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著者人数: 91名(所属. 宇宙航空研究開発機構宇宙科学研究所(JAXA)(ISAS): 海老沢, 研; 福家, 英之; 森, 国城; 西村, 純; 高柳, 昌弘; 冨田, 洋; 上野, 史郎), Number of authors: 91(Affiliation. Institute of Space and Atronautical Science, Japan Aerospace Exploration Agency (JAXA)(ISAS): Ebisawa, Ken; Fuke, Hideyuki; Mori, Kunishiro; Nishimura, Jun; Takayanagi, Masahiro; Tomida, Hiroshi; Ueno, Shiro), Accepted: 2018-07-03, 資料番号: SA1180102000

著者人数: 91名（所属. 宇宙航空研究開発機構宇宙科学研究所(JAXA)(ISAS): 海老沢, 研; 福家, 英之; 森, 國城; 西村, 純; 高柳, 昌弘; 上野, 史郎), Accepted: 2018-02-26, 資料番号: SA1170331000

The Kaguya gamma-ray spectrometer (KGRS) has great potential to precisely determine the absolute abundances of natural radioactive elements K, Th and U on the lunar surface because of its excellent spectroscopic performance. In order to achieve the best performance of the KGRS, it is important to know the spatial response function (SRF) that describes the directional sensitivity of the KGRS. The SRF is derived by a series of Monte Carlo simulations of gamma-ray transport in the sensor of the KGRS using the full-fledged simulation model of the KGRS, and is studied in detail. In this paper, the method for deriving absolute abundance of natural radioactive elements based on the SRF is described for the analysis of KGRS data, which is also applicable to any gamma-ray remote sensings. In the preliminary analysis of KGRS data, we determined the absolute abundances of K and Th on the lunar surface without using any previous knowledge of chemical information gained from Apollo samples, lunar meteorites and/or previous lunar remote sensings. The results are compared with the previous measurements and the difference and the correspondence are discussed. Future detailed analysis of KGRS data will provide new and more precise maps of K, Th and U on the lunar surface.

The processes of penetration, trapping, and acceleration of solar protons in the Earth’s magneto-sphere during magnetic storms in November 2004 and January 2005 are studied based on the energetic particle measurements on the CORONAS-F and SERVIS-1 satellites. Acceleration of protons by 1–2 orders of magnitude was observed after trapping of solar protons with an energy of 1–15 MeV during the recovery phase of the magnetic storm of November 7–8, 2004. This acceleration was accompanied by an earthward shift of the particle flux maximum for several days, during which the series of magnetic storms continued. The process of relativistic electron acceleration proceeded simultaneously and according to a similar scenario including acceleration of protons. At the end of this period, the intensification was terminated by the process of precipitation, and a new proton belt split with the formation of two maximums at L ∼ 2 and 3. In the January 2005 series of moderate storms, solar protons were trapped at L = 3.7 during the storm of January 17–18. However, during the magnetic storm of January 21, these particles fell in the zone of quasi-trapping, or precipitated into the atmosphere, or died in the magnetosheath. At the same time, the belts that were formed in November at L ∼ 2 and 3 remained unchanged. Transformations of the proton (and electron) belts during strong magnetic storms change the intensity and structure of belts for a long time. Thus, the consequences of changes during the July 2004 storm did not disappear until November disturbances.

Lunar-based measurement of galactic cosmic ray (GCR) nuclei with a high precision is a challenging approach in cosmic ray research for the coming 20 years. This approach focuses to measure the elemental composition of Pt- and Pb-groups, actinide and possibly trans-uranic nuclei of Pu and Cm. The observation covers a wide range of scientific themes including the study on the origin of GCR nuclei, the characteristic time, heating and acceleration mechanism of GCR particles. A large-scaled particle telescope is required in order to measure those nuclides with high precision. Solid state nuclear track detectors (SSTDs) with a geometric factor of about 1000 m 2 sr allow us to measure them easily. Fluorescent nuclear track detector such as Al 2 O 3 doped with C and Mg is the best candidate at present among SSTDs for a lunar-based experiment which is currently the focus of an international program of scientific investigation. A permanent sunshine region near crater at lunar polar region is thought to be an excellent site. A two-year-exposure by the large-scaled telescope would result in the detection of about 30,000 actinides in GCRs.

