Cutting characteristics of PVD-coated tools deposited by filtered arc deposition (FAD) method

The cutting characteristics of novel physical vapor deposition (PVD)-coated tools deposited using filtered arc deposition (FAD) method are investigated. The TiCN-coated films are extremely smooth without any droplets. They exhibit superior hardness and adherence and a favorable cutting performance for the high-speed milling of a prehardened stainless steel. The availability of a newly proposed VN film is also examined. Owing to the good lubrication and tribological properties of the VN coating film, the lower cutting force, flank wear with, and cutting temperature than those of the TiN-coated tool are obtained in milling of the prehardened steel.     

Estimation of respiratory muscle endurance using an inspiratory threshold loading device in patients with chronic pulmonary emphysema and in elderly subjects

We studied respiratory muscle endurance with an inspiratory threshold loading (ITL) device using Martyn's method (2-min incremental loading test) in 9 patients with chronic pulmonary emphysema (CPE patients) and in 9 elderly subjects with no lung disease (NE subjects), and their endurance was compared with that of 9 normal young subjects (NY subjects). In 11 cases (8 CPE patients and 3 NE subjects) a treadmill exercise test was performed and cardiopulmonary parameters obtained from the ITL and treadmill tests were compared. The maximum weight tolerated for 2 minutes (Wmax) and the mean peak inspiratory mouth pressure/maximum inspiratory mouth pressure ratio at the maximum load (Ppk/MIP at Max Load) were used as indices of respiratory muscle endurance. CPE patients had significantly decreased Wmax compared with those of NE and NY subjects. Wmax in all cases positively correlated with Ppk/MIP at Max Load, and endurance time of both the ITL and treadmill tests. During both tests, SaO2 significantly decreased, and heart rate and mean blood pressure significantly increased. There was less change in SaO2 and heart rate during the ITL test than during the treadmill test, and neither arrhythmias nor ST changes on ECG were observed during the ITL test. These results indicate that the ITL test can be easily and safely employed in CPE patients and elderly subjects to estimate respiratory muscle endurance.     

Equivocal Colonic Carcinogenicity of Aloe arborescens Miller var. natalensis Berger at High‐Dose Level in a Wistar Hannover Rat 2‐y Study

ABSTRACT: A 2‐y carcinogenicity study of Aloe, Aloe arborescens Miller var. natalensis Berger, a food additive, was conducted for assessment of toxicity and carcinogenic potential in the diet at doses of 4% or 0.8% in groups of male and female Wistar Hannover rats. Both sexes receiving 4% showed diarrhea, with loss of body weight gain. The survival rate in the 4% female group was significantly increased compared with control females after 2 y. Hematological and biochemical examination showed increase of RBC, Hb, and Alb in the 4% males. The cause of these increases could conceivably have been dehydration through diarrhea. AST and Na were significantly decreased in the males receiving 4%, and Cl was significantly decreased in both 4% and 0.8% males. A/G was significantly increased in the 4% females, and Cl was significantly decreased (0.8%) in the female group. Histopathologically, both sexes receiving 4% showed severe sinus dilatation of ileocecal lymph nodes, and yellowish pigmentation of ileocecal lymph nodes and renal tubules. Adenomas or adenocarcinomas in the cecum, colon, and rectum were observed in 4% males but not in the 0.8% and control male groups. Similarly, in females, adenomas in the colon were also observed in the 4% but not 0.8% and control groups. In conclusion, Aloe, used as a food additive, exerted equivocal carcinogenic potential at 4% high‐dose level on colon in the 2‐y carcinogenicity study in rats. Aloe is not carcinogenic at nontoxic‐dose levels and that carcinogenic potential in at 4% high‐dose level on colon is probably due to irritation of the intestinal tract by diarrhea.     

Braess-like paradoxes in distributed computer systems

We consider optimal distributed decisions in distributed computer systems. We identify a Braess like paradox in which adding capacity to the system may degrade the performance of all users. Unlike the original Braess paradox, we show that this behavior occurs only in the case of finitely many users and not in the case of infinite number of users     

Materials design for industrial forming process in high-strain-rate superplastic Al-Si alloy

The optimum materials design in microstructural control could be developed for the high-strain-rate superplastic materials in the industrial scale. In the present work, it is reported that the high-performance-engine pistons with near-net-shape can be fabricated by the superplastic forging technology in the high-strain-rate superplastic PM Al-Si based alloy, which is produced by using this optimum materials design. Received: 8 February 2000 / Reviewed and accepted: 13 September 2000     

Right ventricular strain and volume analyses through deep learning-based fully automatic segmentation based on radial long-axis reconstruction of short-axis cine magnetic resonance images

Magnetic Resonance Materials in Physics, Biology and Medicine - We propose a deep learning-based fully automatic right ventricle (RV) segmentation technique that targets radially reconstructed...     

Selective photo-oxidation of various hydrocarbons in the liquid phase over V2O5/Al2O3

More than 0.22 mmol of isolated VO₄ species of V₂O₅/Al₂O₃ exhibited the highest evolution of the partial oxidation products (alcohol and ketone) in the oxidation of cyclohexane and cyclopentane. The conversion of cyclohexane and the selectivity of the partial oxidation products were achieved to be 0.49% and 85% over 0.8 g of 3.5 wt.% V₂O₅/Al₂O₃, respectively, where the K/A ratio was 6.2. In addition, V₂O₅/Al₂O₃ can selectively oxidize various hydrocarbons in the liquid phase by the one-step oxygen atom insertion to CH bond. The order of priority was tertiary carbon > secondary carbon > primary carbon > benzene ring.     

Condensation experiments for counter-current flow limitation in an inverted U-tube

In this study, we measured counter-current flow limitation (CCFL) characteristics in an inverted U-tube (18.4 mm diameter and 1.0 m straight-part length) simulating steam generator (SG) U-tubes under conditions of steam condensation at pressures of 0.1–0.14 MPa. Differential pressure ΔP between the top of the inverted U-tube and the lower tank was measured, and the flow patterns wave estimated by comparing the waveforms of ΔP with those in air–water experiments. As a result, we classified the flow patterns under CCFL conditions into CCFL-P, CCFL-L and CCFL-T. The falling water flow rate under CCFL conditions slightly increased as the pressure increased and the cooling water temperature decreased (subcooling of cooling water increased). In the case of CCFL-L, CCFL characteristics in the inverted U-tube were between those in air–water and saturated steam–water experiments at 0.1 MPa. Furthermore, we derived a Wallis type CCFL correlation and its uncertainty from CCFL data, including previously measured data, i.e., J*^1/2_G + 0.88J_L*^1/2 = 0.76 ± 0.05.     

Synthesis and biological activities of optically active 6-[3-(3,4-dimethoxybenzylamino)-2-hydroxypropoxy]-2(1H)-quinolinone (OPC-18790)

The enantiomers of 6-[3-(3,4-dimethoxybenzylamino)-2-hydroxypropoxy]-2(1H)-quinolinon e (OPC-18790), a novel cardiotonic agent, were synthesized and evaluated for positive inotropic activity. The key intermediates, 2,3-epoxypropoxy derivatives, were obtained by the alkylation of 6-hydroxy-2(1H)-quinolinone with optically active epichlorohydrin and subsequent ring closure. In an in vitro study, the (R)-(+)-isomer was about 10-fold more potent than the (S)-(-)-isomer.