and fibroblasts from GalT-KO pigs (heterozygous and homozygous) with N-acetylglucosaminyltransferase-III (GnT-III), a wild-type EC from the sibling, human EC lines, HUVEC (human EC from umbilical veins), & HAOEC (human EC from aortas), and human fibroblast line were used. EC and fibroblasts were cultured in gelatin-coated dishes for several days. After sonication and centrifugation, the supernatant protein from each cell was labeled with Cy3, applied to a lectin array and scanned with an SC Profiler, and analyzed using an Array Pro Analyzer. Results: The pig EC showed higher signals in Euonymus Europaeus (EEL) & Griffonia simplicifolia I-B4 (GSI-B4), binds α-Gal, and in Wisteria Floribunda (WFA), Helix pomatia (HPA), Glycine max (SBA), & Griffonia simplicifolia I-A4 (GSI-A4), binds GalNAc including the Thomsen-Friedenreich precursor (Tn)-antigen, while the human EC showed strong signals in Ulex europaeus I (UEA-I), Maackia amurensis (MAL), Erythrina cristagalli (ECA), & Trichosanthes japonica I (TJA-I) instead. The EC from the GalT-KO pig signals for EEL & GSI-B4 disappeared and those for Bauhinia purpurea alba (BPL), HPA, SBA, & GSI-A4 were greatly diminished as well, while it up-regulated signals for Sambucus Nigra (SNA), Sambucus sieboldiana (SSA), & TJA-I, bind α2-6 sialic acid, compared to the wild-type pig EC. Concerning fibroblasts, the signals for HPA, SBA, & GSI-A4 were the most intense in the wild-type, and the intensities for homozygous-KO were less, approaching those of humans. In addition, the order of the intensities, as detected by Arachis hypogaea (PNA) & Maclura pomifera (MPA), binding Galβ1-2GalNAc, indicates that the Thomsen-Friedenreich (T)-antigen is likely present on pig fibroblasts. Conclusion: It is possible that the T-antigen and Tn-antigen related to GalNAc are non-Gal antigens, but, fortunately, not only α-Gal but also GalNAc were found to be decreased in the KO-pig.

We have investigated chemical-state-resolved in-depth profiles of SiO2/SiN stack films using angular-dependent photoemission spectroscopy and maximum-entropy method (MEM). MEM enables to reproduce the gate-stack structure from angular-dependence of core-level spectra, and it is utilized to determine atomic concentration of the interfacial layer. In-depth profile of the SiO2/SiN stack film reveals that the SiO2 layer is distributed in the surface region and that the SiN layer is partly oxidized, which is well related to nitrogen bonding states analyzed by angular-dependence of N 1s core-level spectra. Copyright © 2008 John Wiley & Sons, Ltd.

We have developed a method to precisely determine the band offsets for hafnium oxide (HfO2), hafnium silicate (HfSiO) and nitrided hafnium silicate (HfSiON) films on Si by elimination of x-ray irradiation effects with time-dependent photoemission spectroscopy (PES) and x-ray absorption spectroscopy. The core-level PES spectra shift during PES measurements, which is explained as the dielectric films charging due to photoemission by the x-ray irradiation. For elimination of the x-ray irradiation effect on the determination of the band offsets, time-dependent photoemission spectroscopy was performed. The precisely determined valence band offsets for HfO2, HfSiO and HfSiON are 3.2, 3.4, and 1.9 eV, respectively. On the other hand, the conduction band offsets are almost the same values of about 1.3 eV. Thus, the elimination of x-ray irradiation effect enables to precisely determine the band offsets, leading to the accurate estimation of gate leakage current. Copyright © 2008 John Wiley & Sons, Ltd.

We have applied the spectroscopic photoemission and low energy electron microscope to study high- k gate dielectrics and have performed the following in situ operations during ultrahigh vacuum annealing: real-time observation of surface morphology and microregion photoelectron spectroscopy measurements. Changes in surface morphology and electronic states were consistent with the models previously reported in the case of HfO 2 /Si. No clear differences between void regions and nonvoid regions have been observed in microregion photoelectron spectra for poly-Si/HfO 2 /Si, regardless of phase separation in real space. These results have suggested that the initial void formation occurs in about 100-nm wide regions for both HfO 2 /Si and poly-Si/HfO 2 /Si.

