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It is known that Cu valence of cuprate superconductors govern transition temperature (Tc). For La2-xSrxCuOy, when x = 0.15, that is, Cu valence is 2.15, the highest Tc around 40K is achieved. The Cu valence is determined both by strontium and oxygen content. So far, coulometry and iodometry have been used for determining oxygen content. However, these chemical analyses usually require experience. The purpose of this research is to develop a novel measuring method of oxygen content in cuprate superconductors with a developed dissolved oxygen sensor. Signal received from the sensor is sent to PC automatically without any external power supply. Oxygen content obtained with the sensor was newly compared with iodometry. It was found that this method is reliable enough to determine oxygen content in La2-xSrxCuOy, and is called dissolved oxygen method.

The highly sensitive Raman cell based on the hollow optical fiber that is suitable for the real-time breath analysis is reported. Hollow optical fiber with inner coating of silver is used as a gas cell and a Stokes light collector. A very small cell whose volume is only 0.4 ml or less enables fast response and real-time measurement of trace gases. To increase the sensitivity the cell is arranged in a cavity which includes of a long-pass filter and a high reflective mirror. The sensitivity of the cavity cell is more than two times higher than that of the cell without cavity.

In order to investigate physical conditions of ionized gas in galaxies, as well as its kinematics, we have developed the Kyoto tridimensional spectrograph II. It is a multimode optical instrument, including integral field spectrograph (IFS) and Fabry-Perot imager modes. We have designed it compact so that we can mount it on 2 m class telescopes as well as on the 8.2 m Subaru telescope. Special care was taken to obtain high-quality calibrations in the IFS mode. In order to remove the chromatic aberration of micropupil images produced by a lenslet array, we have introduced a corrector lens system behind the lenslet array. The internal calibration system simulates the telescope optics so that the system provides micropupil images identical to those produced by the telescope. The rigidness of the instrument provides the positional stability of micropupil images. We have succeeded in test observations of all the modes on Subaru and the University of Hawaii 88 in (UH88) telescopes and have verified the performance of the instrument. This includes the instrument efficiencies as well as the effective sky background subtraction and the minimization of crosstalk effects in the IFS mode. In the IFS mode a spatial resolution of 0.4? was obtained in good seeing conditions. Each of 37 × 37 lenslets subtends 0.1? in Subaru's case. This samples the image size well. A wider field of view is emphasized in the case of UH88.

Investigating the possibility of magnetic resonance angiography (MRA) to visualize the Adamkiewicz artery of as a preoperative study of thoracic aortic aneurysms.

Background: Preservation of the annulo-papillary muscle continuity in mitral valve replacement is important. Even in patients who require excision of the mitral apparatus, the continuity can be restored. However, there is no guide to the proper length for the resuspension. Methods: In 57 normal cadaveric hearts, the distance from the tip of the papillary muscle to its corresponding mitral anulus was directly measured. Results: The distance from the tip of the anterolateral papillary muscle to the left trigone (10-o'clock position: D10) and to the point between the anterior and the middle scallops of the mural leaflet (8-o'clock position: D8) was 23.5 +/- 3.7 mm and 23.2 +/- 3.6 mm, respectively. The distance from the tip of the posteromedial papillary muscle to the right trigone (2-o'clock position: D2) and to the point between the middle and the posterior scallops of the mural leaflet (4-o'clock position: D4) was 23.5 +/- 4.0 mm and 23.5 +/- 3.9 mm, respectively. There was no statistically significant difference among the 4 distances (P = .96). Each distance was significantly longer than the corresponding chordae tendineae (D10 vs the anterior main chorda: 17.2 +/- 3.9 mm, D8 vs the anterior cleft chorda: 14.5 +/- 3.2 mm, D2 vs the posterior main chorda: 17.9 +/- 4.3 mm, and D4 vs the posterior cleft chorda: 14.9 +/- 3.2 mm, respectively; P = .0001). The mean distance had a significant correlation with the mitral annular diameter (r = 0.31, P = .019). Conclusions: In normal hearts, the annulo-papillary muscle distances of the mitral apparatus are similar in 2-, 4-, 8-, and 10-o'clock positions and correlate with the mitral annular diameter. (J Thorac Cardiovasc Surg 1999;118:636-41)

