Analytical studies of four-inch pipe whip tests under BWR LOCA conditions

The purpose of pipe rupture studies in JAERI is to perform model tests on pipe whip, restraint behavior, jet impingement and jet thrust force, and to establish a computational method for analyzing these phenomena. This report presents the analytical results of 4-inch pipe whip tests under BWR LOCA conditions.Dynamic response analyses were performed using the general-purpose finite element program ADINA. The test pipe was modelled by straight beam elements and the four restraints were modelled by a single truss element. The analytical results were compared with the experimental results. Impact time and maximum total restraint force showed good agreement with experimental results. On the other hand, pipe strain and pipe deflection could not be predicted so well. The reason for this is that the sliding of the restraint during the pipe whip movement cannot be considered in the analyses.     

Theranostic Agent Combining Fullerene Nanocrystals and Gold Nanoparticles for Photoacoustic Imaging and Photothermal Therapy

Developing photoactivatable theranostic platforms with integrated functionalities of biocompatibility, targeting, imaging contrast, and therapy is a promising approach for cancer diagnosis and therapy. Here, we report a theranostic agent based on a hybrid nanoparticle comprising fullerene nanocrystals and gold nanoparticles (FGNPs) for photoacoustic imaging and photothermal therapy. Compared to gold nanoparticles and fullerene crystals, FGNPs exhibited stronger photoacoustic signals and photothermal heating characteristics by irradiating light with an optimal wavelength. Our studies demonstrated that FGNPs could kill cancer cells due to their photothermal heating characteristics in vitro. Moreover, FGNPs that are accumulated in tumor tissue via the enhanced permeation and retention effect can visualize tumor tissue due to their photoacoustic signal in tumor xenograft model mice. The theranostic agent with FGNPs shows promise for cancer therapy.     

Autoantibodies detectable in the sera of silicosis patients. The relationship between the anti-topoisomerase I antibody response and HLA-DQB1*0402 allele in Japanese silicosis patients

Eighty-one Japanese silicosis patients and 66 healthy volunteers were analyzed for autoantibodies by ELISA, and HLA-genotyping using the PCR-RFLP method was performed. Anti-topoisomerase I (anti-topo I) autoantibodies were detected in seven patients without any clinical features of autoimmune diseases such as progressive systemic sclerosis (PSS), although anti-topo I have been mostly reported in PSS patients. Antibodies directed to RNP, ssDNA, dsDNA and cent-B were not detected among the anti-topo I positive patients. The indirect immunofluorescent staining pattern of Hep-2 cells with the sera of anti-topo I positive silicosis patients demonstrated the typical mode of anti-topo I autoantibodies observed in the patients with PSS. The allelic frequency of HLA-DQB1*0402 was significantly higher in anti-topo I positive patients (28.6%) than in anti-topo I negative patients (1.5%, P < 0.001) or healthy controls (0.8%, P<0.001). HLA-DQB1*0301, DQB1*0601 and DPB1*1801 alleles were more frequently detected in anti-topo I positive patients than in the patients without anti-topo I or in healthy volunteers, but no significant difference was observed. DQB1 allele is associated with the induction of anti-topo I autoantibodies in Japanese silicosis patients, but the allele is not the same as in Caucasian PSS patients. Another allele (DQB1*0402) plays an important role in Japanese silicosis patients. The most important factor to induce anti-topo I autoantibodies seems not to be the type of alleles themselves, but the position of some specific amino acid residues in the DQ beta first domain. These findings will be useful for preventing occupational autoimmune diseases.     

Combining beta-core fragment and total oestriol measurements to test for Down syndrome pregnancies

Recent articles by Cuckle et al., Canick et al., and Isozaki et al. have evaluated urine beta-core fragment as a screening test for Down syndrome in second-trimester pregnancies. They found over four-fold elevation of beta-core fragment levels in Down syndrome pregnancies, and between 62 and 88 per cent detection of this trisomy at a 5 per cent false-positive rate. Urine beta-core fragment may be a superior screening test for Down syndrome pregnancies. In the present study, urinary total oestriol has been evaluated as a marker to use in combination with beta-core fragment in screening for Down syndrome pregnancies. The two markers were evaluated separately in relation to the urine creatinine concentration. To amplify screening performance, we evaluated the ratio of beta-core fragment to total oestriol levels (creatinine-independent). beta-core fragment and total oestriol levels were determined (normalized to creatinine, ng/mg creatinine) in urine samples from 480 unaffected and 12 Down syndrome pregnancies, collected consecutively at a single prenatal diagnosis centre. The median beta-core fragment level in Down syndrome cases was 4.5 MOM. Fifty-eight per cent of Down syndrome cases had beta-core fragment levels exceeding the 95th centile of unaffected pregnancies. The median total oestriol level in Down syndrome cases was 0.33 MOM. Forty-two per cent of Down syndrome cases had total oestriol levels exceeding the 95th centile of unaffected pregnancies. We investigated the ratio of the two determinants (beta-core fragment, ng/ml divided by total oestriol, ng/ml) in our sample set. The median beta-core fragment:total oestriol ratio in Down syndrome cases was 13 MOM. Seventy-five per cent of Down syndrome cases had a ratio exceeding the 95th and the 99.5th centile of unaffected pregnancies. Total oestriol complements beta-core fragment in urine screening for Down syndrome pregnancies. A test measuring the ratio of the two urine determinants may be a significant improvement over current serum methods for detecting Down syndrome.     

