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Analysis of the Effect of High-Dose Segmental Citrate Anticoagulation in High Flux Hemodialysis
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作者 Xubo Fu 《Journal of Clinical and Nursing Research》 2024年第5期95-99,共5页
Objective:To analyze the clinical effect of high-dose citrate in segmental extracorporeal anticoagulation for high-throughput hemodialysis.Methods:The subjects included in this study were admitted to the hospital for ... Objective:To analyze the clinical effect of high-dose citrate in segmental extracorporeal anticoagulation for high-throughput hemodialysis.Methods:The subjects included in this study were admitted to the hospital for maintenance hemodialysis treatment from January 2021 to January 2023.All patients had a high risk of bleeding and received 4%trisodium citrate anticoagulant treatment,administered at a rate of 200 mL/h before and after the dialyzer.The anticoagulant effects achieved by the patients were observed and analyzed.Results:The total number of patients who received high-dose segmented citrate extracorporeal anticoagulation dialysis treatment was 50,with each patient undergoing 100 treatments.During the treatment,2 patients had to end the treatment early due to transmembrane pressure exceeding 30 mmHg and an increase in venous pressure exceeding 250 mmHg;the treatment times for these patients were 20 minutes and 200 minutes,respectively.The remaining patients successfully completed the 4-hour treatment.Blood pH and calcium ion concentration in the venous pot were monitored.It was observed that before dialysis,after 2 hours of dialysis,and at the end of dialysis,the blood pH of the patients remained within a relatively normal range.Although some patient levels changed after dialysis,they remained within the normal range.No adverse reactions(such as numbness of the limbs or convulsions)were observed during the anticoagulant treatment.Conclusion:Administering 4%trisodium citrate at a rate of 200 mL/h before and after the dialyzer achieves a good anticoagulant effect,maintains the patient’s blood gas levels within the normal range at the end of dialysis,and causes no adverse reactions. 展开更多
关键词 High dose Segmented citrate High flux HEMODIALYSIS Anticoagulation effect
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Systematic analysis and modeling of the FLASH sparing effect as a function of dose and dose rate
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作者 Qi-Bin Fu Yan Zhang +3 位作者 Yu-Cheng Wang Tu-Chen Huang Hong-Yu Zhu Xiao-Wu Deng 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2024年第10期51-58,共8页
Ultrahigh-dose-rate radiotherapy(FLASH-RT)is a revolutionary radiotherapy technology that can spare normal tissues without compromising tumor control.Although qualitative experimental results have been reported,quanti... Ultrahigh-dose-rate radiotherapy(FLASH-RT)is a revolutionary radiotherapy technology that can spare normal tissues without compromising tumor control.Although qualitative experimental results have been reported,quantitative and systematic analysis of data is necessary.Particularly,the FLASH effect response model to the dose or dose rate is still unclear.This study investigated the relationships between the FLASH effect and experimental parameters,such as dose,dose rate,and other factors by analyzing published in vivo experimental data from animal models.The data were modeled based on logistic regression analysis using the sigmoid function.The model was evaluated using prediction accuracy,receiver operating characteristic(ROC)curve,and area under the ROC curve.Results showed that the FLASH effect was closely related to the dose,mean dose rate,tissue type,and corresponding biological endpoints.The dose rate corresponding to a 50% probability of triggering cognitive protection in the brain was 45 Gy s^(-1).The dose rate corresponding to a 50% probability of triggering intestinal crypt survival and regeneration was 140 Gy s^(-1).For the skin toxicity effect,the dose corresponding to a 50% probability of triggering the FLASH effect was 24 Gy.This study helps to characterize the conditions underlying the FLASH effect and provides important information for optimizing experiments. 展开更多
