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A liquid-mercury target system for the MW-scale target is being developed in the world. The moment the proton beams bombard the target, stress waves will be imposed on the beam window and pressure waves will be generated in the mercury by the thermally shocked heat deposition. Provided that the negative pressure generates through its propagation in the mercury target and causes cavitation in the mercury, there is the possibility for the cavitation bubbles collapse to form pits on the interface between the mercury and the target vessel wall. In order to estimate the cavitation erosion damage due to pitting, two types of off-line tests were performed: Split Hopkinson Pressure Bar (SHPB), and Magnetic IMpact Testing Machine (MIMTM). The data on the pitting damage at the high cycle impacts up to 10 million were given by the MIMTM. As a result, it is confirmed that the mean depth erosion is predictable using a homologous line in the steady state with mass loss independently of testing machines and the incubation period is very dependent on materials and imposed pressures., 著者所属: 日本原子力研究開発機構(JAEA)

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27th European Photovoltaic Solar Energy Conference and Exhibition; 2689-2691, We employed n-type hydrogenated microcrystalline silicon oxide (μc-SiOX:H(n)) as the replacement of n-type amorphous silicon layer and back TCO in hydrogenated amorphous silicon (a-Si:H) single-junction and tandem solar cells. In contrast to conventional back reflector (BR) structure (a-Si:H(n)/TCO/Ag), comparable performances of the devices using μc-SiOX:H(n)/Ag BR structure were obtained. With the optimization of bandgap and conductivity of μc-SiOX:H(n), the a-Si:H single-junction thin-film solar cells using μc-SiOX:H(n)/Ag BR exhibited an efficiency of 9.92%, and the a-Si:H/a-Si:H tandem solar cells with μc-SiOX:H(n)/Ag BR exhibited an efficiency of 9.86%. The improvement of these cell efficiencies were originated from the increased light absorption, which was confirmed by the quantum efficiency measurement showing increased response in the long wavelength region. Except the metal contact, the all PECVD process simplified the fabrication by eliminating the sputtering TCO step and resulted in a better interface quality.

Phylogenetic analyses of Microstegium (Andropogoneae, Poaceae) and some other Andropogoneae species were conducted inferred from the ITS/5.8S sequences. As a result of this study, Microstegium is polyphyletic. There are two rather distant monophyletic clades, one with Microstegium nudum (type of Leptatherum), M. japonicum and M. somae, the other one with M. ciliatum, M. fauriei, M. geniculatum and M. vimineum (type of Microstegium). Therefore we feel justified to reinstate the genus Leptatherum and three new combinations, Leptatherum boreale, L. nudum and L. somae, are proposed.

Ceriops zippeliana, a member of the mangrove Rhizophoraceae, was first reported in 1849. It was considered to be a synonym of C. decandra, which is still widely accepted. We present morphological and molecular evidence to show that C. zippeliana is significantly distinct from C. decandra, and illustrations and an identification key to both spe

This commentary is a critical appraisal of Gil-PΓ©rez et al.'s (2002) conceptualization of constructivism. It is argued that the following aspects of their presentation are problematic: (a) Although the role of controversy is recognized, the authors implicitly subscribe to a Kuhnian perspective of `normal' science; (b) Authors fail to recognize the importance of von Glasersfeld's contribution to the understanding of constructivism in science education; (c) The fact that it is not possible to implement a constructivist pedagogy without a constructivist epistemology has been ignored; and (d) Failure to recognize that the metaphor of the `student as a developing scientist' facilitates teaching strategies as students are confronted with alternative/rival/conflicting ideas. Finally, we have shown that constructivism in science education is going through a process of continual critical appraisals. Science & Education

A liquid-mercury target system for the MW-scale target is being developed in the world. The moment the proton beams bombard the target, stress waves will be imposed on the beam window and pressure waves will be generated in the mercury by the thermally shocked heat deposition. Provided that the negative pressure generates through its propagation in the mercury target and causes cavitation in the mercury, there is the possibility for the cavitation bubbles collapse to form pits on the interface between the mercury and the target vessel wall. In order to estimate the cavitation erosion damage due to pitting, two types of off-line tests were performed: Split Hopkinson Pressure Bar (SHPB), and Magnetic IMpact Testing Machine (MIMTM). The data on the piping damage at the high cycle impacts up to 10 million were given by the MIMTM. Additionally the data obtained were compared with classical vibratory horn tests. As a result, it is confirmed that the mean depth erosion is predictable using a homologous line in the steady state with mass loss independently of testing machines and the incubation period is very dependent on materials and imposed pressures.

