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An efficient crack propagation (CP) simulation system based on a shell-solid finite element (FE) modeling is newly established. Three-dimensional (3D) CP simulation for a curvilinearly propagating surface crack in a steel circular hollow section (CHS) T-joint is carried out. Entire model is generated by a shell FEs, and cracked welded part is generated by a solid FEs. They are connected with a rigid body element (RBE). Stress intensity factors (SIFs) are computed for analyzing CP rate and CP direction of the crack employing the virtual crack closure-integral method (VCCM) with quadratic tetrahedral FEs. When the crack extends, only solid model is regenerated. To examine the effectiveness of the modeling, fatigue testing and simplified CP simulation results are employed. Hot spot stress (HSS) and weld toe magnification factor (Mk factor) formulas are used for the simplified CP method. CP phenomena of the fatigue test are studied through the fatigue assessment methods.

Corrosion behavior of a 316L stainless steel with harmonic microstructure was studied and compared with a sintered non-harmonic and a conventional (wrought) 316L stainless steel in 3.5% NaCl and Hanks’ solution. The study was performed using linear polarization, dynamic polarization and electrochemical impedance spectroscopy. The harmonic, conventional and non-harmonic 316L stainless steels showed similar corrosion resistance in both the solutions. However, the harmonic steel showed better passivation behavior as compared to that of the wrought and sintered non-harmonic steel. Harmonically distributed fine grains and higher twin boundary fraction were attributed to the improvement in its passivation behavior.

To minimize the deviation of the predicted creep curves obtained under constant load conditions by the original θ projection model, a new modified version that can be expressed by e = θ 1 1 - e - θ 2 t + θ 3 e θ 4 e θ 5 e t - 1 , was derived and experimentally validated in our last study. In the present study, the predictive capability of the modified θ projection model was investigated by comparing the simulated and experimentally determined creep curves of K465 and DZ125 superalloys over a range of temperatures and stresses. Furthermore, the linear relationship between creep temperature and initial stress was extended to the 5-parameter model. The results indicated that the modified model could be used as a creep life prediction method, as it described the creep curve shape and resulted in predictions that fall within a specified error interval. Meanwhile, this modified model provides a more accurate way of describing creep curves under constant load conditions. The limitations and future direction of the modified model were also discussed. In addition, this modified θ projection model shows great potential for the evaluation and assessment of the service safety of structural materials used in components governed by creep deformation.

The present work analyses the effect of harmonic microstructure on the fretting wear behavior of a flat sintered 316L stainless steel sample against a bearing steel ball as well as the mechanism of wear. The fretting behavior of the harmonic 316L stainless steel was also compared with a conventional (wrought) and a sintered non-harmonic 316L stainless steel samples. Wear resistance at lower loads (2 and 5 N) was found to be considerably higher for the harmonic 316L stainless steel sample compared to that for the conventional and the sintered non-harmonic 316L stainless steel. Higher wear resistance of the harmonic 316L steel was attributed to harder shell regions distributed in periodic fashion and higher twin boundary/area than those in the coarse grained sample and subsequent engagement of the counter ball with the finer grains. However, with the increase in load, the finer shell region starts getting pulled out due to ploughing action along with the softer core region leading to an increase in coefficient of friction as well wear volume.

Estimating long-term creep deformation and life of materials is an effective way to ensure the service safety and to reduce the cost of long-term integrity evaluation of high temperature structural materials. Since the 1980s, the θ projection model has been widely used for predicting creep lives due to its ability to capture the characteristic transitions observed in creep curves obtained under constant true stress conditions. However, the creep rupture behavior under constant load or engineering stress conditions cannot be simulated accurately using this model because of the different stress states. In this paper, creep curves obtained under constant load conditions were analyzed using a modified θ projection model by considering the increase in true stress with creep deformation during the creep tests. This model is expressed as e = θ 1 1 − e − θ 2 t + θ 3 e θ 4 e θ 5 e t − 1 , and was validated using the creep curves of K465 and DZ125 superalloys tested at a range of temperatures and engineering stresses. Moreover, it was shown that the predictive capability of the modified θ projection model was significantly improved over the original one, as it reduces the prediction uncertainty from a range of 10% to 20% to below 5%. Meanwhile, it was shown that the model can be reasonably used for predicting constant stress creep conditions, when appropriate parameters are used. The prediction performance of the modified model will be discussed in another paper. The results of this study show great potential for the evaluation and assessment of the service safety of structural materials used in applications where designs are limited by creep deformation.

