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Lead–bismuth two-phase flow in a cylindrical vessel and annulus was experimentally investigated by varying the surface wettability of the vessel wall. The test section used in this study was a cylindrical stainless vessel with/without inner sleeve to change the hydraulic diameter. Volume-averaged void fraction was measured by varying the surface wettability of the test section, which was enhanced by using a soldering flux. Measured void fraction was compared with existing two-phase flow correlations and with one-dimensional theoretical simulations assuming one-dimensional drift-flux model. From experimental results, measured distribution parameters of the lead–bismuth two-phase flow are much larger than that of ordinary two-phase flow regardless of the surface wettability. In the present work, the one-dimensional analysis was carried out for the cylindrical vessel to reproduce the distribution parameter. From the simulation results, predicted value for the cylindrical vessel showed good agreement ...

Fibronectin (FN) is thought to play an important role in various aspects of hematopoiesis through binding to very late antigen (VLA)-4 and VLA-5. Little is known, however, about the effects of FN on the proliferation of B cell progenitors. In this study, we investigated the effects of immobilized FN on the proliferation of the pre-B cell line, Nalm-6, which expresses both VLA-4 and VLA-5. Immobilized FN significantly promoted the proliferation of Nalm-6 cells through the synergistic effects of VLA-4 and VLA-5. Furthermore, FN induced the phosphorylation of mitogen-activated protein kinases (MAPKs) of Nalm-6 cells. The MAPK kinase 1 (MEK1) inhibitor, PD98059, and Src family tyrosine kinase inhibitor, herbimycin A, inhibited the FN-promoted proliferation of Nalm-6 cells. These results demonstrate that the interactions of FN and VLA-4/VLA-5 transmit the growth signals that are mediated through Src family tyrosine kinases and the MAPK cascade in Nalm-6 cells. The precise mechanism of synergistic effect of VLA-4 and VLA-5 on FN-promoted proliferation of Nalm-6 cells should be further investigated.

In relation to thermal-hydraulic design of the solid-target system of a spallation neutron source, heat transfer experiments were performed to obtain experimental data systematically on heat transfer coefficient and critical heat flux (CHF) for vertical upward and horizontal flows in thin rectangular channels simulating a coolant channel of the proposed spallation neutron source. Single phase heat transfer coefficients and CHF data for rectangular channels with 1.0mm gap (L h /D e =50.2) with mass flux of 10–7,500kg/m2-s, single phase and two phase heat transfer coefficients, onset of nucleate boiling (ONB) and CHF data for 1.5 mm gap (L h /D e =33.9) with mass flux of 10–5,000 kg/m2-s were obtained in the atmospheric pressure with inlet subcooling of 40–80 K. Finally, thermal-hydraulic correlations that could be used for design calculations were proposed based on the obtained data.

We report the case of a 52-year-old woman with hepatitis B virus (HBV) reactivation during treatment for chronic graft vs. host disease (GVHD) after peripheral bone marrow transplantation (PBSCT) to treat chronic myelocytic leukemia. She was given cyclosporine and prednisolone orally to treat chronic GVHD after PBSCT. Liver dysfunction first developed 25 months after transplantation with the appearance of hepatitis B s antigen (HBsAg), hepatitis B e antigen (HBeAg), and elevation of HBV-DNA up to 4.5 log copies/ml. Retrospective examination of her serum before PBSCT proved negative for HBsAg and HBeAg, and positive for anti-HBsAg, anti-HBeAg, anti-hepatitis B core antigen, and HBV-DNA (2.7 log copies/ml), showing that she was in a state of occult HBV infection. Nucleotide sequences of the HBV genome obtained from her serum showed no core promoter mutations at nt 1762 and 1764 and no pre-core mutation at nt 1896. Polymerase chain reaction-restriction fragment length polymorphism showed that she was infected with HBV genotype B. The administration of lamivudine, a nucleoside analog, improved her liver function and reduced HBV-DNA replication. We conclude that antiviral agents, such as lamivudine, are effective for treating hepatitis B reactivation during immunosuppressive treatment, such as for GVHD. The administration of a nucleoside analog before transplantation should also be considered in the light of HBV genotypes and mutations, even if HBsAg was negative and the viral load was low before transplantation.

