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[en] This book gives descriptions of environmental pollution such as water and soil pollution, harmful chemicals substances and radiation, nature protection on wild animals, wild plants, and nature park, environmental assessment, and environmental management. It deals with the earth environment on change and the cause of the earth environment, ozone layer, global warming and acid fallout, plan for the earth control and environment information and information system.
[en] The detailed temperature(T) map was made by using land sat TM heat band data for avoiding chillinginjury of cabbage in choshi Area, Chiba Prefecture. The accuracy was verified with the radiation and air Ts observed on surface. 1. The daily minimum leaf T of cabbage head in Togawadai-cho was always lower than that in Takagaminishi-cho. The positive correlation of daily minimum leaf T of cabbage head was observed between Togawadai-cho and Takagaminishi-cho. 2. The daily minimum leaf T of cabbage head had positive correlation with the daily minimum air T in both Togawadai-cho and Takagaminishi-cho. The daily minimum leaf T of cabbage head in Takagaminisih-cho became much low with decreasing the daily minimum air T compared with that in Togawadai-cho. 3. CCT map made from land sat TM heat band date was transformed into radiation and air T maps using radiation T and air T of simultaneous surface observation, respectively. 4. Both radiation and air T maps were geometrically corrected, and were piled up on topographical map. It was observed that high T spot was located at low, vacancy or lawn place, and low T spot was located at grove, streets, playground or slope. 5. The surface T and air Tin both radiation and air T maps were accurately corresponded to radiation and air T of surface observation in cabbage field at same time, respectively
[en] It is known that use of hormone replacement therapy (HRT) by postmenopausal women increases the risk of breast cancer. In this study, oestrogen receptor (ER)-α expression is examined using standard immunoperoxidase technique. Normal breast samples of 11 Australian postmenopausal women have been included in the ER-α study; the result showed a strong correlation (r"2 = 0.80) between ER-α expression in normal breast epithelial cells and body mass index (BMI) in normal women who currently use HRT. This finding confirms that the possibility of increased risk of breast cancer associated with increased ER-α expression in normal breast epithelial cells, in turn associated with high BMI and the use of HRT
[en] Since its first introduction approximately 10 years ago, there has been extensive progress in the application of magnetic resonance imaging (MRI) to the detection and diagnosis of breast cancer. Contrast-enhanced MRI has been shown to have value in the diagnostic work-up of women who present with mammogram or clinical abnormalities. In addition, it has been demonstrated that MRI can detect mammogram occult multifocal cancer in patients who present with unifocal disease. Advances in risk stratification and limitations in mammography have stimulated interest in the use of MRI to screen high-risk women for cancer. Several studies of MRI high-risk screening are ongoing. Preliminary results are encouraging
[en] Magnetic resonance imaging (MRI) techniques enable vascular function to be mapped with high spatial resolution. Current methods for imaging in breast cancer are described, and a review of recent studies that compared dynamic contrast-enhanced MRI with histopathological indicators of tumour vascular status is provided. These studies show correlation between in vivo dynamic contrast measurements and in vitro histopathology. Dynamic contrast enhanced MRI is also being applied to assessment of the response of breast tumours to treatment
[en] Hypoxia-inducible factor-1 (HIF), which is centrally involved in physiological oxygen homeostasis, is also activated in the majority of tumours. Activation of HIF can occur through genetic mechanisms or as a result of hypoxia within the tumour microenvironment. In some cases HIF activation appears to be intimately linked to the proliferative stimulus itself. HIF affects patterns of gene expression and tumour growth, although precise effects vary between tumour types. Modulation of HIF activity, if correctly applied, may be therapeutically beneficial in tumour therapy
[en] The E-cadherin-catenin complex plays a crucial role in epithelial cell-cell adhesion and in the maintenance of tissue architecture. Perturbation in the expression or function of this complex results in loss of intercellular adhesion, with possible consequent cell transformation and tumour progression. We studied the alterations of E-cadherin and β-catenin in a set of 50 primary gastric tumours by using loss of heterozygosity (LOH) analysis, gene mutation screening, detection of aberrant transcripts and immunohistochemistry (IHC). A high frequency (75%) of LOH was detected at 16q22.1 containing E-cadherin locus. Three cases (6%) showed the identical missense mutation, A592T. This mutation is not likely to contribute strongly to the carcinogenesis of gastric cancer, because a low frequency (1.6%) of this mutation was also found in 187 normal individuals. We also detected a low frequency (0.36%, 0%) of this mutation in 280 breast tumours and 444 other tumours, including colon and rectum, lung, endometrium, ovary, testis, kidney, thyroid carcinomas and sarcomas, respectively. We also analyzed the aberrant E-cadherin mRNAs in the gastric tumours and found that 7 tumours (18%) had aberrant mRNAs in addition to the normal mRNA. These aberrant mRNAs may produce abnormal E-cadherin molecules, resulting in weak cell-cell adhesion and invasive behaviour of carcinoma cells. Reduced expression of E-cadherin and β-catenin was identified at the frequency of 42% and 28%, respectively. Specially, 11 tumours (22%) exhibited positive cytoplasmic staining for β-catenin IHC. An association was found between reduced expression of E-cadherin and β-catenin. Moreover, an association was detected between reduced expression of E-cadherin and diffuse histotype. Our results support the hypothesis that alterations of E-cadherin and β-catenin play a role in the initiation and progression of gastric cancer
[en] CeRhSi3 has the large electronic specific-heat coefficient mJ/mol K2 and the high Kondo temperature TK∼100 K, although its magnetic susceptibility follows the Curie–Weiss law and the specific heat indicates magnetic ordering at 1.8 K. In order to elucidate the 4f-electron nature in CeRhSi3, we have grown single crystals of CeRhSi3 and of its reference material LaRhSi3 and measured the electrical resistivity, the magnetic susceptibility and the de Haas–van Alphen (dHvA) effect. Comparison of the angular dependence of the dHvA frequency in CeRhSi3 to that in LaRhSi3, indicates that the 4f-electrons of CeRhSi3 are itinerant.
[en] 6H-SiC bulk single crystals grown by physical vapor transport (PVT) were investigated by deep-level transient spectroscopy (DLTS) and electron paramagnetic resonance (EPR). One of the observed deep level defects was identified as isolated tungsten on Si sites by EPR. The electron spin of could be explained by W5+ (5d1). This is equivalent to the single positive charge state of a double donor when taking into account the Fermi level position in the n-type samples. The interpretation is also consistent with the DLTS detection of a W related deep level which showed a behavior of the capture of electrons and holes that hints at a double donor. In addition a tantalum related deep level is tentatively discussed. W and Ta were incorporated on electrically active sites in 6H-SiC only in low concentrations (2–4×1014 cm−3) during crystal growth by PVT.
[en] High-Tc superconductor is considered as alternately stacked metal and insulating layers. The electric field is applied along the stacking direction and investigated in the frame of Ginzburg–Landau theory with the coupling g3 between metallic layers for the transition temperature Tc. Then the system of equations for Tc can be solved by the transfer matrix method. The shift of the transition temperature is analytically derived and we find the criterion for the enhancement of Tc while the electric field is applied.