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This paper brings together the chief points raised during FM5 by astronomers, archaeologists, and historians whose research interests centred on novæ and supernovæ. The common focus was the use of historical observations to study transient astronomical phenomena. The presenters covered a wide variety of topics within that theme, and this report summarizes some of the aspects specific to historical novæ and supernovæ.
Vitamin K is considered to be involved in the pathological mechanisms of coronary artery calcification (CAC). Correlation between CAC and plasma vitamin K levels was studied. A total of 103 patients, with at least one coronary risk factor, were studied. CAC was measured using 64-slice multislice computed tomography (MSCT) and divided into three groups: none (CAC score = 0; n 25), mild to moderate (0 < CAC score < 400; n 52) and severe (CAC score > 400; n 26). Phylloquinone (PK) and menaquinone (MK)-4 and MK-7 were measured by HPLC-tandem MS. Mean age of patients was 64 (sd 13) years, of which 57 % were male. Median CAC score was 57·2. Median levels of PK, MK-4 and MK-7 were 1·33, 0 and 6·99 ng/ml, showing that MK-7 was the dominant vitamin K in this population. MK-7 showed a significant inverse correlation with uncarboxylated osteocalcin (ucOC, P = 0·014), protein induced by vitamin K absence of antagonist-2 (PIVKA-2, P = 0·013), intact parathyroid hormone (P = 0·007) and bone-specific alkaline phosphatase (P = 0·018). CAC showed an inverse correlation with total circulating uncarboxylated matrix Gla protein (t-ucMGP, P = 0·018) and Hb (P = 0·05), and a positive correlation with age (P < 0·001), creatinine, collagen type 1 cross-linked N-terminal telopeptide (NTX, P = 0·03), pulse wave velocity (P < 0·001) and osteoprotegerin (P < 0·001). However, CAC did not have a significant correlation with plasma levels of PK, MK-4 or MK-7. In conclusion, plasma MK-7, MK-4 or PK level did not show significant correlation with CAC despite the association between plasma vitamin K levels and vitamin K-dependent proteins such as ucOC or PIVKA-2.
InP/Si engineered substrates formed by wafer bonding and layer transfer have the potential to significantly reduce the cost and weight of III-V compound semiconductor solar cells. InP/Si substrates were prepared by He implantation of InP prior to bonding to a thermally oxidized Si substrate and annealing to exfoliate an InP thin film. Following thinning to remove damage caused by the implantation and exfoliation from the surface of the InP transferred film, InGaAs solar cells lattice-matched to bulk InP were grown on those substrates using metal-organic chemical vapor deposition. The photovoltaic current-voltage characteristics of the InGaAs cells fabricated on the wafer-bonded InP/Si substrates were comparable to those synthesized on commercially available epi-ready InP substrates, thus providing an initial demonstration of wafer-bonded InP/Si substrates as an alternative to bulk InP substrates for solar cell applications.
CeO2 thin films as insulating layers for high-temperature superconducting digital devices were studied. The dependence on substrate temperature and oxygen pressure of the surface morphology and crystallinity of CeO2 thin films prepared by pulsed laser deposition were investigated. CeO2 thin films with a flat and closely grained surface were obtained at a relatively low oxygen pressure of 3.6 Pa, whereas higher oxygen pressure led to CeO2 thin films with a rough surface and columnar grains. The recovery of oxygen content in superconducting layers was examined for multilayer structures with CeO2 thin films. Enough oxygen was supplied to the upper and lower superconducting layers when the multilayer was cooled slowly in 3 × 10−4 Pa oxygen pressure after deposition. Resistively shunted junction type I-V characteristics were confirmed for interface-engineered ramp-edge junctions in a multilayer structure including four superconducting layers with CeO2 thin films.
