Fingerprints with similar morphological characteristics but from different individuals can lead to errors in individual identification, especially when dealing with large databases containing millions of fingerprints. To address this issue and enhance the accuracy of similar fingerprint identification, the use of the likelihood ratio (LR) model for quantitative evaluation of fingerprint evidence has emerged as an effective research method. In this study, the LR fingerprint evidence evaluation model was established by using mathematical statistical methods, such as parameter estimation and hypothesis testing. This involved various steps, including database construction, scoring, fitting, calculation, and visual evaluation. Under the same-source conditions, the optimal parameter methods selected by different number of minutiae are gamma and Weibull distribution, while normal, Weibull, and lognormal distributions were the fitting parameters selected for minutiae configurations. The fitting parameters selected by different number of minutiae under different-source conditions are lognormal distribution, and the parameter methods selected for different minutiae configurations include Weibull, gamma, and lognormal distributions. The results of the LR model showed increased accuracy as the number of minutiae increased, indicating strong discriminative and corrective power. However, the accuracy of the LR evaluation based on different configurations was comparatively lower. In addition, the LR models with different numbers of minutiae outperformed those with different minutiae configurations. Our study shows that the use of LR models based on parametric methods is favoured in reducing the risk of fingerprint evidence misidentification, improving the quantitative assessment methods of fingerprint evidence, and promoting fingerprint identification from experience to science.
UNASSIGNED: Likelihood ratio (LR) method based on parameter estimation was applied to scientific evaluation of fingerprint evidence with excellent discriminatory and calibration capabilities.Both the number of minutiae and configuration of minutiae have significant effects on the score-based LR method.Fingerprints from the same source contain many different patterns of deformation.Databases containing 10 million fingerprints from different sources have been used for building the LR model.

Introduction: The likelihood ratio (LR) can be an efficient means of distinguishing various relationships in forensic fields. However, traditional list-based methods for derivation and presentation of LRs in distant or complex relationships hinder code editing and software programming. This paper proposes an approach for a unified formula for LRs, in which differences in participants\' genotype combinations can be ignored for specific identification. This formula could reduce the difficulty of by-hand coding, as well as running time of large-sample-size simulation. Methods: The approach is first applied to a problem of kinship identification in which at least one of the participants is alleged to be inbred. This can be divided into two parts: i) the probability of different identical by descent (IBD) states according to the alleged kinship; and ii) the ratio of the probability that specific genotype combination can be detected assuming the alleged kinship exists between the two participants to the similar probability assuming that they are unrelated, for each state. For the probability, there are usually recognized results for common identification purposes. For the ratio, subscript letters representing IBD alleles of individual A\'s alleles are used to eliminate differences in genotype combinations between the two individuals and to obtain a unified formula for the ratio in each state. The unification is further simplified for identification cases in which it is alleged that both of the participants are outbred. Verification is performed to show that the results obtained with the unified and list-form formulae are equivalent. Results: A series of unified formulae are derived for different identification purposes, based on which an R package named KINSIMU has been developed and evaluated for use in large-size simulations for kinship analysis. Comparison between the package with two existing tools indicated that the unified approach presented here is more convenient and time-saving with respect to the coding process for computer applications compared with the list-based approach, despite appearing more complicated. Moreover, the method of derivation could be extended to other identification problems, such as those with different hypothesis sets or those involving multiple individuals. Conclusion: The unified approach of LR calculation can be beneficial in kinship identification field.

Multi-model score fusion was considered a bottleneck problem in forensic face identification. While the score distribution of different face models varies greatly, the existing score processing methods cannot achieve accurate alignment. This paper proposed a score fusion framework named fine alignment and flexible fusion framework (FAFF). In FAFF, we took score-based likelihood ratios as the reference values to align the similarity scores generated by different face models. First, we set up a unified calibration test workflow based on the forensic likelihood ratio test. Then, 3 LLR anchor-based methods (LLRBA1, LLRBA2, and LLRBA3) and LLR curve-based methods (LLRBC) were proposed. Finally, we conducted fusion experiments on four face models (VGGface, Facenet, Arcface, and SFace). The experimental results show that on the CelebA dataset, compared with the existing MOEBA and PAN methods, LLRBC increased the TPR@ 10-7 FPR by 175.4 % and 162.9 %, and LLRBA increased by 55.6 % and 48.5 %.

