Evaluation of forensic DNA mixture evidence: protocol for evaluation, interpretation, and statistical calculations using the combined probability of inclusion.

PubMed

Bieber, Frederick R; Buckleton, John S; Budowle, Bruce; Butler, John M; Coble, Michael D

2016-08-31

The evaluation and interpretation of forensic DNA mixture evidence faces greater interpretational challenges due to increasingly complex mixture evidence. Such challenges include: casework involving low quantity or degraded evidence leading to allele and locus dropout; allele sharing of contributors leading to allele stacking; and differentiation of PCR stutter artifacts from true alleles. There is variation in statistical approaches used to evaluate the strength of the evidence when inclusion of a specific known individual(s) is determined, and the approaches used must be supportable. There are concerns that methods utilized for interpretation of complex forensic DNA mixtures may not be implemented properly in some casework. Similar questions are being raised in a number of U.S. jurisdictions, leading to some confusion about mixture interpretation for current and previous casework. Key elements necessary for the interpretation and statistical evaluation of forensic DNA mixtures are described. Given the most common method for statistical evaluation of DNA mixtures in many parts of the world, including the USA, is the Combined Probability of Inclusion/Exclusion (CPI/CPE). Exposition and elucidation of this method and a protocol for use is the focus of this article. Formulae and other supporting materials are provided. Guidance and details of a DNA mixture interpretation protocol is provided for application of the CPI/CPE method in the analysis of more complex forensic DNA mixtures. This description, in turn, should help reduce the variability of interpretation with application of this methodology and thereby improve the quality of DNA mixture interpretation throughout the forensic community.

Accuracy Rates of Sex Estimation by Forensic Anthropologists through Comparison with DNA Typing Results in Forensic Casework.

PubMed

Thomas, Richard M; Parks, Connie L; Richard, Adam H

2016-09-01

A common task in forensic anthropology involves the estimation of the biological sex of a decedent by exploiting the sexual dimorphism between males and females. Estimation methods are often based on analysis of skeletal collections of known sex and most include a research-based accuracy rate. However, the accuracy rates of sex estimation methods in actual forensic casework have rarely been studied. This article uses sex determinations based on DNA results from 360 forensic cases to develop accuracy rates for sex estimations conducted by forensic anthropologists. The overall rate of correct sex estimation from these cases is 94.7% with increasing accuracy rates as more skeletal material is available for analysis and as the education level and certification of the examiner increases. Nine of 19 incorrect assessments resulted from cases in which one skeletal element was available, suggesting that the use of an "undetermined" result may be more appropriate for these cases. Published 2016. This article is a U.S. Government work and is in the public domain in the USA.

Isolating cells from female/male blood mixtures using florescence in situ hybridization combined with low volume PCR and its application in forensic science.

PubMed

Feng, Lei; Li, Cai-Xia; Han, Jun-Ping; Xu, Cheng; Hu, Lan

2015-11-01

To obtain single-source short tandem repeat (STR) profiles in trace female/male blood mixture samples, we combined florescence in situ hybridization (FISH), laser microdissection, and low volume PCR (LV-PCR) to isolate male/female cells and improve sensitivity. The results showed that isolation of as few as 10 leukocytes was sufficient to yield full STR profiles in fresh female or male blood samples for 32 independent tests with a low additional alleles rate (3.91%) and drop-out alleles rate (5.01%). Moreover, this procedure was tested in two fresh blood mixture series at three ratios (1:5, 1:10, and 1:20), two mock female/male blood mixture casework samples, and one practical casework sample. Male and female STR profiles were successfully detected in all of these samples, showing that this procedure could be used in forensic casework in the future.

Soil DNA metabarcoding and high-throughput sequencing as a forensic tool: considerations, potential limitations and recommendations.

