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Many paleoclimatic records in Southeast Asia rely on rainfall isotope ratios as proxies for past hydroclimatic variability. However, the physical processes controlling modern rainfall isotopic behaviors in the region is poorly constrained. Here, we combined isotopic measurements at six sites across Thailand with an isotope-incorporated atmospheric circulation model (IsoGSM) and the Hybrid Single-Particle Lagrangian Integrated Trajectory (HYSPLIT) model to investigate the factors that govern the variability of precipitation isotope ratios in this region. Results show that rainfall isotope ratios are both correlated with local rainfall amount and regional outgoing longwave radiation, suggesting that rainfall isotope ratios in this region are controlled not only by local rain amount (amount effect) but also by large-scale convection. As a transition zone between the Indian monsoon and the western North Pacific monsoon, the spatial difference of observed precipitation isotope among different sites are associated with moisture source. These results highlight the importance of regional processes in determining rainfall isotope ratios in the tropics and provide constraints on the interpretation of paleo-precipitation isotope records in the context of regional climate dynamics.

A combined system comprising the TrueBeam linear accelerator and a new real-time, tumor-tracking radiotherapy system, SyncTraX, was installed in our institution. The goals of this study were to assess the capability of SyncTraX in measuring the position of a fiducial marker using color fluoroscopic images, and to evaluate the dosimetric and geometric accuracy of respiratory-gated radiotherapy using this combined system for the simple geometry. For the fundamental evaluation of respiratory-gated radiotherapy using SyncTraX, the following were performed:1) determination of dosimetric and positional characteristics of sinusoidal patterns using a motor-driven base for several gating windows; 2) measurement of time delay using an oscilloscope; 3) positional verification of sinusoidal patterns and the pattern in the case of a lung cancer patient; 4) measurement of the half-value layer (HVL in mm AL), effective kVp, and air kerma, using a solid-state detector for each fluoroscopic condition, to determine the patient dose. The dose profile in a moving phantom with gated radiotherapy having a gating window ≤ 4 mm was in good agreement with that under static conditions for each photon beam. The total time delay between TrueBeam and SyncTraX was < 227 ms for each photon beam. The mean of the positional tracking error was < 0.4 mm for sinusoidal patterns and for the pattern in the case of a lung cancer patient. The air-kerma rates from one fluoroscopy direction were 1.93 ± 0.01, 2.86 ± 0.01, 3.92 ± 0.04, 5.28 ± 0.03, and 6.60 ± 0.05 mGy/min for 70, 80, 90, 100, and 110 kV X-ray beams at 80 mA, respectively. The combined system comprising TrueBeam and SyncTraX could track the motion of the fiducial marker and control radiation delivery with reasonable accuracy; therefore, this system provides significant dosimetric improvement. However, patient exposure dose from fluoroscopy was not clinically negligible.

In high-precision radiotherapy, absolute and relative doses are evaluated for patient-specific intensity-modulated radiation therapy (IMRT) quality assurance (QA). In our institution, we use GAFCHROMIC EBT3 (EBT3) for relative dose evaluation in IMRT QA. We usually use two directional film configurations, which are in the axial and sagittal planes. The QA in our institution shows some differences between the gamma pass rates in the axial and sagittal directions. The purpose of this study was to evaluate the incident directional dependence of EBT3 by using the percent depth dose (PDD) and the off-center ratio (OCR) between EBT3 films positioned perpendicular to the beam axis and along the beam axis. Furthermore, we compared the PDD in EBT3 films positioned perpendicular to the beam axis and the PDD by using an ionization chamber. In addition, PDDs in water phantoms with and without EBT3 films were calculated by Monte Carlo simulation. The results showed that the PDD in EBT3 films positioned perpendicular to the beam axis increased with the depth from the phantom surface. Monte Carlo simulation showed the same trend as did the film measurements. The OCR results were slightly different at dose levels below 20 %. The OCR in EBT3 films positioned along the beam axis was higher than that perpendicular to the beam axis. Thus, we conclude that EBT3 film has incident directional dependence. In IMRT QA, the gamma analysis results may be affected by the incident directional dependence of EBT3 film.