Bullet projectiles are often found in shooting crime scenes and can help identify the cartridges used in shooting events. The most conclusive way to link a fired projectile to a firearm is by identifying the unique markings of the barrel on the projectile or case. But in circumstances where the investigation of striation marks is impossible, lead isotope ratio signature analysis of projectile fragments can facilitate building the linkage of the suspect, the cartridge used and the victim. This work presents a shooting incident happened in a hunting field, where a hunting guide was shot to death. A tiny lead projectile fragment was collected from the victim\'s head. Pb isotope ratios measured by laser ablation multicollector inductively coupled plasma mass spectrometry (LA-MC-ICPMS) were used to make comparisons between the fragment and the shots seized from two suspects. Additionally, a reference dataset comprising 50 lead bullet projectiles from various manufacturers was characterized using LA-MC-ICPMS. The evaluation of the comparison was carried out by multivariate likelihood ratio (LR) computations based on the reference dataset. The lead isotope ratio and likelihood ratio evaluation methods helped infer the source of the fragment and were highly supportive in the shooting incident investigation.

OBJECTIVE: To calculate the likelihood ratios of incest cases using identity by descent (IBD) patterns.
METHODS: The unique IBD pattern was formed by denoting the alleles from the members in a pedigree with a same digital. The probability of each IBD pattern was obtained by multiplying the prior probability by the frequency of non-IBD alleles. The pedigree likelihoods of incest cases under different hypotheses were obtained by summing all IBD pattern probabilities, and the likelihood ratio(LR) was calculated by comparing the likelihoods of different pedigrees.
RESULTS: The IBD patterns and the formulae of calculating LR for father-daughter incest and brother-sister incest were obtained.
CONCLUSIONS: The calculations of LR for incest cases were illustrated based on IBD patterns.
目的: 用血缘一致性（identity by descent，IBD）型式计算乱伦案件的似然比。方法: 先用相同的数字表示家系成员中IBD的等位基因以组成IBD型式，然后用先验概率乘以非IBD等位基因频率得出各个IBD型式概率。将家系的所有IBD型式概率相加即可得到乱伦案不同假设下的家系概率，比较不同家系概率计算似然比。结果: 获得了父女乱伦和全同胞乱伦案的IBD型式及这两种案例的似然比计算公式。结论: 阐明了基于IBD型式计算乱伦案似然比的方法。.

OBJECTIVE: To derive the paternity index (PI) calculation formula of the alleged father (AF) when the AF is a relative (parent/child, siblings, grandparent/grandchild, uncle/nephew, first cousins) of the child\'s biological mother.
METHODS: For the case when the AF is related to the child\'s biological mother, the existence of the relationship in the numerator and denominator hypothesis of PI was considered. The genotype frequency of the AF was calculated by using the frequency formula in which the mother\'s genotype was considered, while the random male in the denominator was substituted as another relative of the mother\'s same rank. The PI calculation formula was derived to eliminate the effect of the relationship between AF and the child\'s biological mother.
RESULTS: When the AF and the biological mother have first, second and tertiary kinship, a more conservative PI was obtained from the PI calculation formula derived in this study compared with the PI calculation method which did not consider kinship.
CONCLUSIONS: The calculation method provided in this study can eliminate the effect of the relation of the AF and mother on the PI in incest cases, to obtain more accurate and conservative identification conclusions.
目的: 推导当可疑父与孩子生母具有亲缘关系（亲子、全同胞、爷孙、叔侄、一代表亲）时，可疑父的PI计算公式。方法: 针对可疑父与孩子生母存在亲缘关系的情况，在PI的分子和分母假设中均考虑亲缘关系的存在，使用考虑母亲基因型的频率公式计算可疑父的基因型频率，同时将分母中的随机男子被替代为母亲的另一个同等级亲属，推导出消除可疑父和孩子生母亲缘关系影响的PI计算公式。结果: 当可疑父与生母具有一、二、三级亲缘关系时，与不考虑亲缘关系的PI计算方法相比，使用本研究推导出的PI计算公式可以获得更保守的PI。结论: 本研究提供的计算方法可以消除乱伦案中可疑父与母亲的亲缘关系对PI的影响，从而获得更加准确和保守的鉴定意见。.