The relationship between coronary stenosis and 'midband' lipoprotein, which was observed between low density lipoproteins and very low density lipoproteins by 3% polyacrylamide gel electrophoresis, was studied in patients with heterozygous familial hypercholesterolaemia (FH). The subjects were 46 patients with FH, who were evaluated by coronary angiography. The groups with and without coronary artery disease (CAD) were compared. Age, sex ratio, total cholesterol, triglyceride, HDL-cholesterol and lipoprotein(a) levels were matched in these two groups. In addition, Achilles tendon thickness and the incidence of risk factors such as diabetes mellitus, hypertension and smoking between these two groups were matched. Under these conditions, the frequency of midband was higher in the patients with CAD (20/26) than that in patients without (4/20). The results suggest that the presence of a midband among Japanese is an independent risk factor for coronary stenosis even in cases of FH who have severe hypercholesterolaemia.

The mechanism regulating lipoprotein lipase (LPL) expression in adipose tissue was examined in rats in the conditions of different calorie intakes with and without streptozotocin-induced (STZ-) diabetes. The LPL activity released from adipose tissue was greater with the higher calorie intake (20 g of normal chow diet per day) than with the lower calorie intake (13 g of normal chow diet per day), and was greater in normal rats than in STZ-diabetic rats. The LPL activity was proportional to the serum insulin level in all conditions. Dot-blot analysis showed that the amount of LPL mRNA in adipose tissue was increased by the higher calorie diet and that the increase was less in the diabetic state. Expression of mRNA was also nearly parallel with the serum insulin level. LPL activity released from the heart was not affected by either the calorie intake or the diabetic state. These results suggest that the mechanisms of LPL expression in adipose tissue and the heart are different, and that LPL expression in adipose tissue was closely dependent on the insulin level.

LDL-apheresis is introduced in many cases all over Japan. Among them, evaluation of long-term effect on ischemic heart disease (IHD) has made on 10 cases with homozygous familial hypercholesterolemia (FH) and 49 cases with heterozygous FH.As to homozygous FH, 3 patients had angina pectoris. Mean duration of treatment was 26 months (52 treatments). The changes in total cholesterol (TC) in each treatment was from 426 mg/dl to 151 mg/dl. Improvement in IHD was observed in 5 out of 10 cases.As to heterozygous FH, 17 cases had history of myocardial infarction and 12 had angina pectoris. Mean duration of treatment was 13 months (19 treatments). Mean TC was decreased from 271 mg/dl to 126 mg/dl by each treatment. Regression in Achilles tendon thickenting or skin and palpebral xanthomas was observed. Frequency of anginal attacks decreased in 8 out of 17 cases. Ischemic change in ECG were improved in 3 out of 26 cases. Coronary angiography performed with 2 to 3 years of interval in some cases revealed regression o...

SUMMARY This study deals with the establishment of a theory of backward motion of multi-articulated vehicles and their control. First, a theory of backward motion of multi-articulated vehicles was studied under geometrical motion, and verified by experiments. Then, the conditions which design specifications had to satisfy were given from controllability, and control limits from the maximum steering angle. Using the optimal control theory, the maneuverability of multi-articulated vehicles was discussed, and the difficulty of backward maneuverability with an increase in the number of articulated vehicles was shown. On the basis of these study results, the effectiveness of an auxiliary operation system was suggested.

(1979). On the Stability and Followability of the Semi-Trailer Vehicle with an Automatic Steering System. Vehicle System Dynamics: Vol. 8, No. 2-3, pp. 206-211.

In the field of vehicle handling research many and various investigations have been devoted to evaluate driver-vehicle system performance. However, no generally accepted test procedures have been evolved from the past research efforts. This paper proposes a method for evaluating objective and fundamental maneuverability of the vehicle by a simulation study of lane-change maneuvers. As the most important handling qualities of the vehicle in cruising on the roads, there could be considered three aspects; (1) keeping the vehicle with ease on the centerline of the road in fast straight running, (2) conducting lane-changing maneuvers quickly and safely and (3) making a rapid 90 degree turn smoothly at the corners. No doubt the first of them is mainly concerned with the directional stability and both the second and the third are closely related to the controllability of the vehicle. In this paper, the second aspect of vehicle handling, that is, a double lane-change maneuver is selected to evaluate the maneuverability of a motor vehicle.