radiation effects

辐射效应
  • 文章类型: Journal Article
    传统的双指数瞬态电流模型(DE模型)可以过驱动电路的问题,这导致逻辑单元的软错误率的高估,已解决。我们的工作使用了一种新的精确模型来预测软错误率,从而使软错误率更接近实际。选择分段双指数瞬态电流模型(PDE模型),使用布局感知单事件多瞬态软错误率计算工具(LA-SEMT-SER工具)反映模型的准确性。该模型可以分段地表征瞬态电流脉冲并且限制峰值电流幅度不超过传导电流。TCAD模型由28nm工艺库和单元布局构成。对器件的传递特性曲线进行了标定,并进行功能时序验证,以确保TCAD模型的准确性。实验结果表明,PDE模型不仅在器件单事件瞬态电流建模上比DE模型更符合TCAD仿真,而且,基于PDE模型的LA-SEMT-SER工具计算的SER比基于DE模型的LA-SEMT-SER工具计算的SER具有更小的误差。
    The problem that the conventional double-exponential transient current model (DE model) can overdrive the circuit, which leads to the overestimation of the soft error rate of the logic cell, is solved. Our work uses a new and accurate model for predicting the soft error rate that brings the soft error rate closer to the actual. The piecewise double-exponential transient current model (PDE model) is chosen, and the accuracy of the model is reflected using the Layout Awareness Single Event Multi Transients Soft Error Rate Calculation tool (LA-SEMT-SER tool). The model can characterize transient current pulses piecewise and limit the peak current magnitude to not exceed the conduction current. TCAD models are constructed from 28 nm process library and cell layouts. The transfer characteristic curves of devices are calibrated, and functional timing verification is performed to ensure the accuracy of the TCAD model. The experimental results show that the PDE model is not only more consistent with TCAD simulation than the DE model in modeling the single event transient currents of the device, but also that the SER calculated by the LA-SEMT-SER tool based on the PDE model has a smaller error than the SER calculated by the LA-SEMT-SER tool based on the DE model.
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  • 文章类型: Journal Article
    本文提出了一种创新的技术,高级电气参数预测器,基于机器学习方法预测电子元器件在辐射作用下的退化。术语退化是指电子部件的电参数随照射剂量变化的方式。此方法由两个连续步骤组成,分别定义为“识别数据库中的降解模式”和“在没有任何辐照的情况下对新样品进行降解预测”。该技术可以在称为“纯数据驱动”和“基于模型”的两种不同方法下使用。在本文中,对于双极晶体管,显示了高级电气参数预测器的使用,但是该方法足够通用,可以应用于任何其他组件。
    This paper presents an innovative technique, Advanced Predictor of Electrical Parameters, based on machine learning methods to predict the degradation of electronic components under the effects of radiation. The term degradation refers to the way in which electrical parameters of the electronic components vary with the irradiation dose. This method consists of two sequential steps defined as \'recognition of degradation patterns in the database\' and \'degradation prediction of new samples without any kind of irradiation\'. The technique can be used under two different approaches called \'pure data driven\' and \'model based\'. In this paper, the use of Advanced Predictor of Electrical Parameters is shown for bipolar transistors, but the methodology is sufficiently general to be applied to any other component.
