Sex determination from the talus of Koreans by discriminant function analysis

The aims of this study were to investigate the sex discriminating potential of the talus in Koreans and compare this with other analyses in different populations. Statistical analyses were performed using data from nine measurements acquired from 140 tali (70 men, 70 women). The talus of Koreans is dimorphic between sexes in all measurements (p < 0.01). Discriminant function equations were generated by univariate, multivariate, and stepwise methods with a range of accuracy from 67.1 to 87.1%. Stepwise equations of other populations did not discriminate the sex of the Korean sample as accurately as each equation's own accuracies. The variables with high accuracy in this study are useful for sex determination of Koreans on the basis of confirmation of population specificity.     

Searching for Equilibrium: The Tenuous Nature of the Outcome Test

Based on Engel's critique of the outcome test and Persico and Todd's response, the underlying assumptions critical to the outcome test are summarized and discussed. It is argued that many of these assumptions are not met when applied to police search data. The key underlying assumption—the principle of equilibrium—is examined in detail, and several additional concerns are raised. Thereafter, the proper interpretations of outcome test analyses are reiterated, and discussion regarding the types of racial bias demonstrated by these analyses is further explored.     

注重考试环节提高教学质量

考试是教学的重要环节,不同的学科、不同的课程有不同的特点。命题应严格遵循全面考核,突出重点,理论联系实际,注重考查学生的实务操作能力这一原则。在试题内容上,应难易适度;在阅卷方式上,应根据题型的不同采用不同的判分标准;在应试技巧上,应教导学生要懂、吃透基础知识,学会总结典型题型。同时应加强学生考前模拟训练。     

STRtyper-10G系统9个STR基因座突变分析

目的观察和分析STRtyper-10G系统9个STR基因座的突变特点。方法在7 707例肯定亲子关系的案件中,统计使用STRtyper-10G试剂盒（9个STR基因座）检测发现的突变事件,判断突变等位基因的来源,计算各基因座的突变率,分析突变特点。结果在9个基因座上共发现118个突变事件,均为1步突变;平均突变率为1.69×10-3（95%CI 1.40×10-3~2.03×10-3）,各基因座的突变率介于0.78×10-3~2.84×10-3,父、母来源突变比例为9.64∶1;短、中、长等位基因的突变比值约为1∶8∶3,增加和减少重复单位的突变比值为1.29∶1。结论 9个基因座的突变率存在显著差异,实际检案时应结合各基因座的突变率进行PI值计算更为科学。     

Fingerprint error rate on close non‐matches

The accuracy of fingerprint identifications is critically important to the administration of criminal justice. Accuracy is challenging when two prints from different sources have many common features and few dissimilar features. Such print pairs, known as close non‐matches (CNMs), are increasingly likely to arise as ever‐growing databases are searched with greater frequency. In this study, 125 fingerprint agencies completed a mandatory proficiency test that included two pairs of CNMs. The false‐positive error rates on the two CNMs were 15.9% (17 out of 107, 95% C.I.: 9.5%, 24.2%) and 28.1% (27 out of 96, 95% C.I.: 19.4%, 38.2%), respectively. These CNM error rates are (a) inconsistent with the popular notion that fingerprint evidence is nearly infallible, and (b) larger than error rates reported in leading fingerprint studies. We conclude that, when the risk of CNMs is high, the probative value of a reported fingerprint identification may be severely diminished due to an elevated false‐positive error risk. We call for additional CNM research, including a replication and expansion of the present study using a representative selection of CNMs from database searches.     