Germanium is recognized as new channel material to be introduced in near future CMOS technologies. The advantages are the high hole mobility, the high p-type dopant activation and the low contact resistivity, whereas the smaller band gap results in higher off state current than Si devices. Therefore, Ge-MOSFETs are considered to be most promising to use as a pMOS counterpart of III-V nMOSFETs for high-performance CMOS devices. In order to suppress the off leakage current, Ge-on-insulator (GeOI) substrates may be preferable than bulk substrates. On the other hand, the low thermal budget of the fabrication processes can provide another opportunity for Ge devices. Sequentially stackable COMS devices may be a possible application for 3D-LSIs instead of a TSV technology. Poly-Ge CMOS devices on insulating layers may be one of solutions for the 3D-LSIs. In this paper, electrical properties and processes of high performance strained Ge nanowire pMOSFETs and poly-Ge trigate pFETs both on buried oxide (SiO2) layers, which are dedicated for the former and the latter applications, respectively, are presented. The Ge nanowire devices were formed by a two-step Ge condensation technique for the channels and a self-aligned NiGe process for the source and drain [1]. A compressive strain of around 4% along the channel direction of was observed after the condensation process, suggesting that no relaxation of the misfit strain between Si and Ge was occurred. A significantly high-hole mobility of 1922 cm2/Vs has been achieved thanks to the high strain and the good interfacial quality between the gate insulator and the Ge channel. Ion/Ioff over 105 has also been attained for the Ge nanowire pMOSFET with a gate length (Lg ) of 45 nm. Poly-Ge junction-less (JL) pFETs with a Lg down to 40 nm were formed on a SiO2 layer on a Si substrate [2]. The poly-Ge channel was naturally p-type with a hole concentration around 5x1018 cm-3 presumably due to the crystalline defects. No additional doping has been done. A high Ion/Ioff of around 105 was observed for narrow fin (7 nm) devices, although wider devices (>11 nm) exhibited degraded cut-off characteristics. We also found that the current drivability was drastically improved by using a flash lamp annealing (FLA) method due to the high hole mobility in the poly-Ge channel. A drain current value of 280 μA/μm was achieved at Vd =-1 V for the Lg =80 nm device [3], which is comparable with that of a mono-crystalline Si-pMOSFET of 130-nm technology node. In summary, two types of GeOI pMOSFETs for near-future high-performance logic CMOS-ICs and low-cost stackable applications were demonstrated. In both types of devices, the GeOI platform and non-planar gate configurations are key technologies to achieve sufficiently high Ion/Ioff values, which is one of major concerns to implement Ge devices into markets. Acknowledgement This work was granted by JSPS through FIRST Program initiated by the Council for Science and Technology Policy (CSTP). References [1] K. Ikeda et al., Symp. VLSI Tech., (2013), T30 [2] Y. Kamata et al., Symp. VLSI Tech., (2013), T94 [3] K. Usuda, ISDRS 2013 WP3-04

Purpose: Respiratory-gated radiation therapy (RT) using the real-time tumor-tracking radiotherapy (RTRT) system is an effective technique for managing tumor motion. High dosimetric and geometric accuracy is needed; however, quality assurance (QA) for respiratory-gated RT using the RTRT system has not been reported. The purpose of this study was to perform QA for respiratorygated RT using the RTRT system. Materials and Methods: The RTRT system detected the position of the fiducial marker and radiation delivery gated to the motion of the marker was performed. The dynamic anthropomorphic thorax phantom was positioned at the isocenter using the fiducial marker in the phantom. The phantom was irradiated only when the fiducial marker was within a three-dimensional gating window of ±2 mm from the planned position. First, the absolute doses were measured using anionization chamber inserted in the phantom under the stationary, gating and non-gating state for sinusoidal (nadir-to-peak amplitude [A]: 20 - 40 mm, breathing period [T]: 2 - 4 s) and the basic respiratory patterns. Second, the dose profiles were measured using Gafchromic films in the phantom under the same conditions. Differences between dose profiles were calculated to evaluate the dosimetric and geometric accuracy. Finally, differences between the actual and measured position of the fiducial marker were calculated to evaluate the tracking accuracy for sinusoidal and basic respiratory patterns. Results: For the sinusoidal patterns, the relative doses were 0.93 for non-gating and 0.99 for gating (A = 20 mm, T = 2 s), 0.94 for non-gating and 1.00 for gating (A = 20 mm, T = 4 s), 0.55 for non-gating and 1.00 for gating (A = 40 mm, T = 4 s), respectively. For the basic respiratory pattern, the relative doses were 1.00 for non-gating and 1.00 for gating, respectively. Compared to the stationary conditions, the differences in lateral distance between the 90% dose of dose profiles were 6.23 mm for non-gating and 0.36 mm for gating (A = 20 mm, T = 2 s), 8.79 mm for non-gating and 1.73 mm for gating (A = 20 mm, T = 4 s), 18.37 mm for non-gating and 0.67 mm for gating (A = 40 mm, T = 4 s), respectively. For the basic respiratory pattern, those were 5.23 mm for non-gating and 0.35 mm for gating. The root mean square (RMS) values of the tracking error were 0.18 mm (A = 20 mm, T = 2 s), 0.14 mm (A = 20 mm, T = 4 s), and 0.21 mm (A = 40 mm, T = 4 s) for sinusoidal and 0.79 mm for the basic respiratory pattern, respectively. Conclusion: We conducted QA for respiratory-gated RT using the RTRT system. The respiratory-gated RT using the RTRT system reduced the blurring effects on dose distribution with high dosimetric and geometric accuracy.

Background and purpose To report the clinical usefulness of coiled fiducial markers as an internal surrogate in gated stereotactic body radiotherapy (SBRT) for hepatocellular carcinoma (HCC) using a real-time tumor-tracking radiotherapy (RTRT) system. Materials and methods Seventeen HCC patients with Child-Pugh (CP) scores of A or B received gated SBRT (45–50 Gy in 5–10 fractions) using an RTRT system and Visicoil markers. Local control (LC), progression-free (PFS), and overall survival (OS) rates were assessed using the Kaplan-Meier method. Toxicities were assessed using the Common Terminology Criteria for Adverse Events, Version 4.0. Results Of the 17 patients, 14 had a CP score A. The mean planning target volume was 54.6 cc. Only 1 patient developed pneumothorax after marker implantation. Visicoil tracking during SBRT was possible in all cases. With a median follow-up of 16 months, 1-year LC, PFS, and OS rates were 100%, 53%, and 82%, respectively. Grade ≥ 2 late toxicity was observed in 2 patients (grade 2 duodenal ulcer and grade 3 temporary transaminase elevation). Conclusions Using an RTRT system and Visicoil markers, gated SBRT was well tolerated in patients with HCC. This can be considered a safe treatment strategy with potential for delivering favorable outcomes.