It is a case study of a chain of three magnetic storms with a special attention to the particle dynamics based on CORONAS-F and SERVIS-1 low altitude satellite measurements. Solar proton penetration inside the polar cap and inner magnetosphere and dynamics at different phases of the magnetic storms was studied. We found, that solar protons were captured to the inner radiation belt at the recovery phase of the first and the second magnetic storms and additionally accelerated during the last one. No evidence of sudden commencement (SC) particle injection was found. Enhanced solar proton belt intensity with small pitch angles decreased slowly during satellite orbits for 30 days until the next magnetic storm. Then in 20–30 h we registered strong precipitation of these protons followed by the trapped proton flux dropout. Intensity decrease was more pronounced at lower altitudes and higher particle energies.

Observation of trans-iron nuclei in galactic cosmic rays ( Z ⩾ 30 ) requires a high performance cosmic ray detector telescope with a large exposure area because of their extremely low fluxes. A solid-state track detector such as CR-39 has the advantage of easy extension of exposure area, but it is necessary to raise the Z / β detection threshold in order to suppress background tracks produced by galactic cosmic rays with Z / β 30 . The track registration sensitivity and detection threshold for heavy ions with various Z * / β were verified by using track detectors of copolymers of CR-39 and DAP (diallyl phthalate) with various DAP concentration. We found that it is possible to control the Z * / β detection threshold of copolymers by changing DAP concentration. In order to detect heavy ions with Z * / β ⩾ 30 , the optimum DAP concentration was found to be approximately 50%.

We report experimental results obtained by the emulsion chambers on board of the long duration balloon. We have been carrying out the trans-Siberian-continental balloon flight since 1995, and the results from 1995 to 1996 experiments are presented here. Total exposure of these two years amounts to 231.5 m 2 h at the average altitude of ∼32 km. The energy range covers 10–500 TeV for proton-primary, 3–70 TeV/n for helium-primary, and 1–5 TeV/n for Fe-group ( Z =26–28), though statistics of heavy components is not yet enough. Our preliminary data show that the spectra of the proton and the helium have nearly the same power indices ∼2.80, while those of heavier ones become gradually harder as the mass gets heavier, for instance the index is ∼2.70 for CNO-group and ∼2.55 for Fe-group. It is remarkable that a very high energy proton with multi-PeV is detected in 1995 experiment, and the estimated flux of this event coincides with a simple extrapolation from the energy spectrum with the power index 2.8 observed in the range 10–500 TeV. It indicates that there is no spectral break at around 100 TeV, in contrast to the maximum energy predicted by the current shock-wave acceleration model. This evidence requires some modification on the acceleration and/or propagation mechanism. Also we present all-particle spectrum and the average primary mass in the energy range 20–1000 TeV/particle. Our preliminary data show no drastic change in mass composition over the wide energy range, at least up to 1 PeV/particle, though the statistics is not yet enough to confirm it concretely. The flight performance and the procedure of the analysis, particularly the energy determination methods and the detection efficiency calculation are also given.

We report experimental results obtained by using a wide-gap type emulsion chamber flown in the first Japanese-Russo joint balloon project, called RUNJOB ( RU ssia- N ippon JO int B alloon-program). Two balloons were launched from Kamchatka in July 1995, and both were recovered successfully near the Volga River. The exposure time was 130 hours for the first flight and 168 hours for the second. The mean ceiling altitude, in both flights, was 32 km corresponding to 10 g/cm 2 . Total area of the emulsion chamber was 0.8 m 2 , and the thickness 0.385 and 2.28 collision m.f.p.'s for vertically incident proton- and iron-primaries, respectively. We detected 381 showers using Fuji-#200-type X-ray film; of these 174 showers were due to atmospheric secondary γ-rays, and the rest 207 came from nuclear components. The energy range covers 20∼200 TeV for proton-primary, 3∼30 TeV/nucleon for helium-primary, and 0.7∼5 TeV/nucleon for iron-primary. We give the energy spectra for various elements (proton, helium, …, iron) as well as the all-particle spectrum and the average mass of the cosmic-ray primaries.

