Effects of Long-Time DC Bias on D2O- and D2/N2-Annealed BST Thin Films

Effects of long time dc bias on both D₂O- and D₂-annealed BST thin films were investigated by secondary ion mass spectrometry (SIMS) analysis and electrical measurements before and after bias stressing. Bias conditions were sufficient to cause the degradation of (1) subsequently-measured current density-voltage characteristics and (2) a significant positive shift of the capacitance-voltage curve along the voltage axis. This latter effect may be attributed to the asymmetric space charge distribution in the BST thin film after bias stressing or, possibly, to changes in the interface state density. No significant deuterium motion was observed in D₂O-annealed capacitors biased at an elevated temperature or in D₂/N₂-annealed capacitors biased at room temperature in high electric fields (3.5 × 10⁷ V/m) for more than 8 hours. The small values of the D_i mobility which were inferred from the SIMS results are consistent with recent data on the kinetics of deuterium incorporation in and removal from similar BST thin films.     

Antiproliferative and apoptotic effects of tocopherols and tocotrienols on normal mouse mammary epithelial cells

Studies were conducted to determine the comparative effects of tocopherols and tocotrienols on normal mammary epithelial cell growth and viability. Cells isolated from midpregnant BALB/c mice were grown within collagen gels and maintained on serum-free media. Treatment with 0–120 μM α-and γ-tocopherol had no effect, whereas 12.5–100 m μM tocotrienol-rich fraction of palm oil (TRF), 100–120 μM δ-tocopherol, 50–60 μM α-tocotrienol, and 8–14 μM γ- or δ-tocotrienol significantly inhibited cell growth in a dose-responsive manner. In acute studies, 24-h exposure to 0–250 μM α-, γ-, and δ-tocopherol had no effect, whereas similar treatment with 100–250 μM TRF, 140–250 μM α-, 25–100 μM γ- or δ-tocotrienol significantly reduced cell viability. Growth-inhibitory doses of TRF, δ-tocopherol, and a-, γ-, and δ-tocotrienol were shown to induce apoptosis in these cells, as indicated by DNA fragmentation. Results also showed that mammary epithelial cells more easily or preferentially took up tocotrienols as compared to tocopherols, suggesting that at least part of the reason tocotrienols display greater biopotency than tocopherols is because of greater cellular accumulation. In summary, these findings suggest that the highly biopotent γ- and δ-tocotrienol isoforms may play a physiological role in modulating normal mammary gland growth, function, and remodeling.     

Specific impairments in self-regulation in children exposed to alcohol prenatally

The present study utilizes a conceptual framework derived from theories of cognition to explain the pattern of behavioral and learning problems observed in subjects with fetal alcohol syndrome (FAS) and fetal alcohol effects (FAE). Based on a modern interpretation of Luria's theory of self-regulation, this study used a neuropsychological test battery to compare 10 subjects (mean age = 13 years) having FAS/FAE with 10 control subjects (mean age = 12 years and 9 months). Subjects with FAS/FAE were relatively high functioning and did not significantly differ from controls with respect to receptive vocabulary. However, those with FAS/FAE exhibited greater difficulty than controls on tasks that involved the manipulation of information and goal management in working memory (e.g., Planning, Controlled Oral Word Association, etc). Both groups performed equally well on some tasks that demanded rule learning (Delayed Response) and response inhibition (Go-No-Go). The above impairments were interpreted to be reflective of selective rather than generalized disruptions of neural networks that subserve working memory.     

The improved corrosion resistance of steel in water after abrasive blasting with alumina

Polarization resistance studies and cathodic delamination studies provide evidence that steel abrasively blasted with alumina exhibits a lower initial rate of corrosion in distilled water than similar steels blasted with steel grit or abraded with silicon carbide paper. Auger spectroscopy and electron microprobe analysis revealed the presence of significant aluminum on the surface, largely in the form of embedded particles but possibly also as a constituent of the oxide film. Non-metallic abrasive blasting may have application in the chemical modification of metal surfaces.     

Pulmonary nodules: effect of increased data sampling on detection with spiral CT and confidence in diagnosis

PURPOSE: To compare spiral computed tomography (CT) with interscan spacing of 4-5 mm versus 8-10 mm for detection rate and level of confidence in diagnosis of pulmonary nodules. MATERIALS AND METHODS: Four radiologists (two junior and two senior faculty members) retrospectively reviewed 67 spiral CT studies with one to six nodules per study. Every second image was masked, which resulted in 8-mm sections every 8 or 10 mm; then all images reconstructed every 4 or 5 mm were reviewed. Lesions were classified as definite, probable, or possible. RESULTS: Narrow interscan spacing yielded more lesions overall (583 vs 566, P < .025) and more definite lesions and fewer equivocal lesions (482 vs 431 and 101 vs 135, respectively; P < .055). The greatest effects were in the reduction of possible lesions (50 vs 88, P < .001) and in the reduction of false-positive diagnoses made by less experienced radiologists. CONCLUSION: Increased reconstruction frequency of spiral CT volume data sets improves detection of pulmonary nodules and enhances confidence in the diagnosis.     

Successful re-treatment with taxol after major hypersensitivity reactions

PURPOSE: To describe the successful re-treatment of eight patients who had major hypersensitivity reactions (HSRs) to taxol and to suggest a regimen for re-treating patients who develop major HSRs. PATIENTS AND METHODS: The treatment courses of eight patients who developed major HSRs and were rechallenged with taxol were reviewed. Patients in this report represent all patients who are known to have been rechallenged with taxol after major HSRs. RESULTS: The most common approach used to rechallenge patients consisted of premedication with multiple high doses of corticosteroids and H1- and H2-histamine antagonists followed by the initiation of the taxol infusion at a reduced rate. All patients who experienced major HSRs were rechallenged successfully. After the rechallenge, these patients received 32 additional courses of taxol without HSRs. CONCLUSION: Re-treatment with taxol after major HSRs is feasible using multiple high doses of corticosteroids and antihistamine premedications and a reduced taxol infusion rate under close supervision. This approach may represent a valid alternative to the termination of taxol; however, a prospective evaluation is required to determine the true efficacy of this approach.     

The potential for lower extremity revascularization without contrast arteriography: experience with magnetic resonance angiography

PURPOSE: We report an initial experience with 24 patients studied between March 1990 and April 1992 with magnetic resonance angiography (MRA) for lower extremity occlusive disease. METHODS: All patients underwent vascular intervention with either balloon angioplasty or bypass grafting, and in six patients this intervention was based on MRA findings alone. Eighteen patients were studied with both MRA and contrast arteriography, and there was observed agreement between the two studies in 98% of all arterial segments examined. RESULTS: Agreement between MRA and contrast arteriography was uniform for arterial segments below the inguinal ligament. Intraoperative findings and favorable early results of seven bypass grafts performed in six patients after MRA alone suggested this was a valid approach for patients at prohibitive risk of complications from contrast arteriography. CONCLUSIONS: Magnetic resonance angiography is accurate in demonstrating relevant anatomy in peripheral arterial occlusive disease and in selected patients may eliminate the need for contrast arteriography before lower extremity revascularization.