关键词 FLASH radiotherapy Sparing effect Systematic analysis dose rate dose Biological endpoints
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Novel miR-490-3p/hnRNPA1-b/PKM2 axis mediates the Warburg effect and proliferation of colon cancer cells via the PI3K/AKT pathway
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作者 Xiang-Hui Wan Guo-Bing Jin +8 位作者 Qun Yang Ji-Long Hu Zhi-Liang Liu Jun Rao Can Wen Peng-Ling Li Xi-Mei Yang Bo Huang Xiao-Zhong Wang 《World Journal of Gastrointestinal Oncology》 SCIE 2024年第5期2038-2059,共22页
BACKGROUND Heterogeneous ribonucleoprotein A1(hnRNPA1)has been reported to enhance the Warburg effect and promote colon cancer(CC)cell proliferation,but the role and mechanism of the miR-490-3p/hnRNPA1-b/PKM2 axis in ... BACKGROUND Heterogeneous ribonucleoprotein A1(hnRNPA1)has been reported to enhance the Warburg effect and promote colon cancer(CC)cell proliferation,but the role and mechanism of the miR-490-3p/hnRNPA1-b/PKM2 axis in CC have not yet been elucidated.AIM To investigate the role and mechanism of a novel miR-490-3p/hnRNPA1-b/PKM2 axis in enhancing the Warburg effect and promoting CC cell proliferation through the PI3K/AKT pathway.METHODS Paraffin-embedded pathological sections from 220 CC patients were collected and subjected to immunohistochemical analysis to determine the expression of hnRNPA1-b.The relationship between the expression values and the clinicopathological features of the patients was investigated.Differences in mRNA expression were analyzed using quantitative real-time polymerase chain reaction,while differences in protein expression were analyzed using western blot.Cell proliferation was evaluated using the cell counting kit-8 and 5-ethynyl-2’-deoxyuridine assays,and cell cycle and apoptosis were detected using flow cytometric assays.The targeted binding of miR-490-3p to hnRNPA1-b was validated using a dual luciferase reporter assay.The Warburg effect was evaluated by glucose uptake and lactic acid production assays.RESULTS The expression of hnRNPA1-b was significantly increased in CC tissues and cells compared to normal controls(P<0.05).Immunohistochemical results demonstrated significant variations in the expression of the hnRNPA1-b antigen in different stages of CC,including stage I,II-III,and IV.Furthermore,the clinicopathologic characterization revealed a significant correlation between hnRNPA1-b expression and clinical stage as well as T classification.HnRNPA1-b was found to enhance the Warburg effect through the PI3K/AKT pathway,thereby promoting proliferation of HCT116 and SW620 cells.However,the proliferation of HCT116 and SW620 cells was inhibited when miR-490-3p targeted and bound to hnRNPA1-b,effectively blocking the Warburg effect.CONCLUSION These findings suggest that the novel miR-490-3p/hnRNPA1-b/PKM2 axis could provide a new strategy for the diagnosis and treatment of CC. 展开更多
关键词 Heterogeneous ribonucleoprotein A1-b MiR-490-3p Colon cancer Alternative splicing Warburg effect
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Laser-assisted Simulation of Dose Rate Effects of Wide Band Gap Semiconductor Devices
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作者 TANG Ge XIAO Yao +3 位作者 SUN Peng LIU Jingrui ZHANG Fuwang LI Mo 《原子能科学技术》 EI CAS CSCD 北大核心 2023年第12期2314-2325,共12页
Laser-assisted simulation technique has played a crucial role in the investigation of dose rate effects of silicon-based devices and integrated circuits,due to its exceptional advantages in terms of flexibility,safety... Laser-assisted simulation technique has played a crucial role in the investigation of dose rate effects of silicon-based devices and integrated circuits,due to its exceptional advantages in terms of flexibility,safety,convenience,and precision.In recent years,wide band gap materials,known for their strong bonding and high ionization energy,have gained increasing attention from researchers and hold significant promise for extensive applications in specialized environments.Consequently,there is a growing need for comprehensive research on the