人体组织ABO血型检测方法的研究

探讨人体组织ABO血型检测方法。对已知ABO血型尸体的不同组织,用红细胞粘连试验、吸收—抑制试验和吸收－解离试验进行ABO血型测定。12例尸体的16种组织中均检出与尸体血痕相同的ABH物质。对不同温度保存的组织块进行ABH物质检测的结果显示,4℃保存的组织ABH物质的检出时间长于室温,空腔脏器的检出时间短于实质脏器。三种方法中,红细胞粘连试验简单易行,适用于基层单位,吸收－抑制试验用于组织块的测定时优于吸收－解高试验。     

VNTR D17530位点多态性在亲子鉴定中的应用

运用微量热启动PCR技术,对20例正常家系的遗传学分析,证实D17530位点的遗传符合孟德尔遗传规律,表现为简单的共显性遗传。同时,对100例亲子鉴定案例进行回顾性分析研究,证明D17S30位．在多态性可应用于我国法医学亲子鉴定。根据D17S30位点基因频率估算的排除概率（74．04％）与其实际排除能力（80．00％）无显著差异。在15倒排除亲子关系的案例中,有2例由D17S30位点单独取得排除证据。D17S30位点是法医学上有重要意义的遗传学标记,可用于亲子鉴定。     

Evaluating the sensitivity,stability, and cross-reactivity of commercial fentanyl immunoassay test strips

Illicit fentanyl has flooded the United States' drug market, increasing the risk of overdose and poisonings throughout the general population and accidental exposure among law enforcement officers confiscating the increasing number of seizures. Fentanyl test strips (FTS) are used to obtain presumptive information about the presence of fentanyl in a suspected sample. However, their adoption by law enforcement personnel and seized-drug analysts has been limited because most products are advertised for urine testing, not for assays using water solutions. This study presents an evaluation of four commercial FTS: Rapid Response from BTNX, Inc.; T-Dip Fentanyl (FTY) Urine Dip Cards obtained from Amazon.com ; Premier BioDip FYL10 from Premier Biotech Inc.; and MobileDetect Fentanyl strips from DetectaChem, Inc. Performance characteristics curves were used to compare the products' sensitivity, showing that all can reliably detect fentanyl in aqueous solutions at concentrations below 1 μg/mL, with some of the tests able to reliably detect the drug at 200 ng/mL. A stability study demonstrates the performance of all four FTS brands was only slightly affected after 30 days of storage at two extreme environmental conditions. Fentanyl-related substances are also evaluated using the Rapid Response FTS, which showed high cross-reactivity with para-fluorofentanyl and acetylfentanyl, but lower with ortho-chlorofentanyl, carfentanil, and 4-ANPP. Users should be aware that FTS may give false-negative results even when potentially dangerous levels of carfentanil are present. When testing other common drugs, adulterants, and diluents frequently encountered in seized tablets, concentration-dependent results were obtained and multiple instances of false positives were recorded.     

ID‐Check: Online Concealed Information Test Reveals True Identity

The Internet has already changed people's lives considerably and is likely to drastically change forensic research. We developed a web‐based test to reveal concealed autobiographical information. Initial studies identified a number of conditions that affect diagnostic efficiency. By combining these moderators, this study investigated the full potential of the online ID‐check. Participants (n = 101) tried to hide their identity and claimed a false identity in a reaction time‐based Concealed Information Test. Half of the participants were presented with personal details (e.g., first name, last name, birthday), whereas the others only saw irrelevant details. Results showed that participants′ true identity could be detected with high accuracy (AUC = 0.98; overall accuracy: 86–94%). Online memory detection can reliably and validly detect whether someone is hiding their true identity. This suggests that online memory detection might become a valuable tool for forensic applications.     

Detection of Diatoms by a Combination of Membrane Filtration and Transparentness,

Diagnosis of drowning remains a difficult issue in current forensic sciences. A large number of diatoms were lost by removing the supernatant after centrifugation in the conventional forensic diatom test. We developed a novel membrane filtration method to enrich diatoms from samples. A new solution using different ratios of acetic acid and eugenol is prepared to make the membrane transparent. These processes allow the diatom‐containing membrane to be visualized and identified easily by light microscopy. The tissues contaminated by water rich in diatoms were detected by the new method for the recovery of diatoms. Eleven drowning cases were analyzed by both the new method and the conventional method to compare the sensitivity of both methods. The recovery of the novel diatom test method was 54.2 ± 23.1%. The positive rate of the novel method has been proven to be superior to the conventional method in the diagnosis of drowning.