Overheating exposures of turbine blades during service increased the risk of service safety in aircraft engines. Nevertheless, limited investigations about microstructural degradation induced by the overheating temperature and the effects on mechanical property of wrought superalloys were reported. In this paper, wrought superalloy GH4037 sectioned from an un-used 1st stage turbine blade of an aircraft engine was adopted to investigate the microstructural degradation caused by short-time thermal exposure at very high temperature (higher than normal service temperature) and the microstructural evolution during the mechanical tests after the short-time thermal exposures. The effects of microstructural degradation on mechanical properties including hardness, high temperature tensile properties and creep properties were also analyzed. The results indicate that gradual dissolutions of γ′ phase and grain boundary (GB) carbides were the typical manifestation of microstructural degradation in GH4037 alloy during the short-time thermal exposures at 1000–1140 °C for 3 min and 5 min. The dissolved γ′ phase and GB carbides re-precipitated in a very short time (less than 12 min) as ultra-fine particles and continuous/cellular GB carbides during 850 °C tensile tests and creep tests at 850 °C/196 MPa. Due to the re-precipitated ultra-fine γ′ phase, the tensile strength at 850 °C after exposing to 1140 °C for 3 min was analogous to those of specimens without the thermal exposure. But the re-precipitated continuous/cellular GB carbides would cause the significant decrease of tensile ductility at 850 °C and the creep elongation at 850 °C/196 MPa. On the other hand, the dissolution of γ′ phase and GB carbides during the short-time thermal exposures reduced the creep properties at 700°C/471 MPa significantly, as it took much longer time (more than 18.1 h) for the re-precipitation of γ′ phase when the overheated alloys were exposed at 700°C/471 MPa. The work provides the guidance for overheating-inspection and diagnosis of service safety for blades made of wrought superalloys.

Degradation of microstructures and mechanical properties of turbine blades during service resulted in premature failure of aircraft engines. However, few investigations about the significant decrease of mechanical properties were reported after thermal exposure at relative lower service temperature. In this study, cast superalloy K465 was thermally exposed at 900 °C and 1000 °C for 300–1000 h, and then stress rupture tests were carried out under 975 °C/225 MPa. An abnormal phenomenon was found that the stress rupture lives of specimens after thermal exposure at 900 °C were obviously lower than those at 1000 °C, which contained lower volume fraction of γ′ precipitates with coarsened and coalesced morphology. Microstructural features, including the coarsening and coalescence of γ′ precipitates, stability of carbides and precipitation of plate-like phases, were identified to characterize microstructural degradation. Microstructural observation of stress ruptured specimens indicated that cracks initiated at the interface of γ′ eutectic phase, decomposed MC carbides and plate-like μ phase or M 6 C carbides with γ matrix. Large amounts of plate-like μ phase weakened the strength of γ matrix by the depletion of solid solution strengthening elements, while the precipitation of discrete M 23 C 6 carbides along grain boundaries were attributed to the strengthening of grain boundaries after thermal exposure at 900 °C in comparison with those at 1000 °C. The precipitation of plate-like μ phase with large amounts at 900 °C combined with the stress concentration between the brittle phases and the weakened γ/γ′ matrix were attributed to the abnormality of stress rupture property in K465 superalloy. This study is helpful to understand the abnormal stress rupture property caused by microstructural degradation at different temperatures and to optimize the design and operation of turbine blades made of K465 superalloy.