PubMed

Young, J M; Austin, J J; Weyrich, L S

2017-02-01

Analysis of physical evidence is typically a deciding factor in forensic casework by establishing what transpired at a scene or who was involved. Forensic geoscience is an emerging multi-disciplinary science that can offer significant benefits to forensic investigations. Soil is a powerful, nearly 'ideal' contact trace evidence, as it is highly individualistic, easy to characterise, has a high transfer and retention probability, and is often overlooked in attempts to conceal evidence. However, many real-life cases encounter close proximity soil samples or soils with low inorganic content, which cannot be easily discriminated based on current physical and chemical analysis techniques. The capability to improve forensic soil discrimination, and identify key indicator taxa from soil using the organic fraction is currently lacking. The development of new DNA sequencing technologies offers the ability to generate detailed genetic profiles from soils and enhance current forensic soil analyses. Here, we discuss the use of DNA metabarcoding combined with high-throughput sequencing (HTS) technology to distinguish between soils from different locations in a forensic context. Specifically, we provide recommendations for best practice, outline the potential limitations encountered in a forensic context and describe the future directions required to integrate soil DNA analysis into casework. © FEMS 2016. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Massively Parallel Sequencing of Forensic STRs Using the Ion Chef™ and the Ion S5™ XL Systems.

PubMed

Wang, Le; Chen, Man; Wu, Bo; Liu, Yi-Cheng; Zhang, Guang-Feng; Jiang, Li; Xu, Xiu-Lan; Zhao, Xing-Chun; Ji, An-Quan; Ye, Jian

2018-03-01

Next-generation sequencing (NGS) has been used to genotype forensic short tandem repeat (STR) markers for individual identification and kinship analysis. STR data from several NGS platforms have been published, but forensic application trials using the Ion S5™ XL system have not been reported. In this work, we report sensitivity, reproducibility, mixture, simulated degradation, and casework sample data on the Ion Chef™ and S5™ XL systems using an early access 25-plex panel. Sensitivity experiments showed that over 97% of the alleles were detectable with down to 62 pg input of genomic DNA. In mixture studies, alleles from minor contributors were correctly assigned at 1:9 and 9:1 ratios. NGS successfully gave 12 full genotype results from 13 challenging casework samples, compared with five full results using the CE platform. In conclusion, the Ion Chef™ and the Ion S5™ XL systems provided an alternative and promising approach for forensic STR genotyping. © 2018 American Academy of Forensic Sciences.

Automated processing of forensic casework samples using robotic workstations equipped with nondisposable tips: contamination prevention.

PubMed

Frégeau, Chantal J; Lett, C Marc; Elliott, Jim; Yensen, Craig; Fourney, Ron M

2008-05-01

An automated process has been developed for the analysis of forensic casework samples using TECAN Genesis RSP 150/8 or Freedom EVO liquid handling workstations equipped exclusively with nondisposable tips. Robot tip cleaning routines have been incorporated strategically within the DNA extraction process as well as at the end of each session. Alternative options were examined for cleaning the tips and different strategies were employed to verify cross-contamination. A 2% sodium hypochlorite wash (1/5th dilution of the 10.8% commercial bleach stock) proved to be the best overall approach for preventing cross-contamination of samples processed using our automated protocol. The bleach wash steps do not adversely impact the short tandem repeat (STR) profiles developed from DNA extracted robotically and allow for major cost savings through the implementation of fixed tips. We have demonstrated that robotic workstations equipped with fixed pipette tips can be used with confidence with properly designed tip washing routines to process casework samples using an adapted magnetic bead extraction protocol.

Interpretation guidelines of a standard Y-chromosome STR 17-plex PCR-CE assay for crime casework.