A spontaneous multifocal subcutaneous fibromatosis is described in 6 pig-tailed macaques (Macaca nemestrina) with simian acquired immune deficiency syndrome (simian AIDS). The lesions consisted of a proliferation of vascular fibrous tissue that was infiltrated by lymphocytes and plasma cells. One animal also had retroperitoneal fibromatosis, which has also been found in this colony of pig-tailed macaques. Progressive weight loss, diarrhea, lymphadenopathy, and neutropenia were seen. Peripheral lymph nodes were hyperplastic, and there was splenomegaly. Aggregates of lymphocytes were present in the bone marrow, kidneys, liver, and lungs. Type D retrovirus particles were found in three nodules by electron microscopy; intracytoplasmic type A and budding particles were identified in fibroblasts. In a setting of acquired immunodeficiency, these subcutaneous tumors in pig-tailed macaques present a striking analogy to Kaposi's sarcoma in human AIDS.

The ultrastructural features of pulmonary vascular lesions were studied in guinea-pigs subjected to lethal Forssman shock. Within moments after an intravenous injection of Forssman antiserum the endothelia of venules and capillaries exhibited a wide range of morphological changes. Relatively mild lesions were characterized by the appearance of focal erosions in the cell membrane, cytoplasmic swelling and vacuolization. Severe lesions were associated with overt necrosis and disintegration of the endothelial lining, leaving the basement membrane in direct communication with the intravascular compartment. Platelets and PMN-leucocytes were consistently found to be adhering to denuded or damaged vascular surfaces and forming thromboembolic obstructions within blood channels. These data support the concept that vascular endothelium is a primary target tissue in Forssman shock. In addition, our findings suggest that platelets and PMN-leucocytes may be pathogenetic determinants in the development of Forssman shock.

Curcumin (diferuloylmethane), a yellow substance from the root of the plant Curcuma longa Linn., has been demonstrated to inhibit carcinogenesis of murine skin, stomach, intestine and liver. However, the toxicology, pharmacokinetics and biologically effective dose of curcumin in humans have not been reported. This prospective phase-I study evaluated these issues of curcumin in patients with one of the following five high-risk conditions: 1) recently resected urinary bladder cancer; 2) arsenic Bowen's disease of the skin; 3) uterine cervical intraepithelial neoplasm (CIN); 4) oral leucoplakia; and 5) intestinal metaplasia of the stomach. Curcumin was taken orally for 3 months. Biopsy of the lesion sites was done immediately before and 3 months after starting curcumin treament. The starting dose was 500 mg/day. If no toxicityor = grade II was noted in at least 3 successive patients, the dose was then escalated to another level in the order of 1,000, 2,000, 4,000, 8,000, and 12,000 mg/day. The concentration of curcumin in serum and urine was determined by high pressure liquid chromatography (HPLC). A total of 25 patients were enrolled in this study. There was no treatment-related toxicity up to 8,000 mg/day. Beyond 8,000 mg/day, the bulky volume of the drug was unacceptable to the patients. The serum concentration of curcumin usually peaked at 1 to 2 hours after oral intake of crucumin and gradually declined within 12 hours. The average peak serum concentrations after taking 4,000 mg, 6,000 mg and 8,000 mg of curcumin were 0.51 +/- 0.11 microM, 0.63 +/- 0.06 microM and 1.77 +/- 1.87 microM, respectively. Urinary excretion of curcumin was undetectable. One of 4 patients with CIN and 1 of 7 patients with oral leucoplakia proceeded to develop frank malignancies in spite of curcumin treatment. In contrast, histologic improvement of precancerous lesions was seen in 1 out of 2 patients with recently resected bladder cancer, 2 out of 7 patients of oral leucoplakia, 1 out of 6 patients of intestinal metaplasia of the stomach, I out of 4 patients with CIN and 2 out of 6 patients with Bowen's disease. In conclusion, this study demonstrated that curcumin is not toxic to humans up to 8,000 mg/day when taken by mouth for 3 months. Our results also suggest a biologic effect of curcumin in the chemoprevention of cancer.