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  • 文章类型: Journal Article
    在反应堆环境下,用于氢同位素存储的锆三体的性能发生了显着变化。这可以归因于各种辐射诱导的位错的形成。为了帮助获得洞察力,分子动力学模拟已用于研究含不同类型边缘位错的锆中的氢同位素种群。我们的研究表明,氢同位素浓度在位错核的拉伸侧附近最高,并且根据位错类型而变化。氢同位素浓度的增加可以用玻尔兹曼方程解释,该方程基于使用膨胀体积和压力场的计算,显著降低了计算成本。引人注目的是,因为位错压缩区域的氢同位素耗尽,发现整体的氢同位素含量是不变的位错形成。这些结果与先前的观点相反,即位错捕获效应增加了氢同位素溶解度,并提供了对反应堆条件下氢同位素压力变化的理解。通过阐明位错对氢同位素储存性能的影响,这项研究为优化锆三体在核应用中提供了见解。并有助于氢同位素储存材料的进步。
    Performance of zirconium tritides used for hydrogen isotope storage is significantly changed under reactor environments. This can be attributed to the formation of various radiation-induced dislocations. To help gain insight, molecular dynamics simulations have been employed to investigate hydrogen isotope population in zirconium containing different types of edge dislocations. Our studies reveal that hydrogen isotope concentration is highest near the tensile side of dislocation cores and varies based on dislocation type. This increase in hydrogen isotope concentration can be explained by the Boltzmann equation based on calculations using swelling volume and pressure field, with significantly reduced computational cost. Strikingly, because hydrogen isotope in the compressive regions of dislocations is depleted, the overall hydrogen isotope content is found to be unchanged by dislocation formation. These results counter the previous view that the dislocation trapping effect increases hydrogen isotope solubility and provide an understanding of changes in hydrogen isotope pressure under reactor conditions. By elucidating the impact of dislocations on hydrogen isotope storage performance, this research offers insights for optimizing zirconium tritides in nuclear applications. and contributes to the advancement of hydrogen isotope storage materials.
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  • 文章类型: Journal Article
    背景:科学文献中出现了关于暴露于电离辐射的介入医生的脑肿瘤病例的轶事报道。为了响应这个警报,引线帽的几种设计已经在商业上可用。然而,报告的疗效结果不一致.
    目的:合成,通过对文献的系统回顾,降低辐射水平的能力由辐射衰减设备(RAD)在介入医生的大脑水平。
    方法:进行了系统评价,包括以下数据库:MEDLINE,Scopus,EBSCO,科学直接,Cochrane控制试验登记册(中央),WOS,世卫组织国际临床试验登记册,Scielo和谷歌学者,考虑1990年1月至2022年5月评估RAD在实验或临床环境中疗效的原始研究。数据选择和提取一式三份,与第四作者解决差异。
    结果:从数据库中最初选择的总共373项研究中纳入了20篇文章。从这些,在临床条件下进行了12项研究,包括3801个透视引导程序,在实验条件下使用幻影进行了十项研究,共有88个程序,我们使用数值计算进行了4项研究,共63项手术.本综述中分析的上限提供的衰减和有效性从12.3%到99.9%不等,y分别为4.9%至91%。
    结论:发现RAD可能提供辐射防护,但是在屏蔽中发现了高度的异质性。这表明需要根据实践对上限效率进行本地评估。
    Background.Anecdotal reports are appearing in the scientific literature about cases of brain tumors in interventional physicians who are exposed to ionizing radiation. In response to this alarm, several designs of leaded caps have been made commercially available. However, the results reported on their efficacy are discordant.Objective.To synthesize, by means of a systematic review of the literature, the capacity of decreasing radiation levels conferred by radiation attenuating devices (RADs) at the cerebral level of interventional physicians.Methodology.A systematic review was performed including the following databases: MEDLINE, SCOPUS, EBSCO, Science Direct, Cochrane Controlled Trials Register (CENTRAL), WOS, WHO International Clinical Trials Register, Scielo and Google Scholar, considering original studies that evaluated the efficacy of RAD in experimental or clinical contexts from January 1990 to May 2023. Data selection and extraction were performed in triplicate, with a fourth author resolving discrepancies.Results.Twenty articles were included in the review from a total of 373 studies initially selected from the databases. From these, twelve studies were performed under clinical conditions encompassing 3801 fluoroscopically guided procedures, ten studies were performed under experimental conditions with phantoms, with a total of 88 procedures, four studies were performed using numerical calculations with a total of 63 procedures. The attenuation and effectiveness of provided by the caps analyzed in the present review varying from 12.3% to 99.9%, and 4.9% to 91% respectively.Conclusion.RAD were found to potentially provide radiation protection, but a high heterogeneity in the shielding afforded was found. This indicates the need for local assessment of cap efficiency according to the practice.