Palladium chalcogenides of PdS, Pd17Se15, PdSe2, PdTe, Pd3Te2 and PdSeTe were prepared by milling elemental mixtures, using a planetary-type ball mill at room temperature. These chalcogenides were obtained within 30 min. Pd17Se15 was also obtained when the elemental mixture was immersed in methanol or ethanol at room temperature for 10 days.

Two pilot-scale polyvinylidene fluoride (PVDF) microfiltration (MF) membranes with different structures (i.e. symmetric and asymmetric) were operated after coagulation/sedimentation, sand filtration, and chlorination. Turbidity was removed completely. Moreover, humic substances, Al, and Fe were removed very well by the pilot-scale system. An asymmetric membrane (HFS membrane) having a nominal pore size of 0.05 μm showed relatively high removal efficiency of the small organic matter (about 6,000 Da) than a symmetric membrane (HFM membrane) having a nominal pore size of 0.1 μm. However, the extracted inorganic concentrations of the HFM membrane were relatively higher than that of the HFS membrane. Therefore, it could be concluded that the HFS membrane better reduced membrane fouling than the HFM although the nominal pore size of the former was half of the latter. To control microbial growth and mitigate membrane fouling, a NaOCl solution was injected into the effluent of sand filtration before the both membranes. However, it adversly affected membrane fouling due to the oxidization of inorganic substances such as Al, Fe, and Mn.

Inhibition of nitric oxide (NO) signaling may contribute to pathological activation of the vascular endothelium during severe malaria infection. Dimethylarginine dimethylaminohydrolase (DDAH) regulates endothelial NO synthesis by maintaining homeostasis between asymmetric dimethylarginine (ADMA), an endogenous NO synthase (NOS) inhibitor, and arginine, the NOS substrate. We carried out a community-based case-control study of Gambian children to determine whether ADMA and arginine homeostasis is disrupted during severe or uncomplicated malaria infections. Circulating plasma levels of ADMA and arginine were determined at initial presentation and 28 days later. Plasma ADMA/arginine ratios were elevated in children with acute severe malaria compared to 28-day follow-up values and compared to children with uncomplicated malaria or healthy children (p, Author Summary During a malaria infection, the vascular endothelium becomes more adhesive, permeable, and prone to trigger blood clotting. These changes help the parasite adhere to blood vessels, but endanger the host by obstructing blood flow through small vessels. Endothelial nitric oxide (NO) would normally counteract these pathological changes, but NO signalling is diminished malaria. NO synthesis is inhibited by asymmetric dimethylarginine (ADMA), a methylated derivative of arginine that is released during normal protein turnover. We found the ratio of ADMA to arginine to be elevated in Gambian children with severe malaria, a metabolic disturbance known to inhibit NO synthesis. ADMA was associated with markers of endothelial activation and impaired tissue perfusion. In parallel experiments using mice, the enzyme responsible for metabolizing ADMA, dimethylarginine dimethylaminohydrolase (DDAH), was inactivated after infection with a rodent malaria. Based on these studies, we propose that decreased metabolism of ADMA by DDAH might contribute to the elevated ADMA/arginine ratio observed during an acute episode of malaria. Strategies to preserve or increase DDAH activity might improve NO synthesis and help to prevent the vascular manifestations of severe malaria.

We have observed photoluminescence (PL) decay persisting for more than 104 s at low temperatures in hydrogenated amorphous Si (a-Si:H). The very-long-lived PL decay was identified by the third peak in the lifetime distribution using frequency-resolved spectroscopy. This residual PL decay fits the derivative of a stretched exponential function and its time integral agrees with light-induced electron spin resonance (LESR) densities. At low temperatures and low generation rates, the monomolecular distant-pair reaction dominates the recombination kinetics at extremely long times after stopping the illumination.

