On the effects of the atmospheric correction of the GRACE measurements for studies of oceanography

The forthcoming Gravity Recovery and Climate Experience (GRACE) gravity satellite will detect seasonal variations of the gravity field with very high accuracy. Seasonal variations of the mass redistribution would be useful data for several disciplines of geophysics and geodesy, if the seasonal mass variation could be unequivocally separated into its originating components. Seasonal mass variations are mainly provided by the atmosphere, oceans and hydrological processes. The main objective of this study is to analyze the effect of these fluids and/or the processes on the total gravity, focusing on the atmosphere, on the effect of atmospheric correction for studies of oceanography, in order to make use of the highly accurate measurements expected from the GRACE. The study found that a state-of-the-art marine geoid cannot be determined without considering the atmospheric mass redistribution, its effect on the ocean and the ocean´s response to the atmospheric variation

Evaluation of GOCE-based global gravity field models over Japan after the full mission using free-air gravity anomalies and geoid undulations

The performance of Gravity field and steady-state Ocean Circulation Explorer (GOCE) global gravity field models (GGMs), at the end of GOCE mission covering 42 months, is evaluated using geoid undulations and free-air gravity anomalies over Japan, including six sub-regions (Hokkaido, north Honshu, central Honshu, west Honshu, Shikoku and Kyushu). Seventeen GOCE-based GGMs are evaluated and compared with EGM2008. The evaluations are carried out at 150, 180, 210, 240 and 270 spherical harmonics degrees. Results show that EGM2008 performs better than GOCE and related GGMs in Japan and three sub-regions (Hokkaido, central Honshu and Kyushu). However, GOCE and related GGMs perform better than EGM2008 in north Honshu, west Honshu and Shikoku up to degree 240. This means that GOCE data can improve geoid model over half of Japan. The improvement is only evident between degrees 150 and 240 beyond which EGM2008 performs better than GOCE GGMs in all the six regions. In general, the latest GOCE GGMs (releases 4 and 5) perform better than the earlier GOCE GGMs (releases 1, 2 and 3), indicating the contribution of data collected by GOCE in the last months before the mission ended on 11 November 2013. The results indicate that a more accurate geoid model over Japan is achievable, based on a combination of GOCE, EGM2008 and terrestrial gravity data sets

Evaluation of GOCE-based global gravity field models over Japan after the full mission using free-air gravity anomalies and geoid undulations

The performance of Gravity field and steady-state Ocean Circulation Explorer (GOCE) global gravity field models (GGMs), at the end of GOCE mission covering 42 months, is evaluated using geoid undulations and free-air gravity anomalies over Japan, including six sub-regions (Hokkaido, north Honshu, central Honshu, west Honshu, Shikoku and Kyushu). Seventeen GOCE-based GGMs are evaluated and compared with EGM2008. The evaluations are carried out at 150, 180, 210, 240 and 270 spherical harmonics degrees. Results show that EGM2008 performs better than GOCE and related GGMs in Japan and three sub-regions (Hokkaido, central Honshu and Kyushu). However, GOCE and related GGMs perform better than EGM2008 in north Honshu, west Honshu and Shikoku up to degree 240. This means that GOCE data can improve geoid model over half of Japan. The improvement is only evident between degrees 150 and 240 beyond which EGM2008 performs better than GOCE GGMs in all the six regions. In general, the latest GOCE GGMs (releases 4 and 5) perform better than the earlier GOCE GGMs (releases 1, 2 and 3), indicating the contribution of data collected by GOCE in the last months before the mission ended on 11 November 2013. The results indicate that a more accurate geoid model over Japan is achievable, based on a combination of GOCE, EGM2008 and terrestrial gravity data sets