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  • 文章类型: Journal Article
    目的:本范围综述提供了有关高剂量放射治疗(RT)对骨结构和功能影响的临床前和临床数据。
    方法:对相关问题进行了广泛的PubMed搜索。然后将数据合成为可用的相关体外综合总结,临床前和临床文献。
    结果:高剂量RT对细胞培养物的体外研究表明,骨骼原代细胞的活力和功能能力受到相当大的损害;破骨细胞,成骨细胞,和骨细胞。体内动物模型表明,高剂量RT诱导骨的显著形态变化,抑制骨骼修复损伤的能力,增加骨头的脆性.临床数据表明,随着时间的推移,骨骼受损的风险越来越大,比如骨折,高剂量RT后。
    结论:这些研究结果表明,单部分RT的安全剂量可能存在限制,必须考虑高剂量RT对患者的长期后果。
    OBJECTIVE: This scoping review presents the preclinical and clinical data on the effects of high-dose radiation therapy (RT) on bone structure and function.
    METHODS: An extensive PubMed search was performed for the relevant questions. The data were then synthesized into a comprehensive summary of the available relevant in-vitro, preclinical and clinical literature.
    RESULTS: In-vitro studies of high-dose RT on cell cultures show considerable damage in the viability and functional capacity of the primary cells of the bones; the osteoclasts, the osteoblasts, and the osteocytes. In-vivo animal models show that high-dose RT induces significant morphological changes to the bone, inhibits the ability of bone to repair damage, and increases the fragility of the bone. Clinical data show that there is an increasing risk over time of damage to the bone, such as fractures, after high-dose RT.
    CONCLUSIONS: These findings suggest that there may be a limit to the safe dose for single-fraction RT, and the long-term consequences of high-dose RT for the patients must be considered.
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  • 文章类型: Journal Article
    这项研究澄清了2011年3月11日福岛第一核电站事故中寻求避免辐射暴露的幼儿母亲自我疏散的负面影响。我们对27位母亲进行了半结构化访谈,采用基于面试指南的开放式查询。我们使用Ka-Wakita-Jiro(KJ)方法对其响应进行分析,将结果分为八个不同的组,包括142个标签。这些类别包括对辐射对健康影响的持续焦虑,风险感知的差异,夫妻关系的变化,无法交朋友和寻求支持,作为单亲父母生活,财务问题,他们撤离的区域的陌生感觉,和对未来的不确定性。尽管他们的艰辛,母亲们继续自我疏散以避免放射性。我们的发现强调,即使在自我撤离后,他们对辐射暴露的焦虑仍然存在,导致与可能参与抚养子女的关键人物的关系恶化。这些结果为核事故的间接受害者所经历的挑战提供了宝贵的见解,比如小孩子的母亲。
    This study clarified the negative aspects of the self-imposed evacuation of mothers of small children seeking to avoid radiation exposure from the Fukushima Daiichi Nuclear Power Station accident on 11 March 2011. We conducted semi-structured interviews with 27 mothers, employing open-ended inquiries based on an interview guide. Our analysis of their responses using the Ka-Wakita-Jiro (KJ) method categorized the results into eight distinct groups comprising 142 labels. These categories included continued anxiety about the health effects of radiation, differences in risk perception, changes in spousal relationships, the inability to make friends and find support, living as a single parent, financial concerns, the unfamiliar feel of the area to which they evacuated, and uncertainty about the future. Despite their hardships, the mothers continued their self-imposed evacuation to avoid radioactivity. Our findings underscore that their anxieties about radiation exposure persisted even after self-imposed evacuation, leading to deteriorated relationships with key individuals who would have been involved in raising their children. These results offer valuable insights into the challenges experienced by the indirect victims of the nuclear accident, such as the mothers of small children.