The latest results of studies of the gamma-ray spectra recorded together with charged particles in the Russian-Nippon Joint Balloon (RUNJOB) experiment are presented. A comparison of the experimental spectra with the results of the calculations based on assumptions of different intensities of the gamma-ray spec- tra demonstrates that the previously published intensities of primary cosmic rays measured in the RUNJOB experiments are underestimated.

The helium isotopes were observed by Heavy Ion Telescope (HIT) onboard the TSUBASA satellite from March, 2002 to September, 2003 in the geostationary transfer orbit. The mass resolution of the HIT instrument is ~ 0.25 amu in energy range 20÷43 MeV/nucleon for helium isotopes. Helium data in the quiet periods were analyzed to obtain the spatial and temporal variation of fluxes of helium isotopes, 3 He and 4 He . From this analysis, the enhancement of 3 He flux as compared with 4 He one in low L-value was found. Both of the helium fluxes strongly fluctuated in their L-distributions in each period.

A precise measurement of elemental abundances of galactic cosmic rays from charges Z = 20 to 34 was made by TIGER balloon experiment. Using the various path lengths in the atmosphere between 4 and 16 g/cm2 from the TIGER flight data, we derived the attenuation length of iron nuclei with the energy above 2.5 GeV/n in the atmosphere. As the result, we obtained the attenuation length of 15.5 ± 0.6 g/cm 2 which is consistent with previous results of balloon measurements.

We analyze the spectra measured by the Gamma Ray Spectrometer (GRS) on board the SELENE satellite orbiting the Moon. The spectra consist in 8192 energy channels ranging from 0 to 12 MeV and exhibiting lines of interest (O, Mg, Al, Si, Ti, Ca, Fe, K, Th, and U) superposed on a continuum. We have also analysed the data with various multivariate techniques, one of them being the Independent Component Analysis. We have used the JADE algorithm for our analysis that we focused in the energy range from 750 to 3000 keV. We identify at least three meaningful components. The first one is correlated to the Thorium map. The corresponding correlation coefficient spectrum exhibits the lines of Thorium, Potassium and Uranium. The second component is clearly correlated with the Iron as shown on its corresponding spectrum. Finally the third component seems to be related to the altitude of the spacecraft. This work shows that maps of elements such as iron will be available with the GRS data by a purely statistical analysis.

Ambient dose equivalent on the lunar surface is estimated as contribution from galactic cosmic rays, secondary neutrons and γ rays from the lunar surface. Since the cosmic ray flux on the lunar surface varies with the phase of the solar activity, radiation doses on the surface are calculated of the three cases of this activity; the maximum, the minimum and the average. To estimate the doses of the secondary particles, Monte Carlo simulation library Geant4 is applied. As a result, total annual dose equivalent of about 225 mSv/yr on the lunar surface is expected during the quiet time of solar activity. The dose of neutrons and γ rays reaches to 50 mSv/yr and 2 mSv/yr, respectively. In particular, fast neutrons have the largest contribution to the total neutron dose. The dependency of total neutron dose for mare and highland region of the Moon is small on the lunar surface as comparing with that for solar activity.

DNA-dependent protein kinase (DNA-PK), a serine/threonine kinase composed of p470 catalytic subunit (DNA-PKcs) and p85/p70 heterodimer (Ku antigen), is considered a critical enzyme in the repair of the DNA double-strand breaks (DSB) that are the major lethal lesions induced by ionizing radiation. We investigated the expression of DNA-PK subunits in human tumors.We examined immunohistochemically the biopsy specimens of 44 patients with oropharyngeal carcinoma and 32 patients with hypopharyngeal carcinoma who had been treated with radiotherapy.Immunopositivity to Ku85 and DNA-PKcs was found in all patients. The staining of Ku85 and DNA-PKcs was nuclear, with none of the normal epithelial cells or malignant cells exhibiting cytoplasmic or membrane immunoreactivity. Normal epithelial cells were all stained intensely. In tumors, intense nuclear staining of DNA-PKcs was seen in 75 of 76 tumors, while that of Ku85 was seen in all 76 patients. The radiation responses of a primary tumor that was stained weakly with DNA-PKcs were excellent.Our results suggest the possibility of predicting the intrinsic radiosensitivity of human tumors in clinics able to perform immunohistochemical analysis of DNA-PK.