Firstly, advantages and fabrication processes for strained SiGe fin- and wire-pMOSFETs are summarized. It is shown that strained SiGe-on-insulator channels formed by the Ge condensation process is effective to keep strain in the channel and hence to boost the current drivability of pMOSFETs. Secondly, our recent progress on a new gate-stack technology using SrGex interlayer and fabrication process of narrow Ge-fin structures using anisotropic wet etching were demonstrated for all-Ge CMOS applications. It is shown that these processes are beneficial for realizing non-planar Ge-CMOS devices in future technology nodes.

PURPOSE: Cross-sectional lung ventilation (V)-perfusion (Q) imbalance in primary pulmonary arterial hypertension (PAH) and passive pulmonary hypertension (PH) was characterized by automated V/Q single-photon emission computed tomography (SPECT). MATERIALS AND METHODS: Technegas/macro-aggregated albumin SPECT-derived V/Q SPECT and V/Q profile were automatically built to characterize cross-sectional lung V-Q imbalance in 12 patients with primary (idiopathic or familial) PAH and 15 patients with passive PH associated with left ventricular dysfunction or failure. The abnormality of V/Q distribution in these patients was correlated with PaO2 and pulmonary arterial pressure and with lung morphologic changes on computed tomography (CT). RESULTS: Markedly low V/Q ratios (reverse V-Q mismatch) in the background lungs with heterogeneous V/Q distribution was seen in 12 of the 12 (100%) patients with primary PAH and in 10 of the 15 (66%) patients with passive PH, which were predominantly seen in the upper lung zone. Including these regions with reverse V-Q mismatch, the V/Q profile frequently showed flattened peaks with asymmetric and broadened V/Q distribution in all patients, with significant correlation between the standard deviation of V/Q ratios in the entire lungs and PaO2 and mean pulmonary arterial pressure (both; P

Nonspecific interstitial pneumonia (NSIP) and usual IP (UIP) preferentially involve subpleural lung zones (SPLZ), and may result in characteristic regional lung function impairment. The aim of this study was to characterize cross-sectional lung ventilation (V)-perfusion (Q) imbalance in these disorders on automated V/Q quotient single photon emission computed tomography (SPECT).99mTc-technegas/macroaggregated albumin SPECT-derived V/Q quotient SPECT and V/Q profile were automatically built for assessment of cross-sectional lung V-Q imbalance in 38 patients with NSIP or UIP. The findings of V/Q quotient SPECT were correlated with lung CT morphology. The results were compared with 12 healthy nonsmoker controls and 48 patients with chronic obstructive pulmonary disease.V/Q quotient SPECT showed 81 crescentic SPLZ with high V/Q ratios in 32 patients (84%) with NSIP or UIP, which were not observed in controls and patients with chronic obstructive pulmonary disease. Sixty-three (77.7%) of them were located at high-attenuation areas (reticular and/or ground-glass opacities) with or without small cystic air spaces (honeycombing and/or traction bronchiectasis) on CT, and 12 (14.8%) at normal lung areas. V/Q profile at the lung sections with crescentic SPLZ with high V/Q ratios showed flattened peaks with broadened V/Q ratio distribution compared with controls, and standard deviation of V/Q ratios in the entire lungs was significantly correlated with partial oxygen arterial blood pressure (P = 0.0009) and predicted diffusing capacity of the lungs for carbon monoxide (P = 0.0139). Five of eight patients with NSIP or UIP and with worsening of hypoxemia showed an extension of SPCZ with high V/Q ratios on follow-up V/Q quotient SPECT, without significant changes on CT.A high prevalence of crescentic SPLZ with high V/Q ratios is a characteristic feature of lung V-Q imbalance causing alveolar gas exchange impairment in NSIP and UIP.

Background: Because lung perfusion Tc-99m MAA of SPECT is generally acquired under the non-breath-hold condition, SPECT image quality is degraded for respiratory lung motion. To solve this problem, a new acquisition mode would need to be developed. We suggest that the acquisition mode is the detector rotating at high speed during the deep breath-hold condition and 20 sec. This acquisition method is known as high-speed detector rotation-multiplied projection single photon emission computed tomography (HSRMP-SPECT). Detail is reconstructed from projection data added while projection data are acquired several times under deep breath-hold sets. Purpose: The HSRMP-SPECT technique has been developed under the triple-head system. However, the triple-head system is a small field of view. Thus a description of the entire lung area was impossible under the deep breath-hold condition. The HSRMP-SPECT technique seems needed to make the shift to dual-head system, because the generally dual-head system has a large field of view. We were compared triple-head system with dual-head system, and researched some parameter. Result: With lung perfusion HSRMP-SPECT using the dual-head system, description of the entire lung area possible. The triple-head system of 5 projection data sets and dual-head system of 6 projection data sets nearly equaled the total count, and also the coefficient of variation is nearly same. Therefore, we were able to make the triple-head system to the dual-head system the shift on HSRMP-SPECT.