Service lives of turbine blades are closely related to microstructural degradation introduced by normal and overheating service exposures. However, comparative investigation about both of microstructural degradations and the corresponding creep properties of the serviced blades has been rarely reported. In this paper, microstructure and mechanical properties of two 1st stage turbine blades, which were made of GH4037 wrought Ni-based superalloy, were investigated after service exposures in two aircraft engines for about 1600 engine operating hours. The results indicate that no obvious microstructural degradation was identified in one of the blades (Blade A) based on the characterization of grain size, grain boundary (GB) precipitates and γ′ precipitates in different locations of the blade. It was suggested that Blade A had experienced normal service exposure, the service temperature was estimated to be ≤700 °C. The dissolution and re-precipitation of GB precipitates and γ′ phase caused by overheating exposure occurred in another blade (Blade B). The highest service temperature in the region between 1/3 and 2/3 height of the airfoil in Blade B during overheating exposure was estimated to be about 1100 °C by the grain size, morphologies of GB precipitates and γ′ phase. The results of mechanical properties of two blades exhibit little degradation in Vickers hardness and creep life under 850 °C/196 MPa. However, the minimum creep rate and rupture strain were reduced due to microstructural degradation in Blade B. This study is useful to understand the real service conditions and to establish overheating inspection and diagnosis of service safety for the turbine blades made of wrought superalloys.

The damage assessment and life prediction of cast turbine blades are closely related to various microstructural degradation caused by thermal exposure at service temperatures. However, limited systematic investigations about quantitative characterization of microstructural evolution in superalloys were reported. In this paper, cast superalloy K465 was thermal exposed from 900 °C to 1050 °C for 100 h to 1500 h, then the microstructural evolution were characterized and the stress rupture tests were conducted under 975 °C/225 MPa. The experimental results indicated that γ′ precipitates showed high microstructural stability at 900 °C and below, while the decomposition of MC carbides into M6C carbides proceeded gradually in the temperature range from 900 °C to 1210 °C. Moreover, blocky M6C and M23C6 carbides precipitated in the interdendritic region and along grain boundary in different temperature ranges. The plate-like phases precipitated in the temperature range from 900 °C to 950 °C and 1000 °C to 1050 °C were identified as μ phase and M6C carbides, respectively. The amount of μ phase was much higher than that of M6C carbides. The precipitation of μ phase enriched in W and Cr were mainly attributed to the decrease of stress rupture lives for K465 superalloy after thermal exposure in the temperature range from 900 °C to 950 °C, compared with those after thermal exposure in the temperature range from 1000 °C to 1050 °C, which contained even lower γ′ volume fraction with more degradation. This study is helpful to better understand the various microstructural evolution at different temperatures and to optimize the design and assessment of service induced degradation of turbine blades made of K465 superalloy.

The occurrence of high-pressure mafic-ultramafic bodies within major shear zones is one of the indicators of paleo-subduction. In mafic granulites of the Andriamena complex (north-eastern Madagascar) we document unusual textures including garnet-clinopyroxene-quartz coronas that formed after the breakdown of orthopyroxene-plagioclase-ilmenite. Textural evidence and isochemical phase diagram calculations in the Na2O-CaO-K2O-FeO-MgO-Al2O3-SiO2-H2O-TiO2 system indicate a pressure-temperature (P-T) evolution from an isothermal (780 degrees C) pressure up to c. 24 kbar to decompression and cooling. Such a P-T trajectory is typically attained in a subduction zone setting where a gabbroic/ultramafic complex is subducted and later exhumed to the present crustal level during oceanic closure and final continental collision. The present results suggest that the presence of such deeply subducted rocks of the Andriamena complex is related to formation of the Betsimisaraka suture. LA-ICPMS U-Pb zircon dating of pelitic gneisses from the Betsimisaraka suture yields low Th/U ratios and protolith ages ranging from 2535 to 2625 Ma. A granitic gneiss from the Alaotra complex yields a zircon crystallization age of ca. 818 Ma and Th/U ratios vary from 1.08 to 2.09. K-Ar dating of muscovite and biotite from biotite-kyanite-sillimanite gneiss and garnet-biotite gneiss yields age of 486 +/- 9 Ma and 459 +/- 9 Ma respectively. We have estimated regional crustal thicknesses in NE Madagascar using a flexural inversion technique, which indicates the presence of an anomalously thick crust (c. 43 km) beneath the Antananarivo block. This result is consistent with the present concept that subduction beneath the Antananarivo block resulted in a more competent and thicker crust. The textural data, thermodynamic model, and geophysical evidence together provide a new insight to the subduction history, crustal thickening and evolution of the high-pressure Andriamena complex and its link to the terminal formation of the Betsimisaraka suture in north-eastern Madagascar. (C) 2015 Elsevier B.V. All rights reserved.