dose rate effects of wide band gap materials.In response to this need,the use of laser-assisted simulation technology has emerged as a promising approach,offering an effective means to assess the efficacy of investigating these materials and devices.This paper focused on investigating the feasibility of laser-assisted simulation to study the dose rate effects of wide band gap semiconductor devices.Theoretical conversion factors for laser-assisted simulation of dose rate effects of GaN-based and SiC-based devices were been provided.Moreover,to validate the accuracy of the conversion factors,pulsed laser and dose rate experiments were conducted on GaN-based and SiC-based PIN diodes.The results demonstrate that pulsed laser radiation andγ-ray radiation can produce highly similar photocurrent responses in GaN-based and SiC-based PIN diodes,with correlation coefficients of 0.98 and 0.974,respectively.This finding reaffirms the effectiveness of laser-assisted simulation technology,making it a valuable complement in studying the dose rate effects of wide band gap semiconductor devices. 展开更多
关键词 laser-assisted simulation dose rate effect wide band gap semiconductor conversion factor
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Synergistic effect of total ionizing dose on single-event gate rupture in SiC power MOSFETs
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作者 曹荣幸 汪柯佳 +9 位作者 孟洋 李林欢 赵琳 韩丹 刘洋 郑澍 李红霞 蒋煜琪 曾祥华 薛玉雄 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第6期666-672,共7页
The synergistic effect of total ionizing dose(TID) and single event gate rupture(SEGR) in SiC power metal–oxide–semiconductor field effect transistors(MOSFETs) is investigated via simulation. The device is found to ... The synergistic effect of total ionizing dose(TID) and single event gate rupture(SEGR) in SiC power metal–oxide–semiconductor field effect transistors(MOSFETs) is investigated via simulation. The device is found to be more sensitive to SEGR with TID increasing, especially at higher temperature. The microscopic mechanism is revealed to be the increased trapped charges induced by TID and subsequent enhancement of electric field intensity inside the oxide layer. 展开更多
关键词 SiC power MOSFET total ionizing dose(TID) single event gate rupture(SEGR) synergistic effect TCAD simulation
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Effectiveness of COVID-19 Vaccine Doses in Children: Case of Lake Region Economic Bloc-Kenya
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作者 Shem Otoi Sam Naomy Onyuka +1 位作者 Michael Audi Khama Rogo 《Open Journal of Modelling and Simulation》 2023年第3期88-97,共10页
Introduction: Vaccination of children has experienced delays due to paucity of information regarding safety, effectiveness, immunogenicity, and reactogenicity. Age wise approval prioritized 12 - 17 years and later 5 -... Introduction: Vaccination of children has experienced delays due to paucity of information regarding safety, effectiveness, immunogenicity, and reactogenicity. Age wise approval prioritized 12 - 17 years and later 5 - 11 years. Those below 5 years possess na?ve immunity and not considered. In Lake Region Economic Bloc children aged 12 - 17 variably received 1, 2, and 3 doses of vaccine. This analysis looks into effectiveness of the doses administered. Method: Data providers from 84 LREB facilities submitted patients’ vaccination data to Power BI supported dashboard between June 24, 2021 and July 30, 2022. Data of 12 - 17 years old was mined, analyzed and visualized. Sample sizes considered for analysis were 0 dose, n = 8132;1 dose, n = 271;2 doses, n = 402, and 3 doses, n = 90. Data used in the analysis was facility operational and not from experimental design. Relative risk analysis of children who received 0, 1, 2, and 3 doses was done using Odds Ratio run on R software. Results: The relative risk of infection to a child with one dose against unvaccinated counterpart is 0.92 (95% CI, 0.61 - 1.43). Likewise the relative risk of infection to a child aged 12 - 17 years with 2 doses against another who received no dose is 0.87 (95% CI, 0.63 - 1.24). A child with 3 doses is 46% (95% CI, 27% - 84%) less