The objectives of this study are to develop a new inspection probe for complex structures using eddy current testing method (ECT), to establish the recognition technique of real flaw shape such as stress corrosion cracking (SCC), and to develop a rapid nondestructive inspection system. An ECT system consists of measurement and computational modules that are connected via a network circuit. The measurement module includes a flexible ECT sensor, which could fit on the curvature surface of radius larger than 25 mm with a mechanical manipulator. The computational module is used for SCC sizing. It includes a database of ECT signals that are used to execute numerical calculations. SCC sizing can be evaluated by comparing the measured ECT signals with the calculated ECT signals within the database. We have demonstrated that the system could be used to estimate the SCC length and depth sizing in 140 s. The accuracy of length sizing showed an RMS error of 3.7 mm and the depth sizing was 0.63 mm in this work.

The Drude tail due to photo-excited carriers in single-walled carbon nanotubes (SWNTs) has been observed in the mid-infrared region by using combination spectroscopy of synchrotron radiation and Ti:sapphire laser. It is found that the density of photo-excited carriers increases as the sample temperature is raised from 12 to 300 K, and their lifetime is of the order of minutes at 300 K. These facts suggest that the movement of photo-excited carriers is largely affected by some extrinsic defect, thus resulting in the long-lasting Drude reflection in SWNTs.

Detailed investigation of the HfSiON electrical property dependence on Hf and N concentration has been conducted. The electrical property has been correlated with the film physical structure in this study. Increase in Hf and N concentrations enhances the film dielectric constant, especially when Hf-N bonds are formed in the film. The Hf-N formation results in the bandgap narrowing, leading to barrier height reduction at the same time. In view of the figure of merit in terms of the suppression of the direct tunneling leakage current, high Hf and N may be desirable for the application of HfSiON films as alternative gate dielectrics.

In traditional pulmonary perfusion single photon emission computed tomography (SPECT), respiratory lung motion and cyclically varying changes in lung volume during image acquisition inherently degrade the image sharpness of ill-defined perfusion defects. However, because of the lack of an adequate fast imaging technique, perfusion SPECT has never been acquired under breathhold conditions, whereas breathhold images are commonly used for pulmonary magnetic resonance (MR) and computed tomographic (CT) images. Although a high-speed imaging technique combined with a multidetector SPECT system may enable SPECT images to be obtained during a short period of breathholding, image quality would be degraded owing to decreased radioactivity counts and increased statistical noise. To resolve this problem, we developed an innovative SPECT imaging technique using a triple-head SPECT system and the high-speed-detector rotation-multiplied projection (HSRMP) technique, where a single SPECT image was reconstructed from multiple respiratory dimensional breathhold projection data obtained at the same angle. HSRMP provided noiseless high-quality perfusion SPECT images by compensating for decreased radioactivity counts caused by high-speed imaging, and significantly improved image quality and perfusion defect clarity compared with traditional non-breathhold SPECT images.

Mechanisms of flux action for the growth of ZnS phosphor particles have been investigated by using a sealed quartz capsule, instead of an unsealed crucible used in practical production process. No growth of ZnS particles is found in the melted sodium chloride phase. This result is in remarkable contrast to the classical model by Leverentz, in which melted NaCl acts as flux for the ZnS particle growth. It is revealed that the fluxing agent is the vaporized ZnCl2 gas, which is formed as a result of sequential chemical reactions. A growth mechanism of ZnS particles by the chlorine cycle via ZnCl2 and Cl2 gases is proposed, with emphasis on the importance of growing spaces (voids) in the blend-mixture charged in a crucible. On the basis of the present results, it is stressed that further improvement is possible for the production process of ZnS phosphor powder.

1. Cytochrome P450 (CYP) 3A catalysis of testosterone 6beta-hydroxylation in female rat liver microsomes was significantly induced, then reached a plateau level after pretreatment with 80 mg kg(-1) day(-1) dexamethasone (DEX) for 3 days. 2. Midazolam was mainly metabolized by CYP3A in DEX-treated female rat liver microsomes from an immuno-inhibition study, and the apparent K(m) was 1.8 microM, similar to that in human microsomes. 3. Ketoconazole and erythromycin, typical CYP3A inhibitors, demonstrated extensive inhibition of midazolam metabolism in DEX-treated female rat liver microsomes, and the apparent K(i) values were 0.088 and 91.2 microM, respectively. The values were similar to those in humans, suggesting that DEX-treated female rat liver microsomes have properties similar to those of humans. 4. After oral administration of midazolam, the plasma midazolam concentration in DEX-treated female rats significantly decreased compared with control female rats. The area under the plasma concentration curve (AUC) and elimination half-life were one-11th and one-20th of those of control female rats, respectively. 5. Using DEX-treated female rats, the effect of CYP3A inhibitors on midazolam pharmacokinetics was evaluated. The AUC and maximum concentration in plasma (C(max)) increased when ketoconazole was co-administered with midazolam. 6. It was shown that the drug-drug interaction that occurs in vitro is also observed in vivo after oral administration of midazolam. In conclusion, the DEX-treated female rat could be a useful model for evaluating drug-drug interactions based on CYP3A enzyme inhibition.

