79 research outputs found
High Speed And Large Capacity Compressor-Driving Turbines For Chemical Plants
LecturePg. 59-69.This paper gives a brief description of compressor-driving steam turbines for use in chemical plants. Turbines used for ethylene plants, ammonia plants and LNG plants, in particular, are large-capacity, high-speed variable-speed steam turbines. Their present state and the state of their development are described. Rotor dynamics technique which is the basic design technique for the attainment of their stable operation and blade design and manufacturing techniques are described in detail. Further, the construction of each component part is described in full
Model for the Substrate Hole Current Based on Thermionic Hole Emission from the Anode during Fowlar-Nordheim Electron-Tunneling in N-Channel Metal-Oxide-Semiconductor Field-Effect Transistors
Post-Fontan care based on hemodynamic characteristics, with special reference to the central venous pressure.
Changes in the hemodynamics of six patients having received Fontan-like operations were closely observed during the first 48 h after the operation. Catheterization studies and simultaneous angiocardiography were also performed before and after the operation. Hemodynamic derangement was particularly severe during the first 24 h postoperatively as indicated by a low cardiac output of less than 2.01/min/m2, which persisted in spite of very high central venous pressure. Furthermore, the central venous pressure needed to re-establish the circulation soon after the Fontan procedure significantly correlated with the angiocardiographically assessed preoperative size of distal pulmonary arteries. Accordingly, the preoperative evaluation of the distal pulmonary arterial size is very important, that provides a good guide-line for the degree of circulatory volume expansion necessary to elevate the central venous pressure and to sustain the circulation in the early postoperative period.</p
Angiocardiographic quantitative evaluation of double-outlet right ventricle: special reference to the morphology of the common outflow tract.
Geometrical measurements of angiocardiograms of the common outflow tract (COT) of 13 patients were made to determine in which cases internal conduit repair was feasible, and under which conditions a patch enlargement of the COT was indicated. In the pulmonary stenosis (PS) group, the area of the narrowest cross-section of the COT was significantly smaller than that in the pulmonary hypertension (PH) group (p less than 0.025). In the PS group, the area was rarely sufficient to be shared by systemic and pulmonary circulation. Therefore, stenosis in the outflow tract to the pulmonary artery will occur if the intraventricular tunnel technique is applied, without patch enlargement of this portion, to patients with PS. On the contrary, the cross-sectional areas of the COT and pulmonary arteries were significantly larger in the PH group than in the PS group. Accordingly, the intracardiac conduit operation may be possible in such patients without a patch enlargement, even in young patients if other intracardiac conditions allow. Preoperative angiocardiographic evaluation of the COT is helpful in preoperatively selecting the proper operative procedure for this anomaly.</p
Hemodynamic Performance of the Biventricular Bypass System Operated in an Independent Variable Rate Mode
The present study was undertaken to determine whether a biventricular bypass system operated in an independent variable rate (VR) mode can maintain the entire circulation. Two pusher-plate pumps which incorporated the Hall effect position sensors were used to bypass the right and left ventricles in 10 sheep under fibrillation. The flow distributions of the pump output to the carotid and renal arteries were investigated every 6 h using ultrasonic blood flow meters for 24 h in 5 animals, and the controllability of the VR mode was evaluated in 5 long-term experiments. The carotid artery flow ratio to the pump output decreased significantly from 4.7 +/- 0.8% before the bypass to 2.7 +/- 0.9% after 24 h. However, the renal artery flow ratio did not change throughout the experiments. In the long-term experiments, the animals were kept alive from 3 to 48 days (mean 15.6 days). The mean pump output had been maintained at more than 90 ml/min/kg for the first 7 days. After the surgery, the pump driving conditions were not readjusted in any experiment. The results indicate that the biventricular bypass system operated in the independent VR mode automatically maintains the entire circulation at a satisfactory level.</p
Enantioselective Peptide Synthesis by Using the Optically Active Polymer Containing the 1-Benzyl-3-Hydroxy-5-Isobutyl-Hydantoin Structure
The polymer containing the 1-benzyl-3-hydroxyhydantoin structure was prepared from styrene and 1-chloromethylhydantotin in order to achieve not only the act as acyl activating polymeric ester but the selective reaction using the D, L-amino acid seter. For the enantioselective peptide senthesis, the 1-benzyl-3-hydroxyhydantoin as a model compound and the 1-bernzyl-3-hydroxyhydantoin type polymer were allowed to act by two methods-the active ester method and the additive method using N, N\u27-dicyclohexylcarbodiimide (DCC). Optical yield was appreciated in 45%
Prognostic significance of cribriform adenocarcinoma of the lung: validation analysis of 1,057 Japanese patients with resected lung adenocarcinoma and a review of the literature
Background: Cribriform-predominant adenocarcinoma of the lung (Cribri-ADC) is a recently described tumor growth pattern. However, its prognostic impact has not been clearly determined. We analyzed the data of a series of 1, 057 Japanese patients with resected lung adenocarcinoma to identify the clinical significance of Cribri-ADC. Methods: Cribriform pattern (Cribri-p) is defined as invasive back-to-back fused tumor glands with poorly formed glandular spaces or invasive tumor nests comprising tumors cells that produced glandular lumina. We investigated the correlations of Cribri-p and Cribri-ADC with clinicopathological factors as well as disease-free survival (DFS) and overall survival (OS). Results: Cribri-p was present in 217 patients (20.5%) and Cribri-ADC was determined in 25 patients (2.4%). Cribri-p was associated with larger tumor size, pleural invasion, vascular invasion, lymphatic invasion, and spreading through air spaces (STAS) (all, P<0.0001). Cribri-ADC was associated with younger age (P=0.019), vascular invasion (P=0.0025), STAS (P<0.0001), and ALK rearrangement (P=0.012). The DFS curve of patients with Cribri-ADC was identical to that of patients with solid adenocarcinoma; however, the OS curve was located between that of patients with papillary and acinar adenocarcinoma. Of the 10 patients who had tumor recurrences, eight had EGFR mutations or ALK rearrangement, six of whom achieved relatively long survival (median, 64.6, range, 37.4–113 months) following treatment with tyrosine kinase inhibitors (TKIs). In multivariate analysis, Cribri-ADC was not an independent prognostic factor of either recurrence or death. Conclusions: Cribri-ADC is associated with a higher risk of recurrence; however, most patients can be successfully treated with TKIs
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