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Waning of Anti-Spike IgG Antibody Titer after COVID-19 Vaccination: Myth or Reality?
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作者 Laurent Dupoirieux 《Journal of Biosciences and Medicines》 2023年第8期44-50,共7页
This observational prospective study was conducted on 25 patients who had received a full 3-dose COVID-19 vaccination scheme with a follow-up ranging from 12 to 19 months after the last injection. The aim of the study... This observational prospective study was conducted on 25 patients who had received a full 3-dose COVID-19 vaccination scheme with a follow-up ranging from 12 to 19 months after the last injection. The aim of the study was focused on a single biological indicator the anti-spike IgG antibody titer. The age of the patients ranged from 51 to 85 years old. 15 out 25 patients (60%) presented a comorbidity. Our data showed a persistent positive anti-spike IgG antibodies titer ranging from 105 to 5680 BAU/mL (mean: 2661 BAU/mL) in all patients. In view of these results, systematic administration of a SARS-CoV-2 vaccine booster is questionable and should be individually tailored according to the patient medical condition and the anti-spike IgG antibody level. 展开更多
关键词 SARS-CoV-2 COVID-19 Vaccines anti-spike IgG antibodies
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Spiking neural P systems with anti-spikes and without annihilating priority as number acceptors
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作者 Gangjun Tan Tao Song Zhihua Chen 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2014年第3期464-469,共6页
Spiking neural P systems with anti-spikes (ASN P systems) are variant forms of spiking neural P systems, which are inspired by inhibitory impulses/spikes or inhibitory synapses. The typical feature of ASN P systems ... Spiking neural P systems with anti-spikes (ASN P systems) are variant forms of spiking neural P systems, which are inspired by inhibitory impulses/spikes or inhibitory synapses. The typical feature of ASN P systems is when a neuron contains both spikes and anti-spikes, spikes and anti-spikes wil immediately annihilate each other in a maximal way. In this paper, a restricted variant of ASN P systems, cal ed ASN P systems without anni-hilating priority, is considered, where the annihilating rule is used as the standard rule, i.e., it is not obligatory to use in the neuron associated with both spikes and anti-spikes. If the annihilating rule is used in a neuron, the annihilation wil consume one time unit. As a result, such systems using two categories of spiking rules (identified by (a, a) and (a,a^-)) can achieve Turing completeness as number accepting devices. 展开更多
关键词 membrane computing spiking neural P system Turing completeness register machine anti-spike.
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Predictors of anti-SARS-CoV-2 seropositivity:An Egyptian population-based study
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作者 Engy Mohamed El-Ghitany Ayat Ashour +2 位作者 Azza Galal Farghaly Mona H.Hashish Eman A.Omran 《Infectious Medicine》 2022年第2期113-123,共11页
Background:Population-based studies on the determinants of COVID-19 seroprevalence constitute a cornerstone in guiding appropriate preventive measures.Such studies are scarce in Egypt,thus we conducted this study to e... Background:Population-based studies on the determinants of COVID-19 seroprevalence constitute a cornerstone in guiding appropriate preventive measures.Such studies are scarce in Egypt,thus we conducted this study to explore risk factors for SARS-CoV-2 seropositivity.Methods:This survey included 2919 participants from 10 Egyptian governorates.Sera were tested for SARS-CoV-2 spike(S)and nucleocapsid(N)antibodies.Univariate and multivariate analyses were performed to identify associated factors and predictors of seropositivity regarding sociodemographic factors,clinical data,and personal practices of participants.A subgroup analysis was performed to investigate the occupational risks of seropositivity.Results:Seropositivity was recorded in 1564 participants(53.6%).Independent predictors of seropositivity in-cluded non-smokers(aOR=1.817;95%CI:1.407-2.346,p=0.000),having blood group A(aOR=1.231;95%CI:1.016-1.493,p=0.034),a history of COVID-19 infection(aOR=2.997;95%CI:2.176-4.127,p=0.000),COVID-19 vaccination(aOR=4.349;95%CI:2.798-6.759,p=0.000),higher crowding index(aOR=1.229;95%CI:1.041-1.451,p=0.015),anosmia and/or ageusia(aOR=3.453;95%CI:2.661-4.481,p=0.000)and history of fever(aOR=1.269;95%CI:1.033-1.560,p=0.023).Healthcare worker and Obesity/overweight were additional significant predictors of seropositivity among the working participants(aOR=1.760;95%CI:1.301-2.381,p=0.000 and aOR=1.384;95%CI:1.059-1.808,p=0.019,respectively).Additional factors showing association with seropositivity in the univariate analysis were:female gender,age group(15-39 years),higher educational level(preparatory and above),lack of environmental disinfection and having roommates at the workplace.There was a positive correlation between the titers of both antibodies.Age was weakly corre-lated with anti-S titer,while anti-N was significantly correlated with the number of protective measures applied by the participants.Both antibodies were significantly correlated with adult BMI,while both were significantly negatively correlated with the 展开更多
关键词 COVID-19 PREDICTORS SEROPREVALENCE anti-spike anti-nucleocapsid
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反脉冲时间依赖可塑性学习机制的光学实现 被引量:2
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作者 李强 王智 +5 位作者 崔粲 乐燕思 宋晓佳 孙翀翚 刘彪 吴重庆 《中国激光》 EI CAS CSCD 北大核心 2017年第5期222-226,共5页
突触可塑性为神经网络的学习机制提供了基础。基于单个半导体光放大器(SOA)的非线性偏振旋转(NPR)和交叉增益调制(XGM)效应实现了反脉冲时间依赖可塑性(anti-STDP)学习机制。通过调整SOA驱动电流,可以实现长时程增强窗口(LTP)和长时程... 突触可塑性为神经网络的学习机制提供了基础。基于单个半导体光放大器(SOA)的非线性偏振旋转(NPR)和交叉增益调制(XGM)效应实现了反脉冲时间依赖可塑性(anti-STDP)学习机制。通过调整SOA驱动电流,可以实现长时程增强窗口(LTP)和长时程抑制窗口(LTD)的高度和宽度调整,能更好地模拟神经网络。实验测量得到的anti-STDP曲线与生物系统中测量得到的学习曲线相吻合。使用该anti-STDP光路得到的学习曲线的时间窗口约为几百皮秒,其速度是人类大脑STDP学习机制的108倍。由于该anti-STDP光路系统简单,且SOA易于与其他器件集成,该anti-STDP光路可以用于实现大规模超快神经拟态计算系统。 展开更多
关键词 非线性光学 神经拟态计算 反脉冲时间依赖可塑性 半导体光放大器 光子脉冲神经元
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输电线路鸟害特点及防范措施 被引量:7
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作者 童忠辉 《青海电力》 2012年第2期1-3,共3页
通过对海北输电线路2006~2008年发生的鸟害事故进行分类统计及分析,对各种防鸟措施效果进行比较,提出了防治鸟害的管理和技术措施。
关键词 输电线路 鸟害 防鸟刺 风车式驱鸟器
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