Insulators with high dielectric constants (so-called high-k) have been intensively investigated for the replacement of SiO2 gate dielectric of MOS transistors for high-speed ULSIs in near future. The characterization results of the Hf-silicate gate dielectric, especially in terms of its structural transformation during high temperature annealing, are presented. Phase separation and micro-crystallization in Hf-silicates were evaluated using XPS, TEM, and XRD. Impurity diffusion through the dielectric was also examined using the backside SIMS of the p+-poly-Si/Hf-silicate/Si-substrate system. It has also been revealed that such thermal stability problems for Hf-silicates can be solved with nitrogen incorporation in the film using the physical analyses outlined above. [DOI: 10.1380/ejssnt.2003.116]

Soil moisture estimation using microwave remote sensing faces challenges of the segregation of influences mainly from roughness and vegetation. Under static surface conditions, it was found that Radarsat C-band SAR shows reasonably good correlation and sensitivity with changing soil moisture. Dynamic surface and vegetation conditions are supposed to result in a substantial reduction in radar sensitivity to soil moisture. A C-band scatterometer system (5.2 GHz) with a multi-polarization and multi-angular configuration was used 12 times to sense the soil moisture over a tall vegetated grass field. A score of vegetation and soil parameters were recorded on every occasion of the experiment. Three radar backscattering models Viz., Integral Equation Model (IEM), an empirical model and a volume scattering model, have been used to predict the backscattering phenomena. The volume scattering model, using the Distorted Born Approximation, is found to predict the backscattering phenomena reasonably well. But the surface scattering models are expectedly found to be inadequate for the purpose. The temporal variation of soil moisture does show good empirical relationship with the observed radar backscattering. But as the vegetation biomass increases, the radar shows higher sensitivity to the vegetation parameters compared to surface characteristics. A sensitivity analysis of the volume scattering model for all the parameters also reveals that the radar is more sensitive to plant parameters under high biomass conditions, particularly vegetation water content, but the sensitivity to surface characteristics, particularly to soil moisture, is also appreciable.

Rosuvastatin is a new 3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitor. The liver is the target organ for the lipid-regulating effect of rosuvastatin; therefore liver-selective uptake of this drug is a desirable property. The aim of this study was to investigate, and compare with pravastatin and simvastatin, the tissue-specific distribution of rosuvastatin. Bolus intravenous doses (5 mg/kg) of radiolabeled rosuvastatin, pravastatin, and simvastatin were administered to rats, and initial uptake clearance (CL(uptake)) in various tissues was calculated. Hepatic CL(uptake) of rosuvastatin (0.885 ml/min/g tissue) was significantly (p < 0.001) larger than that of pravastatin (0.703 ml/min/g tissue), and rosuvastatin was taken up by the hepatic cells more selectively and efficiently than pravastatin. Hepatic CL(uptake) of simvastatin (1.24 ml/min/g tissue) was significantly larger than that of rosuvastatin (p < 0.01) and pravastatin (p < 0.001). However, adrenal CL(uptake) of simvastatin (1.55 ml/min/g tissue) was larger than hepatic CL(uptake), and simvastatin was distributed to other tissues more easily than rosuvastatin. Microautoradiography of the liver, spleen, and adrenal was undertaken 5 min after administration of the study drugs; distribution was quantified by counting the number of silver grains. After administration of rosuvastatin and pravastatin, silver grains were distributed selectively in the intracellular space of the liver, but more rosuvastatin (3.3 +/- 1.0 x 10(5) particles/mm(2)) than pravastatin (2.0 +/- 0.3 x 10(5) particles/mm(2)) tended to distribute to the liver. Simvastatin was less liver-specific (it also distributed to the spleen and adrenal). The results of this study indicated that rosuvastatin was taken up by hepatic cells more selectively and more efficiently than pravastatin and simvastatin.

In order to realize high-performance stacking CMOS on insulator layers for 3D-LSIs, a technique for fabricating high-quality poly-crystalline Ge (poly-Ge) MOSFETs is mandatory. We employed the flash lamp annealing (FLA) method to grow high-quality poly-Ge by crystallization after melting an amorphous Ge layer. The Hall effect mobility of the p- and n-type poly-Ge film attained by the method was as high as 200 and 140 cm2/Vs. Tri-gate junction-less (JL) p- and nMOSFETs were successfully fabricated on the poly-Ge channels without channel doping. The p- and nMOSFET exhibited high drive currents of up to 311 and 119 µA/µm which were comparable to that of L g = 60 nm node c-Si pMOSFET, and the record value of poly-Si nMOSFET, respectively.

Summary A simple, mild and versatile new tritium ( 3 H) labelling method on a micro scale using sodium borotritide (NaB 3 H4) and a transition–metal complex catalyst is described. 3 H-labelled compounds were prepared effectively by 3 H hydrogenolysis of appendant functional groups in target compounds. The appendant functional group such as bromo, iodo or sulfonate in various target compounds can be replaced by tritium ( 3 H) in moderate yields. The new method was established by optimization of the reaction conditions and examination of its applicability using four types of model substrates in tracer runs. Then, various drug candidates and ligands for drug discovery were labelled with tritium on a micro scale. The specific radioactivity of the 3 H-labelled compounds used for the studies on receptor binding ranged from 12 to 20 Ci/mmol. Copyright # 2001 John Wiley & Sons, Ltd.