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  • 文章类型: Journal Article
    质子束治疗被认为是相对于电磁辐射向前迈出的一步,由于剂量的减少。在对健康组织的有害影响中,心血管并发症是已知的长期放疗并发症。在质子照射后3天和10天获得的来自异种移植的BALB/c裸小鼠的心脏组织的转录反应被分析为剂量和时间的函数。使用了三种剂量:2Gy,6Gy,9Gy中等剂量在照射后3天造成了最大的影响:在2Gy,219个基因表达不同,其中许多以锌指蛋白为代表;在6Gy时,有1109个,主要涉及能量代谢和对刺激的反应的基因;在9Gy时,共有105个,主要表现为锌指蛋白和参与心脏功能调节的分子。10天后,没有检测到显著的影响,这表明细胞修复机制消除了基因表达的潜在改变。非线性剂量反应曲线表明需要更新建立在光子上的模型,以提高健康风险预测的准确性。我们的数据还表明锌指蛋白基因可能作为质子治疗功效的标志物。
    Proton beam therapy is considered a step forward with respect to electromagnetic radiation, thanks to the reduction in the dose delivered. Among unwanted effects to healthy tissue, cardiovascular complications are a known long-term radiotherapy complication. The transcriptional response of cardiac tissue from xenografted BALB/c nude mice obtained at 3 and 10 days after proton irradiation covering both the tumor region and the underlying healthy tissue was analyzed as a function of dose and time. Three doses were used: 2 Gy, 6 Gy, and 9 Gy. The intermediate dose had caused the greatest impact at 3 days after irradiation: at 2 Gy, 219 genes were differently expressed, many of them represented by zinc finger proteins; at 6 Gy, there were 1109, with a predominance of genes involved in energy metabolism and responses to stimuli; and at 9 Gy, there were 105, mainly represented by zinc finger proteins and molecules involved in the regulation of cardiac function. After 10 days, no significant effects were detected, suggesting that cellular repair mechanisms had defused the potential alterations in gene expression. The nonlinear dose-response curve indicates a need to update the models built on photons to improve accuracy in health risk prediction. Our data also suggest a possible role for zinc finger protein genes as markers of proton therapy efficacy.
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  • 文章类型: Journal Article
    Lynch综合征患者由于DNA错配修复(MMR)基因缺乏而具有遗传的癌症倾向,如果暴露于电离辐射,可能会导致更高的癌症风险。这项初步研究旨在揭示CT相关低剂量(20mGy)和较高治疗剂量(2Gy)下MMR缺乏与放射敏感性之间的关联。
    使用细胞和细胞遗传学分析,在暴露于辐射之前和之后,分析了具有(dMMR)或没有MMR缺陷(pMMR)的人类结直肠癌细胞系。克隆形成测定以确定细胞生殖死亡;姐妹染色单体交换(SCE)测定以检测姐妹染色单体之间的DNA交换;γH2AX测定以分析DNA损伤修复;和凋亡分析以比较细胞死亡反应。在体外评估了这些测定的优点和局限性,并对其适用性和可行性进行了研究,以了解其用于进一步研究的潜力。
    克隆测定的结果表明,在2GyX辐射后,pMMR细胞系(HT29)比dMMR细胞系(HCT116,SW48和LoVo)显着更具放射抗性。细胞类型和辐射剂量都对SCE/染色体的产量有显著影响。当辐射样品的SCE/染色体的产量(2Gy)相对于对照进行归一化时,细胞系之间没有观察到显著差异。对于γH2AX测定,在暴露后30分钟(min)的时间点检查0、20mGy和2Gy,4和24h(h)。统计分析显示,HT29仅比MLH1缺陷细胞系显着更具放射抗性,但不是缺乏MSH2的细胞系。细胞凋亡分析(4Gy)显示HT29比HCT116明显更具放射抗性,尽管观察到非常少的凋亡细胞。
    总的来说,这项研究表明,在一些测定中,MMR熟练细胞系的放射性抗性,但不是在其他人。本研究中使用的所有方法都已得到验证;然而,由于与癌细胞系相关的限制,下一步将是在临床样本中使用这些检测方法,以了解辐射对Lynch患者的生物学和机制影响以及对健康的影响.