PubMed

Roewer, Lutz; Geppert, Maria

2012-01-01

Y-STR analysis is an invaluable tool to examine evidence in sexual assault cases and in other forensic casework. Unambiguous detection of the male component in DNA mixtures with a high female background is still the main field of application of forensic Y-STR haplotyping. In the last years, powerful technologies including a 17-locus multiplex PCR assay have been introduced in the forensic laboratories. At the same time, statistical methods have been developed and adapted for interpretation of a nonrecombining, linear marker as the Y-chromosome which shows a strongly clustered geographical distribution due to the linear inheritance and the patrilocality of ancestral groups. Large population databases, namely the Y-STR Haplotype Reference Database (YHRD), have been established to assess the evidentiary value of Y-STR matches by means of frequency estimation methods (counting and extrapolation).

Forensic validation of the SNPforID 52-plex assay.

PubMed

Musgrave-Brown, Esther; Ballard, David; Balogh, Kinga; Bender, Klaus; Berger, Burkhard; Bogus, Magdalena; Børsting, Claus; Brion, María; Fondevila, Manuel; Harrison, Cheryl; Oguzturun, Ceylan; Parson, Walther; Phillips, Chris; Proff, Carsten; Ramos-Luis, Eva; Sanchez, Juan J; Sánchez Diz, Paula; Sobrino Rey, Bea; Stradmann-Bellinghausen, Beate; Thacker, Catherine; Carracedo, Angel; Morling, Niels; Scheithauer, Richard; Schneider, Peter M; Syndercombe Court, Denise

2007-06-01

The advantages of single nucleotide polymorphism (SNP) typing in forensic genetics are well known and include a wider choice of high-throughput typing platforms, lower mutation rates, and improved analysis of degraded samples. However, if SNPs are to become a realistic supplement to current short tandem repeat (STR) typing methods, they must be shown to successfully and reliably analyse the challenging samples commonly encountered in casework situations. The European SNPforID consortium, supported by the EU GROWTH programme, has developed a multiplex of 52 SNPs for forensic analysis, with the amplification of all 52 loci in a single reaction followed by two single base extension (SBE) reactions which are detected with capillary electrophoresis. In order to validate this assay, a variety of DNA extracts were chosen to represent problems such as low copy number and degradation that are commonly seen in forensic casework. A total of 40 extracts were used in the study, each of which was sent to two of the five participating laboratories for typing in duplicate or triplicate. Laboratories were instructed to carry out their analyses as if they were dealing with normal casework samples. Results were reported back to the coordinating laboratory and compared with those obtained from traditional STR typing of the same extracts using Powerplex 16 (Promega). These results indicate that, although the ability to successfully type good quality, low copy number extracts is lower, the 52-plex SNP assay performed better than STR typing on degraded samples, and also on samples that were both degraded and of limited quantity, suggesting that SNP analysis can provide advantages over STR analysis in forensically relevant circumstances. However, there were also additional problems arising from contamination and primer quality issues and these are discussed.

DNA fingerprinting in forensics: past, present, future

PubMed Central

2013-01-01

DNA fingerprinting, one of the great discoveries of the late 20th century, has revolutionized forensic investigations. This review briefly recapitulates 30 years of progress in forensic DNA analysis which helps to convict criminals, exonerate the wrongly accused, and identify victims of crime, disasters, and war. Current standard methods based on short tandem repeats (STRs) as well as lineage markers (Y chromosome, mitochondrial DNA) are covered and applications are illustrated by casework examples. Benefits and risks of expanding forensic DNA databases are discussed and we ask what the future holds for forensic DNA fingerprinting. PMID:24245688

Developmental validation of the HIrisPlex system: DNA-based eye and hair colour prediction for forensic and anthropological usage.