Little is known about the clinical characteristics and health-related quality of life (HQOL) of elderly patients with pulmonary Mycobacterium avium complex (pMAC) disease.To evaluate HQOL using the 36-Item Short-Form Health Survey and St George's Respiratory Questionnaire (SGRQ) and to investigate the predictors of HQOL changes among elderly patients with pMAC disease.This prospective cohort registry was conducted at Keio University Hospital, Tokyo, Japan, between May 2012 and July 2015 and included 84 patients with pMAC disease aged 75 years who had completed the HQOL questionnaire and 48 patients with pMAC disease who had been followed up and completed the HQOL questionnaire in cross-sectional and longitudinal analyses, respectively.In cross-sectional analyses, elderly patients with pMAC disease had significantly lower role-physical, general health, vitality, social functioning, role-emotional and role/social component scores than the general Japanese elderly population. Analysis of covariance revealed that patients with cavitary lesions had significantly worse physical functioning and SGRQ scores (P0.05). Longitudinal analysis showed that under-treatment, short duration of disease and positive sputum smear at baseline were predictors of worse HQOL at 12 months.Elderly patients with pMAC disease have reduced HQOL. Further large studies on HQOL are required to refine the use of this parameter in the treatment of these patients.

Mosquitoes inject saliva into a vertebrate host during blood feeding. The analysis of mosquito saliva in host skin is important for the elucidation of the inflammatory responses to mosquito bites, the development of antithrombotic drugs, and the transmission-blocking of vector-borne diseases. We produced transgenic Anopheles stephensi mosquitoes expressing the secretory luciferase protein (MetLuc) fused to a saliva protein (AAPP) in the salivary glands. The transgene product (AAPP-MetLuc) of transgenic mosquitoes exhibited both luciferase activity as a MetLuc and binding activity to collagen as an AAPP. The detection of luminescence in the skin of mice bitten by transgenic mosquitoes showed that AAPP-MetLuc was injected into the skin as a component of saliva via blood feeding. AAPP-MetLuc remained at the mosquito bite site in host skin with luciferase activity for at least 4 h after blood feeding. AAPP was also suspected of remaining at the site of injury caused by the mosquito bite and blocking platelet aggregation by binding to collagen. These results demonstrated the establishment of visualization and time-lapse analysis of mosquito saliva in living vertebrate host skin. This technique may facilitate the analysis of mosquito saliva after its injection into host skin, and the development of new drugs and disease control strategies.

