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171.
Guangwei Hou Ph.D Xianhua Jiang M.D. Yanyan Yang M.D. Fei Jia M.D. Qiang Li M.D. Jinling Zhao M.D. Fei Guo M.D. Limin Liu M.D. 《Journal of forensic sciences》2014,59(1):5-14
To develop a cost‐effective technique for single‐nucleotide polymorphism (SNP) genotyping and improve the efficiency to analyze degraded DNA, we have established a novel multiplex system including 21‐locus autosomal SNPs and amelogenin locus, which was based on allele‐specific amplification (ASA) and universal reporter primers (URP). The target amplicons for each of the 21 SNPs arranged from 63 base pair (bp) to 192 bp. The system was tested in 539 samples from three ethnic groups (Han, Mongolian, and Zhuang population) in China, and the total power of discrimination (TPD) and cumulative probability of exclusion (CPE) were more than 0.99999999 and 0.98, respectively. The system was further validated with forensic samples and full profiles could be achieved from degraded DNA and 63 case‐type samples. In summary, the multiplex system offers an effective technique for individual identification of forensic samples and is much more efficient in the analysis of degraded DNA compared with standard STR typing. 相似文献
172.
Paul Gill Ph.D. John Horgan Ph.D. Paige Deckert M.S. A.B.D. 《Journal of forensic sciences》2014,59(2):425-435
This article analyzes the sociodemographic network characteristics and antecedent behaviors of 119 lone‐actor terrorists. This marks a departure from existing analyses by largely focusing upon behavioral aspects of each offender. This article also examines whether lone‐actor terrorists differ based on their ideologies or network connectivity. The analysis leads to seven conclusions. There was no uniform profile identified. In the time leading up to most lone‐actor terrorist events, other people generally knew about the offender's grievance, extremist ideology, views, and/or intent to engage in violence. A wide range of activities and experiences preceded lone actors' plots or events. Many but not all lone‐actor terrorists were socially isolated. Lone‐actor terrorists regularly engaged in a detectable and observable range of activities with a wider pressure group, social movement, or terrorist organization. Lone‐actor terrorist events were rarely sudden and impulsive. There were distinguishable behavioral differences between subgroups. The implications for policy conclude this article. 相似文献
173.
Biao Li M.Sc. Peng Xie Ph.D. Ying‐min Guo B.Sc. Qing Fei B.Sc. 《Journal of forensic sciences》2014,59(2):543-549
In many criminal and civil cases in China, the most commonly questioned documents are those written with gel pen ink. An important task for forensic document examiners is to identify whether two or more ink entries in one or more documents were written with the same ink type. The identification of the age of gel ink entries made poses an important and difficult problem for forensic document examiners. In this paper, the volatile components of gel ink were determined and the gel ink was classified by gas chromatography with a flame ionization detector. Calibration curves were created to express the relationship between the content of volatile gel ink components and the age of gel ink entries stored under natural and UV‐induced aging conditions. The correspondence between the natural and UV‐induced aging conditions was also established. The experimental results showed that GC was useful in the analysis of black gel ink and applicable for determining the relative age of gel ink entries under certain conditions. 相似文献
174.
An HPLC‐DAD method was developed to detect and quantify a neonicotinoid insecticide acetamiprid (ATP) and its metabolite IM‐1‐2 in autopsy samples of a fatal intoxication case. The postmortem blood and tissue distribution of ATP and IM‐1‐2 was determined for the first time. The method showed acceptable precisions and recoveries with relative standard deviations of <10% for ATP level and 1.38 % for IM‐1‐2. The detection and quantification limits for ATP were 0.015 μg/mL and 0.030 μg/mL for blood and were 0.035 μg/g and 0.050 μg/g for liver samples, respectively. The mean contents of ATP were 0.79 μg/g in the liver, 47.35 μg/g in the stomach contents and 2.7 μg/mL in the blood. IM‐1‐2 content was 17.0 μg/g in the stomach contents. ATP and IM‐1‐2 were not detected in the urine. The presence of ATP and IM‐1‐2 in the samples was confirmed by GC‐MS. The method can be exploited in future forensic casework. 相似文献
175.
Edward M. Suzuki Ph.D. 《Journal of forensic sciences》2014,59(2):344-363
Chrome Yellow (PbCrO4·xPbSO4) was a common pigment in U.S. automobile OEM finishes for more than three decades, but in the early 1990s its use was discontinued. One of its main replacements was Bismuth Vanadate (BiVO4·nBi2MoO6, n = 0–2), which was commercially introduced in 1985, as this inorganic pigment also produces a very bright hue and has excellent outdoor durability. This paper describes the in situ identification of Bismuth Vanadate in automotive finishes using FT‐IR and dispersive Raman spectroscopy and XRF spectrometry. Some differentiation of commercial formulations of this pigment is possible based on far‐infrared absorptions, Raman data, and elemental analysis. The spectral differences arise from the presence or absence of molybdenum, the use of two crystal polymorphs of BiVO4, and differences in pigment stabilizers. Bismuth Vanadate is usually not used alone, and it is typically found with Isoindoline Yellow, hydrous ferric oxide, rutile, Isoindolinone Yellow 3R, or various combinations of these. 相似文献
176.