Impact of satellite gravity missions on glaciology and Antarctic Earth sciences

Satellite gravity missions in the 21st Century are expected to be beneficial to multi-disciplinary scientific objectives. Especially, the Gravity Recovery And Climate Experiment (GRACE) and its follow-on missions will provide not only data for precise gravity mapping but also time series of global gravity field coefficients at intervals of about 15 days to two months. These data are precise enough to reveal the temporal variations of the gravity fields due to mass redistribution in and on the Earth. From the viewpoint of Earth sciences in the Antarctic region, the data are expected to contribute to studies of ice sheet mass balance and postglacial rebound as well as other geodetic and geophysical problems. These issues have been mainly investigated based on the degree variance analyses of the gravity field so far. In this paper, we briefly review the gravity mission data from the viewpoint of along track geoid height variations which are more direct results of the mass variations, and then discuss some of the issues related to in-situ observations

Calibration of the superconducting gravimeter TT70 #016 at Syowa Station by parallel observation with the absolute gravimeter FG5 #203

For the purpose ofcalibration ofthe superconducting gravimeter model TT70 #016 at Syowa Station,Antarctica,we carried out parallel observations with the absolute gravimeter FG5 #203 from December 29, 2000 to January 25, 2001. During the FG5 measurements,the laser stability was sometimes not good and this caused irregular data.We carefully examined the relation between laser stability and gravity values,and took it into account for the removal of abnormal data.We applied linear regression to the selected SG and FG /data set,and obtained the value of -58.168 μGal/V to an accuracy of 0.10% for the scale factor of TT 70 #016.The difference of the obtained scale factor from the previous value of -57.965 μGal/V is about 0.35%

Efficacy and safety of amrubicin hydrochloride for treatment of relapsed small cell lung cancer

Long-term survival is quite uncommon in refractory small cell lung cancer (SCLC) patients, with less than 25% of patients with limited-stage disease and 1%–2% of patients with extensive-stage disease remaining alive at five years. Recent clinical studies have demonstrated the promising efficacy of amrubicin for patients with relapsed SCLC. This review presents the results of clinical studies showing the efficacy and safety of amrubicin for the treatment of relapsed SCLC. Amrubicin is a synthetic anthracycline agent with a similar structure to doxorubicin, in which the hydroxyl group at position 9 in amrubicin is replaced by an amino group to enhance efficacy. It is converted to an active metabolite, amrubicinol, which is 5–54 times more active than amrubicin. Amrubicin and amrubicinol are inhibitors of DNA topoisomerase II, exerting their cytotoxic effects by stabilizing a topoisomerase II-mediated cleavable complex. The toxicity of amrubicin is similar to that of doxorubicin, although amrubicin shows almost no cardiotoxicity. In the relevant trials, amrubicin was administered intravenously at a dose of 35–40 mg/m2 on days 1–3 every three weeks. The response rate was 34%–52% and median survival times were 8.1–12.0 months. Common hematologic toxicities included neutropenia, leucopenia, anemia, thrombocytopenia, and febrile neutropenia. Nonhematologic adverse events included Grade 3–4 anorexia, asthenia, hyponatremia, and nausea. The results of the studies which demonstrated the efficacy of monotherapy for relapsed SCLC involved mainly Japanese patients. Therefore, it is necessary to conduct more clinical studies in non-Japanese patients to confirm the efficacy of amrubicin

Installation of the superconducting gravimeter CT(#043) at Syowa Station, Antarctica

During the wintering period of the 44th Japanese Antarctic Research Expedition (JARE-44: February 2003 to January 2004), a new superconducting gravimeter CT(#043) with a cryocooler was installed and tested to replace the former TT70(#016) at Syowa Station, Antarctica. The CT(#043) has design sensitivity of 1nGal (1×10^(-11)m/s^2) to study the Earth\u27s dynamics in tidal and longer-period bands. A new type of diaphragm was used to effectively isolate the vibration from the refrigerator cold-head and to prevent solid air contamination from entering the Dewar. A real-time remote monitoring system including a Web camera for diagnostics from Japan has also been installed