Physical and chemical weathering properties of till deposits in the Sør Rondane Mountains, Dronning Maud Land (II)

第6回極域科学シンポジウム[OG] 地圏11月16日（月）　国立極地研究所３階セミナー

ヒガシ ドロンイングモードランド,セール・ロンダーネ サンチ チガク チョウサタイ ホウコク 20112012(JARE-53)

第53次日本南極地域観測隊(JARE-53)夏隊の一部は,2011-2012年の夏期に,東ドロンイングモードランドのセール・ロンダーネ山地において地形・測地調査を実施した.また,この調査はBelgian Antarctic Research Expedition (BELARE)とInternational Polar Foundation(IPF)のサポートによって実施された.本調査のメンバー構成は,地形調査担当3名,測地担当1名,およびフィールドアシスタント1名である.南極への移動経路は往復路ともにドロンイングモードランド航空ネットワーク(DROMLAN)を利用し,空路ケープタウンからノボラザレフスカヤ基地滑走路を経由して現地入りした.調査地域はセール・ロンダーネ山地の西部および中部とした.本稿では調査,設営,気象をはじめとする本調査隊の行動全般について報告する.Geomorphologic and geodetic field surveys were carried out in the Sør Rondane Mountains, East Dronning Maud Land, Antarctica, during the 2011-2012 summer season as part of the 53rd Japanese Antarctic Research Expedition (JARE-53). The field party consisted of three geomorphologists, one geodesist, and one field assistant. The expedition was supported by the Belgian Antarctic Research Expedition (BELARE) and the International Polar Foundation (IPF). Dronning Maud Land Air Network (DROMLAN) provided air transport from Cape Town, South Africa to the Sør Rondane Mountains via Novolazarevskaya Airbase. The survey areas were the central and western parts of the Sør Rondane Mountains. This report summarizes the field expedition in terms of operations, logistics, and weather records

Decline in subarachnoid haemorrhage volumes associated with the first wave of the COVID-19 pandemic

BACKGROUND: During the COVID-19 pandemic, decreased volumes of stroke admissions and mechanical thrombectomy were reported. The study\u27s objective was to examine whether subarachnoid haemorrhage (SAH) hospitalisations and ruptured aneurysm coiling interventions demonstrated similar declines. METHODS: We conducted a cross-sectional, retrospective, observational study across 6 continents, 37 countries and 140 comprehensive stroke centres. Patients with the diagnosis of SAH, aneurysmal SAH, ruptured aneurysm coiling interventions and COVID-19 were identified by prospective aneurysm databases or by International Classification of Diseases, 10th Revision, codes. The 3-month cumulative volume, monthly volumes for SAH hospitalisations and ruptured aneurysm coiling procedures were compared for the period before (1 year and immediately before) and during the pandemic, defined as 1 March-31 May 2020. The prior 1-year control period (1 March-31 May 2019) was obtained to account for seasonal variation. FINDINGS: There was a significant decline in SAH hospitalisations, with 2044 admissions in the 3 months immediately before and 1585 admissions during the pandemic, representing a relative decline of 22.5% (95% CI -24.3% to -20.7%, p\u3c0.0001). Embolisation of ruptured aneurysms declined with 1170-1035 procedures, respectively, representing an 11.5% (95%CI -13.5% to -9.8%, p=0.002) relative drop. Subgroup analysis was noted for aneurysmal SAH hospitalisation decline from 834 to 626 hospitalisations, a 24.9% relative decline (95% CI -28.0% to -22.1%, p\u3c0.0001). A relative increase in ruptured aneurysm coiling was noted in low coiling volume hospitals of 41.1% (95% CI 32.3% to 50.6%, p=0.008) despite a decrease in SAH admissions in this tertile. INTERPRETATION: There was a relative decrease in the volume of SAH hospitalisations, aneurysmal SAH hospitalisations and ruptured aneurysm embolisations during the COVID-19 pandemic. These findings in SAH are consistent with a decrease in other emergencies, such as stroke and myocardial infarction

The Phosphorylation-Dependent Regulation of Mitochondrial Proteins in Stress Responses

To maintain cellular homeostasis, cells are equipped with precise systems that trigger the appropriate stress responses. Mitochondria not only provide cellular energy but also integrate stress response signaling pathways, including those regulating cell death. Several lines of evidence suggest that the mitochondrial proteins that function in this process, such as Bcl-2 family proteins in apoptosis and phosphoglycerate mutase family member 5 (PGAM5) in necroptosis, are regulated by several kinases. It has also been suggested that the phosphorylation-dependent regulation of mitochondrial fission machinery, dynamin-related protein 1 (Drp1), facilitates appropriate cellular stress responses. However, mitochondria themselves are also damaged by various stresses. To avoid the deleterious effects exerted by damaged mitochondria, cells remove these mitochondria in a selective autophagic degradation process called mitophagy. Interestingly, several kinases, such as PTEN-induced putative kinase 1 (PINK1) in mammals and stress-responsive mitogen-activated protein (MAP) kinases in yeast, have recently been shown to be involved in mitophagy. In this paper, we focus on the phosphorylation-dependent regulation of mitochondrial proteins and discuss the roles of this regulation in the mitochondrial and cellular stress responses

Report on geomorphologic and geodesic field surveys in the Sor Rondane Mountains, Eastern Dronning Maud Land, 2011-2012 (JARE-53)

Geomorphologic and geodetic field surveys were carried out in the Sor Rondane Mountains, East Dronning Maud Land, Antarctica, during the 2011-2012 summer season as part of the 53rd Japanese Antarctic Research Expedition (JARE-53). The field party consisted of three geomorphologists, one geodesist, and one field assistant. The expedition was supported by the Belgian Antarctic Research Expedition (BELARE) and the International Polar Foundation (IPF). Dronning Maud Land Air Network (DROMLAN) provided air transport from Cape Town, South Africa to the Sor Rondane Mountains via Novolazarevskaya Airbase. The survey areas were the central and western parts of the Sor Rondane Mountains. This report summarizes the field expedition in terms of operations, logistics, and weather records

An Argon-Ion-Induced Pale Green Mutant of Arabidopsis Exhibiting Rapid Disassembly of Mesophyll Chloroplast Grana

Argon-ion beam is an effective mutagen capable of inducing a variety of mutation types. In this study, an argon ion-induced pale green mutant of was isolated and characterized. The mutant, designated Ar50-33-pg1, exhibited moderate defects of growth and greening and exhibited rapid chlorosis in photosynthetic tissues. Fluorescence microscopy confirmed that mesophyll chloroplasts underwent substantial shrinkage during the chlorotic process. Genetic and whole-genome resequencing analyses revealed that Ar50-33-pg1 contained a large 940 kb deletion in chromosome V that encompassed more than 100 annotated genes, including 41 protein-coding genes such as /, , and . One of the deleted genes, , for a thylakoid membrane-localized metalloprotease, was the major contributory gene responsible for the pale mutant phenotype. Both an mutant and F progeny of an Ar50-33-pg1 × cross-exhibited chlorotic phenotypes similar to those of Ar50-33-pg1. Furthermore, ultrastructural analysis of mesophyll cells revealed that Ar50-33-pg1 and initially developed wild type-like chloroplasts, but these were rapidly disassembled, resulting in thylakoid disorganization and fragmentation, as well as plastoglobule accumulation, as terminal phenotypes. Together, these data support the utility of heavy-ion mutagenesis for plant genetic analysis and highlight the importance of in the structural maintenance of grana in mesophyll chloroplasts