PubMed

Walsh, Susan; Chaitanya, Lakshmi; Clarisse, Lindy; Wirken, Laura; Draus-Barini, Jolanta; Kovatsi, Leda; Maeda, Hitoshi; Ishikawa, Takaki; Sijen, Titia; de Knijff, Peter; Branicki, Wojciech; Liu, Fan; Kayser, Manfred

2014-03-01

Forensic DNA Phenotyping or 'DNA intelligence' tools are expected to aid police investigations and find unknown individuals by providing information on externally visible characteristics of unknown suspects, perpetrators and missing persons from biological samples. This is especially useful in cases where conventional DNA profiling or other means remain non-informative. Recently, we introduced the HIrisPlex system, capable of predicting both eye and hair colour from DNA. In the present developmental validation study, we demonstrate that the HIrisPlex assay performs in full agreement with the Scientific Working Group on DNA Analysis Methods (SWGDAM) guidelines providing an essential prerequisite for future HIrisPlex applications to forensic casework. The HIrisPlex assay produces complete profiles down to only 63 pg of DNA. Species testing revealed human specificity for a complete HIrisPlex profile, while only non-human primates showed the closest full profile at 20 out of the 24 DNA markers, in all animals tested. Rigorous testing of simulated forensic casework samples such as blood, semen, saliva stains, hairs with roots as well as extremely low quantity touch (trace) DNA samples, produced complete profiles in 88% of cases. Concordance testing performed between five independent forensic laboratories displayed consistent reproducible results on varying types of DNA samples. Due to its design, the assay caters for degraded samples, underlined here by results from artificially degraded DNA and from simulated casework samples of degraded DNA. This aspect was also demonstrated previously on DNA samples from human remains up to several hundreds of years old. With this paper, we also introduce enhanced eye and hair colour prediction models based on enlarged underlying databases of HIrisPlex genotypes and eye/hair colour phenotypes (eye colour: N = 9188 and hair colour: N = 1601). Furthermore, we present an online web-based system for individual eye and hair colour prediction from full and partial HIrisPlex DNA profiles. By demonstrating that the HIrisPlex assay is fully compatible with the SWGDAM guidelines, we provide the first forensically validated DNA test system for parallel eye and hair colour prediction now available to forensic laboratories for immediate casework application, including missing person cases. Given the robustness and sensitivity described here and in previous work, the HIrisPlex system is also suitable for analysing old and ancient DNA in anthropological and evolutionary studies. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

PopAffiliator: online calculator for individual affiliation to a major population group based on 17 autosomal short tandem repeat genotype profile.

PubMed

Pereira, Luísa; Alshamali, Farida; Andreassen, Rune; Ballard, Ruth; Chantratita, Wasun; Cho, Nam Soo; Coudray, Clotilde; Dugoujon, Jean-Michel; Espinoza, Marta; González-Andrade, Fabricio; Hadi, Sibte; Immel, Uta-Dorothee; Marian, Catalin; Gonzalez-Martin, Antonio; Mertens, Gerhard; Parson, Walther; Perone, Carlos; Prieto, Lourdes; Takeshita, Haruo; Rangel Villalobos, Héctor; Zeng, Zhaoshu; Zhivotovsky, Lev; Camacho, Rui; Fonseca, Nuno A

2011-09-01

Because of their sensitivity and high level of discrimination, short tandem repeat (STR) maker systems are currently the method of choice in routine forensic casework and data banking, usually in multiplexes up to 15-17 loci. Constraints related to sample amount and quality, frequently encountered in forensic casework, will not allow to change this picture in the near future, notwithstanding the technological developments. In this study, we present a free online calculator named PopAffiliator ( http://cracs.fc.up.pt/popaffiliator ) for individual population affiliation in the three main population groups, Eurasian, East Asian and sub-Saharan African, based on genotype profiles for the common set of STRs used in forensics. This calculator performs affiliation based on a model constructed using machine learning techniques. The model was constructed using a data set of approximately fifteen thousand individuals collected for this work. The accuracy of individual population affiliation is approximately 86%, showing that the common set of STRs routinely used in forensics provide a considerable amount of information for population assignment, in addition to being excellent for individual identification.

Forensic individual age estimation with DNA: From initial approaches to methylation tests.

