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Context. The quasar 3C 279is among the most extreme blazars in terms of luminosity and variability of flux at all wavebands. Its variations in flux and polarization are quite complex and therefore require intensive monitoring observations at multiple wavebands to characterise and interpret the observed changes.

Context.The quasar-type blazar 3C 454.3was observed to undergo an unprecedented optical outburst in spring 2005, affecting the source brightness from the near-IR to the X-ray frequencies. This was first followed by a millimetric and then by a radio outburst, which peaked in February 2006.

Context.In spring 2005 the blazar 3C 454.3was observed in an unprecedented bright state from the near-IR to the hard X-ray frequencies. A mm outburst peaked in June–July 2005, and it was followed by a flux increase at high radio frequencies.

Institute of Space and Astronautical Science (ISAS/JAXA) in collaboration with Mitsubishi Heavy Industries (MHI) has developed fuel and gas tanks for reaction control system and orbital control system of satellites; A tank is fabricated through welding of two thin, hemi-spherical or conical parts, which are fabricated by superplastic blow forming. Mass-productivity is not an important factor but the forming precision and flexibiliry in the process are important for this application. ISAS and MHI, therefore, developed a new blow-forming technique, which has high flexibility in terms of tank size because it requires a furnace but not a hot-press machine. Some typical propulsion tanks fabricated through this process are presented.

High power Large Orbit Gyrotron (LOG) [1] is now under development at FIR FU. First version of this device was recently manufactured and then assembled with power supply ETIGO-IV [2]. Results of preliminary tests of electron-optic system are presented. The conditions when stableflat form of current pulse realized are discussed. Analytical estimations of cathode-anode distance to achieve small influence of cathode plasma during high voltage (HV) pulse are performed.

High power Large Orbit Gyrotron (LOG) [1] is now under development at FIR FU. First version of this device was recently manufactured and then assembled with power supply ETIGO-IV [2]. Results of preliminary tests of electron-optic system are presented. The conditions when stable flat form of current pulse realized are discussed. Analytical estimations of cathode-anode distance to achieve small influence of cathode plasma during high voltage (HV) pulse are performed.

Abstract. Short-pulse powerful Large Orbit Gyrotron with total electron energy about 400 kV and beam power in the cavity up to 100 MW is now under developing at FIR FU. Suitable for 200 ns pulse duration electron-optic system is analyzed. Results of numerical simulation for explosion emission cusp-type electron guns and magnetic field intensity about 8 T are presented. Sensitivity of the guns to small deviations from the nominal operating regime is investigated. Some versions of the gun with different accelerating potential as well as different beam current passing through the cavity (60-300A) are suggested. Current reduction simplifies the problems of mode competition and potential depression in the cavity, but at the same time decrease output power. To diminish current special diaphragms are suggested. Results of numerical simulation of collector corresponding to each version of the gun design including power density distributions along its surface are presented. It is shown that beam quality and collector regimes are suitable for LOG operation.

In the article, results of numerical simulation of the gun with the cusp of magnetic field are presented. Short pulse version of the gun with explosion emission is investigated. Some preliminary analytical estimation of the beam and gun parameters are performed. Then, numerical optimization of the electrodes shape as well as magnetic field distribution is carried out. For preliminary separation of electrons and formation of the rectilinear beam, anode diaphragm is installed. After then, additional selection of electrons for decreasing the ripple is performed. For this purpose, channel walls are used for interception of some part of the electron beam. Reverse of the magnetic field in the diode part of the gun is formed. So, the formation of the rectilinear beam is combined with the region, where electrons obtain initial gyration energy. To prevent the disperse action of the own beam space charge forces, the system with big gradient of magnetic field (about 0.5-1 kGs/mm) is needed. According to results of the simulation, helical electron beam can be performed even at total compression ratio about 1000 and current density more than 50 kA/cm2. The designed electron gun provides acceptable performance for the large orbit gyrotron, such as operating current close to 300 A, the pitch-factor value about 1.5-1.7, deviation of the guiding centers from the axis (the ripple) λ/10 and λ/6 for operation on 3-rd and 5-th cyclotron harmonic correspondingly (wavelength λ=0.5 and 0.3 mm) and velocity spread within the range 10-15%.

The adsorption state of ammonia (NH3) on the ZnO(10&onemacr;0) surface has been investigated using photoelectron spectroscopy (PES) and near-edge X-ray absorption fine structure (NEXAFS) spectroscopy. The core-level and valence-band PES measurements reveal that ammonia adsorbs molecularly via its N atom on ZnO(10&onemacr;0) and that no dissociated species are formed at room temperature. The orientation of adsorbed NH3 is investigated by the polarization-dependent N K-edge NEXAFS measurements, and it is found that the C3v molecular axis of NH3 is inclined in the [000&onemacr;] direction with the tilt angle of 33°−41° from the surface normal.

