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This paper described the use of fly ash for soil amelioration of acidic soils to promote plant growth. In mining sites, acid sulfate soils/rocks, which contain sulfide minerals (e.g. pyrite FeS2), have appeared as a result of overburden excavation. The excessively acidic condition inhibits plant growth due to the dissolution of harmful elements, such as Al, Fe, and Mn. Fly ash, an alkaline byproduct of coal combustion generated in thermal power plants is expected to be adopted to ameliorate acidic soils. However, the mixing ratio of fly ash must be considered because excessive addition of fly ash can have a negative impact on plant growth due to its physical/chemical properties. The pot trials using Acacia mangium demonstrate the evolution of plant growth with a 5%–10% addition of fly ash into acidic soil. When the acidic soil has a high potential for metal dissolution, the metal ions leached from the acidic soil are large, making it difficult to improve plant growth due to osmotic and ionic stress. This work suggests that the effects of fly ash on metal ions leached from the soil have to be considered for the amelioration of acidic soil.

The disintegration of rocks by weathering plays an important role in the occurrence of Acid Mine Drainage (AMD), which is the environmental problem caused by the exposure of sulfide minerals to water and oxygen. The weathering of rocks is, generally, classified into physical or chemical weathering. However, there are few studies that focus on the complex interaction between physical and chemical weathering of rocks and on the effects of the interaction on the occurrence of AMD. This paper elucidates the complex interrelation between physical and chemical weathering of rocks as well as the progress of AMD through leaching test and weathering test with argillaceous rocks taken in open-cast coal mine in Indonesia in addition to sample analysis before and after the wetting and drying cycle: the rock samples were exposed to oxygen and water during the cycle. The results indicated that the argillaceous rocks which consist of sulfide and/or sulfate caused chemical weathering with micro-cracks on the surface of rocks through the dissolution of soluble iron and sulfur during the occurrence of AMD. Additionally, physical weathering of rocks due to clay minerals was accelerated by chemical weathering with the development of cracks with the occurrence of AMD in the argillaceous rocks containing kaolinite and pyrite. Although weathering of rocks also accelerated AMD, it was concluded that the sulfur content, the form of sulfur and iron in rocks, and the supply of oxygen significantly contributed to the occurrence of AMD.

Solid-state NMR observations of low-gamma half-integer quadrupolar nuclei, 35Cl and 37Cl, were demonstrated using a 24 T hybrid magnet (1H resonance frequency of 1.02 GHz) comprised of the high-temperature (HTS) and low-temperature (LTS) superconductors, and compared with results using a 14.1 T standard NMR magnet. While at 24 T the linewidth is 1.7 times narrower than that at 14.1 T, the gain in the sensitivity is 7.0 times because of enhanced polarization, reduced linewidth, and the use of larger rotor. A simple theoretical model was used to rationalize the sensitivity enhancements. The ratio of 35Cl and 37Cl quadrupolar couplings agrees well with the ratio of quadrupolar moments, and no isotope-dependent chemical shift has been observed. In addition, the 3QMAS spectrum of 35Cl is shown to demonstrate the high sensitivity rendered by the 24 T spectrometer.

Odontomas, developmental anomalies of tooth germ, frequently occur in familial adenomatous polyposis patients with activated Wnt/β-catenin signaling. However, roles of Wnt/β-catenin signaling in odontomas or odontogenic cells are unclear. Herein, we investigated β-catenin expression in odontomas and functions of Wnt/β-catenin signaling in tooth germ development. β-catenin frequently accumulated in nucleus and/or cellular cytoplasm of odontogenic epithelial cells in human odontoma specimens, immunohistochemically. Wnt/β-catenin signaling inhibited odontogenic epithelial cell proliferation in both cell line and tooth germ development, while inducing immature epithelial bud formation. We identified Semaphorin 3A (Sema3A) as a downstream molecule of Wnt/β-catenin signaling and showed that Wnt/β-catenin signaling-dependent reduction of Sema3A expression resulted in suppressed odontogenic epithelial cell proliferation. Sema3A expression is required in appropriate epithelial budding morphogenesis. These results suggest that Wnt/β-catenin signaling negatively regulates odontogenic epithelial cell proliferation and tooth germ development through decreased-Sema3A expression, and aberrant activation of Wnt/β-catenin signaling may associate with odontoma formation.

Nuclear spin-lattice relaxation rate T 1 −1 has been measured for the ladder sites of two single crystals Sr14Cu24O41 (Sr14-A,B) by 63Cu NMR/NQR. The hole localization around 100 K appears as a peak in the T variation of T 1 −1 (NQR). On the other hand, it is suppressed in the T 1 −1 (NMR) data under the magnetic field H ∼ 11 T, and a new peak appears around 20 K. T 1 −1 (NMR) around the peak is more enlarged for Sr14-B than for Sr14-A. Hence, holes on the ladders of Sr14-B tend to be more localized. This is considered to be an origin for the occurrence of the magnetic order in Sr14-B under H ∼ 11 T.