    Lynch syndrome patients have an inherited predisposition to cancer due to a deficiency in DNA mismatch repair (MMR) genes which could lead to a higher risk of developing cancer if exposed to ionizing radiation. This pilot study aims to reveal the association between MMR deficiency and radiosensitivity at both a CT relevant low dose (20 mGy) and a therapeutic higher dose (2 Gy).
    Human colorectal cancer cell lines with (dMMR) or without MMR deficiency (pMMR) were analyzed before and after exposure to radiation using cellular and cytogenetic analyses i.e., clonogenic assay to determine cell reproductive death; sister chromatid exchange (SCE) assay to detect the exchange of DNA between sister chromatids; γH2AX assay to analyze DNA damage repair; and apoptosis analysis to compare cell death response. The advantages and limitations of these assays were assessed in vitro, and their applicability and feasibility investigated for their potential to be used for further studies using clinical samples.
    Results from the clonogenic assay indicated that the pMMR cell line (HT29) was significantly more radio-resistant than the dMMR cell lines (HCT116, SW48, and LoVo) after 2 Gy X-irradiation. Both cell type and radiation dose had a significant effect on the yield of SCEs/chromosome. When the yield of SCEs/chromosome for the irradiated samples (2 Gy) was normalized against the controls, no significant difference was observed between the cell lines. For the γH2AX assay, 0, 20 mGy and 2 Gy were examined at post-exposure time points of 30 min (min), 4 and 24 h (h). Statistical analysis revealed that HT29 was only significantly more radio-resistant than the MLH1-deficient cells lines, but not the MSH2-deficient cell line. Apoptosis analysis (4 Gy) revealed that HT29 was significantly more radio-resistant than HCT116 albeit with very few apoptotic cells observed.
    Overall, this study showed radio-resistance of the MMR proficient cell line in some assays, but not in the others. All methods used within this study have been validated; however, due to the limitations associated with cancer cell lines, the next step will be to use these assays in clinical samples in an effort to understand the biological and mechanistic effects of radiation in Lynch patients as well as the health implications.
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  • 文章类型: Journal Article
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  • 文章类型: Journal Article
    随着太赫兹辐射的逐步应用,太赫兹波的生物安全性已成为人们关注的新领域。尽管已经进行了许多研究来研究太赫兹辐射对生物体的影响,太赫兹波的生物学效应尚未完全揭示。在这项研究中,秀丽隐杆线虫(C.线虫)用于评估全身暴露于0.263THz辐照的生物学后果。转录组测序和秀丽隐杆线虫行为测试的整合显示,高功率太赫兹辐射损伤表皮超微结构,抑制角质层胶原基因的表达,并损害了秀丽隐杆线虫的运动。此外,参与免疫系统和神经系统的基因被高功率太赫兹辐射显著下调.我们的发现为高功率THz辐射的生物学影响提供了新的观点,该辐射可能导致表皮损伤并引起系统性反应。
    The biosafety of terahertz (THz) waves has emerged as a new area of concern with the gradual application of terahertz radiation. Even though many studies have been conducted to investigate the influence of THz radiation on living organisms, the biological effects of terahertz waves have not yet been fully revealed. In this study, Caenorhabditis elegans (C. elegans) was used to evaluate the biological consequences of whole-body exposure to 0.263 THz irradiation. The integration of transcriptome sequencing and behavioral tests of C. elegans revealed that high-power THz irradiation damaged the epidermal ultrastructures, inhibited the expression of the cuticle collagen genes, and impaired the movement of C. elegans. Moreover, the genes involved in the immune system and the neural system were dramatically down-regulated by high-power THz irradiation. Our findings offer fresh perspectives on the biological impacts of high-power THz radiation that could cause epidermal damage and provoke a systemic response.
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