Alessandro Mameli M.S. Gavino Piras B.S. Giovanni Delogu Ph.D. 《Journal of forensic sciences》2014,59(2):470-473
A universal method allowing for DNA profiling from bones exposed to seawater has not been reported yet. This study refers on the identification of a body immersed in seawater for 8 months. The biological material for identification was the mandibular body, usually characterized by low success rates of DNA analysis. Initially, two extraction protocols were performed with negative results: one used for bones immersed in fresh water and a silica‐column procedure. A third protocol was performed, which combined the extraction of a higher amount of bone powder, the use of multi‐silica‐based extraction columns followed by a concentration step. This protocol allowed to obtain low copy number DNA and to generate a 12‐loci STR profile by combining conventional STR typing and mini‐STR technologies. This protocol could be suitable when human bones have been exposed to severe environmental conditions, and the available nuclear DNA is highly degraded and in low copy number. 相似文献
177.
Ina Fettig Ph.D. Simone Krüger Ph.D. Jan H. Deubel M.S. Martin Werrel M.S. Tina Raspe Christian Piechotta Ph.D. 《Journal of forensic sciences》2014,59(3):743-749
The chemical analysis of fire debris represents a crucial part in fire investigations to determine the cause of a fire. A headspace solid‐phase microextraction (HS‐SPME) procedure for the detection of ignitable liquids in fire debris using a fiber coated with a mixture of three different sorbent materials (Divinylbenzene/Carboxen/Polydimethylsiloxane, DVB/CAR/PDMS) is described. Gasoline and diesel fuel were spiked upon a preburnt matrix (wood charcoal), extracted and concentrated with HS‐SPME and then analyzed with gas chromatography/mass spectrometry (GC/MS). The experimental conditions—extraction temperature, incubation and exposure time—were optimized. To assess the applicability of the method, fire debris samples were prepared in the smoke density chamber (SDC) and a controlled‐atmosphere cone calorimeter. The developed methods were successfully applied to burnt particleboard and carpet samples. The results demonstrate that the procedure that has been developed here is suitable for detecting these ignitable liquids in highly burnt debris. 相似文献
178.
Raíssa Ananda Paim Strapasson Ph.D. Leandro Stocco Baccarin M.Sc. Rodolfo Francisco Haltenhoff Melani Ph.D. 《Journal of forensic sciences》2019,64(6):1633-1639
Prediction facial features from the skull are recurring theme on the forensic literature. The nose has been investigated since it has a significant role in facial recognition and the literature shows that there is not an universal method for nasal prediction. This study aimed to conduct a systematic review to analyze what are the most consistent techniques of nasal reconstruction. Primary studies describing or validating nasal reconstruction techniques in adults and published in journals of Forensic Sciences were included in this review. Tedeschi‐Oliveira's method positioned nasal tip with acceptable accuracy as Gerasimov's method. The Krogman's and Iscan's technique underestimated nasal projection in North Americans. The Prokopec's and Ubelaker's method obtained accuracy in Caucasoid. George's method presented results similar to reference standard in Caucasoid. In a supplementary way, studies are needed to accurately estimate the nasal width. 相似文献
179.
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. 相似文献
180.
Nemanja Vučković MSc Nikola Glođović BSc Željko Radovanović PhD Đorđe Janaćković PhD Nikola Milašinović PhD 《Journal of forensic sciences》2021,66(1):149-160
Most chemical and physical methods employed in visualizing latent marks have shown detrimental effects on human health and, therefore, some research groups have directed their attention to the utilization of various (bio)polymers with the aforementioned purpose. Although chitosan is widely used in medicine, pharmacy, food, and drug delivery systems, there are very few studies that address this biopolymer utilization in forensic applications, such as the detection of latent fingerprints. We used chitosan crosslinked with sodium tripolyphosphate and conjugated with L‐lysine to enhance the visualization of latent fingerprints, due to its ability to interact with fingerprint sweat residues. These conjugates were prepared using different (w/w) amounts of chitosan and tripolyphosphate (6/1; 4/1; 1/1; 1/4; and 1/6), and those with the most promising results (i.e., 6/1 formulation) were investigated in detail. Fourier transform infrared (FT‐IR) spectroscopy confirmed interactions between components of the systems. Optical microscopy and scanning electron microscope (SEM) analysis showed that prepared powder formulations were uniform in size and confirmed that chitosan/tripolyphosphate/lysine conjugates bind easily to the sweat and lipid residues present in the latent fingerprints. The testing of prepared conjugates demonstrated the potential of these systems as bio‐based powder substitution for commercially available powders. 相似文献