likely to get infected compared to another not vaccinated. Also, the relative risk between having 2 doses and 1 dose for a child aged 12 - 17 years is 0.95 (95% CI, 0.55 - 1.6). For the same age group the relative risk of having 3 doses of vaccines against 1 dose is 51% (95% CI, 26% - 100%). In addition, a child who receives 3 doses of vaccine is 53% (95% CI, 28% - 100%) less likely to experience breakthrough infection compared to another with 2 doses. Whereas 1<sup>st</sup> dose offers (5%) marginal protection advantage over the 2<sup>nd</sup> dose, the 3r dose offers 49% and 47% more protection over 1<sup>st</sup> and 2<sup>nd</sup> doses, respectively, because of incremental reduced risk of infection gained from previous doses. During the period, 15 children at risk were admitted with COVID-19 infections in various regional hospitals, one had 3 doses but confounded with severe comorbidity. Conclusion: We found that 2<sup>nd</sup> dose had marginal protection over the 1<sup>st</sup> dose. However, the 3<sup>rd</sup> dose offers extensive protection compared to 1<sup>st</sup> and 2<sup>nd</sup> doses, and protects more against hospitalization. Children at risk should receive 3 doses of vaccines. 展开更多
关键词 Children Vaccination doses effectIVENESS
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药动学-药效学结合模型在中医药领域中的应用与展望 被引量:1
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作者 惠梦雨 刘平 张华 《上海中医药杂志》 CSCD 2024年第2期40-45,共6页
药动学-药效学(PK-PD)结合模型研究目的在于确定药物浓度与效应以及药物在体内的动态变化对药效强度及持续时间的影响。不同于化学药物有明确的成分与作用机制,中药具有多成分、多靶点、多途径、多效应的特点,因此PK-PD结合模型在中医... 药动学-药效学(PK-PD)结合模型研究目的在于确定药物浓度与效应以及药物在体内的动态变化对药效强度及持续时间的影响。不同于化学药物有明确的成分与作用机制,中药具有多成分、多靶点、多途径、多效应的特点,因此PK-PD结合模型在中医药领域中的应用尚不成熟。基于中药PK-PD结合模型研究现状,建立多学科交叉的中医药PK-PD结合模型研究体系及探索建立合适的PK-PD结合模型分析中西药联合应用的量-时-效间关系,有望为中药研究及其合理应用、开发以及确定剂量、剂型等方面提供参考。 展开更多
关键词 中药 药动学 药效学 PK-PD结合模型 效应成分 量效关系 学科交叉
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儿童青少年执行功能与单次运动剂量-效应关系的meta分析 被引量:1
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作者 宋庆尧 于瀛 +2 位作者 樊晓飞 孙平 王武年 《中国心理卫生杂志》 CSCD 北大核心 2024年第2期122-130,共9页
目的:检验儿童青少年执行功能与单次运动之间的剂量-效应关系。方法:检索中国知网、维普、PubMed、Scopus、Web of Science、EBSCO数据库中关于单次运动对儿童青少年执行功能影响的实验研究,运用Review Manager 5.4软件进行meta分析。结... 目的:检验儿童青少年执行功能与单次运动之间的剂量-效应关系。方法:检索中国知网、维普、PubMed、Scopus、Web of Science、EBSCO数据库中关于单次运动对儿童青少年执行功能影响的实验研究,运用Review Manager 5.4软件进行meta分析。结果:共纳入14篇文献,包含691名被试;单次运动对改善抑制功能反应时[SMD=-0.78 (-1.35,-0.25),P=0.004]和正确率[SMD=0.91(0.27,1.55),P=0.005]、刷新功能反应时[SMD=-1.04 (-2.01,-0.07),P=0.030]和正确率[SMD=1.16 (0.39,1.93),P=0.003]有效果;单次运动以静止运动、30 min、中等强度对改善儿童青少年抑制功能反应时效应量(-5.86、-1.41、-0.76)、抑制功能正确率效应量(2.98、5.64、1.62)和刷新功能正确率效应量(6.27、7.39、2.57)最大(均P<0.05)。结论:单次运动可改善儿童青少年执行功能中的抑制功能和刷新功能。 展开更多
关键词 单次运动 执行功能 剂量-效应 儿童 青少年
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基于X射线晶圆在线辐照实验的16 nm n-FinFETs总剂量效应模型研究
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作者 魏雪雯 郑齐文 +2 位作者 崔江维 李豫东 郭旗 《现代应用物理》 2024年第4期116-123,共8页
建立了基于X射线晶圆在线辐照实验的16 nm FinFET总剂量效应模型,并对模型的有效性进行了验证。将辐照后器件等效为一个主晶体管与辐射导致的若干寄生晶体管并联,通过改变寄生晶体管的参数对辐照中的物理机制进行了模拟。对不同鳍片数... 建立了基于X射线晶圆在线辐照实验的16 nm FinFET总剂量效应模型,并对模型的有效性进行了验证。将辐照后器件等效为一个主晶体管与辐射导致的若干寄生晶体管并联,通过改变寄生晶体管的参数对辐照中的物理机制进行了模拟。对不同鳍片数量的内核(core)和输入输出(input output,IO)n-FinFET建立了能够描述器件在不同漏源电压下工作性能的模型,仿真结果与实验数据对比表明,所建立的模型的相对均方根偏差小于15%。 展开更多
关键词 FINFET 总剂量效应 SPICE模型 辐射损伤 器件可靠性
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基于VHDL-AMS的模数转换器辐射效应建模与仿真方法
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作者 梁博 刘锦辉 +3 位作者 张晓鹏 谭雯丹 张馨丹 刘刚 《电子学报》 EI CAS CSCD 北大核心 2024年第8期2706-2717,共12页
模数转换器(Analog-to-Digital Converter,ADC)是连接模拟信号域与数字信号域的关键器件,而现有研究缺乏ADC辐照效应建模的相关内容.为满足大型模数混合信号系统辐照效应建模仿真的需要,本文提出了建立具有辐照效应的ADC行为级模型的方... 模数转换器(Analog-to-Digital Converter,ADC)是连接模拟信号域与数字信号域的关键器件,而现有研究缺乏ADC辐照效应建模的相关内容.为满足大型模数混合信号系统辐照效应建模仿真的需要,本文提出了建立具有辐照效应的ADC行为级模型的方法.首先根据ADC的工作原理将其拆解为不同的通用模块,使用模拟和混合信号硬件描述语言(Very High speed integrated circuit hardware Description Language for Analog and Mixed Signals,VHDL-AMS)建立了各模块的行为级模型.接着根据基本原理将各模块动态组合为未辐照情况下基本的ADC模型.对于ADC的辐照效应,通过开展辐照试验,测量了ADC芯片HWD7710和SAD9434受总剂量(Total Ionizing Dose,TID)效应和中子辐射(Neutron Radiation,NR)效应影响的工作参数,并利用最小二乘法拟合获得ADC的工作参数与辐照剂量的关系式.最后根据辐照关系式,在基本模型上添加辐照参数模块,并建立两种不同结构ADC的TID与NR模型.通过仿真结果与试验数据对比,验证了所建ADC辐射效应模型的普适性和精度.模型的静态参数仿真结果与试验结果的相对偏差在5%以内,证明该方法支持对不同ADC及不同辐射效应进行辐照效应模型建模. 展开更多
