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Notes: 11B and 10B magic-angle spinning nuclear magnetic resonance (MAS NMR) spectroscopy was conducted to characterize cubic boron nitride films prepared by plasma chemical vapor deposition. Similarities and differences between cubic boron nitride films and polycrystals synthesized at high pressure and high temperature were clarified by chemical shift and linewidth. The same local structure and tetrahedral symmetry of boron atoms in both forms was demonstrated, and a higher defective density appeared to exist in the film form, agreeing well with results from Raman measurements. Noncubic-phase impurities, i.e., amorphous, turbostratic, and hexagonal phases, in films were also detected in 11B MAS NMR spectra, and the possibility of removing these impurities by chemical etching was demonstrated. © 2001 American Institute of Physics.

Notes: The ecosystems of Tierra del Fuego (in southern Patagonia, Argentina) are seasonally exposed to elevated levels of ultraviolet-B radiation (UV-B: 280–315 nm), due to the passage of the ‘ozone hole’ over this region. In the experiments reported in this article the effects of solar UV-B and UV-A (315–400 nm) on two UV-B defence-related processes: the accumulation of protective UV-absorbing compounds and DNA repair, were tested. It was found that the accumulation of UV-absorbing sunscreens in Gunnera magellanica leaves was not affected by plant exposure to ambient UV radiation. Photorepair was the predominant mechanism of cyclobutane-pyrimidine dimer (CPD) removal in G. magellanica. Plants exposed to solar UV had higher CPD repair capacity under optimal conditions of temperature (25 °C) than plants grown under attenuated UV. There was no measurable repair at 8 °C. The rates of CPD repair in G. magellanica plants were modest in comparison with other species and, under equivalent conditions, were about 50% lower than the repair rates of Arabidopsis thaliana (Ler ecotype). Collectively our results suggest that the susceptibility of G. magellanica plants to current ambient levels of solar UV-B in southern Patagonia may be related to a low DNA repair capacity.

Notes: Background and objectives The epidemiological association between higher dietary n-3 polyunsaturated fatty acids (PUFA) and lower prevalence of asthma, has led to interest in the role of early dietary modification in allergic disease prevention. In this study we examined the effects of maternal n-3 (PUFA)-rich fish oil supplementation on cord blood (CB) IgE and cytokine levels in neonates at risk of developing allergic disease.Methods In a randomized double-blind, placebo-controlled trial, 83 atopic pregnant women received either fish oil capsules (n = 40) containing 3.7 g n-3 PUFA/day or placebo capsules (n = 43) from 20 weeks gestation until delivery. CB cytokine levels (IL-4, IL-5, IL-6, IL-10, IL-12, IL-13, TNF-α and IFN-γ) and total IgE levels were measured and compared between the two groups. Fatty acid composition of red cell membranes was analysed by gas chromatography and the relationships among PUFA, cytokine and IgE levels were examined.Results Maternal fish oil supplementation resulted in a significant increase in n-3 PUFA levels (P 〈 0.001) in neonatal erythrocyte membranes. Neonates whose mothers had fish oil supplementation had significantly lower plasma IL-13 (P 〈 0.05) compared to the control group. There was also a significant inverse relationship between levels of n-3 PUFA in neonatal cell membranes and plasma IL-13. There was no difference in levels of IgE and the other cytokines measured.Conclusions This study provides preliminary evidence that increasing neonatal n-3 PUFA levels with maternal dietary supplementation can achieve subtle modification of neonatal cytokine levels. Further assessment of immune function and clinical follow-up of these infants will help determine if there are any significant effects on postnatal immune development and expression of allergic disease.

Notes: This study examined the success of titanium (Ti) removable partial dentures (RPDs) compared with that of cobalt–chromium (Co–Cr) RPDs using a randomized controlled clinical trial. Thirty-eight RPD patients were provided with either Co–Cr (20 patients) or Ti (18 patients) RPDs. The total numbers of dentures was 31 (13 maxillary, 18 mandibular) for Co–Cr and 23 (11 maxillary, 12 mandibular) for Ti. Patients were reviewed for 24 months following denture issue. After the initial 12 months, 20 clinical problems were recorded and became the criteria for subsequent assessment. Incidence of failure was analysed using both Fisher's exact test and the chi square test at a significance level of P〈0·05. Fracture of retainers in both metals occurred only in the first 12 months. Some failure types presented at significantly higher levels in the first 12 months but there were no significant differences between the two in all the criteria examined between the 12- and the 24-month reviews. Although differences existed in failure types between Co–Cr and Ti RPDs during the early review stages, the overall success rate of Ti RPDs was comparable with that of Co–Cr RPDs after 24 months. The higher incidence of failures in Ti RPDs prior to the 12-month review suggests the importance of taking its lower rigidity into account when designing RPDs.

