AbstractTo enable precise assessment of health impacts following a nuclear power plant accident, extensive and detailed data on environmental radiation levels are needed. This study was undertaken to investigate the air and the soil radiation levels using a car-borne survey on the main island of Taiwan where no extensive environmental radiation distribution survey had been conducted before. The mean air absorbed dose rate on this island was 57 ± 10 nGy h−1. The measured dose rate distribution varied depending on the geology of the soils, and ranged from 22 to 113 nGy h−1. The mean radiation level in soil was 539 ± 124 Bq kg−1 for 40K, 23 ± 8 Bq kg−1 for 238U and 41 ± 22 Bq kg−1 for 232Th. The air absorbed dose rate (58 nGy h−1) calculated from these data of mean radiation level in soil was comparable to that determined by the car-borne survey method. Thus, this study yielded detailed data on air absorbed dose rate depending primarily on the geology of the soils on the main island of Taiwan.

2020-10-01·Environmental Pollution2区 · 环境科学与生态学

Plutonium isotopes in Northern Xinjiang, China: Level, distribution, sources and their contributions

2区 · 环境科学与生态学

Article

作者: Qiao, Jixin ; Hou, Xiaolin ; Zhao, Xue

Plutonium in the environment has drawn significant attentions due to its radiotoxicity in high concentration and source term linked with nuclear accidents and contaminations. The isotopic ratio of plutonium is source dependent and can be used as a fingerprint to discriminate the sources of radioactive contaminant. ²³⁹Pu, ²⁴⁰Pu and ¹³⁷Cs in surface soil and soil cores collected from Northern Xinjiang were determined in this work. The concentrations of ^239,240Pu and ¹³⁷Cs are in the range of 0.06-1.20 Bq kg^-1, and <1.0-31.4 Bq kg^-1 (decay corrected to Sep. 2017), respectively, falling in the ranges of global fallout in this latitude zone. The ²⁴⁰Pu/²³⁹Pu atomic ratios of 0.118-0.209 and ^239,240Pu/¹³⁷Cs activity ratios of 0.039-0.215 were measured. Among the investigated sites, distinctly lower ²⁴⁰Pu/²³⁹Pu atomic ratios of 0.118-0.133 and higher ^239,240Pu/¹³⁷Cs activity ratios of 0.065-0.215 compared to the global fallout values were observed in the northwest part, indicating a significant contribution from other source besides the global fallout. This extra source is mainly attributed to the releases of atmospheric nuclear weapons testing at Semipalatinsk Nuclear Test Site, which was transported by the west and northwest wind through the river valley among mountains in this region. This contribution is estimated to account for 28-43% of the global fallout in the northwest part of Northern Xinjiang. The contribution from the Chinese atmospheric nuclear weapons testing to this region is negligible due to the lack of appropriate wind direction to transport the radioactive releases to this region.

2020-01-01·Science of The Total Environment2区 · 环境科学与生态学

Activity concentrations of 137Cs, 40K, and 210Pb radionuclides in selected medicinal herbs from Central Serbia and their effective dose due to ingestion

2区 · 环境科学与生态学

Article

作者: Kandić, Aleksandar ; Kandić, Irina ; Čeliković, Igor ; Gavrilović, Milan ; Janaćković, Peđa

Specific activity of ¹³⁷Cs, ⁴⁰K, and ²¹⁰Pb radionuclides in fifteen selected medicinal herbs from three locations in Central Serbia (two mountains, Kopaonik and Zlatar, and a valley, Sokobanja) was measured using two semiconductor HPGe spectrometer systems. The obtained values are in intervals (<0.3 ÷ 9.7) Bq/kg, (<0.2 ÷ 24.7) Bq/kg, and (<0.2 ÷ 5.7) Bq/kg for ¹³⁷Cs; in intervals (125 ÷ 1100) Bq/kg, (104 ÷ 872) Bq/kg, and (103 ÷ 954) Bq/kg for ⁴⁰K, and in intervals (3.6 ÷ 49.0) Bq/kg, (3.9 ÷ 57.9) Bq/kg, and (2.8 ÷ 103) Bq/kg for ²¹⁰Pb, for herbs from Kopaonik, Sokobanja and Zlatar, respectively. The highest activity measured in individual herbs was: 24.7 Bq/kg for ¹³⁷Cs (Sokobanja valley), 1100 Bq/kg for ⁴⁰K (Mt. Kopaonik) and 103 Bq/kg for ²¹⁰Pb (Mt. Zlatar). The corresponding individual annual effective doses due to ingestion calculated from the measured activity concentrations, of the radionuclides are: in intervals (<1.7 ÷ 82.9) nSv, (<1.4 ÷ 211) nSv, and (<1.1 ÷ 48.7) nSv for ¹³⁷Cs; in intervals (0.76 ÷ 4.5) μSv, (0.64 ÷ 4.4) μSv, and (0.63 ÷ 4.9) μSv for ⁴⁰K, and in intervals (1.1 ÷ 18.2) μSv, (1.3 ÷ 21.6) μSv, (0.9 ÷ 38.3) μSv for ²¹⁰Pb, respectively. The specific activity concentration values of ¹³⁷Cs and ⁴⁰K obtained for the investigated herbs are similar to the literature data, while no information was found in literature about specific activity concentration of ²¹⁰Pb. The all values obtained for individual annual effective dose due to ingestion are less than 100 μSv, which means that the daily use of 200 mL of herbal infusion during a year made from the investigated herbs does not represent a radiological risk for health. However, a high individual annual effective dose of ingestion of ²¹⁰Pb obtained for some herbs indicate that their consumption in larger amounts 2-3 cups of infusion daily over a year could make the dose to exceed the recommended level, and points to necessity for extensive investigation of ²¹⁰Pb activity concentration worldwide.