关键词 模数转换器 建模方法 总剂量效应 中子辐射效应 静态参数 动态参数
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Total ionizing dose and synergistic effects of magnetoresistive random-access memory 被引量:9
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作者 Xing-Yao Zhang Qi Guo +1 位作者 Yu-Dong Li Lin Wen 《Nuclear Science and Techniques》 SCIE CAS CSCD 2018年第8期136-140,共5页
A magnetoresistive random-access memory(MRAM) device was irradiated by ^(60) Co c-rays and an electron beam.The synergistic effect of this on the MRAM was tested with an additional magnetic field during irradiation,fr... A magnetoresistive random-access memory(MRAM) device was irradiated by ^(60) Co c-rays and an electron beam.The synergistic effect of this on the MRAM was tested with an additional magnetic field during irradiation,from which the total ionizing dose(TID) and the synergistic damage mechanism of MRAM were analyzed.In addition,DC,AC,and functional parameters of the memory were tested under irradiation and annealing via a very large-scale integrated circuit test system.The radiation-sensitive parameters were obtained through analyzing the data.Because of the magnetic field applied on the MRAM while testing the synergistic effects,shallow trench isolation leakage and Frenkel–Poole emission due to synergistic effects were smaller than that of TID,and hence radiation damage of the synergistic effects was also lower. 展开更多
关键词 随机存取 剂量 电离 记忆 集成电路测试 MRAM TID 存储器
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Effects of total dose irradiation on the threshold voltage of H-gate SOI NMOS devices 被引量:3
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作者 Qian-Qiong Wang Hong-Xia Liu +3 位作者 Shu-Peng Chen Shu-Long Wang Chen-Xi Fei Dong-Dong Zhao 《Nuclear Science and Techniques》 SCIE CAS CSCD 2016年第5期193-199,共7页
This work researched the impact of total dose irradiation on the threshold voltage of N-type metal oxide semiconductor field effect transistors(nMOSFETs) in silicon-on-insulator(SOI) technology.Using the subthreshold ... This work researched the impact of total dose irradiation on the threshold voltage of N-type metal oxide semiconductor field effect transistors(nMOSFETs) in silicon-on-insulator(SOI) technology.Using the subthreshold separation technology,the factor causing the threshold voltage shift was divided into two parts:trapped oxide charges and interface states,the effects of which are presented under irradiation.Furthermore,by analyzing the data,the threshold voltage shows a negative shift at first and then turns to positive shift when irradiation dose is lower.Additionally,the influence of the dose rate effects on threshold voltage is discussed.The research results show that the threshold voltage shift is more significant in low dose rate conditions,even for a low dose of100 krad(Si).The degeneration value of threshold voltage is 23.4%and 58.0%for the front-gate and the back-gate at the low dose rate,respectively. 展开更多
关键词 阈值电压漂移 总剂量辐照 NMOS器件 SOI 金属氧化物半导体场效应晶体管 H型 低剂量率 分离技术
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老年人体力活动与身体成分、骨密度的剂量-效应关系研究 被引量:1
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作者 金家辉 李星燕 +1 位作者 王佳晶 苏美华 《体育研究与教育》 2024年第3期84-89,共6页
目的:通过分析老年人的体力活动水平与身体成分、骨密度的剂量-效应关系,为老年人采用合理的运动剂量干预骨质疏松症提供数据参考。方法:随机分层选取厦门市集美区的60岁以上老年人129名,采用国际体力活动问卷调查其体力活动水平,并测... 目的:通过分析老年人的体力活动水平与身体成分、骨密度的剂量-效应关系,为老年人采用合理的运动剂量干预骨质疏松症提供数据参考。方法:随机分层选取厦门市集美区的60岁以上老年人129名,采用国际体力活动问卷调查其体力活动水平,并测定其身体形态、超声骨密度和身体成分。结果:(1)低水平组体脂率、腰臀比明显高于中、高水平组;其肌肉含量较中高体力活动组明显降低。(2)低水平组骨质疏松发生率明显高于中、高水平组。(3)体力活动量与跟骨骨密度(BMD)、骨强度指数存在显著正相关性;而年龄与跟骨BMD、骨强度指数存在负相关性。(4)体力活动量与肌肉量存在正相关性,而与体脂率呈现负相关性;年龄与肌肉量呈现负相关性,而与体脂率呈现正相关性。结论:老年人群体力活动水平与骨质健康存在剂量-效应关系。 展开更多
关键词 老年人 体力活动 骨密度 剂量效应
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Machine learning-based analyses for total ionizing dose effects in bipolar junction transistors 被引量:5
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作者 Bai-Chuan Wang Meng-Tong Qiu +2 位作者 Wei Chen Chen-Hui Wang Chuan-Xiang Tang 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2022年第10期106-116,共11页