This paper focuses on deforestation impact on regional precipitation over Indochina, especially in Thailand. Analysis of observed precipitation in Thailand shows a significant decrease in precipitation only in September. Precipitation amounts at many meteorological stations in September have decreased approximately 100mm/month over the past three or four decades. Numerical experiments with a regional climate model are carried out for August and September. Results of the experiments also show a decrease in precipitation over the deforested area in September, but not in August. As the strong monsoon westerlies over Indochina disappear in September although it is typically the month of maximum precipitation, it is inferred that local deforestation impact may appear significantly only in September due to the absence of the strong external forcing. Preliminary analysis of stable isotopes in precipitation in Thailand indicates the importance of evaporation from land surface in September and October. These all suggest that local recycling of precipitation could be important for regional climate in a specific period of a year.

Results are presented for the ${}^{3}$He$(\ensuremath{\gamma},{\ensuremath{\pi}}^{+}{\ensuremath{\pi}}^{\ensuremath{-}})$ reaction in the region 380 $l~{E}_{\ensuremath{\gamma}}l~700$ MeV, investigated with the use of a 10% duty factor tagged photon beam, in conjunction with the TAGX multiparticle spectrometer. The study of such multipion photoproduction reactions has motivated a number of chiral symmetric models, and is expected to provide an insight on the role of the $\ensuremath{\Delta}$ and ${N}^{*}$ resonances in the nuclear medium. From comparisons of the data with simple reaction simulations, it was found that the data were best fit with a combination of multibody phase space channels, quasifree $\ensuremath{\Delta}$ and ${N}^{*}$, and $\ensuremath{\Delta}\ensuremath{\Delta}$ production channels. The results are compared with other double pion photoproduction reactions on hydrogen and deuterium.

Ground-base verification experiments for the soil moisture detection by spaceborne SARs (E ERS-1 and J ERS-1) were carried out. Backscattering coefficients obtained from satellite SARs were compared with those measured by ground-base scatterometer system and ground truth data of soil moisture, and the relationship between backscattering coefficients measured by SARs and soil moisture content was examined. Major results obtained from the study are as follows; (i) Backscattering coefficients measured by E ERS-1 AMI are not more sensitive to surface conditions than those by the scatterometer and have a high correlation with soil moisture content for the soil moisture range of less than 40 correlation with the saturation degree of soil moisture, but low sensitivity to it. (iii) Each land cover has its own seasonal change, which shows the possibility to classify land cover types from multitemporal SAR data. (iv) Using SAR data with visible satellite data, soil moisture distribution maps are made up and validated with qualitative observations.

This paper explores the possibility of inversion technique of surface roughness estimation using multi-incident angular data by microwave scatterometer. We made field experiments to measure soil moisture, surface roughness and soil backscatter by C-band microwave scatterometer mounted on a car. Surface roughness observed 1 dimensionally is scattered widely even in a same land cover and we have to make more than eight observations to get the representative roughness. Algorithm of the inversion technique is developed based on the surface scattering model and surface roughnesses are estimated inversely. However the observed and estimated roughnesses are quite different each other and the latter one proves to be suitable for decision of relational curve for soil moisture-backscattering coefficients.

全球スケールでの合成開口レーダ(SAR)によるモニタリングが実用化段階に入り,水文学の領域では表層土壌水分量と積雪内水分量の定量的把握が期待されている.本研究では能動型マイクロ波リモートセンシングによる表層土壌水分量に焦点を当て,地上計測用マイクロ波Cバンド散乱計を製作し,これを用いて重要な各種特性について室内実験を行なった.まずアンテナ特性などのシステム特性を電波暗室で調べる実験を行なった.さらに,この実験システムを用いて,マイクロ波土壌侵入深,土壌水分感度,入射角依存性,地表面粗度の影響について室内実験を行ない,以下の点が明らかとなった.(i)Cバンドマイクロ波の土壌への侵入深は,それが最も大きくなる乾燥時の鉛直入射状態でも10cm程度であり,SARの様なサイドルッキングレーダーでは土壌侵入深はより浅くなる.(ii)散乱計で観測される後方散乱係数と表層土壌水分量の関係を定式化する場合に実用的な表層土壌深は2.5cmである.(iii)後方散乱係数の入射角依存性は入射角が小さいほど顕著である.ただし,本室内実験システムでは30°以上の入射角については良い実験結果が得られなかった.(iv)HV偏波よりもHH偏波の方が後方散乱係数の土壌水分感度が高い.(v)対象土壌面が滑面と粗面とでは,後方散乱係数に非常に大きな差が生じる.

本論文は能動型マイクロ波リモートセンシングによる土壌水分計測の第II部であり,車載型Cバンド散乱計を作製し屋外実験を行なった.様々な土壌種類,地表面粗度,植生地を選び散乱実験を行なったところ,次のような結果が得られた.(i)可搬で組み立て型で,設定が容易な車載型Cバンド散乱計システムを構築した.(ii)30°以上の入射角についても後方散乱係数と土壌水分量の間に正の相関が見られた.しかし入射角が大きくなるに連れ,土壌水分感度,相関係数ともに小さくなる傾向が見られた.(iii)実験サイト毎に後方散乱係数と土壌水分量関係は大きく異なる.これには地表面の粗度と植生が非常に大きな影響を与えている.(iv)土壌種類よりも地表面粗度の方が後方散乱係数と土壌水分量関係に大きな影響を与えており,粗度を定量的に評価しなければならない.