Micro-photoluminescence is used to study the temperature dependence of CdTe self-assembled quantum dots. The observation of the micro-photoluminescence spectra with temperature shows that there are two different structures, namely the zero-phonon line and the phonon sidebands. When the temperature increases, the sidebands become clearer and show substantial broadening. The experimental data are reproduced well by a theoretical model taking into account the carrier-acoustic-phonon coupling. (© 2006 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

A long-pulse plasma discharge of more than 30 min duration was achieved on the Large Helical Device (LHD). A plasma of ne = 0.8 × 1019 m−3 and Ti0 = 2.0 keV was sustained with PICH = 0.52 MW, PECH = 0.1 MW and averaged PNBI = 0.067 MW. The total injected heating energy was 1.3 GJ. One of the keys to the success of the experiment was a dispersion of the local plasma heat load to divertors, accomplished by sweeping the magnetic axis inward and outward. Causes limiting the long pulse plasma discharge are discussed. An ion impurity penetration limited further long-pulse discharge in the 8th experimental campaign (2004).

A long-pulse plasma discharge for more than 30 min. was achieved on the Large Helical Device (LHD). A plasma of ne = 0.8× 1019 m−3 and Ti0 = 2.0 keV was sustained with PICH = 0.52 MW, PECH = 0.1 MW and averaged PNBI = 0.067 MW. Total injected heating energy was 1.3 GJ, which was a quarter of the prepared RF heating energy. One of the keys to the success of the experiment was a dispersion of the local plasma heat load to divertors, accomplished by shifting the magnetic axis inward and outward.

High-Z plasmas have been produced with Ar and/or Ne gas fuelling to increase the ion temperature in Large Helical Device (LHD) plasmas heated with high-energy negative-ion-based neutral beam injection (NBI). Although the electron heating is dominant in the high-energy NBI heating, the direct ion heating power is significantly enhanced in low-density plasmas due to both an increase in the beam absorption (ionization) power and a reduction of the ion density in the high-Z plasmas. Intensive neon- and/or argon-glow discharge cleaning works well to suppress dilution of the high-Z plasmas with wall-absorbed hydrogen. As a result, the ion temperature increases with an increase in the ion heating power normalized by the ion density and reaches 10 keV. An increase in the ion temperature is also observed with the addition of centrally focused electron cyclotron resonance heating to a low-density and high-Z NBI plasma, suggesting improvement of the ion transport. The results obtained in the high-Z plasma experiments with high-energy NBI heating suggest that an increase in the direct ion heating power and improvement of the ion transport are essential to ion temperature rise, and that a high-ion temperature could be obtained as well in hydrogen plasmas with low-energy positive-NBI heating which is planned in the near future in the LHD.

A local island divertor (LID) experiment has begun on LHD, with the aims of controlling edge recycling and improving the plasma confinement. The fundamental divertor functions of the LID have been demonstrated in the recent experiments. From the particle flux profile measurements on the LID head it was found that the particles diffusing out from the core region are well guided along the island separatrix to the LID head. Owing to the closed configuration around the LID head, evidence of the high efficient pumping was observed, together with a strong capacity to screen impurities. The first results of edge modeling using the EMC3-EIRENE code are also presented.

Nickel/titanium supermirrors with critical reflection angles θc of m=3–5 times the critical angle of total reflection of natural Ni θcNi were fabricated on silicon substrates 3 in . in diameter and 3 mm in thickness by a DC magnetron sputtering system using the facing targets technique, and the neutron reflectivity of the supermirrors was evaluated for cold neutrons of 8.8 A in wavelength. The supermirrors with 532 layers and with 468 layers achieved a reflectivity of 84% and 53% at their θc of m=2.9 and 3.7, respectively, while supermirrors with more than 630 layers had reduced reflectivity at angles smaller than θc. This reduction resulted from the formation of a non-multilayered pillar structure due to the growth of interface roughness between layers. Using supermirrors with m not more than 3, we designed a paraboloidal focusing mirror and proposed a prototype to obtain approximately 5 times the utilizable neutrons at the focal point for cold neutrons of 8 A .