This paper demonstrates that a biologically equivalent dose distribution including volume effect can be generated. Since the time-dose-fractionation (TDF) concept is convenient for comparing various radiation treatment schedules, TDF distribution maps are made on the basis of the physical dose distribution. On the other hand, the dose volume histogram is useful to evaluate volume effect, but is not necessarily an easy approach owing to the absence of spatial linkage. If distribution maps also representing the volume effect could actually be made, it would become easier to simultaneously predict both tumor control probability and the normal tissue complication rate. Because such tools should be very useful for planning radiotherapy, we proposed an experimental volume effect model. In this, one pixel is affected by all its surrounding pixels and the effect depends on the distance between pixels, volume, and the irradiated dose of another pixel. When the model was adapted to the conventional power law model, we could acquire a new equation with mathematical analysis. This permitted us to calculate the volume effect on each voxel within the treatment volume. Using a personal computer and treatment planning system, we calculated the "TDF-volume" distribution and drew maps based on this equation and the TDF values of each voxel for radiotherapy of a pelvic tumor.

An unusual case of acquired development of anomalous intrapulmonary venous connection with pulmonary venous stenosis is presented. Appearances on a chest radiograph resembled the "scimitar" sign in a patient with previous surgery for partial anomalous pulmonary venous return. Spiral CT and pulmonary arteriography showed stenosis of the right upper pulmonary vein and an anomalous intrapulmonary venous connection between the right upper pulmonary vein and the right lower pulmonary vein. We consider the slow progression of pulmonary vein stenosis led to anomalous intrapulmonary venous connection as an intrapulmonary collateral.

99mTc-GSA (galactosyl serum albumin) receptor amount (Ro) was estimated by a non-linear 3-compartment model of the ligand-receptor binding without blood sampling. Forward/reverse rate constants and receptor amount were assumed to be variable. Relationship between this parameter and other conventional parameters including ICG R15 (15-minutes retention rate of indocyanine green) was evaluated for 43 surgical candidates with liver tumors. Linear relationships between Ro and HH15 and LHL15 were R2 = 0.73 and 0.72, respectively. Linear relationship between Ro and Rmax, the maximum removal rate, is also good (R2 = 0.84), and the regression line (y = 0.038x + 0.066) was slightly over 0 at y-interception. Linear relationship between Ro and ICG R15, was poor (R2 = 0.39) and relationship was rather a concave shape. Linear relationship of reduction rate between Ro and non-tumor tissue volume of the liver, which assessed at the same day of two weeks after the operation, was y = 1.09x - 0.01 (R2 = 0.82). GSA receptor amount, Ro, seems to change proportional to non-tumor liver tissue volume changing before and after hepatectomy. Complementary to ICG R15, it may be an useful and intuitive parameter for hepatectomy.

Sixty-three patients with squamous cell carcinoma of the hypopharynx were treated at the University of Tokyo between 1985 and 1993. Twelve patients were treated with surgery alone, 16 with preoperative irradiation, 26 with postoperative irradiation, and nine with irradiation alone. A tumor dose of 50 Gy (25 fractions/5 weeks) was used in postoperative irradiation, 40-60 Gy in preoperative irradiation, and 70 Gy in irradiation alone. When "number of indications," including, for example, partial pharyngectomy, positive or close (or = 5 mm) margin, and extracapsular extension, was used for multivariate analysis in patients who underwent surgery, it proved to be the only significant prognostic factor for gross survival. Six of seven patients with a positive surgical margin or close margin who received postoperative irradiation had local recurrence. A tumor dose of 50 Gy (25 fractions/5 weeks) in postoperative irradiation is not enough. It is difficult to cure by irradiation metastases to the parapharyngeal lymph nodes large enough to be detected with CT. It is necessary to irradiate parapharyngeal lymph nodes prophylactically, but 50 Gy in postoperative irradiation may not be enough from our results. The same may be true for metastases to the paratracheal nodes, which lie close to the lower poles of the thyroid gland or within the superior mediastinum and are difficult to access through surgery. In the patients who were operated on, N stage and the number of lymph node metastases were significant for gross survival. When "number of indications" was used for analysis, "number of indications" proved to be the most significant prognostic factor for gross survival.