Congenital bicuspid aortic valve is a relatively rare malformation. It is reported that the presence of this anomaly predisposes the patient to development of true aortic aneurysms or dissecting aortic aneurysms. Between 1981 and August 1997, 25 patients with an aneurysm of the thoracic aorta associated with congenital bicuspid aortic valve underwent surgical treatment at the authors' institution. There were 20 males and five females. The age of the patients ranged from 27 to 74 years (mean 53 years). There were 18 patients with true ascending aortic aneurysms (of which 10 presented with annulo-aortic ectasia) and seven with dissecting aortic aneurysms (four with DeBakey type I dissection, two with type II and one with type IIIb). These 25 patients constituted 2.6% (25/973) of all cases of surgical operations for aneurysms in the thoracic aorta. Aortic valve dysfunction was noted in 20 patients. The authors performed a valved conduit operation in nine patients, aortic valve replacement and wrapping of the ascending aorta in six, graft replacement of the ascending aorta in five, graft replacement of the ascending aorta and aortic arch in four, and graft replacement of the descending aorta in one. No hospital deaths occurred in the authors' patients. Pathological examination of surgical specimens of the aortic wall showed cystic medial necrosis in 11 patients and mucoid degeneration in nine. In patients with congenital bicuspid aortic valve, attention should be paid to aneurysmal dilatation and aortic dissection as complications in addition to valve dysfunction.

Abstract: Linear system analysis was applied to calcium channel gating on the biological membrane. The conformational changes of calcium channel gating were expressed by an allosteric enzyme model composed of four subunits with corresponding voltage sensor molecules. The rate constants for the channel states transitions were obtained from reported biological experiments and simulation. The linear system analysis disclosed that the system is unstable and uncontrollable. Combinations of each input site and output of the channel gating state for the impulse responses and the singular values of the system showed that the potency of any particular input site for evoking impulse responses at any particular channel state and singular value is not equivalent among the channel states but favor for large numbers of voltage sensors and open channel states. Allosteric effects for modifying the concerted cooperative properties of the calcium channel have a significant influence on the singular values of the system. System optimization improved the system properties of the calcium channel and will be available for evaluating the economical channel gating of the biological membrane and artificial membrane.

The purpose of this study was to demonstrate early and long-term results of surgery for thoracic aortic aneurysm in patients over 70 years of age compared with those of patients under 70 years and to clarify the clinical problems peculiar to this subset of patients.

Between November 1966 and December 1990, 511 pediatric patients with tetralogy of Fallot underwent corrective operation at Tenri Hospital. There were 78 patients with subarterial ventricular septal defect. Mean age at repair was 5.6+/-3.3 years. The method of right ventricular outflow tract reconstruction was simple infundibulectomy in 14 patients, right ventricular outflow patch in 36, and transannular patch in 28. There were 7 (9.0%) early deaths as a result of low cardiac output syndrome and acute renal failure. The pressure ratio of the right ventricle to the left ventricle was 0.62+/-0.18 during the early postoperative catheterization. Follow-up was achieved for 442.6 patient-years and ranged from 0.5 to 27 years, with an average of 8.5+/-6.7 years. There were three late deaths (2 cardiac and 1 noncardiac). Actuarial survival was 94.8%+/-4.0% at 20 years. Catheterization during late follow-up (6.8+/-4.7 years after repair) was done in 53 patients and the pressure ratio of the right ventricle to the left ventricle was 0.48+/-0.21. Fifteen patients underwent subsequent operation because of residual lesions, including ventricular septal defect in four patients, pulmonary stenosis in nine, combined ventricular septal defect and pulmonary stenosis in one, and pulmonary regurgitation in one, with no mortality. Actuarial rate of freedom from reoperation was 71.1%+/-8.0% at 10 years and 58.8%+/-16.8% at 20 years. Patients with tetralogy and subarterial ventricular septal defect were more likely to have the development of residual obstruction at the level of the pulmonary valve anulus after repair than were those with tetralogy and perimembranous ventricular septal defect.