OBJECTIVE: To compare the application value of the likelihood ratio (LR) method and identity by state (IBS) method in the identification involving half sibling relationships, and to provide a reference for the setting of relevant standards for identification of half sibling relationship.
METHODS: (1) Based on the same genetic marker combinations, the reliability of computer simulation method was verified by comparing the distributions of cumulated identity by state score (CIBS) and combined full sibling index in actual cases with the distributions in simulated cases. (2) In different numbers of three genetic marker combinations, the simulation of full sibling, half sibling and unrelated individual pairs, each 1 million pairs, was obtained; the CIBS, as well as the corresponding types of cumulative LR parameters, were calculated. (3) The application value of LR method was compared with that of IBS method, by comparing the best system efficiency provided by LR method and IBS method when genetic markers in different amounts and of different types and accuracy were applied to distinguish the above three relational individual pairs. (4) According to the existing simulation data, the minimum number of genetic markers required to distinguish half siblings from the other two relationships using different types of genetic markers was estimated by curve fitting.
RESULTS: (1) After the rank sum test, under the premise that the real relationship and the genetic marker combination tested were the same, there was no significant difference between the simulation method and the results obtained in the actual case. (2) In most cases, under the same conditions, the system effectiveness obtained by LR method was greater than that by IBS method. (3) According to the existing data, the number of genetic markers required for full-half siblings and half sibling identification could be obtained by curve fitting when the system effectiveness reached 0.95 or 0.99.
CONCLUSIONS: When distinguishing half sibling from full sibling pairs or unrelated pairs, it is recommended to give preference to the LR method, and estimate the required number of markers according to the identification types and the population data, to ensure the identification effect.
目的: 比较似然比（likelihood ratio，LR）法和状态一致性（identity by state，IBS）法在半同胞关系鉴定中的应用价值，为制定半同胞鉴定相关规范提供参考。方法: （1）基于相同的遗传标记组合，比较实际案例与计算机模拟案例的累计状态一致性评分（cumulated identity by state score，CIBS）与累积全同胞关系指数分布，验证计算机模拟方法的可信度；（2）模拟获得全同胞、半同胞、无关个体对各100万对在不同数量的三种类型遗传标记上的分型，分别计算CIBS和相应类型的累积LR参数；（3）比较基于不同数据、不同种类的遗传标记、应用不同准确度标准区分上述三种关系个体对时，LR法和IBS法所能提供的最佳系统效能，以比较两种方法在上述鉴定中的应用价值；（4）根据已有模拟数据，以曲线拟合的方式估计应用不同类型遗传标记鉴别半同胞与另两种关系个体对所需的最低遗传标记数目。结果: （1）经秩和检验，在真实关系和检验的遗传标记组合相同的前提下，模拟方法与实际案例所得结果差异无统计学意义；（2）多数情况下，在其他条件设置相同时，LR法的系统效能大于IBS法；（3）基于现有数据，可以通过曲线拟合的方式得到全-半同胞鉴定和半同胞鉴定在系统效能达到0.95或0.99时所需遗传标记的数目。结论: 在进行甄别全同胞对和半同胞对或甄别半同胞对和无关个体对的鉴定时，推荐优先使用LR法，并根据拟进行的鉴定类型和基于的人群数据估计所需遗传标记数目，以保证鉴定效果。.