We defined one group of patients who underwent radiotherapy within 75 days from the beginning of treatment as the early RT group, whereas another group of patients who underwent radiotherapy at least 75 days after the beginning of treatment was defined as the late RT group. The response rate (CR + PR) of the early RT group was 92.1% while that of the late RT group was 72.3%. The response rate for radiation therapy thus was significantly better in the early RT group. The 2 and 5-year actuarial survival rates of the early RT group were 22.1% and 9.2%, while those of the late RT group were 19.1% and 8.5%. Then respective median survival times (MST) were 14 months and 13 months. There was no significant difference in survival rates between the two groups. As much as the quality of life is concerned, early RT group would show here better results.

We have exposed an emulsion chamber with an area of 1.22 m 2 on board of the balloon at an atmospheric depth of 8.9 g/cm 2 for 15.8 h, which has been azimuthally controlled within the accuracy of Δφ = 0.5°. With the use of the east-west asymmetry effect of arriving cosmic-ray primaries, we can obtain the energy spectra for individual elements in the kinetic energy range from a few GeV/nucleon up to ∼ 15 GeV/nucleon. We present also the energy spectra obtained by the opening-angle method for the higher energy region, 5–1000 GeV/nucleon, for the elements not lighter than silicon. We find that the energy spectra obtained by the former method continue smoothly to those obtained by the latter, indicating that the energy determination using the opening-angle method is performed correctly. We compare also the present results with those obtained by the previous work. We find that the iron flux is in nice agreement with that obtained by the previous observation, the differential spectral index being constant, ∼ 2.5, up to a few TeV/nucleon, while in the case of the silicon component, it is ∼ 2.7 for 10–1000 GeV/nucleon in this work, significantly harder than the previous one, ∼ 2.9. We also report the flux of the sub-iron component and its abundance ratio to the iron component. We find the abundance ratio of [Z = 21–25]/iron is slightly less than those obtained previously in the higher energy region, ≳ 100 GeV/n.

Purpose: Final goal is to develop a technique to detect the 125I seed and measure its strength during implantation process. This will be a backup tool for QA by offering an additional measurement apart from the pre‐operation measurement. In actual implantation, the speed of the seed varies because it is conducted manually. In order to develop a simple and stable system usable in any speed, this study supposes to use single detector and repeat short‐time measurements. This report summarizes a feasibility test. Methods: The 125I seeds (Oncra Inc. Oncoseed 6711) was moved in speeds up to 200 mm/s by an electric actuator. Its strength was measured with a NaI detector (1″diam. × 1″) set at 170 mm from the needle guiding the seed. The requirement for the counting time was investigated to estimate the strength regardless the seed speed. Results: In the measurement where the seed was set static in needle, the change in counting rate of the NaI detector was 4 % at the 30 mm‐long region along the needle, while the counting rate rapidly decreased outside the region. It is desirable to start‐stop the measurement while the seed is within this region. Assuming 200 mm/s as the maximum speed, 7 to 8 measurements can be performed for the counting time of 20 ms, 3 measurements at 50 ms, 1 measurement at 100 ms. By using the average of the measured results while the seed was within the region, the estimated seed strength agreed within 10 % between the speeds 0 and 200 mm/s at counting time of 100 ms or less. Conclusion: This report shows the feasibility in principle to estimate the 125I seed strength during the implantation operation, regardless the seed velocity.

A woman with multiple bone metastases three years after radical mastectomy for right breast carcinoma was admitted to the Department of Radiology, National Hakodate Hospital. She underwent radiotherapy for the metastasis of the seventh cervical vertebra, and her back pain decreased. Six courses of combination chemotherapy were undertaken using MTX, CPM, 5-FU, VCR and predonine, but her multiple bone metastases progressed. Then, she was treated with chemo-endocrine therapy which consisted of tamoxifen 30 mg daily and CPM 100 mg daily given orally. Two months later, UFT 400 mg daily was administered instead of CPM. This therapy has been effective for 8 years, and she has remained alive and well. On bone scintigram, the abnormal radioisotope uptake almost disappeared. Also, X-ray film showed no osteolytic change and no destruction of bone. These results suggest that it is important to select a suitable combination of drugs for each patient with advanced breast carcinoma.

