常染色体STR鉴定同胞的应用探讨

【目的】探讨常染色体STR遗传标记鉴定两个体同胞关系的可行性。【方法】用PowerPlex^TM 16体系15个常染色体STR基因座检测50对全同胞、25对半同胞和50对无关个体，ITO法计算全同胞关系指数（PSI）、半同胞关系指数（HSI）和PSI：HSI值，比较3组两个体间等位基因匹配情况，并进行组间差异的x^2检验。【结果】全同胞的FSI均大于1；19对半同胞的HSI大于1；无关个体FSI均小于1；49对无关个体HSI小于1，1对为1．297。46对全同胞的FSI：HSI值大于1，22对半同胞的FSI：HSI值小于1。全同胞组两个体间1对等位基因全相同、半相同、全不同的基因座数平均值分别为6．06个、7．52个、1．42个；半同胞组分别为2．96个、8．48个、3．56个；无关个体组分别为1．24个、7．22个、6．54个。x^2检验3组两个体间1对等位基因全相同和全不同的基因座数差异有显著意义，半相同的基因座数差异无显著意义。【结论】PowerPlex^TM 16体系在全同胞一无关个体的鉴定中效率较高，在鉴定半同胞一无关个体或全同胞一半同胞时效率降低。全同胞一半同胞关系鉴定时，PSI：HSI值是一个较有效的指标：大于1倾向于为全同胞，小于1倾向于为半同胞

广东汉族人群D13S631 位点的多态性

【目的】调查D13S631 位点在广东汉族群体的多态性。【方法】PCR 扩增短串联重复(STR)位点D13S631 后, 用 不连续电泳系统进行分型。【结果】在227 个无关个体中共发现了6 个等位基因, 扩增片段为197 ～ 217 bp , 等位基因频率最 高为0.2907(201 bp), 最低为0.0903(197 bp)。杂合率、个体识别率和非父排除率分别为0.7885 , 0.9231 , 0.5543。家系分析 表明按孟德尔规律遗传。【结论】结果表明D13S631 是一个具有重要法医应用价值的位点

中国汉族群体DXS101 位点的多态性

【目的】调查X 染色体特异性位点DXS101 在中国汉族人群的多态性。【方法】利用PCR 和聚丙烯凝胶电泳对 短串联重复序列(short tandem repeat , STR)位点DXS101 进行分型, 并检验女性基因型频率分布是否符合Hardy-Weinberg 平 衡, 计算法医学常用各种概率。【结果】在147 名女性和150 名男性中国汉族无关个体共发现了8 个等位基因。等位基因的 频率分布在0.0133 ～ 0.2279 之间。正合检验表明女性的基因型频率分布符合Hardy-Weinberg 平衡。DXS101 的基因多样性 达0.8296, 女性和男性样本的个体识别率分别0.9474 和0.8277, 当母亲和女儿同时检验时, 非父排除率为0.8049。【结论】 DXS101 是一个高度多态性的系统, 适用于个人识别和女孩的亲权认定

Prediction of Energy Resolution in the JUNO Experiment

International audienceThis paper presents the energy resolution study in the JUNO experiment, incorporating the latest knowledge acquired during the detector construction phase. The determination of neutrino mass ordering in JUNO requires an exceptional energy resolution better than 3% at 1 MeV. To achieve this ambitious goal, significant efforts have been undertaken in the design and production of the key components of the JUNO detector. Various factors affecting the detection of inverse beta decay signals have an impact on the energy resolution, extending beyond the statistical fluctuations of the detected number of photons, such as the properties of liquid scintillator, performance of photomultiplier tubes, and the energy reconstruction algorithm. To account for these effects, a full JUNO simulation and reconstruction approach is employed. This enables the modeling of all relevant effects and the evaluation of associated inputs to accurately estimate the energy resolution. The study reveals an energy resolution of 2.95% at 1 MeV. Furthermore, the study assesses the contribution of major effects to the overall energy resolution budget. This analysis serves as a reference for interpreting future measurements of energy resolution during JUNO data taking. Moreover, it provides a guideline in comprehending the energy resolution characteristics of liquid scintillator-based detectors

JUNO Sensitivity on Proton Decay p→νˉK+p\to \bar\nu K^+ Searches

The Jiangmen Underground Neutrino Observatory (JUNO) is a large liquid scintillator detector designed to explore many topics in fundamental physics. In this paper, the potential on searching for proton decay in $p\to \bar\nu K^+$ mode with JUNO is investigated.The kaon and its decay particles feature a clear three-fold coincidence signature that results in a high efficiency for identification. Moreover, the excellent energy resolution of JUNO permits to suppress the sizable background caused by other delayed signals. Based on these advantages, the detection efficiency for the proton decay via $p\to \bar\nu K^+$ is 36.9% with a background level of 0.2 events after 10 years of data taking. The estimated sensitivity based on 200 kton-years exposure is $9.6 \times 10^{33}$ years, competitive with the current best limits on the proton lifetime in this channel

JUNO sensitivity on proton decay p → ν K + searches*

The Jiangmen Underground Neutrino Observatory (JUNO) is a large liquid scintillator detector designed to explore many topics in fundamental physics. In this study, the potential of searching for proton decay in the $p\to \bar{\nu} K^+$ mode with JUNO is investigated. The kaon and its decay particles feature a clear three-fold coincidence signature that results in a high efficiency for identification. Moreover, the excellent energy resolution of JUNO permits suppression of the sizable background caused by other delayed signals. Based on these advantages, the detection efficiency for the proton decay via $p\to \bar{\nu} K^+$ is 36.9% ± 4.9% with a background level of $0.2\pm 0.05({\rm syst})\pm$$0.2({\rm stat})$ events after 10 years of data collection. The estimated sensitivity based on 200 kton-years of exposure is $9.6 \times 10^{33}$ years, which is competitive with the current best limits on the proton lifetime in this channel and complements the use of different detection technologies