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181.
未来二十年辽宁流动人口犯罪的发展变化预测   总被引:1,自引:0,他引:1  
未来二十年,辽宁流动人口犯罪将继续保持增长势头,上升比率会随政府相关政策调整有所下降;侵财类案件仍在各类案件中处于高发势头,伤害类案件会有所上升;团伙犯罪及重大、恶性案件的构成比例将有所增加。面对这种发展趋势,形势不容乐观。  相似文献   
182.
大鼠脑挫伤后脑组织COX-1/COX-2的表达   总被引:6,自引:1,他引:6  
目的 观察脑损伤后COX 1和COX 2蛋白表达及其时序性变化 ,探讨脑损伤的分子机制及法医学脑损伤时间推断。方法 以自由落体撞击雄性SD大鼠右顶叶制备脑挫伤模型 ,用免疫组织化学SP法处理脑组织检材 ,观察不同时间 ( 1、 3、 5、 7、 14d)脑组织COX 1/COX 2蛋白的表达情况。结果 正常及手术对照组大鼠 ,脑组织内有低水平的COX 1/COX 2表达 ;脑挫伤后 1~ 5d ,大鼠脑组织内COX 1表达逐渐增加 ,14d时仍维持在高表达水平 ;脑挫伤后 1~ 3d ,大鼠脑组织皮质内COX 2表达逐渐增加 ,1d时海马COX 2表达达高峰。结论 脑挫伤后可诱导COX 1/COX 2蛋白在脑内表达 ,并呈现出时序性变化。  相似文献   
183.
由于升学、就业、社会保障等方面存在的差别待遇,户籍在社会群体的分野中发挥重要作用。在犯罪学中将流动人群作为研究犯罪成因和防控的特定社会群体,有着现实的意义。未成年人犯罪问题日益为社会所关注,而流动人群中的未成年人受到所处环境等因素的影响,犯罪呈高发、上升态势,严重影响未成年人的身心健康和社会稳定。除了从犯罪遏制力、社区矫正等方面探讨流动人群未成年人犯罪的预防与控制外,我们还应结合流动人群未成年人的特殊性,采取必要的辅助手段。  相似文献   
184.
    
Dental development can be used to estimate age for forensic purposes. However, most of the currently available methods are less reliable for the Indonesian population due to population variability. This study presents a new method and evaluates other methods that utilize dental development to estimate the age of Indonesian people. Panoramic radiographs of 304 young Indonesian people aged 5–23 years old were analysed for deciduous tooth root resorption, permanent tooth calcification, and eruption. The extent of tooth root resorption was determined based on AlQahtani’s modified Moorrees et al. method. Tooth calcification was classified based on a modified Demirjian et al. method. Tooth eruption was evaluated based on AlQahtani’s modified Bengston system. The sequence of tooth root resorption, and permanent tooth calcification and eruption were grouped into 19 age categories (from 5–23 years old) in an atlas. The differences between males and females, between maxillary and mandibular teeth, and between right and left teeth were also analysed. There were minimal significant differences of tooth development between males and females, and between the right and left teeth (P > 0.05), while the maxillary and mandibular dental development was significantly different (P < 0.05). The newly developed atlas showed the development of the right side of maxillary and mandibular tooth of combined sex of Indonesian population. Another 34 panoramic radiographs of known-age and sex individuals from Indonesia were assessed using the newly developed Atlas of Dental Development in the Indonesian Population, Ubelaker’s Dental Development Chart, The London Atlas of Human Tooth Development and Eruption by AlQahtani, and the Age Estimation Guide-Modern Australia population by Blenkin-Taylor. Accuracy was assessed by comparing estimated age to actual chronological age using the Bland-Altmand test. Results show that the smallest range of error was found in the Atlas of Dental Development in the Indonesian Population (−0.969 to 1.210 years), followed by The London Atlas of Human Tooth Development and Eruption by AlQahtani (−2.013 to 1.990 years), the Age Estimation Guide-Modern Australia population by Blenkin-Taylor (−2.495 to 2.598 years), and the Dental Development Chart by Ubelaker (−2.960 to 3.289 years). These findings show that the Atlas of Dental Development constructed in this study performs better than the other three methods and presents greater accuracy of age estimation in the Indonesian population.

Key points

  • Dental development such as deciduous tooth root resorption, permanent tooth calcification, and tooth eruption can be used to estimate age for forensic purposes.
  • The development of the teeth are influenced by genetic, ethnicity, and sex, therefore an age estimation method must be constructed based on the same population.
  • There were minimal significant differences in tooth development between male and female, and between right and left teeth, but there was significant difference between maxillary and mandibular teeth.
  • The Atlas of Dental Development in the Indonesian Population constructed in this study allowed more accurate age estimation of the Indonesian sample than the other methods tested.
Supplemental data for this article are available online at https://doi.org/10.1080/20961790.2021.1886648.  相似文献   
185.
    