RCS of material partially loaded parallel-plate waveguide cavities

This paper analyzes electromagnetic scattering by a parallel-plate waveguide cavity whose internal region is partially loaded with materials and conducting plates. The radar cross section is investigated in terms of the loaded materials. The characteristics of cavity resonance are classified and thoroughly investigated. The numerical technique used is the point-matching method together with the edge condition for a conducting enclosure.     

Melting attack of solid plates by a high temperature liquid jet — effect of crust formation

When a molten UO₂ jet impinges on a steel structure in a reactor vessel during a severe accident, the erosion rate of the steel by the molten UO₂ jet is expected to be limited considerably by a UO₂ crust layer forming on a molten steel substrate at the jet/steel plate interface. A series of simulation experiments was performed to study the melting behavior of solid plates by high temperature liquid jets and the effects of crust forming at jet/structure interface. In the first series of experiments, salt (NaCl) was selected as the jet material and tin (Sn) as the solid structure. The experiments were conducted with varying the jet diameter (10 30 mm) and jet temperature (900 1100°C). The jets were accelerated to a range of 3 5 m/s at the nozzle outlet by gravitational force and impinged perpendicularly to the solid plate underneath. Furthermore, to check the effects of the thermo-physical properties on the erosion behaviors, preliminary experiments were performed by using a molten Al₂O₃ jet ( 2200°C) impinging on stainless steel plate at room temperature. The erosion rates obtained in the present experiments were far less than the values predicted by an analytical solution that neglects the existence of a crust layer and its thermal effects. With the inclusion of the crust behavior in the model, the experimental results were predicted fairly well. From the present experiments, a Nusselt number of the turbulent heat transfer, which takes into account simultaneous melting and freezing in the impingement region of a molten jet, is correlated by a Reynolds number and a Prandtl number as follows: Nu_m = 0.0033 Re---Pr.In conclusion, the existence of a crust layer plays an important role in the erosion process of a solid plate by the molten fuel jet with high melting point as in a reactor situation.     

Big insulin-like growth factor II-producing hepatocellular carcinoma associated with hypoglycemia

A 76-year-old female with a hepatitis C virus (HCV)-related hepatocellular carcinoma (HCC) was hospitalized because of fasting hypoglycemia. Her sera contained a low concentration of immunoreactive insulin and insulin-like growth factor (IGF)-I, while the IGF-II level was normal. However, most of the IGF-II consisted of the high molecular weight form (big IGF-II). The tumor tissue contained fetal type of IGF-II mRNA (6.0 kb). Furthermore, we found that one of the four patients examined with HCV-related HCC had big IGF-II in serum. This indicates that non-islet cell tumor hypoglycemia (NICTH) in HCV-related HCC might be accompanied by production of big IGF-II by the tumor.     

Serum human hepatocyte growth factor (hHGF) is elevated in patients with metastatic gastric carcinoma

BACKGROUND/AIMS: Hepatocyte growth factor (HGF) is a stromally derived protein growth factor that modulates epithelial cell proliferation and motility. HGF may therefore be involved in tumor progression. METHODOLOGY: We measured the immunoreactive (ir)-HGF concentration in the sera of 56 patients with human gastric carcinoma, using an enzyme-linked immunosorbent assay and evaluated its association with clinical and histopathologic factors. Clinical stages were classified in accordance with The General Rules for TNM Classification (International Union Against Cancer). RESULTS: The serum hHGF concentrations from patients with gastric carcinoma significantly increased with increasing pathologic tumor grades. Also, there were significantly higher concentrations in patients with nodal metastasis compared to patients without metastasis. The serum hHGF concentrations in patients with liver metastasis were significantly higher than in patients without liver metastasis. CONCLUSIONS: These data show that the serum hHGF concentration is elevated in gastric carcinoma patients with liver and nodal metastasis. In multivariate analysis, the serum hHGF concentration was found to be the most important independent factor in predicting overall survival. Thus, the current results suggest that HGF may be important in the progression and metastasis of gastric carcinoma.     

Endoscopic evaluation of the depth of invasion of the depressed type early gastric cancer and apparently early advanced cancer in cases of a peptic ulcer within the cancer lesion

Depressed-type early and apparently early advanced cancers were divided into two groups according to whether or not an associated peptic ulcer was present within the cancer lesion, and the accuracy of preoperative endoscopic diagnosis was reviewed. As a result it was found that evaluation of depth of invasion was more difficult in the ulcer [UL(+)] group than in the group without an ulcer [UL(-)]. In the UL(+) group it was difficult to identify endoscopic findings which indicate depth of invasion at the tip of the folds, the volume of cancer invasion of the deeper layers was small, and there many cases of invasion of deeper layers in a portion of the margins of the peptic ulcers.