AbstractWe have previously reported that spaceflight and tail suspension enhanced degradation of rat myosin heavy chain (MHC) in association with activation of a ubiquitindependent proteolytic pathway [Ikemoto et al., FASEB J. 15 (2001), 1279 1281]. To elucidate whether the ubiquitination is accompanied by oxidative stress, we measured markers for oxidative stress, such as thiobarbituric acidreactive substance (TBARS) and glutathione disulfide (GSSG), in gastrocnemius muscle of tailsuspended rats. Glutathione (GSH) concentration in the muscle significantly decreased from day 5 and reached a minimum value on day 10. Tail suspension reciprocally increased concentrations of TBARS and GSSG in parallel with enhancement of protein ubiquitination, suggesting that oxidative stress may play an important role in protein ubiquitination caused by tail suspension. To prevent ubiquitination associated with oxidative stress, we also administered an antioxidative nutrient, cysteine, to tailsuspended rats. Intragastric supplementation of 140 mg/rat of cysteine for 2 weeks or longer normalized the ratio of GSH to GSSG in the muscle and suppressed protein ubiquitination and MHC fragmentation, compared with supplementation of the equimolar amount of alanine. The cysteine supplementation significantly suppressed the loss of hindlimb muscle mass. Our results suggest that supplementation of antioxidative nutrients, such as cysteine, may be beneficial for preventing ubiquitination of muscle proteins caused by unweighting.

Perimesencephalic nonaneurysmal subarachnoid haemorrhage (PN-SAH) is characterised by accumulation of blood around the midbrain, normal angiographic findings and an excellent prognosis. The etiology of PN-SAH has not yet been determined. Therefore we decided to compare the venograms of patients with PN-SAH with those of patients with aneurysmal SAH (A-SAH) in order to examine the relationship between PN-SAH and venous structures. We retrospectively studied 6 patients with PN-SAH and 102 cases of angiographically evaluated A-SAH during the past 12 years by reviewing their venograms for possible abnormalities in venous structures, particularly in the basal vein of Rosenthal (BVR). More abnormalities in venous structures were found in the patients with PN-SAH than in those with A-SAH. Most of the BVR in the patients with PN-SAH appeared to drain into various dural sinuses instead of the galenic system. The relationship between PN-SAH and abnormalities in venous structures was determined.

The new experimental systems for investigating the photo-induced phenomena have been constructed. They consist of the photoelectron spectroscopy system based on the synchrotron radiation, the laser system based on the mode-locked pulse lasers, and the experimental system for time-resolved measurements. The systems have been applied to study the surface photo-voltage (SPV) effects on the surfaces of GaAs (100) and GaAs-GaAsP superlattice. The results showed that the temporal profiles of the surface photo-voltage effects have several components in the nano- and micro-second ranges, which depend on the surface conditions.

Valence band structures in various phases of an organometal spin-crossover complex [Fe(2-pic) 3 ]Cl 2 - EtOH have been measured by means of photoelectron spectroscopy based on the combination of synchrotron radiation and laser light. The valence band structure showed the remarkable change due to the photo-induced (PI) phase transition (PIPT) at low-temperatures (LTs) as well as the thermally induced phase transition (TIPT), but the structure of the PI phase was very different from that of the high-temperature (HT) phase. The DV-X f calculation based on the [Fe-(NH 3 ) 6 ] octahedron was also carried out for comparison, indicating that the electronic structure originating from Fe and N ions is closely related to the PIPT.

A √3×√3-(Pb,Sn) surface was studied by means of scanning tunneling microscopy (STM) and core-level photoelectron spectroscopy (PES) to identify its local atomic arrangement. Observed spots in STM were classified into three types, which were white and gray (α), gray and white (β), and black and gray (γ) spots in the filled- and empty-state images, respectively. The STM images also showed a local 3×3-(Pb,Sn) arrangement in the √3×√3-(Pb,Sn) surface. Both Pb 5 d and Sn 4 d core-levels spectra indicated that there were two components on the √3×√3-(Pb,Sn) surface, and the peak positions and shapes of Pb 5 d and Sn 4 d core-levels of the √3×√3-(Pb,Sn) surface were almost the same as those of the √3×√3-Pb and √3×√3-Sn surfaces. Comparison between the heights of the STM spots on the single and binary adsorbate surfaces and their core-levels spectra suggested that Sn and Pb were located at α and β positions, respectively. The nominal coverage of the local 3×3-(Pb,Sn) arrangement was determined to be 1/9 and 2/9 ml for Sn and Pb, respectively.