Kinship testing is widely needed in forensic science practice. This paper reviews the definitions of common concepts, and summarizes the basic principles, advantages and disadvantages, and application scope of kinship analysis methods, including identity by state (IBS) method, likelihood ratio (LR) method, method of moment (MoM), and identity by descent (IBD) segment method. This paper also discusses the research hotspots of challenging kinship testing, complex kinship testing, forensic genetic genealogy analysis, and non-human biological samples.
亲缘关系鉴定在司法鉴定实践中有广泛的应用需求。本文梳理了亲缘关系相关的概念，综述了状态一致性法、似然比法、矩量法和血缘一致性片段法等亲缘关系分析方法的基本原理、优缺点和应用范围，并对疑难生物检材的亲缘关系鉴定、复杂亲缘关系鉴定、法医学系谱分析、非人源生物检材等研究热点进行了讨论。.

Endobronchial ultrasound bronchoscopy (EBUS) and needle confocal laser endomicroscopy (nCLE) are techniques for screening benign and malignant lesions of the hilar and mediastinal lymph node (HMLN). This study investigated the diagnostic potential of EBUS, nCLE, and combined EBUS and nCLE in HMLN lesions. We recruited 107 patients with HMLN lesions who were examined by EBUS and nCLE. A pathological examination was performed, and the diagnostic potential of EBUS, nCLE, and combined EBUS-nCLE approach was analyzed according to the results. Among the 107 cases of HMLN lesions, 43 cases were benign and 64 cases were malignant on pathological examination, 41 cases were benign and 66 cases were malignant on EBUS examination; 42 cases were benign and 65 cases were malignant on nCLE examination; 43 cases were benign and 64 cases were malignant on combined EBUS-nCLE examination. The combination approach had 93.8% sensitivity, 90.7% specificity, and 0.922 area under the curve, which was higher than those of EBUS (84.4%, 72.1%, and 0.782, respectively) and nCLE diagnosis (90.6%, 83.7%, and 0.872, respectively). The combination approach had a higher positive predictive value (0.908), negative predictive value (0.881), and positive likelihood ratio (10.09) than that of EBUS (0.813, 0.721, and 3.03, respectively) and nCLE (0.892, 0.857, and 5.56, respectively), whereas, the negative likelihood ratio was lower than that for EBUS (0.22) and nCLE (0.11). No serious complications occurred in patients with HMLN lesions. To summarize, the diagnostic efficacy of nCLE was better than EBUS. The EBUS-nCLE combination is a suitable approach for diagnosing HMLN lesions.

Kinship testing plays critical roles in criminal investigations, missing person searches, civil disputes, as well as identifying disaster victims. The existing commonly used short tandem repeat (STR) loci have limited effectiveness in the identification of second-degree and more distant kinships. In this study, a total of 1993 SNP loci of 119 Chinese Han individuals from eight families were sequenced on the MGISEQ-2000RS platform. The system powers of this panel for kinship identifications were evaluated based on both the likelihood ratio (LR) and identical by state (IBS) methods. The results indicated that this panel could be used as an effective tool to kinship analyses including paternity testing, full sibling testing, second-degree kinships, and first cousin kinship analyses. Both the LR and IBS methods could be applied in distinguishing first-degree and second-degree pairs from unrelated individuals. Based on the 1993 SNP loci, LR>1000 and LR<0.001 are recommended as the thresholds of identifying first-cousin kinships from unrelated individuals, and the system power of such thresholds was 0.9470. Besides, kinship coefficients for different kinship pairs were estimated and then were used to predict the kinships for pairwise individuals. This panel performs an effective kinship inference power for the predictions of first-degree, second-degree kinships and unrelated individual pairs, while presenting low sensitivity in the prediction of first-cousin kinships.