We made a detailed source analysis of the magnetic field responses that were elicited in the human brain by different monosyllabic speech sounds, including vowel, plosive, fricative, and nasal speech. Recordings of the magnetic field responses from a lateral area of the left hemisphere of human subjects were made using a multichannel SQUID magnetometer, having 37 field-sensing coils. A single source of the equivalent current dipole of the field was estimated from the spatial distribution of the evoked responses. The estimated sources of an N1m wave occurring at about 100 ms after the stimulus onset of different monosyllables were located close to each other within a 10-mm-sided cube in the three-dimensional space of the brain. Those sources registered on the magnetic resonance images indicated a restricted area in the auditory cortex, including Heschl's gyri in the superior temporal plane. In the spatiotemporal domain the sources exhibited apparent movements, among which anterior shift with latency increase on the anteroposterior axis and inferior shift on the inferosuperior axis were common in the responses to all monosyllables. However, selective movements that depended on the type of consonants were observed on the mediolateral axis; the sources of plosive and fricative responses shifted laterally with latency increase, but the source of the vowel response shifted medially. These spatiotemporal movements of the sources are discussed in terms of dynamic excitation of the cortical neurons in multiple areas of the human auditory cortex.

Replacement of the entire descending aorta or of the thoracoabdominal aorta still has a significant risk for postoperative paraplegia. Surgical strategies using a deep hypothermia to protect the spinal cord or viscera are discussed.

Long-term results of patch repair in patients with a saccular aneurysm of the aortic arch were investigated.

This study reports surgical experience of 72 cases of aortic dissection with intimal tear in the transverse aortic arch.

Perioperative factors affecting the outcomes of postoperative brain function in patients with thoracic aortic aneurysm were demonstrated.

Streptococcus milleri were isolated from at least one of seven defined oral sites from all 13 children examined. The streptococci were detected in high frequencies and proportions in both subgingival and approximal plaque. Isolation from softened dentine was infrequent but in relatively high proportions when detected. Ninety-nine pure isolates were finally cloned on MC and blood agar plates. All but one of the rough colony-forming strains on blood agar plates (51 strains) showed spontaneous cellular aggregation in BHI broth. Most strains were non-haemolytic (61), and belonged to API taxon S. milleri II (88) and to biotypes la (31) or IId (44). Two-thirds of the isolates were classified into one of six serotypes, c (1), g (10), h (8), i (43), j (2) and k (1), but only one-tenth belonged to Lancefield groups F (untypeable; nine) or G (serotype k; one). Strains isolated from subgingival plaque were biologically and serologically most variable, five serotypes and seven biotypes being detected therein. Multiple serotypes and biotypes were detected in the mouths of five and seven subjects, respectively. However, five subjects harboured strains of a single serotype and four of a single biotype in more than three oral sites; from three of them all isolates were both serologically and biologically distinct. Serological and physiological characteristics of the isolates from various oral sites of respective subjects were generally small in variation and very particular to individual subjects.

The subjects consisted of one patient with chronic type A and three patients with chronic type B aortic dissection, who underwent replacement of an aorta obliterating distal false lumen. After the repair, the formation of two layers was detected by direct scanning echocardiography within the false lumen even during heparinization. In all cases, postoperative computed tomography confirmed complete thrombosis of the false lumen. The formation of two layers was considered to be a reliable predictor of late thrombosis.

Resistance spot welds (RSW) in transformation-induced plasticity (TRIP) steel sheets were locally postweld heat treated by applying a second pulse of current in the welding schedule. The evolution of the fusion zone (FZ) microstructure by optical and scanning electron microscopy, microhardness, and standardized quasi-static lap-shear tensile testing was investigated for all the pulse current conditions. The most important result of this study is that improved mechanical properties with desirable pullout failure mode is accomplished when the FZ microstructure consists of a recrystallized structure of martensite, which was achieved in the medium level of the second pulse current postweld heat treatment. Even though a considerable reduction in FZ hardness was observed at the lowest value of the second pulse current due to the presence of plate-like ferrite and tempered martensite structure, the failure mode and load-bearing capacity of the weldment was not improved significantly. At higher current levels of the second pulse condition, remelting occurred with consequent formation of a new weld nugget comprising columnar structure but larger nugget size giving mixed failure modes. The fusion zone microstructures and microhardness results correlated well with the simulated welding thermal history of the postweld local heat treatments. [ABSTRACT FROM AUTHOR]

The off state current for polysilicon thin-film transistors for pixels in LCDs has been successfully reduced by introducing a polysilicon buffer layer between a polysilicon active layer fabricated by solid-phase-crystallisation (SPC) and a fused quartz substrate. Off-state current of less than 1 pA under Vgs = –25 V at Vds = 3 V was obtained for n-channel single-gate coplanar transistors using the buffer layer (400 Å).