Machine learning methods have proven to be powerful in various research fields.In this paper,we show that research on radiation effects could benefit from such methods and present a machine learning-based scientific d... Machine learning methods have proven to be powerful in various research fields.In this paper,we show that research on radiation effects could benefit from such methods and present a machine learning-based scientific discovery approach.The total ionizing dose(TID)effects usually cause gain degradation of bipolar junction transistors(BJTs),leading to functional failures of bipolar integrated circuits.Currently,many experiments of TID effects on BJTs have been conducted at different laboratories worldwide,producing a large amount of experimental data which provides a wealth of information.However,it is difficult to utilize these data effectively.In this study,we proposed a new artificial neural network(ANN)approach to analyze the experimental data of TID effects on BJTs An ANN model was built and trained using data collected from different experiments.The results indicate that the proposed ANN model has advantages in capturing nonlinear correlations and predicting the data.The trained ANN model suggests that the TID hardness of a BJT tends to increase with base current I.A possible cause for this finding was analyzed and confirmed through irradiation experiments. 展开更多
关键词 Total ionizing dose effects Bipolar junction transistor Artificial neural network Machine learning Radiation effects
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Public Effective Dose Assessment Using Gross Alpha and Beta Radioactivity Levels of Tap Drinking Water in the District of Abidjan, Cote d’Ivoire
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作者 Ponaho Claude Kezo Issa Konate Tekpo Paul Dali 《Journal of Environmental Protection》 CAS 2023年第3期127-138,共12页
In order to assess public effective dose due to gross alpha and beta in water, 43 tap water samples were collected from different areas in the District of Abidjan. Using the low background Gas-less Automatic Alpha/Bet... In order to assess public effective dose due to gross alpha and beta in water, 43 tap water samples were collected from different areas in the District of Abidjan. Using the low background Gas-less Automatic Alpha/Beta counting system (Canberra iMatic<sup>TM</sup>) for analysis, the gross alpha and beta concentrations found varied from 0.001 ± 0.002 to 0.063 ± 0.050 Bq/l with an average of 0.013 ± 0.012 Bq/l and from 0.067 ± 0.080 to 0.320 ± 0.120 Bq/l with an average of 0.174 ± 0.076 Bq/l, respectively in samples. The public effective dose assessment showed values of dose to ingestion of alpha and beta emitter radionuclides lower than the recommended value of dose for drinking water 0.1 mSv/y, except in 30% of the samples. These results show the need for additional studies to be conducted in order to clarify the hazardousness of these water samples. However, this study still remains important because it has provided necessary data for future tap water quality monitoring studies in the District of Abidjan. 展开更多
关键词 Gross Alpha and Beta Concentration Tap Water effective dose District of Abidjan
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Synergistic effects of total ionizing dose and radiated electromagnetic interference on analog-to-digital converter 被引量:3
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作者 Ping Wu Lin Wen +3 位作者 Zhi-Qian Xu Yun-Sheng Jiang Qi Guo Cui Meng 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2022年第3期172-180,共9页
The influence of combined total ionization dose(TID)and radiated electromagnetic interference(EMI)in a commercial analog-to-digital converter(ADC)was studied.The degradation of the direct-current response,the static p... The influence of combined total ionization dose(TID)and radiated electromagnetic interference(EMI)in a commercial analog-to-digital converter(ADC)was studied.The degradation of the direct-current response,the static parameters,and the dynamic parameters caused by the TID and EMI separately and synergistically is presented.The experimental results demonstrate that the increase in TID intensifies data error and the signal-tonoise ratio(SNR)degradation caused by radiated EMI.The cumulative distribution function of EMI failure with respect to data error and SNR with different TIDs was extracted.The decreasing trend of the threshold was acquired with a small sample size of five for each TID group.The result indicates that the ADC is more sensitive in a compound radiation environment. 展开更多