Dishevelled is the common mediator of canonical and non-canonical Wnt signalling pathways, which are important for embryonic development, tissue maintenance and cancer progression. In the non-canonical Wnt signalling pathway, the Rho family of small GTPases acting downstream of Dishevelled has essential roles in cell migration. The mechanisms by which the non-canonical Wnt signalling pathway regulates Rac activation remain unknown. Here we show that Daple (Dishevelled-associating protein with a high frequency of leucine residues) regulates Wnt5a-mediated activation of Rac and formation of lamellipodia through interaction with Dishevelled. Daple increases the association of Dishevelled with an isoform of atypical protein kinase C, consequently promoting Rac activation. Accordingly, Daple deficiency impairs migration of fibroblasts and epithelial cells during wound healing in vivo. These findings indicate that Daple interacts with Dishevelled to direct the Dishevelled/protein kinase λ protein complex to activate Rac, which in turn mediates the non-canonical Wnt signalling pathway required for cell migration. The non-canonical Wnt signalling pathway mediates cell migration via the GTPase Rac but the detailed mechanism is unclear. In this study, the Daple protein is shown to regulate Wnt5a mediated activation of Rac, resulting in the formation of lamellipodia and cell migration.

A total of 73 patients with carcinoma of the bile duct (59 patients) or duodenal papilla (14 patients) were reviewed with regard to the role of endoscopic retrograde cholangiopancreatography (ERCP) in preoperative assessment of these diseases. Percutaneous transhepatic cholangiography was preferred in most of the jaundiced patients and ERCP was performed after establishment of percutaneous or operative drainage above the obstruction. Pancreatography obtained in 19 patients with bile duct carcinoma revealed pancreatic invasion in 2 patients, and chronic pancreatitis in 1 patient. Other patients with normal pancreatograms included 2 patients whose initial diagnosis had been pancreatic cancer. The extent of bile duct carcinoma could be determined in 92% of 26 patients who had retrograde cholangiography, whereas it was known preoperatively in only 27% of 33 patients in whom retrograde cholangiography was not obtained. Combined use of antegrade and retrograde cholangiography performed in 13 patients was particularly useful to clearly delineate the lesion. In most of the patients with ampullary carcinoma, biopsy during ERCP confirmed the diagnosis preoperatively; 3 of these patients underwent ERCP with a different diagnosis. Biopsy after sphincterotomy revealed bile duct carcinoma in 2 patients in whom bile duct cancer was not suspected. Complications included 2 cases of cholangitis and 2 cases of mild pancreatitis. ERCP does not provide sufficient information as to the proximal bile duct anatomy and extent of the lesion, which are essential for appropriate surgical treatment. If used with precautions to prevent possible septic complications, however, it is useful in excluding pancreatic diseases by pancreatography, in specifying the distal bile duct, and in observing the duodenum and papilla. The use of several ERCP-derived techniques such as perendoscopic biopsy, sphincterotomy, and balloon catheter cholangiography substantially increases the diagnostic utility of this procedure.

In 32 patients undergoing endoscopic retrograde cholangiography with a balloon catheter, culture of bile, biliary pressure at maximal visualization of the biliary tract with iodinated contrast medium, serum iodine concentrations, and blood cultures before and after the procedure were obtained. There was a significant increase in the serum iodine concentration in five of nine patients (55.6%) with pressure between 22 cm H2O and 30 cm H2O and in nine of 13 patients (69.2%) with pressure above 30 cm H2O, while it remained low in 10 patients with pressure below 22 cm H2O. Two patients showed positive blood culture after the procedure, which yielded the same organisms as found in the bile. The biliary pressures in these two patients were 30.4 cm H2O and 38.0 cm H2O. These data suggest that during retrograde balloon catheter cholangiography: (1) cholangiovenous reflux of contrast medium develops with biliary pressure higher than 22 cm H2O, (2) the indicence of the cholangiovenous reflux increases as the pressure is elevated, and (3) regurgitation of bacteria occurs with pressure greater than 30 cm H2O. These findings are noteworthy because the number of patients who need direct cholangiography is increasing.

STABLE isotopes have a great potential as tracers in the life sciences and environmental research, but their uses are still limited compared with those of radioisotopes. Radioisotopes have been widely used as trace elements, although there are problems in handling radioactive materials and preventing environmental contamination. The increasing concern about exposure to small amounts of radioactivity has caused us to consider the advantages of stable isotopes. The detection of stable isotopes, however, is not as sensitive as that for radioactive tracers and the preparation of a sample for use in stable isotope analysis is complicated. We have looked at the possibility of using a nuclear reaction caused by accelerated charged particles as a way of detecting stable isotopes. We have developed a system of stable isotope analysis using proton elastic scattering. Elastic scattering was chosen because the cross-sections are generally an order of magnitude larger than that of other reactions. Moreover, proton elastic scattering analysis has many advantages which are absolute, multi-element, rapid and subject to automatic data handling. Using this method an analysis for 15N has been done for biological studies. Nitrogen is an important component of various organic compounds which occur naturally but it has no long-lived radioactive isotopes. Here we outline the new system, and give an example of 15N analysis.