Texture Development in Barium Titanate and PMN–PT Using Hexabarium 17-Titanate Heterotemplates

Bulk BaTiO₃ ceramics with 〈111〉-texture have been prepared by the modified templated grain growth method, using platelike Ba₆Ti₁₇O₄₀ particles as templates, and the mechanism of texture development is examined. The Ba₆Ti₁₇O₄₀ particles induce the abnormal growth of BaTiO₃ grains, and a structure similarity between {001} of Ba₆Ti₁₇O₄₀ and {111} of BaTiO₃ gives 〈111〉-texture to abnormally grown BaTiO₃ grains. Thus, the 〈111〉-texture develops in the BaTiO₃ matrix. The use of platelike Ba₆Ti₁₇O₄₀ particles has been extended to a 0.65Pb(Mg_1/3Nb_2/3)O₃–0.35PbTiO₃ matrix, but the matrix phase is decomposed by extensive chemical reactions between the matrix and template phases.     

Color functional images of the cerebral blood flow

Functional gamma imaging, in color, was established for regional cerebral blood flow (rCBF) using 133Xe. During 10 min after intracarotid injection of 133Xe in saline, 60 picture frames of the 133Xe clearance curve for the entire hemisphere were obtained. After nine-point smoothing, the rCBF for each of the 4,096 picture elements was calculated by two methods: the half-time method and the height-over-area method. Both the 133Xe clearance half-times and the calculated CBF values were displayed, using 13 steps of color, as functional CBF images of the brain. Images of peak count and total count were also displayed on the same frame of the color television. Forty-six studies, performed on 37 patients with various cerebral disorders, were divided into two types: diffuse and focal. In the diffuse type, a decrease in CBF was noted in cases of normal-pressure hydrocephalus; successful ventriculoperitoneal shunt operations were followed by recovery of CBF. Occlusion of the middle cerebral artery showed up as a wedge-shaped area of decreased CBF, even when the conventional brain scan looked normal. Increased perfusion to a tumor was frequently associated with decreased CBF in the rest of the lateral hemisphere; such a decrease could be improved by surgical removal of the tumor.     

Low-power on-chip supply voltage conversion scheme forultrahigh-density DRAMs

In order to achieve 3.3-V 1-Gb DRAM and beyond, a new on-chip supply voltage conversion scheme that converts 3.3-V external supply voltage, V_ext, to lowered 1.5-V internal supply voltage, V_ent, without any power loss within the voltage converter is proposed. This scheme connects two identical DRAM circuits in series between V_ixt and V_ss. By operation of two DRAM circuits with the same clock timing, the voltage between two DRAMs, V_int, is automatically fixed to 1/2V_ext. Therefore, each upper and lower DRAM circuit can operate at lowered 1/2V_ext without use of the conventional voltage converter. This scheme was successfully verified by an experimental system using 4-Mb DRAMs. Utilizing the proposed scheme, power dissipation was reduced by as much as 50% and stable operation was achieved without access speed penalty     

Paroxysmal nocturnal hemoglobinuria with myelofibrosis: progression to acute myeloblastic leukemia

Buccal hairy leucoplakia is associated with Epstein-Barr and HIV virus infections. The main symptom is the characteristic hairy lesion on side parts of the tongue without any other clinical sign. Histologically, there are hyperkeratosis, vacuolar degeneration, and presence of Candida, but no inflammatory infiltration. Antiviral drugs led to the regression of lesions, but there is a trend to relapse when treatment is interrupted.     

A successful treatment of infective mediastinitis with chylomediastinum after the closure of atrial septal defect (ASD)

A 48-year-old woman underwent the closure of ASD. She developed infective mediastinitis with chylomediastinum 14 days after the operation. She received mediastinal debridement and continuous lavage. Two days following mediastinal irrigation, omentopexy and delayed closure of the sternum resulted in satisfactory outcome.     

Measurement of nitric oxide in the rat cerebral cortex during hypercapnoea

Changes in nitric oxide (NO) concentration and cerebral blood flow (CBF) in the parietal cortex during hypercapnoea were investigated in anaesthetized rats, using a NO-selective electrode and laser Doppler flowmetry. When hypercapnoea was induced by inhalation of 5% CO2 for 10 min, both the NO concentration and CBF increased. After administration of 7-nitroindazole, a neuronal NO synthase (nNOS) inhibitor, both the basal NO and CBF decreased, and responses to hypercapnoea were also significantly suppressed by 70.1% and 73.2%, respectively, compared with the control state. These results suggest that NO derived from nNOS is involved not only in maintaining resting cerebral circulation but also in regulating CBF response during hypercapnoea.     

Photoluminescence in Polyamide/mica and Polyethylene/ MgO Nanocomposites Induced by Ultraviolet Photons

Nature of electronic states in the energy band is investigated by means of optical absorption and photoluminescence induced by vacuum ultraviolet photons for polyamide-6/mica and low-density polyethylene/MgO nanocomposites. The nanofiller loading does not affect the absorption spectra of polyamide samples. Contrary to this, two absorption bands are induced at around 5.0 and 6.2 eV by the nanofiller loading in polyethylene samples, but they are due to absorption by the fillers. A luminescence band is observed at around 3.0 eV in polyamide samples, whereas three luminescence bands are observed at around 4.3, 3.7, and 2.9 eV in polyethylene samples. However, for all the luminescence bands, neither emission nor excitation energies change by the addition of nanofillers. Decay profiles of all the luminescence bands are essentially unchanged by the nanofiller loading. Moreover, no new PL bands are induced in the observed wavelength range. These results indicate that localized states, at least as far as the ones that can emit luminescence photons with intensities more than the sensitivity of the present research, are not induced by the nanofiller loading.     

Multilevel cycle of anthropogenic copper

A comprehensive contemporary cycle for stocks and flows of copper is characterized and presented, incorporating information on extraction, processing, fabrication and manufacturing, use, discard, recycling, final disposal, and dissipation. The analysis is performed on an annual basis, ca. 1994, at three discrete governmental unit levels--56 countries or country groups that together comprise essentially all global anthropogenic copper stocks and flows, nine world regions, and the planet as a whole. Cycles for all of these are presented and discussed, and a "best estimate" global copper cycle is constructed to resolve aggregation discrepancies. Among the most interesting results are (1) transformation rates and recycling rates in apparently similar national economies differ by factors of two or more (country level); (2) the discard flows that have the greatest potential for copper recycling are those with low magnitude flows but high copper concentrations--electronics, electrical equipment, and vehicles (regional level); (3) worldwide, about 53% of the copper that was discarded in various forms was recovered and reused or recycled (global level); (4) the highest rate of transfer of discarded copper to repositories is into landfills, but the annual amount of copper deposited in mine tailings is nearly as high (global level); and (5) nearly 30% of copper mining occurred merely to replace copper that was discarded. The results provide a framework for similar studies of other anthropogenic resource cycles as well as a basis for supplementary studies in resource stocks, industrial resource utilization, waste management, industrial economics, and environmental impacts.