Deep ice coring at Dome Fuji Station, Antarctica

Deep ice coring was carried out at Dome Fuji Station, Antarctica in 1995 and 1996 following a pilot borehole drilled and cased with FRP pipes in 1993,and reached 2503.52m in December 1996. Total numbers of ice coring runs below the pilot borehole and chip collection were 1369 and 837 respectively. The mean coring depths per run and per day were 1.75m and 8.21m respectively. We report the outline of the coring operation, the system, coring method, and troubles encountered during the coring work

ナンキョク ドーム フジ カンソク キョテン ニオケル ヒョウソウ シンソウ コア クッサク

南極ドームふじ観測拠点において, 1993年パイロット孔の掘削とケーシングが行われたのに引き続き, 1995年から2カ年にわたり本格的な深層コア掘削が進められ, 1996年12月に2503.52m深に達した。本掘削におけるコア掘削の総回数は1369回, チップ回収作業は837回に及んだ。1回の平均コア掘削長は1.75m, 一日の平均コア掘削長は8.21mであった。本報告では, 現地で使用された掘削システムの概要とともに, 掘削の経過, および掘削の方法を述べるとともに, 掘削中に生じたさまざまなトラブルについても取られたその対策とともに報告し, 併せて今後の課題を示した。Deep ice coring was carried out at Dome Fuji Station, Antarctica in 1995 and 1996 following a pilot borehole drilled and cased with FRP pipes in 1993,and reached 2503.52m in December 1996. Total numbers of ice coring runs below the pilot borehole and chip collection were 1369 and 837 respectively. The mean coring depths per run and per day were 1.75m and 8.21m respectively. We report the outline of the coring operation, the system, coring method, and troubles encountered during the coring work

Risk for Major Bleeding in Patients Receiving Ticagrelor Compared With Aspirin After Transient Ischemic Attack or Acute Ischemic Stroke in the SOCRATES Study (Acute Stroke or Transient Ischemic Attack Treated With Aspirin or Ticagrelor and Patient Outcomes)

International audienc

Risk for Major Bleeding in Patients Receiving Ticagrelor Compared With Aspirin After Transient Ischemic Attack or Acute Ischemic Stroke in the SOCRATES Study (Acute Stroke or Transient Ischemic Attack Treated With Aspirin or Ticagrelor and Patient Outcomes)

Abstract: Background: Patients with minor acute ischemic stroke or transient ischemic attack are at high risk for subsequent stroke, and more potent antiplatelet therapy in the acute setting is needed. However, the potential benefit of more intense antiplatelet therapy must be assessed in relation to the risk for major bleeding. The SOCRATES trial (Acute Stroke or Transient Ischemic Attack Treated With Aspirin or Ticagrelor and Patient Outcomes) was the first trial with ticagrelor in patients with acute ischemic stroke or transient ischemic attack in which the efficacy and safety of ticagrelor were compared with those of aspirin. The main safety objective was assessment of PLATO (Platelet Inhibition and Patient Outcomes)\u2013defined major bleeds on treatment, with special focus on intracranial hemorrhage (ICrH). Methods: An independent adjudication committee blinded to study treatment classified bleeds according to the PLATO, TIMI (Thrombolysis in Myocardial Infarction), and GUSTO (Global Use of Strategies to Open Occluded Coronary Arteries) definitions. The definitions of ICrH and major bleeding excluded cerebral microbleeds and asymptomatic hemorrhagic transformations of cerebral infarctions so that the definitions better discriminated important events in the acute stroke population. Results: A total of 13 130 of 13 199 randomized patients received at least 1 dose of study drug and were included in the safety analysis set. PLATO major bleeds occurred in 31 patients (0.5%) on ticagrelor and 38 patients (0.6%) on aspirin (hazard ratio, 0.83; 95% confidence interval, 0.52\u20131.34). The most common locations of major bleeds were intracranial and gastrointestinal. ICrH was reported in 12 patients (0.2%) on ticagrelor and 18 patients (0.3%) on aspirin. Thirteen of all 30 ICrHs (4 on ticagrelor and 9 on aspirin) were hemorrhagic strokes, and 4 (2 in each group) were symptomatic hemorrhagic transformations of brain infarctions. The ICrHs were spontaneous in 6 and 13, traumatic in 3 and 3, and procedural in 3 and 2 patients on ticagrelor and aspirin, respectively. In total, 9 fatal bleeds occurred on ticagrelor and 4 on aspirin. The composite of ICrH or fatal bleeding included 15 patients on ticagrelor and 18 on aspirin. Independently of bleeding classification, PLATO, TIMI, or GUSTO, the relative difference between treatments for major/severe bleeds was similar. Nonmajor bleeds were more common on ticagrelor. Conclusions: Antiplatelet therapy with ticagrelor in patients with acute ischemic stroke or transient ischemic attack showed a bleeding profile similar to that of aspirin for major bleeds. There were few ICrHs. Clinical Trial Registration: URL: http://www.clinicaltrials.gov. Unique identifier: NCT01994720.Abstract: BACKGROUND: Patients with minor acute ischemic stroke or transient ischemic attack are at high risk for subsequent stroke, and more potent antiplatelet therapy in the acute setting is needed. However, the potential benefit of more intense antiplatelet therapy must be assessed in relation to the risk for major bleeding. The SOCRATES trial (Acute Stroke or Transient Ischemic Attack Treated With Aspirin or Ticagrelor and Patient Outcomes) was the first trial with ticagrelor in patients with acute ischemic stroke or transient ischemic attack in which the efficacy and safety of ticagrelor were compared with those of aspirin. The main safety objective was assessment of PLATO (Platelet Inhibition and Patient Outcomes)-defined major bleeds on treatment, with special focus on intracranial hemorrhage (ICrH). METHODS: An independent adjudication committee blinded to study treatment classified bleeds according to the PLATO, TIMI (Thrombolysis in Myocardial Infarction), and GUSTO (Global Use of Strategies to Open Occluded Coronary Arteries) definitions. The definitions of ICrH and major bleeding excluded cerebral microbleeds and asymptomatic hemorrhagic transformations of cerebral infarctions so that the definitions better discriminated important events in the acute stroke population. RESULTS: A total of 13 130 of 13 199 randomized patients received at least 1 dose of study drug and were included in the safety analysis set. PLATO major bleeds occurred in 31 patients (0.5%) on ticagrelor and 38 patients (0.6%) on aspirin (hazard ratio, 0.83; 95% confidence interval, 0.52-1.34). The most common locations of major bleeds were intracranial and gastrointestinal. ICrH was reported in 12 patients (0.2%) on ticagrelor and 18 patients (0.3%) on aspirin. Thirteen of all 30 ICrHs (4 on ticagrelor and 9 on aspirin) were hemorrhagic strokes, and 4 (2 in each group) were symptomatic hemorrhagic transformations of brain infarctions. The ICrHs were spontaneous in 6 and 13, traumatic in 3 and 3, and procedural in 3 and 2 patients on ticagrelor and aspirin, respectively. In total, 9 fatal bleeds occurred on ticagrelor and 4 on aspirin. The composite of ICrH or fatal bleeding included 15 patients on ticagrelor and 18 on aspirin. Independently of bleeding classification, PLATO, TIMI, or GUSTO, the relative difference between treatments for major/severe bleeds was similar. Nonmajor bleeds were more common on ticagrelor. CONCLUSIONS: Antiplatelet therapy with ticagrelor in patients with acute ischemic stroke or transient ischemic attack showed a bleeding profile similar to that of aspirin for major bleeds. There were few ICrHs