Y0.9Ba1.9La0.2Cu3Oy (La-YBCO) thin films were prepared by an off-axis magnetron sputtering method on MgO substrates with and without a BaZrO3 buffer layer. Insertion of BaZrO3 buffer layer was effective for obtaining La-YBCO films with pure c-axis orientation and in-plane alignment at low temperatures below 600 °C. We prepared La-YBCO thin films on BaZrO3-buffered MgO substrates using a temperature-gradient method, in which a template La-YBCO layer was first deposited at 600 °C, and then the temperature was continuously raised to 700 °C. By this method, La-YBCO thin films with improved crystallinity were successfully prepared. It was also proved that the insertion of the BaZrO3 buffer layer enables us to prepare high-quality La-YBCO films with high reproducibility.
The internal friction of a silicon nitride with a sintering aid of yttrium oxide was measured from room temperature to 1400 °C. A mechanical loss peak was typically observed at 1000 °C on heating the as-sintered specimen; however, it disappeared on cooling. Also, the peak was not observed upon heating a specimen that had been heated above 1400 °C. When we carried out thermal cycling, raising terminal temperatures from 1050 to 1400 °C, the integrated intensity of the peak gradually decreased due to the progressive crystallization of a grain-boundary amorphous phase.
A family of rare-earth metal manganites are antiferromagnetic (AFM) ferroelectrics and some of these may show also weak ferromagnetism. First we will show how to observe the ferroelectric (FEL) and AFM domain structures by the interference effects of second harmonic generation (SHG). Second, the observed clamping of the AFM domain wall (DW) to the FEL domain boundary (DB) is intuitively explained by the group theoretical consideration of the magnetic anisotropy energy depending upon the sign of the FEL polarization. Third, the application of these clamped DW-DB to the memory engineering will be briefly discussed.
The amount of absorbed hydrogen, the absorption rate and the reversibility of hydrogen absorption-desorption reaction were measured for binary systems R-M (R= Y, La, Ce; M=Co, Rh, Ir, Ni, Pd, Pt). These experimental results were discussed by comparing the number of states unoccupied by electrons, the cohesive energy and the energy fluctuation, which were calculated by the extended Hückel method. The main results are as follows. (a) The more the number of unoccupied electronic states in the compounds, the more hydrogen is absorbed, (b) the critical concentrations of hydrogen in the R-M compounds where the energy fluctuation decreases remarkably correspond to the inflection or saturation points in the absorption curve, and (c) when the cohesive energy of a compound decreases linearly with hydrogen concentration, the compound easily desorbs hydrogen. On the other hand, when a sharp knickpoint is observed in the curve of cohesive energy - hydrogen concentration, the desorption reaction is hard to occur.
c-Axis-oriented (Hg0.9Re0.1)Ba2CaCu2Oy thin films were grown on the (100) plane of SrTiO3 substrates by a so-called two-step process. Transmission electron microscopic observation revealed that, in the film annealed under a higher temperature, some steplike regions appeared at the top layer of SrTiO3 substrate. High-resolution transmission electron microscopic images showed that the lattice parameters in these regions are about 4.05–4.15 Å, being longer than the lattice parameter of SrTiO3. It is supposed that a chemical reaction occurred in these regions, and a phase of (Bax,Sr1−x)(Cuy,Ti1−y)O3δs was formed by partially substituted Ba for Sr and Cu for Ti.
We report estimates for the extragalactic background light (EBL) in the K band (2.2 μm), obtained by the integration of galaxy counts down to K=25 mag in the Subaru Deep Field (SDF, 2′ x 2′). We have obtained deep galaxy count data by using the 8.2m Subaru telescope, with a total integration time of 10 hours and an average seeing of about 0.4 arcsec. The 5-sigma limiting magnitude is K=23.5, and 350 objects are detected brighter than this magnitude. There has been a significant discrepancy between previous K-count observations, probably because of the systematic uncertainties in the completeness correction. To overcome this problem, we have paid special attention to selection effects and completeness corrections, with realistic theoretical galaxy models taken into account consistently. The faint-end slope is significantly flatter than some earlier observations of K counts, and our results suggest that the bulk of the extragalactic light in this band has been resolved as discrete sources. We estimate the value of the EBL flux obtained from the integration of our counts as 9.8 ± 1.0 nWm−2 sr−1.