PubMed

Freire-Aradas, A; Phillips, C; Lareu, M V

2017-07-01

Individual age estimation is a key factor in forensic science analysis that can provide very useful information applicable to criminal, legal, and anthropological investigations. Forensic age inference was initially based on morphological inspection or radiography and only later began to adopt molecular approaches. However, a lack of accuracy or technical problems hampered the introduction of these DNA-based methodologies in casework analysis. A turning point occurred when the epigenetic signature of DNA methylation was observed to gradually change during an individual´s lifespan. In the last four years, the number of publications reporting DNA methylation age-correlated changes has gradually risen and the forensic community now has a range of age methylation tests applicable to forensic casework. Most forensic age predictor models have been developed based on blood DNA samples, but additional tissues are now also being explored. This review assesses the most widely adopted genes harboring methylation sites, detection technologies, statistical age-predictive analyses, and potential causes of variation in age estimates. Despite the need for further work to improve predictive accuracy and establishing a broader range of tissues for which tests can analyze the most appropriate methylation sites, several forensic age predictors have now been reported that provide consistency in their prediction accuracies (predictive error of ±4 years); this makes them compelling tools with the potential to contribute key information to help guide criminal investigations. Copyright © 2017 Central Police University.

Calculating the weight of evidence in low-template forensic DNA casework.

PubMed

Lohmueller, Kirk E; Rudin, Norah

2013-01-01

Interpreting and assessing the weight of low-template DNA evidence presents a formidable challenge in forensic casework. This report describes a case in which a similar mixed DNA profile was obtained from four different bloodstains. The defense proposed that the low-level minor profile came from an alternate suspect, the defendant's mistress. The strength of the evidence was assessed using a probabilistic approach that employed likelihood ratios incorporating the probability of allelic drop-out. Logistic regression was used to model the probability of drop-out using empirical validation data from the government laboratory. The DNA profile obtained from the bloodstain described in this report is at least 47 billion times more likely if, in addition to the victim, the alternate suspect was the minor contributor, than if another unrelated individual was the minor contributor. This case illustrates the utility of the probabilistic approach for interpreting complex low-template DNA profiles. © 2012 American Academy of Forensic Sciences.

New incompatibilities uncovered using the Promega DNA IQ™ chemistry.

PubMed

Laurin, Nancy; Célestin, Florence; Clark, Meagan; Wilkinson, Della; Yamashita, Brian; Frégeau, Chantal

2015-12-01

Over the years, the Promega DNA IQ™ System was proven an effective technology for the production of clean DNA from a wide variety of casework specimens. The capture of DNA using the DNA IQ™ paramagnetic beads, however, was shown to be affected by a few specific chemicals that could be present on exhibits submitted to the laboratory. In this study, various blood and latent fingerprint enhancement reagents/methods, marker pens and adhesive tapes, applied at the crime scene or in the forensic laboratory on casework exhibits or used to collect biological material, were tested for their compatibility with the DNA IQ™ technology. Although no impact on DNA recovery was observed for most reagents, the MAGNA™ Jet Black fingerprint powder and three 3M Scotch(®) adhesive tapes were shown to severely or completely inhibit DNA binding onto the DNA IQ™ beads. The effect of MAGNA™ Jet Black on DNA recovery could be counteracted by separating the magnetic powder from the lysates by centrifugation or filtration, prior to DNA extraction. High quality STR profiles were obtained from samples subjected to MAGNA™ Jet Black suggesting it does not impact DNA integrity. Crown Copyright © 2015. Published by Elsevier Ireland Ltd. All rights reserved.

Comparing Species Composition of Passive Trapping of Adult Flies with Larval Collections from the Body during Scene-Based Medicolegal Death Investigations

PubMed Central

Sanford, Michelle R.