Radiation pneumonitis and radiation fibrosis are two distinct syndromes with probably different target cells. The ultrastructural changes occur rapidly and current evidence suggests that damage to the type II pneumocyte and the endothelial cell is linked to the pneumonia process than the fibrotic. The fibrosis process may be related to the basement membrane of both endothelial cells and alveolar type I cells. Dose time and volume data for tolerance dose are well documented in animals. Many antineoplastic agents enhances radiation lung damage. The pneumonitis and fibrosis will be discussed.

Paget's disease of the breast is a rare form of breast cancer. Patients with nipple-areolar disease alone and no palpable mass have an excellent prognosis. Although there is some argument about the treatment of this type of Paget's disease, only two reports have been published on the role of conservative treatment. This report discusses a case of limited Paget's disease of the nipple and areola of the breast which was treated by radiation alone without limited surgery.

Late local recurrence of cervical cancer more than 10 years after successful initial treatment is very rare. We now present 17 patients with late local recurrence. Only one patient had undergone primary surgery alone; the other 16 patients had received various types of radiotherapy. All 17 patients received radiotherapy as the second treatment. Local control was achieved in 9 patients, 4 of these survived for more than 5 years after the second treatment. Longterm follow-up for more than 10 years is important for the early detection of late local recurrence.

A woman more than 5 years postmenopausal with right advanced breast cancer (T4, T3, M1, stage IV) was treated with a mild chemo-endocrine therapy. The regimen consisted of diethylstilbestrol diphosphate (Honvan) at 15 mg/day orally and cyclophosphamide at 100 mg/day orally. By the sixth month after administration, both the right breast cancer and multiple lymph node metastases completely disappeared. The change of hormonal therapy from Honvan, as estrogen, to tamoxifen, as antiestrogen, was done 2 years and 9 months after the beginning of initial treatment. The breast cancer recurred 9 months after the change of treatment. At that time, Honvan was again administered instead of tamoxifen. Complete remission was again obtained for 6 months beginning 2 months after the change of drugs, but then the tumor recurred. Although combination chemotherapy was undertaken, the patient died 5 years after initial treatment. These results suggest that chemoendocrine therapy using a low dose of Honvan and cyclophosphamide is effective for advanced breast carcinoma.

Between 1974 and 1980, 61 primary esophageal squamous cell carcinoma were treated by external irradiation combined with additional intracavitary radium therapy. The esophageal primary control rate was 36% (22/61) and the 5-year survival rate was 24.7%. We believe that external radiation therapy followed by additional intracavitary radium irradiation produces good results.

Between 1974 and 1982, 78 primary esophageal squamous cell carcinomas were treated by external irradiation combined with additional intracavitary radium therapy. 50 to 60 Gy were given by external irradiation, and 5 to 20 Gy were delivered on the surface of the esophageal mucosa. The combined dose ranged from TDF 110 to 140 on the esophageal mucosa and TDF 95 to 120 at a depth of 5 mm from the esophageal mucosa. The 5-year survival rate was 19.3% by this combined radiotherapy alone. We conclude that the optimal dose of the combined therapy for esophageal cancer ranges from TDF 95 to 120 at a depth of 5 mm from the esophageal mucosa.

Nineteen patients with newly developed malignant neoplasms following radiotherapy are presented. The primary lesions of 6 patients were tuberculous cervical lymphadenitis, the primary lesions of the other 13 patients were malignant neoplasms. The radiation-induced malignant neoplasms of 15 patients were epithelial, only 4 patients were non-epithelial. The prognosis was not good. However, we think that radiation-induced malignant neoplasms are not highly radioresistant and that the benefits of radiotherapy for malignant neoplasms outweigh the risk of radiation-induced malignant neoplasms.

There has been some controversy concerning dose-time correction in continuous irradiation at low dose rates. We present the results of carcinoma of the tongue in a patient complicated by chronic renal failure, for which he was undergoing hemodialysis three times a week. This patient was treated with a single implant but with a doubling of 137Cs needles for double strength. The actual dose was given in a shorter treatment time than recommended, with the dose-time adjustment following the Paterson-Parker system. The patient has been alive and well for eight years.