The phonon bottleneck effect is studied in InAs/GaInP quantum dots (QDs). The time-resolved photoluminescence spectra from the lowest ( n =1) and second lowest ( n =2) exciton states in QDs are measured in the temperature range of 5– 200 K . We find that the rise time of the n =1 level is about 500 ps when the excitation energy is in resonance with the n =2 level. This is a long time compared to about 200 ps in non-resonant excitation, and therefore the bottleneck effect exists between the levels n =2 and 1. In order to understand the source of the bottleneck, the temperature dependence of carrier relaxation time between the exciton levels is investigated in the assigned temperature range. With increasing temperature, the relaxation time decreases to 200 ps at 200 K . The data are in good agreement with the theoretical fit of the relaxation probability for multi-phonon processes.

Micro-photoluminescence ( μ -PL) is used to study the temperature dependence of self-assembled quantum dots (QD) in semiconductors. The observation of the PL with temperature shows that there are two different states within the PL emission, namely the zero-phonon line and the phonon sidebands. When the temperature increases, the effect of the sidebands become clearer and show substantial broadening. The theory also shows good agreement with the experimental data, and in the present experiments, PL and μ -PL spectra have been measured at temperatures of 5 K ⩽T⩽90 K in both CdTe and GaAs self-assembled QD samples.

We present results on the influence of temperature on the exciton lineshape in self-assembled III–V semiconductor quantum dots. Micro photoluminescence (μ-PL) is used to observe the temperature dependence of the exciton line in self-assembled GaAs and InGaAs semiconductor single quantum dots (QDs). The observation of the PL with temperature shows that there are two different states within the PL emission, namely the zero-phonon line and the phonon sidebands. The sidebands and the zero-phonon line both show non-linear characteristics with respect to temperature. When the temperature increases, the effect of the sidebands become clearer and show substantial broadening. The theory also shows good agreement with the experimental data, and in the present experiments, PL and μ-PL spectra have been measured at temperatures of 5K ≤ T ≤ 90 K in GaAs and InGaAs self-assembled QD samples. (© 2004 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

The zona pellucida (ZP) surrounding the mammalian oocyte is composed of three glycoprotein components (ZPA, ZPB, and ZPC). Mammalian sperm bind to carbohydrate chains of a ZP glycoprotein in the initial phase of fertilization. Sperm-ligand carbohydrate chains have been characterized in mouse, cow, and pig. In pigs, triantennary/tetraantennary neutral complex-type chains from ZPB/ZPC mixture possess stronger sperm-binding activity than those of biantennary chains (Kudo et al., 1998: Eur J Biochem 252:492-499). Most of these oligosaccharides have beta-galactosyl residues at the nonreducing ends. This study used two in vitro competition assays to investigate the participation of the nonreducing terminal beta-galactosyl residues of the ligand active chains in porcine sperm binding. The removal of the nonreducing terminal beta-galactosyl residues from either the ligand active carbohydrate chains or endo-beta-galactosidase-digested glycoproteins significantly reduced their inhibition of sperm-egg binding, indicating that the beta-galactosyl residues at the nonreducing ends are involved in porcine sperm-egg binding. A correlation between the sperm-binding activity and in vitro fertilization rate is also presented.