We report detailed evidence for a new paleo-suture zone (the Kumta suture) on the western margin of southern India. The c. 15-km-wide, westward dipping suture zone contains garnet-biotite, fuchsite-haematite, chlorite-quartz, quartz-phengite schists, biotite augen gneiss, marble and amphibolite. The isochemical phase diagram estimations and the high-Si phengite composition of quartz-phengite schist suggest a near-peak condition of c. 18 kbar at c. 550 degrees C, followed by near-isothermal decompression. The detrital SHRIMP U-Pb zircon ages from quartz-phengite schist give four age populations ranging from 3280 to 2993 Ma. Phengite from quartz-phengite schist and biotite from garnet-biotite schist have K-Ar metamorphic ages of ca. 1326 and ca. 1385 Ma respectively. Electron microprobe-CHIME ages of in situ zircons in quartz-phengite schist (ca. 3750 Ma and ca. 1697 Ma) are consistent with the above results. The Bondla ultramafic-gabbro complex in the west of the Kumta suture compositionally represents an arc with K-Ar biotite ages from gabbro in the range 1644-1536 Ma. On the eastern side of the suture are weakly deformed and unmetamorphosed shallow westward-dipping sedimentary rocks of the Sirsi shelf, which has the following upward stratigraphy: pebbly quartzite/sandstone, turbidite, magnetite iron formation, and limestone; farther east the lower lying quartzite has an unconformable contact with ca. 2571 Ma quartzo-feldspathic gneisses of the Dharwar block with a ca. 1733 Ma biotite cooling age. To the west of the suture is a c. 60-km-wide Karwar block mainly consisting of tonalite-trondhjemite-granodiorite (TTG) and amphibolite. The TTGs have U-Pb zircon magmatic ages of ca. 3200 Ma with a rare inherited core age of ca. 3601 Ma. The K-Ar biotite cooling age from the TTGs (1746 Ma and 1796 Ma) and amphibolite (ca. 1697 Ma) represents late-stage uplift. Integration of geological, structural and geochronological data from western India and eastern Madagascar suggest diachronous ocean closure during the amalgamation of Rodinia; in the north at around ca. 1380 Ma, and a progression toward the south until ca. 750 Ma. Satellite imagery based regional structural lineaments suggests that the Betsimisaraka suture continues into western India as the Kumta suture and possibly farther south toward a suture in the Coorg area, representing in total a c. 1000 km long Rodinian suture. (C) 2013 Elsevier B.V. All rights reserved.

The first experiment at the J-PARC hadron facility, the J-PARC E19 experiment, aims at searching for the Θ + pentaquark in the hadronic reaction π − p → K − X using the missing-mass technique. Based on a superconducting magnet excited at 2.5 T, the spectrometer achieved the high mass resolution of 1.4 MeV/c2 for the Θ + production process. The first data taking was performed in the autumn of 2010. No significant structure was observed in the missing-mass spectrum. The upper limit obtained for the differential cross section is 0.26 μb/sr in the laboratory frame at a 90 % CL.

We have previously developed a robust salivary gland-specific expression system in transgenic Anopheles stephensi mosquitoes. To establish transgenic mosquito lines refractory to Plasmodium falciparum using this system, we generated a transgenic mosquito harbouring the gene encoding an anti-P. falciparum circumsporozoite protein (PfCSP) single-chain antibody (scFv) fused to DsRed in a secretory form (mDsRed-2A10 scFv). Fluorescence microscopy showed that the mDsRed-2A10 scFv was localized in the secretory cavities and ducts of the salivary glands in a secreted form. To evaluate P. falciparum transmission-blocking in a rodent malaria model, a transgenic Plasmodium berghei line expressing PfCSP in place of PbCSP (PfCSP/Pb) was constructed. The PfCSP/Pb parasites were able to bind to the mDsRed-2A10 scFv in the salivary glands of the transgenic mosquitoes. Importantly, the infectivity of the transgenic mosquitoes to mice was strongly impaired, indicating that the parasites had been inactivated. These results suggest that salivary gland-specific expression of antisporozoite molecules could be a promising strategy for blocking malaria transmission to humans.

The effectiveness of polyolefin-coated urea (Meister-5 and Meister-10; CU) in a wheat (Triticum aestivum L.)-maize (Zea mays L.) rotation system was studied in lysimeter plots located in the North China Plain for three consecutive maize-wheat-maize cropping seasons. An isotopic method was used to compare the fate of CU to that of non-coated urea (NCU), and N application rates of 0, 100, 150 and 225 kg N ha −1 were evaluated. The results showed that the nitrogen use efficiency ( 15 NUE) of CU was 13.3%–21.4% greater than that of NCU for the first crop. Alternatively, when the difference method was applied (apparent NUE), no significant variations were observed among treatments in all three seasons. Although inorganic N leached from the 1.3 m layer was less than 1% of the total applied N, unidentified losses of 15 N (losses of 15 N = 15 N applied as fertilizer – 15 N absorbed by crops – 15 N remaining in the 0–0.2 m layer – 15 N leached from the 1.3 m layer) in CU-treated plots were 24.2%–26.5% lower than those of NCU-treated plots. The nitrate concentration in the 0–1.3 m layer of CU plots at the end of the experiment was 53% lower than that of NCU-treated plots. Thus, CU increased crop N uptake from fertilizer and reduced unidentified losses of applied N, which can reduce the risk of groundwater pollution.