关键词 Integrated circuit Total ionizing dose Electromagnetic radiation Synergistic effect Combined environment
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Dose-effect correlation of chloride de-icing salt on Euonymus japonicus 被引量:1
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作者 Zhou-Yuan LI Jun-Hui ZHOU Ying-Mei LIANG 《Forestry Studies in China》 CAS 2013年第3期238-245,共8页
In order to prevent severe pollution by de-icing salt on greenery along urban roads, a half lethal dose (LD_50)for a plant population was confirmed through stress simulation of chloride de-icing salt on Euonymus jap... In order to prevent severe pollution by de-icing salt on greenery along urban roads, a half lethal dose (LD_50)for a plant population was confirmed through stress simulation of chloride de-icing salt on Euonymus japonicus, with an ianalysis of physiological changes, statistics on mortality rate on plant populations and mathematic modeling during a 30- day subacute toxicity test. The results indicate that a significant positive correlation in the early stages and a significant negative correlation in the later stages were observed between the amount of chlorophyll a and b in plants and a cumulative dose of de-icing salt. The amounts of free proline in plants and the dose of de-icing salt were positively correlated Over the entire period. No significant correlation in the initial stage, but a significant negative correlation in later stages was observed between the soluble protein and the dose of de-icing salt. LDs0 of this chloride agent on E. japonicus is 5 kg.(L·m2)-1 over 30 days. 展开更多
关键词 de-icing salt Euonymus japonicus dose-effect correlation half lethal dose
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Measurement of Electron Return Effect and Skin Dose Reduction by a Bolus in an Anthropomorphic Physical Phantom under a Magnetic Resonance Guided Linear Accelerator (MR-LINAC) System 被引量:1
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作者 Eun Young Han Zhifei Wen +2 位作者 Hannah J. Lee Arnold dela Cruz Paulino Choonsik Lee 《International Journal of Medical Physics, Clinical Engineering and Radiation Oncology》 2018年第3期339-346,共8页
Background: Magnetic resonance image-guided radiation therapy (MR-IGRT) promises more precise and effective radiation treatments compared to conventional IGRT by using real-time on-board MR imaging. Under the influenc... Background: Magnetic resonance image-guided radiation therapy (MR-IGRT) promises more precise and effective radiation treatments compared to conventional IGRT by using real-time on-board MR imaging. Under the influence of a magnetic field, however, secondary electrons exiting a surface can be forced in a circular path and re-enter the medium, resulting in dose increase at a beam-exit surface, called the electron return effect (ERE). The purpose of the study is to compare the exit skin dose computed by Monte Carlo dose calculation with measurements using an adult anthropomorphic phantom and to measure the effect of skin dose reduction by adding 1 cm-thick bolus. Method: The plan was compared with measurements using an adult anthropomorphic phantom combined with radiochromic films and thermoluminescent dosimeters. We also measured the skin dose reduction by adding 1 cm-thick bolus on the frontal surface of the phantom. Results: We found that 1 cm-thick bolus reduced the skin dose by up to 20% both in measurements and calculations. The plan was found to overestimate the measured skin dose by about 10% and there was no significant difference in the bolus effect between the breast skin and the skin (without breast attachment) doses. Conclusion: In conclusion, we confirmed the ERE effect on the anthropomorphic phantom under the magnetic field and the exit skin dose reduction by adding a bolus. Skin dose measurements using anthropomorphic phantom may be helpful to evaluate more realistic skin dose and the bolus effect in the magnetic field. 展开更多