Purpose: The new real-time tumor-tracking radiotherapy (RTRT) system was installed in our institution. This system consists of two x-ray tubes and color image intensifiers (I.I.s). The fiducial marker which was implanted near the tumor was tracked using color fluoroscopic images. However, the implantation of the fiducial marker is very invasive. Color fluoroscopic images enable to increase the recognition of the tumor. However, these images were not suitable to track the tumor without fiducial marker. The purpose of this study was to investigate the feasibility of markerless tracking using dual energy colored fluoroscopic images for real-time tumor-tracking radiotherapy system. Methods: The colored fluoroscopic images of static and moving phantom that had the simulated tumor (30 mm diameter sphere) were experimentally acquired using the RTRT system. The programmable respiratory motion phantom was driven using the sinusoidal pattern in cranio-caudal direction (Amplitude: 20 mm, Time: 4 s). The x-ray condition was set to 55 kV, 50 mA and 105 kV, 50 mA for low energy and high energy, respectively. Dual energy images were calculated based on the weighted logarithmic subtraction of high and low energy images of RGB images. The usefulness of dual energy imaging for real-time tracking with an automated template image matching algorithm was investigated. Results: Our proposed dual energy subtraction improve the contrast between tumor and background to suppress the bone structure. For static phantom, our results showed that high tracking accuracy using dual energy subtraction images. For moving phantom, our results showed that good tracking accuracy using dual energy subtraction images. However, tracking accuracy was dependent on tumor position, tumor size and x-ray conditions. Conclusion: We indicated that feasibility of markerless tracking using dual energy fluoroscopic images for real-time tumor-tracking radiotherapy system. Furthermore, it is needed to investigate the tracking accuracy using proposed dual energy subtraction images for clinical cases.

Purpose: The respirato ry gating system combined the TrueBeam and a new real-time tumor-tracking radiotherapy system (RTRT) was installed. The RTRT system consists of two x-ray tubes and color image intensifiers. Using fluoroscopic images, the fiducial marker which was implanted near the tumor was tracked and was used as the internal surrogate for respiratory gating. The purposes of this study was to develop the verification technique of the respiratory gating with the new RTRT using cine electronic portal image device images (EPIDs) of TrueBeam and log files of the RTRT. Methods: A patient who underwent respiratory gated SBRT of the lung using the RTRT were enrolled in this study. For a patient, the log files of three-dimensional coordinate of fiducial marker used as an internal surrogate were acquired using the RTRT. Simultaneously, the cine EPIDs were acquired during respiratory gated radiotherapy. The data acquisition was performed for one field at five sessions during the course of SBRT. The residual motion errors were calculated using the log files (Elog). The fiducial marker used as an internal surrogate into the cine EPIDs was automatically extracted by in-house software based on the template-matching algorithm. The differences between the the marker positions of cine EPIDs and digitally reconstructed radiograph were calculated (EEPID). Results: Marker detection on EPID using in-house software was influenced by low image contrast. For one field during the course of SBRT, the respiratory gating using the RTRT showed the mean ± S.D. of 95th percentile EEPID were 1.3 ± 0.3 mm,1.1 ± 0.5 mm,and those of Elog were 1.5 ± 0.2 mm, 1.1 ± 0.2 mm in LR and SI directions, respectively. Conclusion: We have developed the verification method of respiratory gating combined TrueBeam and new real-time tumor-tracking radiotherapy system using EPIDs and log files.

The profiles and J-V characteristics of P- and/or chalcogen (S, Se, or Te)-introduced Ge substrates and NiGe/Ge diodes have been investigated for a Ge nMOSFET with a NiGe source/drain. We found that chalcogen and P co-introduction caused a greater increase in the number of electrons in Ge than only P introduction. Moreover, P introduction and P and chalcogen co-introduction resulted in lower (higher) Schottky barrier height (SBH) values for NiGe/nGe (NiGe/pGe) diodes than no impurity introduction. Te and P co-introduction was most effective in modulating the SBH.

Quasi-free K + photo-production in the 12 C ( γ , K + ) reaction has been investigated in a photon energy range of 0.7–1.1 GeV. Differential cross sections for the quasi-free process of the 12 C ( γ , K + ) reaction have been obtained and they are compared with a calculation of a quasi-free K + photo-production. The effective proton number Z eff = 4.2 ± 0.6 obtained from the experiment was in good agreement with a calculation of a semi-classical attenuation model.

The [sup 3]He([gamma],[ital pp])[ital n] reaction was investigated in the photon energy range 200--500 MeV using the spectrometer TAGX, which has a solid angle for protons of [pi] sr. Two types of photon absorption, one by two protons and the other by three nucleons, were observed by looking at the undetected neutron momentum distributions. The total cross section for photon absorption by two protons shows that this process is consistent with the [ital E]2 transition.