Summary Background A number of studies support the belief that human basophils play an important role in allergic inflammation. The exact mechanism of basophil activation at the site of allergic inflammation, however, has not been well understood, mainly due to their low number in blood and difficulty in obtaining a sufficient number of highly purified basophils for investigation. Objective The purpose of this study is to expand human basophils in vitro with high yield and purity by culturing peripheral blood stem cells (PBSCs). Methods We collected PBSC-rich mononuclear cells containing CD34+ cells (0.15–4.9%) by leukapheresis from patients with malignant lymphoma and lung cancer during haematopoietic recovery after chemotherapy plus granulocyte colony-stimulating factor-induced mobilization. PBSC-rich mononuclear cells were cultured in the presence of IL-3. Results When PBSC-rich mononuclear cells containing more than 1% of CD34+ cells were cultured, 20.0–83.3% of the cells, mostly with a yield of >10%, were metachromatic cells after 3 weeks of culture. These cells resembled mature peripheral blood basophils morphologically when examined by light and electron microscopy. Flow cytometric analysis showed that they expressed both FcɛRI and FcγRII. FcɛRI cross-linking resulted in intracellular calcium mobilization, histamine release and synthesis of cysteinyl leukotrienes. The intracellular histamine content and the release of these chemical mediators triggered by anti-IgE antibodies were comparable to those of peripheral blood basophils. Conclusion These findings suggest that PBSC-derived basophils expanded in vitro are morphologically and functionally mature and will be a useful tool for the analysis of basophil functions.

Introduction The Hanganutziu-Deicher (H-D) antigen with terminal N-glycolyl neuraminic acid-(NeuGc) is widely distributed in mammalian species including monkeys and apes, but is not found in humans and birds. After the knock out of α1, 3galactosyltransfease, the H-D antigen became a major antigen of the “non-Gal antigen.” The expression of NeuGc is controlled by the activity of cytidine monophospho-N-acetylneuraminic acid hydroxylase (CMAH). In this study, molecular cloning of pig CMAH was performed, as the first step in producing H-D knockout pigs. Methods A pig endothelial cell line, MYP30, was used. The DNA sequence of pig CMAH was queried in dbEST (NCBI) using the BLAST program to search for cDNA fragments of pig CMAH, based on an alignment analysis of the mouse CMAH sequence. A polymerase chain reaction experiment was performed and candidate cDNA clones were isolated. To obtain the 5′-end and 3′-end of the open reading frame sequence, a 5′-full RACE Core Set and 3′-full RACE Core Set were used. Results We cloned and characterized the pig CMAH gene. The ATG is located in exon 4, which corresponds to the mouse gene, and the stop codon is in exon 17. In the case of the 5′ site of the gene, exon 3 was identified but exons 1 and 2 are still being investigated. On the other hand, exon 18 was newly identified in the 3′ site of the gene. Conclusion The results represent useful information for future clinical xenotransplantation studies.

Isothermal phase relations in the Au-Sb-Te system have been investigated at 350°C by the reactions of pure elements of Au, Sb and Te in evacuated sealed glass tubes. Microprobe techniques were employed to determine the composition of each phase of the products. Most efforts were concentrated on the pseudo-binary join between AuSb2, aurostibite and AuTe2, calaverite and the phase relations between these phases and phases in the Sb and Te binary system. Two ternary phases whose compositions are Au1.9(Te2.645b0.46)3.1 and AuSbTe(phase A) were found to exist stably at 350 °C. The XRD pattern of the former phase is almost similar to that of montbrayite reported by BACHECHI (1972), but the composition of the former phase does not agree well with that, and the latter phase does not seem to have been reported as a distinct phase. Montbrayite shows some little solid solution field and has non-stoichiometric compositions. The composition of montbrayite in the present study is not located on the (Au,Sb)2Te3 stoichiometric line, but near the Au2(Te,Sb)3 line. Calaverite, AuTe2 dissolved AuSb2 components up to 11.8 mole per cent and aurostibite, AuSb2 dissolve less than 1 mole per cent AuTe2 component. The phase relations in the system were characterized by the tie line of tellerantimony, Sb2Te3 and gold, Au in the central portion of the diagram, by which independent two ternary systems were introduced, that is, the Au-Sb-Sb2Te3 and the Au-Sb2Te3-Te systems. As a result, right side phases in Figure 3, aurostibite(AuSb2), antimony(Sb) and δ phase ((Sb,Te) solid solutions,ss) in the former system do not coexist with left side phases, calaverite(AuTe2 ss), montbrayite, and tellurium(Te) in the latter system.