The industry is strongly interested in integrating low-κ dielectrics with Damascene copper. Otherwise, with conventional materials, interconnects cannot continue to scale without limiting circuit performance. Integration of copper wiring with silicon dioxide (oxide) requires barrier encapsulation since copper drifts readily in oxide. An important aspect of integrating copper wiring with low-κ dielectrics is the drift behavior of copper ions in these dielectrics, which will directly impact the barrier requirements and hence integration complexity.
This work evaluates and compares the copper drift properties in six low-κ organic polymer dielectrics: parylene-F; benzocyclobutene; fluorinated polyimide; an aromatic hydrocarbon; and two varieties of poly(arylene ether). Copper/oxide/polymer/oxide/silicon capacitors are subjected to bias-temperature stress to accelerate penetration of copper from the gate electrode into the polymer. The oxide-sandwiched dielectric stack is used to overcome interface instabilities occurring when a low-κ dielectric is in direct contact with either the gate metal or silicon substrate. The copper drift rates in the various polymers are estimated by electrical techniques, including capacitance-voltage, current-voltage, and current-time measurements. Results correlate well with timeto-breakdown obtained by stressing the capacitor dielectrics. Our study shows that copper ions drift readily into fluorinated polyimide and poly(arylene ether), more slowly into parylene-F, and even more slowly into benzocyclobutene. A qualitative comparison of the chemical structures of the polymers suggests that copper drift in these polymers may possibly be retarded by increased crosslinking and enhanced by polarity in the polymer.
(Ba1−xLax)3Cu3(O, F)y films were prepared using a sol-gel method. Phases, the c lattice parameters of which are about 13.8, 13.1, and 11.6 Å, respectively, were formed in the films. The compound with the c parameter of ˜13.8 Å is considered to be a Ba2−xLaxCuO2F2+δ which has the La2CuO4-type structure inserted with fluorine. The compound with the c parameter of ˜11.6 Å is thought to have a three-layered structure of the perovskite block which is arisen by ordering between La and Ba elements. The films containing these compounds showed some interesting anomalies in SQUID measurements. However, no film showed a drastic decrease of electrical resistance.
Biaxially aligned YSZ thin films with strong  fiber texture were formed on a polycrystalline Ni-based alloy by off-normal ion-beam-assisted deposition. Growth structures were characterized by x-ray diffraction (XRD), transmission electron microscopy (TEM), atomic force microscopy (AFM), etc., and the alignment mechanism was discussed using a selective growth model. Peculiar structural evolution of the crystalline orientation was observed and its development was well described by an exponential equation. It was explained as a collaboration of an anisotropic growth condition and epitaxial crystallization. The  fiber texture was formed by columnar structures of diameter of 30–100 nm, which were composed of 5–10 nm diameter crystallites. Very smooth surfaces were observed by AFM imaging with a roughness of 2–3 nm and a peculiar ripple structure. The origin of the azimuthal alignment was discussed with emphasis on the surface structure of YSZ films produced using ion-beam-assisted deposition (IBAD) and the etching rate measurements of (100) surfaces of YSZ single crystals.
A systematic near-infrared survey was made for globular clusters in the Magellanic Clouds. Two infrared stars were discovered in NGC419 (SMC) and NGC1783 (LMC). NGC419 and NGC1783 are well-studied rich globular clusters whose turn-off masses and ages are estimated MTO ~ 2.0 Mʘ and т ~1.2 Gyr for NGC419, and MT0 ~ 2.0 Mʘ and т ʘ 0.9 Gyr for NGC1783, respectively.