Recent progress and near future plan of GAMMA 10 efforts are presented. With high power plug electron cyclotron heating (ECH) up to ~ 400 kW, the ion confining potential of more than 2 kV was confirmed. The drift type low frequency fluctuations were suppressed by the positive radial electric field produced by plug ECH. It is found that the efficient EC heating on mirror devices from a strong B field side requires the minimization of the stray microwave in addition to the 100% X-mode excitation to avoid the enhancement of the ion loss. The development of a gyrotron, the key tool of these ECH experiments, has been made in collaboration with NIFS (National Institute for Fusion Science), More than 1.5 MWfor more than Is has been demonstrated at 77GHz. The plan of the boundary plasma research program with modification of GAMMA 10 is in progress. The new program includes the physics and technology studies of the divertor and SOL plasmas and PWI relevant to torus plasmas like ITER. The high heat flux experiments using the open end mirror throat has been started and we have obtained successful preliminary data, which include the heat flux of 8 MW/m2.

The flute instabilities were investigated in the GAMMA10 A-divertor magnetic field with help of computer simulations. The basic equations used in the simulation can be applied to only an axisymmetr...

In this work, results of structural characterization of high-quality ammonothermal GaN are presented. Besides expected low dislocation density (being of the order of 10 3 cm −2 ) the most interesting feature seems perfect flatness of the crystal lattice of studied crystals. Regardless the size of crystals, lattice curvature radius exceeds 100 m, whereas better crystals reveal radius of several hundred meters and the best above 1000 m. Excellent crystallinity manifests in very narrow X-ray diffraction peaks of full-width at half-maximum (FWHM) values about 16 arcsec.

Five women with an unclassifiable nonconvulsive status epilepticus (NCSE) characterized by young age at onset, prolonged confusions, focal motor seizures, and both generalized spike-and-wave discharges and focal epileptic discharges on the EEG were studied with video-EEG monitoring. Electrographically, the NCSE originated from the left frontal lobe in 4 patients, and the left hemisphere with multifocal seizure discharges in 1 patient. Focal motor seizures seemed to originate from the left hemisphere in all 5 patients, particularly from its anterior part in 3 of them. Results show that the NCSE is complex partial status epilepticus of frontal lobe origin electroclinically mimicking absence status epilepticus once it reaches a full-blown phase.

In this paper we are presenting the excellent structural parameters of truly bulk gallium nitride crystals, which were grown by using the AMMONO-Bulk Method. In the crystals grown using this method a low dislocation density in the order of 5×10 3 cm −2 is readily attainable. At the same time the lattice of ammonothermally grown crystals is extremely uniform. Regardless of the crystal size, the radius of lattice curvature is higher than 100 m, whereas in the best crystals it is higher than 1000 m. Exceptional crystallinity is also evident in a very narrow X-ray (0 0 0 2) rocking curves, with FWHM values of about 17 arcsec as measured by a standard Panalytical X’pert high-resolution diffractometer. Such excellent structural parameters of AMMONO-GaN crystals show clearly that truly bulk GaN can be grown by using a scalable method, which can be employed in mass production. The authors are convinced that crystals produced using their method will make a breakthrough in the manufacturing of high-power GaN-based devices.