项与 BQ-Complex 相关的新闻（医药）

2022-12-20

·生物谷

Cell：奥密克戎BQ和XBB逃逸能力，强到令人担忧

总的来说，这项研究结果表明，奥密克戎BQ和XBB对当前的新冠疫苗（包括针对突变株的二价mRNA疫苗）构成了严重威胁，而且目前所有的治疗性单克隆抗体也对它们无效。最近，新冠病毒奥密克戎突变株新亚型BQ和XBB正在迅速传播。这可能是由于它们额外的刺突蛋白突变导致对疫苗接种产生的中和抗体具有更强的逃逸能力。自去年冬天以来，奥密克戎一直是全世界范围内的主要流行株，其中BA.5是一种高度传染性的奥密克戎亚型，BA.5在今年夏秋之际引发了大量新增病例。近期，美国新增的COVID-19病例中约68%由BQ.1或BQ.1.1这两种奥密克戎新亚型引起的。而在新加坡、孟加拉国和印度在内的亚洲国家，奥密克戎新亚型XBB正在掀起了新的感染浪潮。美国哥伦比亚大学何大一团队等在 Cell 期刊发表了题为：Alarming antibody evasion properties of rising SARS-CoV-2 BQ and XBB subvariants 的研究论文。该研究证实了BQ.1、BQ.1.1、XBB和XBB.1这些奥密克戎亚型具有目前已知最强的逃逸中和抗体的能力，因此，它们可能因为在逃逸中和抗体方面的优势而在人群中占据主导地位，成为新的主要流行株。 BQ和XBB的核心突变位点这项研究显示，新冠疫苗及感染者血清对BQ.1、BQ.1.1、XBB和XBB.1的中和能力明显下降，包括WA1/BA.5二价mRNA疫苗加强的个体的血清。针对BQ和XBB的中和滴度分别降低了13-81倍和66-155倍，这远远超过之前观察到的任何新冠突变株的情况。而能够中和早期奥密克戎的单克隆抗体对这几个奥密克戎亚型基本无效。总的来说，这项研究结果表明，奥密克戎BQ和XBB对当前的新冠疫苗（包括针对突变株的二价mRNA疫苗）构成了严重威胁，而且目前所有的治疗性单克隆抗体也对它们无效。因此，BQ和XBB可能因为在逃逸中和抗体方面的优势而在人群中占据主导地位，成为新的主要流行株。关于何大一何大一，1952年11月3日出生于中国台湾，12岁时随家人移民到美国加州洛杉矶市。1970年，何大一考入美国麻省理工学院，并在四年后以第一名的优异成绩毕业，后在哈佛大学获得医学博士学位。 1981年6月5日，美国疾控中心发布了5例艾滋病病例报告，这也是世界上首次发现艾滋病。此时的何大一在西奈医疗中心当实习医生，他接触到了这一批最早的艾滋病病例。此后何大一致力于艾滋病研究，成为世界上最早认识到艾滋病是由病毒引起的科学家之一，也成为首先阐明艾滋病病毒复制多样性的科学家之一。 1996年，面对艾滋病患者频频出现的耐药性问题，何大一提出了“鸡尾酒疗法”，将多种抗艾滋病药物组成一个组合，将蛋白酶抑制剂药物和核苷类逆转录酶抑制剂及非核苷类逆转录酶抑制剂药物组合使用，相较单一药物，能更有效地治疗艾滋病，且更不易出现耐药性。鸡尾酒疗法自1996年使用以来，有效降低了艾滋病人死亡率，目前仍是最常用、效果最显著的艾滋病治疗方法之一。由于“鸡尾酒疗法”对于艾滋病治疗的卓越贡献，何大一于1996年入选美国《时代》周刊年度人物，2010年，被《时代》周刊称为“打败艾滋病的人”。