The periods of the infrared light variations were determined to be 540 dfor NGC419IR1 and to be 480 d for NGC1783IR1, respectively. Comparison of the measurements with the period—if magnitude relation for carbon Miras in the LMC by Groenewegen and Whitelock(1996) revealed that the Kmagnitudes of the infrared stars were fainter by about 0.3 — 0.8 magnitude than those predicted by the P — K relation. This deviation can be explained if the infrared stars are surrounded by thick dust shells and are obscured even in the K band. The positions of NGC419IR1and NGC1783IR1 on the P — K diagram suggest that AGB stars with the main sequence masses of about 2 Mʘ start their heavy mass-loss when P ʘ 500 d.
Biaxially aligned YBa2Cu3O7−x (YBCO) films were fabricated on random Ni-based alloy tapes with yttrium stabilized-zirconia (YSZ) buffer layers deposited by ion-beam-assisted deposition (IBAD). Ar+ ion bombardment was found to have two significant effects on the crystalline structure of the YSZ buffer layers: to align a  axis with the substrate normal and a  axis with the bombarding beam axis. The resulting YSZ films were biaxially aligned on the random polycrystalline tapes, and the azimuthal distribution of the a- and b-axes of YBCO films on the top of the YSZ films was restricted to 10° FWHM. A critical current density (Jc) of 1.13 × 106 A/cm2 (77 K, 0 T) was obtained, and 1.1 × 105 A/cm2 was maintained at 5 T (77 K, B⊥c). The existence of both intrinsic and extrinsic pinning properties was clearly observed in the angular dependence of Jc with B⊥I. The longitudinal field effect on Jc was clearly observed, which indicated straight transport currents. This is evidence for strongly coupled current paths that demonstrate the bulk pinning properties of YBCO.
Although presently classified as a SU UMa-type dwarf nova, WZ Sge is well known as one of the most peculiar objects in that it shows only superoutbursts with exceptional duration and amplitude, and no normal outbursts. Furthermore, on its decline from the 1978 outburst, WZ Sge showed a deep temporal dip. All of these characteristics have puzzled both theoreticians and observers.
The dwarf nova AL Com was photometrically observed during the outburst in 1995 April, which occurred for the first time since 1975. The striking similarity of AL Com to WZ Sge, as demonstrated by the present observation (Fig. 1), provides plenty of material in interpreting the enigmatic nature of WZ Sge-type dwarf novae.
The ER UMa-type, including ER UMa, V1159 Ori and RZ LMi, is a subgroup of SU UMa-type dwarf novae. Outbursts of these stars are characterized by: (i) the extremely short recurrence time of the superoutburst (~ 40 d in ER UMa and V1159 Ori, ~ 20 d in RZ LMi), (ii) short outbursts with short recurrence times (~ 4 d) between the bright states, and (iii) extremely long duty cycles (~ 0.5). Assuming that the mass transfer rate from the secondary is ten times higher than that of ordinary SU UMa stars, which was invoked by Kato & Kunjaya (1995), and a weak tidal torque in the case of RZ LMi, Osaki (1996) showed that the light curves of these stars can be reproduced by the disk instability model, which does not require mass transfer bursts. These indicate that ER UMa, V1159 Ori and RZ LMi are not on the natural extension of SU UMa-type dwarf novae.
We have developed successfully the combined ion beam and molecular beam epitaxy (CIBMBE) system with a newly designed Knudsen cell for Si effusion. The CIBMBE system was applied to the epitaxial growth of Sil., Cx alloy thin films on Si using low-energy ( 100 – 300 eV ) C+ ion beam. Preliminary results on the characterization of the deposited films suggest high potential and reliability of the new Knudsen cell for Si effusion, as well as high ability of the CIBMBE method to produce thermally non-equilibrium materials. In addition, they indicate that the value of x decreases with increasing IC, which suggests that the selective sputtering for deposited C atoms by incident C+ ion beams takes place during CIBMBE processing. Precipitates of β-SiC were also found to be formed in the deposited films, whose amount was observed to increase with increasing IC.