Two hundred and seventy eight absence seizures were recorded from 60 patients by an intensive monitoring device. They were divided into two subtypes, typical and atypical absences based on their ictal discharges whether the spike-wave rhythm was at 3 cps or not. These two absence seizures did not differ so much with regard to loss of consciousness except that: 1) the durations of discharge in atypical absences were longer than those of typical ones, 2) the recovery from clouded consciousness to a state of full-awareness was apparently delayed in atypical absences after the termination of epileptic discharges, 3) the oral automatisms were more associated with typical absences and the decreased postural tones with atypical absences. By a numerical analysis of two parameters of spike-wave, that is, its frequency ad rhythmicity, it was shown that absences with spike-waves slower than 30 cps and with poor rhythmicity which roughly corresponded with atypical absences were more therapy-resistant in comparison with those having 3 cps spike waves and good rhythm which were usually typical absences. Sodium valproate was more effective on typical absences, however, there was no difference between typical and atypical absences in the therapeutic maintenance concentrations of serum valproate acid. We would like to emphasize that the comparison of the symptomatology between typical and atypical absences is of significance not only for understanding the etiology of the epilepsies but for the guideline of practical pharmacotherapy.

Summary Aim This large-scale study was designed to investigate the incidence of gastric cancer after Helicobacter pylori (H. pylori) eradication in Japan. Methods This study was a retrospective multicentre study performed at 23 centres in Japan. Patients in whom H. pylori had been successfully eradicated and those in whom the infection persisted were entered into the study if they had undergone an upper endoscopic examination at least once a year for five consecutive years. The incidence rates of gastric cancer during follow-up were compared between those whose infections had been successfully eradicated and those with persistent H. pylori infection. Results Three-thousand twenty-one patients were enrolled. The median follow-up was 7.7 years for the infected group and 5.9 years for the eradicated group. Gastric cancer developed in 23 (1%) of those in whom H. pylori was successfully eradicated compared with 44 (4%) of those with persistent H. pylori infection (OR = 0.36; 95% CI = 0.22–0.62). Conclusion This large-scale retrospective clinical study in Japan, which has a high mortality rate for gastric cancer, indicates that H. pylori eradication may prevent the development of gastric cancer.

Planar defects, like anti-phase boundaries (APBs) and stacking faults (SFs), are reduced by growing 3C-SiC on undulant-Si whose entire surface is covered with countered slopes oriented in the [110] and [[email protected][email protected]?0] directions. During the initial 3C-SiC growth, APBs are eliminated on each slope of an undulation. Then, one kind of SF self-vanishes. However, another kind of SF remains on the 3C-SiC surface, although its density is gradually reduced with increasing SiC thickness by combining with a counter-SF. The leakage current of a pn diode fabricated homo-epitaxially on 3C-SiC is roughly proportional to the SF density before homo-epitaxial growth. The viability of 3C-SiC grown on undulant-Si for semiconductor devices is discussed by reviewing recent reports on various MOS-FETs using it as the substrate. The key issue in the fabrication of a MOS-FET as a power-switching device operated at high-voltage is to reduce the leakage-current at the pn junction, thereby eliminating SFs.

Objective Resection of tumors involving the motor area frequently results in postoperative motor deficits. In an attempt to prevent poor motor outcomes, our institution has utilized preoperative fMRI and tractography as well as intraoperative cortical mapping and continuous motor tasks during awake surgery in patients with motor area tumors. In one case, a patient demonstrated deterioration in continuous motor task performance before initiation of tumor resection. Thus, the goal of this study was to evaluate the relationship between head position and development of intraoperative or postoperative motor deficits in five patients with motor area tumors. Clinical presentation In four cases, the patient's head was rotated 60 degrees from the supine position. In two cases, in which the tumor was located relatively medially, deterioration in continuous motor task function was noted prior to resection of the tumor. In the two other cases, in which the tumor was located relatively laterally, there was no deterioration of continuous motor task performance until resection of the tumor. Another patient, in whom the tumor was located relatively medially, underwent surgery with the head positioned straight and with the patient in a half-sitting position. This patient did not experience deterioration of continuous motor task performance during the surgery. Conclusion These data suggest that head positioning can have a significant impact on motor function in patients with motor area tumors. Furthermore, the straight head position may be the preferred positioning, particularly for patients with tumors located on the medial side of motor area.

