50 research outputs found
Updated absolute gravity rate of change associated with glacial isostatic adjustment in Southeast Alaska and its utilization for rheological parameter estimation
In Southeast Alaska (SE-AK), rapid ground uplift of up to 3 cm/yr has been observed associated with post-Little Ice Age glacial isostatic adjustment (GIA). Geodetic techniques such as global navigation satellite system (GNSS) and absolute gravimetry have been applied to monitor GIA since the last 1990s. Rheological parameters for SE-AK were determined from dense GNSS array data in earlier studies. However, the absolute gravity rate of change observed in SE-AK was inconsistent with the ground uplift rate, mainly because few gravity measurements from 2006 to 2008 resulted in imprecise gravity variation rates. Therefore, we collected absolute gravity data at six gravity points in SE-AK every June in 2012, 2013, and 2015, and updated the gravity variation rate by reprocessing the absolute gravity data collected from 2006 to 2015. We found that the updated gravity variation rate at the six gravity points ranged from −2.05 to −4.40 μGal/yr, and its standard deviation was smaller than that reported in the earlier study by up to 88 %. We also estimated the rheological parameters under the assumption of the incompressible Earth to explain the updated gravity variation rate, and their optimal values were determined to be 55 km and 1.2×10¹⁹ Pa s for lithospheric thickness and upper mantle viscosity, respectively. These optimal values are consistent with those independently obtained from GNSS observations, and this fact indicates that absolute gravimetry can be one of the most effective methods in determining sub-surface structural parameters associated with GIA accurately. Moreover, we utilized the gravity variation rates for estimating the ratio of gravity variation to vertical ground deformation at the six gravity points in SE-AK. The viscous ratio values were obtained as −0.168 and −0.171 μGal/mm from the observed data and the calculated result, respectively. These ratios are greater (in absolute) than those for other GIA regions (−0.15 to −0.16 μGal/mm in Antarctica and Fennoscandia), because glaciers in SE-AK have melted more recently than in other regions
コウトウ キョウイク ト ショウガイ キョウイク オ カンガエル International Conference : チイキ シャカイジン オ カツヨウ シタ キョウヨウ キョウイク ノ イッカン トシテノ ニッチュウカン コウリュウ
平成20年度採択の質の高い大学教育改革プログラム「地域社会人を活用した教養教育」では、
地域社会人の勉学に対する高いモチベーションを、共に学ぶ学生が、自ら感じて学び取ることを目的としている。この取り組みを発展させていくために、取り組みに関係する近接する諸外国との意見交換が考えられる。この3カ国では、少子高齢化の問題に関しても共通する課題であり、大学教育に関する課題に関しても共通点が多い。本稿では、今回徳島大学全学共通教育学びのコミュニティー主催で開催した「高等教育と生涯教育に関する国際会議」の概要とその結果得られた成果について様々な角度から考察する
ダイガク キョウイク カイカク ト キョウヨウ キョウイク : チイキ シャカイジン カツヨウ ニヨル チ ノ ジュンカンガタ シャカイ コウチク ニ ムケテ
地域に知の循環型社会を構築することが、少子高齢化の時代を迎えた今日の重要な課題とされている。徳島大学全学共通教育では、今年度から社会性形成科目群を新設した。また、徳島市周辺に在住している地域の社会人の中から、大学教育に造詣の深い方々を大学教育ボランティア(全学共通教育公開授業受講生)として募集し、社会性形成科目群の共創型学習の幾つかの授業に参加していただいた。これらの授業の中で、社会人の参画により、学生のコミュニケーションが円滑に図られる効果があることが明らかになった。また、地域社会人は教員とは異なった視点から意見を述べることが出来るために、新たな視点から授業の展開が出来ることがわかった。学士課程構築を迫られる大学教育の中で、教養科目も変革を迫られている。本稿では、地域社会人が大学教育に関わることの意義と、地域社会人が教養教育を中心とした大学教育改革において、どのような形で貢献しうるのかについて考察する
Spin-gap formation due to spin-Peierls instability in π-orbital-ordered NaO2
We have investigated the low-temperature magnetism of sodium superoxide (NaO2), in which spin, orbital, and lattice degrees of freedom are closely entangled. The magnetic susceptibility shows anomalies at T1 = 220 K and T2 = 190 K, which correspond well to the structural phase transition temperatures, and a sudden decrease below T3 = 34 K. At 4.2 K, the magnetization shows a clear stepwise anomaly around 30 T with a large hysteresis. In addition, the muon spin relaxation experiments indicate no magnetic phase transition down to T = 0.3 K. The inelastic neutron scattering spectrum exhibits magnetic excitation with a finite energy gap. These results confirm that the ground state of NaO2 is a spin-singlet state. To understand this ground state in NaO2, we performed Raman scattering experiments. All the Raman-active libration modes expected for the marcasite phase below T2 are observed. Furthermore, we find that several new peaks appear below T3. This directly evidences the low crystal symmetry, namely, the presence of the phase transition at T3.We conclude that the singlet ground state of NaO2 is due to the spin-Peierls instability