关键词 MR-Linac ELECTRON RETURN effect Skin dose
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Dose-dependent effects of NMDA on retinal and optic nerve morphology in rats 被引量:1
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作者 Lidawani Lambuk Azliana Jusnida Ahmad Jafri +5 位作者 Igor Iezhitsa Renu Agarwal Nor Salmah Bakar Puneet Agarwal Aimy Abdullah Nafeeza Mohd Ismail 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2019年第5期746-753,共8页
AIM: To investigate dose-dependent effects of N-methylD-aspartate(NMDA) on retinal and optic nerve morphology in rats.METHODS: Sprague Dawley rats, 180-250 g in weight were divided into four groups. Groups 1, 2, 3 and... AIM: To investigate dose-dependent effects of N-methylD-aspartate(NMDA) on retinal and optic nerve morphology in rats.METHODS: Sprague Dawley rats, 180-250 g in weight were divided into four groups. Groups 1, 2, 3 and 4 were intravitreally administered with vehicle and NMDA at the doses 80, 160 and 320 nmol respectively. Seven days after injection, rats were euthanized, and their eyes were taken for optic nerve toluidine blue and retinal hematoxylin and eosin stainings. The TUNEL assay was done for detecting apoptotic cells.RESULTS: All groups treated with NMDA showed significantly reduced ganglion cell layer(GCL) thickness within inner retina, as compared to control group. Group NMDA 160 nmol showed a significantly greater GCL thickness than the group NMDA 320 nmol. Administration of NMDA also resulted in a dose-dependent decrease in the number of nuclei both per 100 μm GCL length and per 100 μm2 of GCL. Intravitreal NMDA injection caused dosedependent damage to the optic nerve. The degeneration of nerve fibres with increased clearing of cytoplasm was observed more prominently as the NMDA dose increased. In accordance with the results of retinal morphometry analysis and optic nerve grading, TUNEL staining demonstrated NMDA-induced excitotoxic retinal injury in a dose-dependent manner.CONCLUSION: Our results demonstrate dose-dependent effects of NMDA on retinal and optic nerve morphology in rats that may be attributed to differences in the severity of excitotoxicity and oxidative stress. Our results also suggest that care should be taken while making dose selections experimentally so that the choice might best uphold study objectives. 展开更多
关键词 GLAUCOMA EXCITOTOXICITY N-methyl-Daspartate retina optic nerve dose-DEPENDENT effectS
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Toxic Effects of Tetrabromobisphenol A on Thyroid Hormones in SD Rats and the Derived-reference Dose 被引量:3
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作者 YANG Yan NI Wei Wei +2 位作者 YU Lin CAI Ze YU Yun Jiang 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2016年第4期295-299,共5页
The present study determined the thyroid hormone interference of tetrabromobisphenol A (TBBPA) in Sprague-Dawley (SD) rats, and the derived-reference dose (RfD) of different endpoint effects on mammals based on ... The present study determined the thyroid hormone interference of tetrabromobisphenol A (TBBPA) in Sprague-Dawley (SD) rats, and the derived-reference dose (RfD) of different endpoint effects on mammals based on experimental results and data collection. Based on repeated exposure toxicity tests on mammals and extensive research, the present study used BMDS240 Software to derive a benchmark dose, and analyzed the accuracy and uncertainty, and similarity with other studies. Test results on triiodothyronine (T3), thyroxine (T4), and thyroid stimulating hormone (TSH) demonstrated that all the indicators presented a non-monotonous dose-effect relationship clearly, except TSH in male rats exposed to 0-1000 mg/kg BW per day. Therefore, RfDs were derived from different critical effects. In summary, RfD for mammals in the present study was found to be 0.6 mg/kg per day. 展开更多
关键词 TBBPA Toxic effects of Tetrabromobisphenol A on Thyroid Hormones in SD Rats and the Derived-reference dose SD
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