Endoscopic diagnosis of Helicobacter pylori infection, before biopsies and serological tests are performed, is possible through careful analysis of the network of superficial vessels in patients with gastritis. At standard endoscopy, a regular arrangement of the collecting venules (RAC) is visible as numerous minute red points in the corpus of the noninfected stomach, and is not visible in H. pylori gastritis. Magnifying endoscopy provides more precise information concerning the collecting venules, the network of capillaries surrounding the gastric pits, the swelling of the surface epithelium between pits, and the enlargement and destruction of the pits. The magnified appearance is classified as Z-0 (noninfected stomach) or as Z-1 to Z-3 for successive degrees of mucosal damage in the infected stomach. Histological controls confirm the reliability of the endoscopic classification. Magnifying endoscopy also proves helpful in the assessment of completeness of eradication of H. pylori.

This experiment was conducted in maize field plots to study the effects of controlled release and application depth of urea on soil microbial biomass and activities at two depths of surface soil of a Japanese Andisol from June to September, 2001. Three N amendment treatments and a Control were included in this experiment: deep application (8 cm) of controlled release urea; deep application (8 cm) of conventional urea; surface application of conventional urea; Control, without N application. Prior to this experiment, the field plots received the same N fertilizer treatments for two consecutive years under maize/barley rotation. Soil microbial biomass, dehydrogenase and nitrification activities exhibited great vertical and temporal variations during the maize growth season, and the microbial biomass was significantly correlated to soil water-filled pore space (p

The goal of the present study was to determine the efficacy of preoperative fMRI, tractography, and intraoperative continuous task during awake surgery in preserving postoperative motor function in patients undergoing resection of metastatic brain tumors in or near the primary motor area. Three patients with metastatic brain tumors in the primary motor area elected to undergo surgical treatment. Preoperative fMRI and tractography were performed, and various primary motor areas (e. g., hand, arm, face and leg) were identified and confirmed by cortical mapping or by the outcome of awake surgery. Cortical mapping and continuous appropriate task were performed during awake surgery. Preoperative fMRI and tractography correctly identified the primary motor area. In contrast, cortical mapping identified the gyrus of the primary motor area but was unable to identify specific primary motor areas, such as those for the hand or arm, which were compressed by the tumor. Tumor resection was terminated when any deterioration in continuous task performance was observed during awake surgery. Paresis was transient and resolved within one week in all cases. The combination of preoperative fMRI, tractography and continuous task during awake surgery helped to maintain motor function following surgical management of metastatic brain tumors of the primary motor cortex.

Rice (Oryza sativa) was grown in sunlit, semi-closed growth chambers (4×3×2 m, L×W×H) at 650 μl l−1 CO2 (elevated CO2) to determine: (1) rice root-derived carbon (C) input into the soil under elevated CO2 in one growing season, and (2) the effect of the newly input C on decomposition of the more recalcitrant native soil organic C. The initial δ13C value of the experimental soil was −25.8‰, which was 6‰ less depleted in 13C than the plants grown under elevated CO2. Significant changes in δ13C of the soil organic C were detected after one growing season. The amount of new soil C input was estimated to be 0.9 t ha−1 (or 2.1%) at 30 kg N ha−1 and 1.8 t ha−1 (4.1%) at 90 kg N ha−1. Changes in soil δ13C suggested that the surface 5 cm of soil received more C input from plants than soils below. Laboratory incubation (25 °C) of soils from different horizons indicated that increased availability of the labile plant-derived C in the soil reduced decomposition of the native soil organic C. Provided the retardant effect of the new C on old soil organic C holds in the field in the longer-term, paddy soils will likely sequester more C from the atmosphere if more plant C enters the soil under elevated atmospheric CO2.

The local structure of ordered and disordered PbIn 1/2 Nb 1/2 O 3 has been investigated as a function of temperature using X-ray absorption fine structure (XAFS) technique. Both EXAFS (extended XAFS) and near edge structure of the spectra were analysed. Radial distribution of oxygen atoms around Nb appeared to be similar for the both modifications and independent of the temperature. Presence of the pre-edge peak in the spectra indicated, that the value of the Nb displacement is quite large both below and above the phase transition point. The local structure of PbIn 1/2 O 3 is discussed in comparison with the other Nb-containing perovskite compounds.