Three-body $^{3}\mathrm{He}$ photodisintegration was measured in the photon energy range (${\mathit{E}}_{\ensuremath{\gamma}}$) of 145--425 MeV. The total cross section for photon absorption on the np pairs in $^{3}\mathrm{He}$, \ensuremath{\sigma}${(}^{3}$He(\ensuremath{\gamma},np)${\mathit{p}}_{\mathrm{sp}}$), where ${\mathit{p}}_{\mathrm{sp}}$ is a spectator proton, is reported here for the first time. The ${\mathit{E}}_{\ensuremath{\gamma}}$ dependence of the \ensuremath{\sigma} is found to scale to that of \ensuremath{\sigma}${(}^{2}$H(\ensuremath{\gamma},np)), and the ratio is determined to be \ensuremath{\sigma}${(}^{3}$He(\ensuremath{\gamma},np)${\mathit{p}}_{\mathrm{sp}}$)/\ensuremath{\sigma}${(}^{2}$H(\ensuremath{\gamma},np))=1.24\ifmmode\pm\else\textpm\fi{}0.,26.

Purpose To retrospectively investigate the distribution of the low attenuation area (LAA) on dual energy perfusion CT (DEpCT) in comparison with the results of pulmonary function tests (PFTs) and quantitative CT measurements. Materials and methods Twenty-eight patients (15 male and 13 female; mean age: 62.21 years) underwent DEpCT and PFTs within a 1-month interval. The ranges of the LAA on DEpCT were classified into six groups with attenuation values of 0–3, 0–5, 0–8, 0–10, 0–13 and 0–15HU and the ratios of LAA in each group were compared with the percentage of forced expiratory volume in the 1st second (%FEV 1.0 ), FEV 1.0 /forced vital capacity (FEV 1.0 /FVC) and the relative area of the lung with attenuation coefficients lower than −950HU (RA −950 ). Results The LAAs on the DEpCT images were significantly correlated with the RA −950 , %FEV 1.0 and FEV 1.0 /FVC, and the regression analysis showed that the best values of LAA on DEpCT were 0–10HU with RA −950 ( r =0.63), 0–8HU with %FEV 1.0 ( r =−0.52) and 0–8HU with FEV 1.0 /FVC ( r =−0.61) per patient. Conclusion The iodine disturbance on DEpCT had a moderate correlation with the results of the PFTs and RA −950 , but further examination would be needed for evaluation of iodine distribution.

Recently, a new method for acquiring single photon emission computed tomography (SPECT) data during breath-holding with a high-speed rotation (HSR-SPECT) technique was applied to hepatic-function scintigraphy. This technique can suppress motion artifact caused by respiration. However, it is challenging to apply this technique to patients with respiratory problems. Our purpose in this study was to analyze projection data and correct liver displacement due to irregular respiration during technetium-99m-diethylenetriaminepentaacetic acid galactosyl human serum albumin ((99m)Tc-GSA) liver SPECT scans. We calculated cross-correlation functions (CCFs) for both intra- and inter-projections to correct irregular projections by shifting them in the longitudinal direction enough to maximize the CCFs. We integrated all of the shifted projections and created a synthesis projection which was used to reconstruct SPECT images. To confirm the effectiveness of our method, we did both a phantom study and a clinical retrospective review. In the phantom study, blurring artifacts due to displacement were reduced using our method. Post-processing using our method showed improvements in the normalized mean square error values ranging from 0.18 to 0.06. Furthermore, our method showed no disadvantage or miss-correction if we applied our method to data without displacement. In the clinical review, our method improved the image clarity for patients who could not repeat consistent respiration. In both the phantom simulation and the clinical application, the results showed the usefulness of our method. The efficiency of our method has the potential to reduce the displacement problem caused by respiration and provides excellent matching SPECT/CT fusion images.

The effect of reflected wave and the end effect of a new oscillating-plate viscometer, constructed by Sasahara et al., have been investigated experimentally over a wide range of viscosity. The results obtained are as follows: (1) The resonant frequencies of the plate oscillations in liquid samples decrease with increasing ρμ values. However, the viscosity dependence of the resonant frequency is negligibly small when an adequate leaf-spring is used for chinning the plate attached to stem. (2) The effect of reflected wave from the wall of a vessel is negligible when the distance between the plate and wall is kept over one wavelength of the wave produced by the plate oscillations. (3) The end effect of the oscillating-plate increases with increasing not only the thickness of the plates but also the viscosity of liquids. (4) The working formula for viscosity determination by the oscillating-plate method should be corrected by considering the above two effects.

Guided wave inspection technique is effective as detecting defects like corrosion in piping. Effectiveness to the straight parts in piping by the guided wave inspection has been clarified by many researches. The inspection performance using guided wave decreases due to the unwanted wave when there is a bend part in the inspection area. On above motivation, the inspection performance could be improved if the guided wave was transmitted from many circumferentially‐set sensors based on the same principle as for phased‐array methods. Then, the validity of phased array methods using the guided wave technique was confirmed by the following experiments using a piping with bend. The delayed pulse by phased‐array methods was set from the reflected wave which was transmitted from a local defect, and it was calculated based on time reversal theory. This transmission wave was confirmed by one experiment using the guided wave focused over the bend zone. Thus, the unwanted wave caused in the bend zone could be suppressed. In addition, the reception signal processing that considered the high‐order modes was examined in the second experiment on reflected wave evaluation. By combining this transmission control with the reception signal processing, it was judged that the detection performance for local defects over the bend zone could be improved.