Field measurements of absolute gravity in East Antarctica
This paper reports the results of field-based absolute gravity measurements aimed at detecting gravity change and crustal displacement caused by glacial isostatic adjustment. The project was initiated within the framework of the 53rd Japanese Antarctic Research Expedition (JARE53). Absolute gravity measurements, together with GPS measurements, were planned at several outcrops along the Prince Olav Coast and Sôya Coast of East Antarctica, including at Syowa Station. Since the icebreaker Shirase (AGB 5003) was unable to moor alongside Syowa Station, operations were somewhat restricted during JARE53. However, despite this setback, we were able to complete measurements at two sites: Syowa Station and Langhovde. The absolute gravity value at the Syowa Station IAGBN (A) site, observed using an FG-5 absolute gravimeter (serial number 210; FG-5 #210), was 982 524 322.7±0.1 μGal, and the gravity change rate at the beginning of 2012 was –0.26 μGal∙a-1. An absolute gravity value of 982 535 584.2±0.7 μGal was obtained using a portable A-10 absolute gravimeter (serial number 017; A-10 #017) at the newly located site AGS01 in Langhovde
Personalized prediction of overall survival in patients with AML in non‐complete remission undergoing allo‐HCT
Allogenic hematopoietic stem cell transplantation (allo-HCT) is the standard treatment for acute myeloid leukemia (AML) in non-complete remission (non-CR); however, the prognosis is inconsistent. This study aimed to develop and validate nomograms and a web application to predict the overall survival (OS) of patients with non-CR AML undergoing allo-HCT (cord blood transplantation [CBT], bone marrow transplantation [BMT], and peripheral blood stem cell transplantation [PBSCT]). Data from 3052 patients were analyzed to construct and validate the prognostic models. The common significant prognostic factors among patients undergoing allo-HCT were age, performance status, percentage of peripheral blasts, cytogenetic risk, chemotherapy response, and number of transplantations. The conditioning regimen was a significant prognostic factor only in patients undergoing CBT. Compared with cyclophosphamide/total body irradiation, a conditioning regimen of ≥3 drugs, including fludarabine, with CBT exhibited the lowest hazard ratio for mortality (0.384; 95% CI, 0.266-0.554; p < 0.0001). A conditioning regimen of ≥3 drugs with CBT also showed the best leukemia-free survival among all conditioning regimens. Based on the results of the multivariable analysis, we developed prognostic models showing adequate calibration and discrimination (the c-indices for CBT, BMT, and PBSCT were 0.648, 0.600, and 0.658, respectively). Our prognostic models can help in assessing individual risks and designing future clinical studies. Furthermore, our study indicates the effectiveness of multi-drug conditioning regimens in patients undergoing CBT
Absolute Gravity Measurements and Gravity Changes at Syowa Station, Antarctica
第3回極域科学シンポジウム/第32回極域地学シンポジウム 11月29日(木) 統計数理研究所 3階セミナー
Brief overview of the absolute gravity measurement conducted in JARE53
第3回極域科学シンポジウム/第32回極域地学シンポジウム 11月30日(金) 国立極地研究所 3階ラウン
Absolute gravity observation at the Antarctic Continent with the portable absolute gravimeter A10
第3回極域科学シンポジウム/第32回極域地学シンポジウム 11月29日(木) 統計数理研究所 3階セミナー