In this research, genotyping data of 43 InDel loci in 311 Han individuals in Ankang City, Shaanxi Province, China were detected using a self-developed five-dye multiplex amplification panel. The allelic frequencies and forensic parameters of all InDel loci were calculated. The combined power of discrimination and probability of exclusion values were 0.999 999 999 999 999 998 827 39 and 0.999 887 424, respectively, which demonstrated that this 43-InDel panel was powerful for individual identifications in Ankang Han population. Moreover, genetic distances, pairwise FST values, principal component analyses, phylogenetic trees and STRUCTURE analyses were performed to investigate the genetic affinities between Ankang Han and reference groups. Population genetic investigations indicated that Ankang Han population had a close genetic relationship with Southern Han population compared with other reference groups.  相似文献   
186.
    
《Science & justice》2022,62(3):288-309
Sex estimation standards are population specific however, we argue that machine learning techniques (ML) may enhance the biological sex determination on trans-population application. Linear discriminant analysis (LDA) versus nine ML including quadratic discriminant analysis (QDA), support vector machine (SVM), Decision Tree (DT), Gaussian process (GPC), Naïve Bayesian (NBC), K-Nearest Neighbor (KNN), Random Forest (RFM) and Adaptive boosting (Adaboost) were compared. The experiments involve two contemporary populations: Turkish (n = 300) and Egyptian populations (n = 100) for training and validation, respectively. Base models were calibrated using isotonic and sigmoid calibration schemes. Results were analyzed at posterior probabilities (pp) thresholds >0.95 and >0.80. At pp = 0.5, ML algorithms yielded comparable accuracies in the training (90% to 97%) and test sets (81% to 88%) which are not modified after employing the calibration techniques. At pp >0.95, the raw RFM, LDA, QDA, and SVM models have shown the best performance however, calibration techniques improved the performance of various classifier especially NBC and Adaboost. By contrast, the performance of GPC, KNN, QDA models worsened by calibration. RFM has shown the best performance among all models at both thresholds whereas LDA benefited the best from using both calibration methods at pp >0.80. Complex ML models are not necessarily achieving better performance metrics. LDA and QDA remain the fastest and simplest classifiers. We demonstrated the capability of enhancing sex estimation using ML on an independent population sample however, differences in the underlying probability distribution generated by models were detected which warranted more cautious application by forensic practitioners.  相似文献   
187.
    
In the present study the genetic variation of different Peruvian populations was investigated. The samples for this study were obtained from 669 individuals distributed among 11 populations from Peru. All samples were analyzed using 23 autosomal STR markers. The Arlequin v3.5.2.2 software was used to determine the genetic distances (Fst) of the studied populations. Notable population substructure was detected between some populations.  相似文献   
188.
    
We investigated the forensic efficacy of the 30 insertion/deletion (Indel) markers included in the Qiagen Investigator® DIPplex kit in 529 Pakistani individuals from five major subpopulations in Pakistan (Punjabi, Pashtun, Sindhi, Saraiki, and Baloch). In the Sindhi population, the distribution of HLD81 and HLD97 alleles deviated from Hardy-Weinberg equilibrium after Bonferroni correction. The combined match probability ranged from 2.0E-12 (Pashtun and Baloch) to 1.0E-12 (Sindhi), and the mean paternity exclusion power varied from 0.995 (Punjabi, Sindhi, and Saraiki) to 0.996 (Pashtun and Baloch). The high combined power of discrimination (0.999 999 999 999 97) and low combined match probability (1.7E-12) for all subpopulations studied support the utility of the 30 Indel markers for forensic identification in the studied subpopulations. The allele frequencies of the Indel markers in the Pakistani subpopulations were compared with those from 18 other populations. The results show that the populations clustered according to geography. The subpopulations investigated in this work showed a close genetic relationship with others from Pakistan, as well as with South Central Asian and Middle Eastern populations. The results suggest that the Investigator® DIPplex kit can be useful as a supplementary tool for human identification in the five Pakistani subpopulations investigated in this study.Supplemental data for this article is available online at https://doi.org/10.1080/20961790.2021.1933366 .  相似文献   
189.
Likelihood ratios are necessary to properly interpret mixed stain DNA evidence. They can flexibly consider alternate hypotheses and can account for population substructure. The likelihood ratio should be seen as an estimate and not a fixed value, because the calculations are functions of allelic frequency estimates that were estimated from a small portion of the population. Current methods do not account for uncertainty in the likelihood ratio estimates and are therefore an incomplete picture of the strength of the evidence. We propose the use of a confidence interval to report the consequent variation of likelihood ratios. The confidence interval is calculated using the standard forensic likelihood ratio formulae and a variance estimate derived using the Taylor expansion. The formula is explained, and a computer program has been made available. Numeric work shows that the evidential strength of DNA profiles decreases as the variation among populations increases.  相似文献   
190.
Abstract: This study assesses the predictive value of anterior sacral curvature for sex estimation from skeletonized remains. Sacra from a sample of 125 American adults of known age and sex were examined. Nine measurements describing anterior sacral curvature were used in the analysis. Statistical treatment of the data included univariate statistics and discriminant function analysis for sex classification. A bootstrap validation method was employed to assess the classification error rates. Sacral curvature was significantly greater in men than in women at the level of the S2–S3 and S3–S4 articulations (p < 0.05). Correct classification estimates for the discriminant function range from 66–72%. Although sexually dimorphic, metric observations of sacral curvature are not as reliable at predicting sex as other skeletal elements. Anterior sacral curvature should only be used for sex estimation in the absence of other, more reliable, indicators.  相似文献   
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