Objective To assess fibroblast growth factor-2 (FGF2/bFGF), which is important in the development and maintenance of the normal prostate and in the development of human benign prostatic hyperplasia (BPH) and prostatic carcinoma, in an animal model of experimentally induced diabetes. Materials and methods Using Western blotting and immunohistochemical analyses, the expression of FGF2 in prostates from several groups of rats was investigated. Rats had diabetes for 8 or 16 weeks (induced by intravenous injection with 65 mg/kg streptozotocin); rats were also treated with insulin (starting 8 weeks after the induction of diabetes, for 8 weeks), and two further groups acted as age-matched control rats. Immunohistochemical markers for smooth muscle (α-actin) and epithelium (cytokeratin) were used to distinguish different cell types in adjacent prostatic sections. Results Diabetic rats had smaller prostates and lower serum testosterone levels than their controls; insulin treatment of diabetic rats increased prostatic size and testosterone levels. As shown by Western blotting, diabetes caused greater FGF2 expression than in controls, whereas reverse-transcriptase polymerase chain reaction studies showed similar levels of prostatic FGF-2 mRNA in all groups. Immuno-histochemical studies showed that FGF-2 was expressed in both stromal and epithelial components of the rat prostate. Furthermore, although the expression of FGF2 was higher in epithelial than stromal cells in control prostates, it was distributed uniformly in the diabetic prostate. Conclusion The differences in the level of expression and pattern of distribution of FGF2 suggests a potential role for FGF2 in the changes observed in prostatic growth in diabetic rats.

DNA extracted from formalin-fixed and paraffin-embedded brain tissue is known to contain as yet ill-characterized inhibitors of the PCR process. As part of a project that aims to clarify the role of mitochondrial DNA sequence variation in human neurodegenerative diseases using DNA from various ethnic backgrounds, we have investigated factors that influence the preservation of archival DNA and its suitability for PCR. In this study, neuropathological tissue samples were analysed that had been routinely processed in 18 international centres on four continents. Following DNA extraction, PCR amplification of mitochondrial and nuclear DNA sequences was performed with and without additional purification of the template DNA. In addition, the DNA used for PCR was analysed by HPLC. Phosphate-buffered formalin proved to be a superior fixative compared with unbuffered aldehyde: DNA extraction resulted in greater yields, the molecular weight of the isolated DNA was higher and PCR was more successful. PCR inhibitors were identified as (1) high concentrations of small (

We have successfully produced almost linearly polarized X-ray beam by extracting Transition Radiation (TR) X-rays through a rectangular slit 3 mrad long and 0.2 mrad wide placed downstream of a 7.5-μm thick Kapton foil stack radiator bombarded with a 1-GeV electron beam. Our calculation predicted that the linearity of TR photon was 94% for both a vertical and a horizontal slit. The measured results for the vertical slit agreed with the calculation, and the linearity of obtained TR X-ray beam was more than 90%. For the horizontal slit, the measured results differed from our expectations due to a prolonged electron beam profile. In the polarization measurement of TR photon we used the Bragg reflection on a lithium fluoride crystal [LiF(200)] which acted as both a polarimeter and a spectrometer.

The sequential membrane system and electrospray ionization mass spectrometry are investigated on their usefulness for characterizing aquatic humic substances. In this research, the Suwannee River Fulvic Acid (SRFA) was used for the investigation. For the mass spectrometry, the optimum analytical conditions were determined. Two indices (i.e., the total ion intensity and the averaged molecular weight) obtained from the spectrum were found relevant for evaluating the physical characteristics of aquatic humic substances. The repetitious peaks at a discrete of 14 Da in the lower m/z range of the acquired spectrum suggested that the SRFA has the –CH2– based structure in its lower molecular weight region. For the sequential membrane system, the optimum operating conditions were determined. The SRFA could be fractionated and concentrated by this system. The significant difference of the averaged molecular weight among the concentrated fractions from the different size membranes indicated thatthis system is useful for the fractionation and concentration of the aquatic humic substances.