Active immunization with the peptide segments rSMP-230 and YAL-198, corresponding to the hydrophilic extracellular domain of two human sperm antigens (rSMP-B and YWK-II, respectively), reduced fertility in female rats by different mechanisms. The anti-rSMP-230 antibody interferes with human and murine fertilization, and the anti-YAL-198 antibody blocks the development of mouse embryos. The authors examined in vitro at which stage the antibodies to rSMP-230 and YAL-198 were cytotoxic to murine embryos up to morula/blastocyst stage. Anti-rSMP-230 antibody was not cytotoxic to any stages. On the other hand, the anti-YAL-198 antibody arrested the growth of embryos at the 2-cell stage but not at more advanced developmental stages. When the anti-YAL-198 antibody was used, spotty staining was observed only on the surfaces of embryos that had arrested at the 2-cell stage. Unstained embryos, however, continued to develop normally. In contrast, the anti-rSMP-230 antibody stained murine sperm but failed to stain murine ova and embryos. The present results suggest that the human sperm components rSMP-B and YWK-II play important roles in sperm-egg interaction and early development of the embryo, respectively.

Sperm-immobilizing antibodies block human fertilization by interfering with the acrosome reaction (AR). To clarify the mechanism of blockage of AR by sperm-immobilizing antibodies, the authors examined their effects on the increase of intracellular free Ca 2+ concentration induced by follicular fluids (Ca 2+ influx) in spermatozoa and on their capacitation. Sperm-immobilizing antibodies did not suppress Ca 2+ influx induced by follicular fluid, but they inhibited capacitation of human spermatozoa. Namely %AR (%AR after addition of an AR inducer - %AR before treatment) induced by progesterone was significantly ( p < .0001) lower when spermatozoa were incubated in human tubal fluid medium cotaining antibody-positive serum (1.2%), compared to that when incubated in control medium (19.2%). Furthermore, the proportion of both spermatozoa that became capacitated and ones that had become capacitated decreased significantly ( p < .0001) after 2, 4, and 6 h of incubation in medium containing antisperm antibody-positive serum, compared to those of spermatozoa incubated in control medium. In conclusion, sperm-immobilizing antibodies may be closely related to their blockage of capacitation.

BACKGROUND: Leptin, which is the product of the obese gene, is believed to play important roles in pubertal development and reproductive function in females. In a study using adult male rats, it was found that leptin stimulated secretion of gonadotropin from the pituitary in a dose-related manner. However, there has been no such study in female rats. OBJECTIVE: To investigate the effects of leptin on the production of LH and FSH from the pituitary in female rats, using primary cultured pituitary cells. METHODS: In this study, we determined body weight, serum leptin concentration and serum estradiol (E(2)) concentration in female Wistar rats at 3, 5, 6, 7, 9 and 11 weeks of age, and cultured pituitary cells from 6-week-old female Wistar rats with leptin (0--10(-7) mol/l) and GnRH (0 or 10(-8) mol/l). Then basal and GnRH-stimulated extra- and intracellular LH and FSH were assayed by RIA. RESULTS: Serum leptin concentration increased with increases in body weight and E(2) concentration. The pubertal serum leptin concentration was about 10(-10) mol/l. At a lower or moderate concentration, leptin produced dose-related increases in both basal and GnRH-stimulated extra- and intracellular LH and FSH in pituitary cells. At a concentration of 10 mol/l, leptin significantly (P<0.05) stimulated both basal and GnRH-stimulated extra- and intracellular LH and FSH. However, at greater concentrations, these effects diminished. CONCLUSIONS: These results indicated that leptin induced pituitary cells to produce and secrete both LH and FSH, with or without GnRH. The concentration of leptin that induced the greatest production of gonadotropins by pituitary cells was 10(-10) mol/l, which was the same as the physiological pubertal concentration. Leptin may be involved in the onset of puberty. It is also conceivable that leptin may be a cause of ovulatory failure, not only in weight loss but also in weight gain.

