AMS 14C Dating of Iron Artifacts: Development and Application

From the 18th International Radiocarbon Conference held in Wellington, New Zealand, September 1-5, 2003.We have developed a prototype carbon extraction system for accelerator mass spectrometry (AMS) radiocarbon dating of archaeological iron remains by combusting them with a RF induction furnace. We have also successfully tested and used a method of carbon extraction from iron using a CuCl2 solution. Modifications to our carbon extraction systems and methods provide us acceptable performances; carbon yield is normally around 80% and the 14C background level is as low as 42-48 ka BP in 14C apparent age. We have also conducted an iron refining experiment to examine the sources for carbon 14C age derived from iron, using established AMS 14C dating and carbon extraction systems. Our refining experiment was conducted on iron slag, which are by-products formed during iron smelting methods in the 7th century AD, and using modern charcoal as fuel. The aim of the experiment was to determine whether original carbon characteristics in the original iron materials would be preserved, or if the carbon signature would be replaced to some degree by the modern charcoal. AMS 14C measurements on the refined iron yielded 14C ages equivalent to those of the modern charcoal fuel. The result indicates that the original carbon signatures in the iron slag from 7th century production was replaced completely by modern carbon used in our experiment. The experiment confirms the assumption that 14C ages on iron products are associated with the fuel source of the iron smelting or refining process. We also report on the dating of iron slag materials excavated from the Gennaitouge iron smelting site, where 14C dates were consistent with the age of the site estimated by archaeological evidence.The Radiocarbon archives are made available by Radiocarbon and the University of Arizona Libraries. Contact [email protected] for further information.Migrated from OJS platform February 202

Basic life support training for single rescuers efficiently augments their willingness to make early emergency calls with no available help: A cross-over questionnaire survey

Background: The aim of this study was to investigate effects of basic life support (BLS) training on willingness of single rescuers to make emergency calls during out-of-hospital cardiac arrests (OHCAs) with no available help from others.Methods: A cross-over questionnaire survey was conducted with two questionnaires. Questionnaires were administered before and after two BLS courses in fire departments. One questionnaire included two scenarios which simulate OHCAs occurring in situations where help from other rescuers is available (Scenario-M) and not available (Scenario-S). The conventional BLS course was designed for multiple rescuers (Course-M), and the other was designed for single rescuers (Course-S).Results: Of 2,312 respondents, 2,218 (95.9%) answered all questions and were included in the analysis. Although both Course-M and Course-S significantly augmented willingness to make early emergency calls not only in Scenario-M but also in Scenario-S, the willingness for Scenario-M after training course was significantly higher in respondents of Course-S than in those of Course-M (odds ratio 1.706, 95% confidential interval 1.301-2.237). Multiple logistic regression analysis for Scenario-M disclosed that post training (adjusted odds ratio 11.6, 95% confidence interval 7.84-18.0), age (0.99, 0.98-0.99), male gender (1.77, 1.39-2.24), prior BLS experience of at least three times (1.46, 1.25-2.59), and time passed since most recent training during 3 years or less (1.80, 1.25-2.59) were independently associated with willingness to make early emergency calls and that type of BLS course was not independently associated with willingness. Therefore, both Course-M and Course-S similarly augmented willingness in Scenario-M. However, in multiple logistic regression analyses for Scenario-S, Course-S was independently associated with willingness to make early emergency calls in Scenario-S (1.26, 1.00-1.57), indicating that Course-S more efficiently augmented willingness. Moreover, post training (2.30, 1.86-2.83) and male gender (1.26, 1.02-1.57) were other independent factors associated with willingness in Scenario-S.Conclusions: BLS courses designed for single rescuers with no help available from others are likely to augment willingness to make early emergency calls more efficiently than conventional BLS courses designed for multiple rescuers. © 2014 Hirose et al

オンデマンド授業「データリテラシー・AI の基礎」における学習行動と教育効果―全学必修の数理・AI・データサイエンス教育―

　武庫川女子大学・同短期大学部では2021 年度後期から「データサイエンス・AI の基礎」を共通教育の全学必修科目として導入した。本稿では，科目導入の経緯や授業計画について述べるとともに，オンデマンド授業における学習行動と教育効果について分析した。その結果，授業内容の理解度は概ね高く，データサイエンスやAI 領域の知識の獲得に加えて，Excel を使用した統計解析スキルを習得できたことがわかった。他方，演習問題の疑問点に迅速に対応できない点が課題として残った

Nasal vaccine delivery attenuates brain pathology and cognitive impairment in tauopathy model mice

Pathological aggregates of tau proteins accumulate in the brains of neurodegenerative tauopathies including Alzheimer’s disease and frontotemporal lobar degeneration (FTLD-tau). Although immunotherapies of these disorders against tau are emerging, it is unknown whether nasal delivery, which offers many benefits over traditional approaches to vaccine administration, is effective or not for tauopathy. Here, we developed vaccination against a secreted form of pathological tau of FTLD-tau using a Sendai virus (SeV) vector infectious to host nasal mucosa, a key part of the immune system. Tau vaccines given as nasal drops induced tissue tau-immunoreactive antibody production and ameliorated cognitive impairment in FTLD-tau model mice. In vivo imaging and postmortem neuropathological assays demonstrated the suppression of phosphorylated tau accumulation, neurotoxic gliosis and neuronal loss in the hippocampus of immunized mice. These findings suggest that nasal vaccine delivery may provide a therapeutic opportunity for a broad range of populations with human tauopathy