Notes: Immunohistochemical localization of CEA, CA19-9 and DU-PAN-2 in hepatitis C virus-infected liver tissues Aims: We investigated expression of CEA, CA19-9 and DU-PAN-2 in liver tissues of chronic hepatitis, liver cirrhosis and hepatocellular carcinoma, measuring their serum value to clarify their clinical significance, and proliferating cell nuclear antigen (PCNA) was assessed in serial sections to determine whether expression of these molecules in chronic liver disease was related to regeneration of biliary ducts. Methods and results: Liver tissues were biopsied under peritoneoscopy or echo-guidance and resected surgically among 63 patients with anti-hepatitis C virus-positive sera. There were 26 cases of chronic hepatitis, 21 cases of liver cirrhosis and 16 cases of hepatocellular carcinoma (four cases of mixed type). They were simultaneously used for immunocytochemistry for CEA, CA19-9 and DU-PAN-2, and PCNA was demonstrated in serial liver tissues by immunohistochemistry. Serum CEA, CA19-9 and DU-PAN-2 were measured by radioimmunoassay or enzyme immunoassay. In chronic hepatitis and liver cirrhosis CEA immunoreactivity was seen on membranes facing bile canaliculi and in bile ductules. Both CA19-9 and DU-PAN-2 immunoreactivity were observed in bile ductules in chronic hepatitis liver cirrhosis and non-neoplastic areas surrounding hepatocellular carcinoma, and CA19-9 was also present in interlobular bile ducts. PCNA immunoreactivity was not detected in marker-positive bile ductules or interlobular bile ducts. In hepatocellular carcinoma CEA immunoreactivity was seen on membrane facing dilated bile canaliculi in glandular structures, and CEA, CA19-9 and DU-PAN-2 immunoreactivity was observed in cholangiolar areas in mixed type of hepatocellular carcinoma. Conclusions: CEA in chronic hepatitis and liver cirrhosis is expressed not only in bile ductules but also on membrane facing bile canaliculi, and both CA19-9 and DU-PAN-2 were seen in different levels of biliary ducts. These molecules were expressed in bile ductules in surrounding non-neoplastic areas of hepatocellular carcinoma, and their expression was not associated with regeneration of biliary ducts. CEA expression was present in the trabecular type of hepatocellular carcinoma, and CA19-9 and DU-PAN-2 were observed in cholangiolar areas in mixed type of hepatocellular carcinoma.

Notes: A synchrotron radiation X-ray powder diffractometer for samples of very small amount has been developed to collect high-quality diffraction patterns under extreme conditions, i.e. at low temperature and/or high pressure. A new cylindrical imaging plate (CIP) is used as a detector, in addition to a conventional flat-type imaging plate (FIP). By using the CIP system, the diffraction data in a diffraction angle range −44 ≤ 2θ ≤ 122° are collected with a dynamic range of about 106. The alignment of the diffractometer, measurement and analysis are automatically operated by a workstation. A performance test shows that the CIP system has spatial resolution of about 0.07° with a dynamic range of 106. The diffraction pattern of a standard sample of Si measured by the CIP system has high quality; the refinement of the structure reaches Rw = 3.68% even in the case of a small amount of sample (about 2 µg) and a short exposure time (60 s). Examples of experiments at low temperatures under ambient and high pressures are also presented.

Notes: Abstract. The Fermi surface (FS) shape of the organic superconductor (MDT-TSF)(AuI2)0.436 with an incommensurate anion structure (MDT-TSF: methylenedithio-tetraselenafulvalene) has been investigated by means of the optical reflectance spectra and angular-dependent magnetoresistance oscillations (AMRO). The difference of the plasma frequencies between the interstack and the intrastack directions indicates that the overall band structure has small anisotropy ( $\omega_{p,\perp} / \omega_{p,\parallel} \approx 0.62$ ). The observation of the AMRO shows the presence of a small closed orbit, which can be assigned to the overlapped area of the large FS. This demonstrates that the incommensurate anion potential is crucial to remove the degeneracy of the energy bands on the zone boundary. The magnetoresistance peak in the fields applied within the conducting layers shows an unusually large interlayer transfer integral ( $t_{\perp} \approx 1$ meV) among organic superconductors.

Notes: Single crystals of AlMgB 〈sub〉14〈/sub〉 and AlMgB 〈sub〉22〈/sub〉 were grown from a high-temperature aluminum metal flux in an Ar atmosphere. The optimum conditions for growing AlMgB 〈sub〉22〈/sub〉 and AlMgB 〈sub〉14〈/sub〉 were established using the starting mixtures of B/Mg=0.5-1.0 and B/Mg=2.0-6.0. The AlMgB 〈sub〉14〈/sub〉 and AlMgB 〈sub〉22〈/sub〉 crystals obtained have well-developed {001} and {100} faces, and were black with a metallic luster. The maximum dimensions of these crystals were about 5.2 mm and 4.6 mm, respectively. The values of micro-Vickers hardness of the AlMgB 〈sub〉14〈/sub〉 and AlMgB 〈sub〉22〈/sub〉 crystals are in the ranges of 23.9±0.6-27.6±0.6 GPa. The oxidation process of AlMgB 〈sub〉14〈/sub〉 and AlMgB 〈sub〉22〈/sub〉 crystals were studied up to 1473 K by TG-DTA method. The susceptibility of AlMgB14 with an increase at low temperatures does not show any particular features, being indicative of a paramagnetic contribution, which is likely due to impurities. The susceptibility of the AlMgB 〈sub〉22〈/sub〉 sample shows no apparentcontribution from impurities and also does not have any anomalous behavior