Although numerous studies have investigated the relationship between cholesteryl ester transfer protein (CETP) and high density lipoprotein (HDL) remodeling, the relationship between CETP and low density lipoproteins (LDL) is still not fully understood. In the present study, we examined the effect of the inhibition of CETP on both LDL oxidation and the uptake of the oxidized LDL, which were made from LDL under condition of CETP inhibition, by macrophages using a monoclonal antibody (mAb) to CETP in incubated plasma. The 6-h incubation of plasma derived from healthy, fasting human subjects led to the transfer of cholesteryl ester (CE) from HDL to VLDL and LDL, and of triglycerides (TG) from VLDL to HDL and LDL. These net mass transfers of neutral lipids among the lipoproteins were eliminated by the mAb. The incubation of plasma either with or without the mAb did not affect the phospholipid compositions in any lipoproteins. As a result, the LDL fractionated from the plasma incubated with the mAb contained significantly less CE and TG in comparison to the LDL fractionated from the plasma incubated without the mAb. The percentage of fatty acid composition of LDL did not differ among the unincubated plasma, the plasma incubated with the mAb, and that incubated without the mAb. When LDL were oxidized with CuSO4, the LDL fractionated from the plasma incubated with the mAb were significantly resistant to the oxidative modification determined by measuring the amount of TBARS and by continuously monitoring the formation of the conjugated dienes, in comparison to the LDL fractionated from the plasma incubated without the mAb. The accumulation of cholesteryl ester of oxidized LDL, which had been oxidized for 2 h with CuSO4, in J774.1 cells also decreased significantly in the LDL fractionated from the plasma incubated with mAb in comparison to the LDL fractionated from the plasma incubated without the mAb. These results indicate that CETP inhibition reduces the composition of CE and TG in LDL and makes the LDL resistant to oxidation. In addition, the uptake of the oxidized LDL, which was made from the LDL under condition of CETP inhibition, by macrophages also decreased.

The cyclopolymerizations of two meso dianhydrohexitols, 1,2:5,6-dianhydro-3,4-di-O-methylallitol (1) and -galactitol (3), were examined to form a polymer with six-membered ring repeating units. Distinct from the cases of 1,2:5,6-dianhydro-3,4-di-O-methyl-d-mannitol (5), -l-iditol (6), and -d-glucitol (7) in which the five-membered ring units were formed with high regio- and stereoselectivity, six-membered ring units were found in polymers 2b, 4a, and 4b obtained by the polymerizations of 1 and 3. The anionic polymerization of 1 with t-BuOK was highly regio- and stereoselective to form polymer 2a consisting of five-membered ring units, but that of 3 was different in the scission mode of the epoxy groups to form polymer 4a consisting essentially of six-membered ring units. The cationic polymerization of 1 with BF3·OEt2 produced polymer 2b having a structure consisting of the six-membered ring units as major constituents and five-membered ring units as minor ones. The structure of polymer 4b from the cationic polymerization of 3 was somewhat complex, comprising unknown units and uncyclized units along with the five- and six-membered ring units. The steric hindrance in the growing ion was an advantage in forming the six-membered ring unit.

The UVSOR has been operational for nearly 14 years. In recent years, improvements to accelerators and beamlines have been carried out to obtain better performance and new scientific achievements. For example, a new type of helical undulator and a resonance transverse kicker were installed into the straight sections of the storage ring, and about one‐third of the beamlines were upgraded by installing new monochromators and an interferometer. In addition, instruments and equipment were improved for research studies, with many interesting results. The most up‐to‐date information of the UVSOR facility is presented.

Proteins ofBabesia equi piroplasms were characterized. The piroplasms ofB. equi were purified by lysis of infected horse erythrocytes with N2 gas cavitation followed by separation in Percoll density-gradient centrifugation. The relative molecular weights (Mr) of major proteins separated by two-dimensional sodium dodecyl sulfate-polyacrylamide gel electrophoresis were 18, 28, 30, 41, 43, 54, 66.5, and 96 kDa. Immunoblot analysis using serum from an experimentally infected horse revealed six immunodominant proteins of 15, 18, 28, 30, 41, and 96 kDa. Two immunodominant proteins of 18 and 28 kDa were membrane-bound proteins as revealed by Triton X-114 phase partitioning.

Immunoglobulin G (IgG) fraction was prepared from a serum obtained from an infertile woman (IS) that induced sperm agglutination of human and boar sperm. The antisperm antibodies interacted with a 50-kD boar sperm protein, determined by immunoblot. The 50-kD protein was extracted with deoxy-cholate (DOC) and purified by affinity chromatography on concanavalin A column, ion exchange chromatography on CM52 column, affinity chromatography on IS IgG-protein G-agarose, and by preparative electrophoresis with electroelution. The purified 50-kD protein migrated as a single homogeneous band when analyzed by sodium dodecyl sulfate polyacrylamide gel electrophoresis and by Western blot. The production of antibodies against specific sperm proteins may be a cause of immuno-logical infertility.