2017-01-01

Collection of insects at the scene is one of the most important aspects of forensic entomology and proper collection is one of the biggest challenges for any investigator. Adult flies are highly mobile and ubiquitous at scenes, yet their link to the body and the time of colonization (TOC) and post-mortem interval (PMI) estimates is not well established. Collection of adults is widely recommended for casework but has yet to be rigorously evaluated during medicolegal death investigations for its value to the investigation. In this study, sticky card traps and immature collections were compared for 22 cases investigated by the Harris County Institute of Forensic Sciences, Houston, TX, USA. Cases included all manner of death classifications and a range of decomposition stages from indoor and outdoor scenes. Overall, the two methods successfully collected at least one species in common only 65% of the time, with at least one species unique to one of the methods 95% of the time. These results suggest that rearing of immature specimens collected from the body should be emphasized during training to ensure specimens directly associated with the colonization of the body can be identified using adult stages if necessary. PMID:28338605

Validation of LC–TOF-MS Screening for Drugs, Metabolites, and Collateral Compounds in Forensic Toxicology Specimens

PubMed Central

Guale, Fessessework; Shahreza, Shahriar; Walterscheid, Jeffrey P.; Chen, Hsin-Hung; Arndt, Crystal; Kelly, Anna T.; Mozayani, Ashraf

2013-01-01

Liquid chromatography time-of-flight mass spectrometry (LC–TOF-MS) analysis provides an expansive technique for identifying many known and unknown analytes. This study developed a screening method that utilizes automated solid-phase extraction to purify a wide array of analytes involving stimulants, benzodiazepines, opiates, muscle relaxants, hypnotics, antihistamines, antidepressants and newer synthetic “Spice/K2” cannabinoids and cathinone “bath salt” designer drugs. The extract was applied to LC–TOF-MS analysis, implementing a 13 min chromatography gradient with mobile phases of ammonium formate and methanol using positive mode electrospray. Several common drugs and metabolites can share the same mass and chemical formula among unrelated compounds, but they are structurally different. In this method, the LC–TOF-MS was able to resolve many isobaric compounds by accurate mass correlation within 15 ppm mass units and a narrow retention time interval of less than 10 s of separation. Drug recovery yields varied among spiked compounds, but resulted in overall robust area counts to deliver an average match score of 86 when compared to the retention time and mass of authentic standards. In summary, this method represents a rapid, enhanced screen for blood and urine specimens in postmortem, driving under the influence, and drug facilitated sexual assault forensic toxicology casework. PMID:23118149

Validation of LC-TOF-MS screening for drugs, metabolites, and collateral compounds in forensic toxicology specimens.

PubMed

Guale, Fessessework; Shahreza, Shahriar; Walterscheid, Jeffrey P; Chen, Hsin-Hung; Arndt, Crystal; Kelly, Anna T; Mozayani, Ashraf

2013-01-01

Liquid chromatography time-of-flight mass spectrometry (LC-TOF-MS) analysis provides an expansive technique for identifying many known and unknown analytes. This study developed a screening method that utilizes automated solid-phase extraction to purify a wide array of analytes involving stimulants, benzodiazepines, opiates, muscle relaxants, hypnotics, antihistamines, antidepressants and newer synthetic "Spice/K2" cannabinoids and cathinone "bath salt" designer drugs. The extract was applied to LC-TOF-MS analysis, implementing a 13 min chromatography gradient with mobile phases of ammonium formate and methanol using positive mode electrospray. Several common drugs and metabolites can share the same mass and chemical formula among unrelated compounds, but they are structurally different. In this method, the LC-TOF-MS was able to resolve many isobaric compounds by accurate mass correlation within 15 ppm mass units and a narrow retention time interval of less than 10 s of separation. Drug recovery yields varied among spiked compounds, but resulted in overall robust area counts to deliver an average match score of 86 when compared to the retention time and mass of authentic standards. In summary, this method represents a rapid, enhanced screen for blood and urine specimens in postmortem, driving under the influence, and drug facilitated sexual assault forensic toxicology casework.

Microchip-based cell lysis and DNA extraction from sperm cells for application to forensic analysis.

PubMed

Bienvenue, Joan M; Duncalf, Natalie; Marchiarullo, Daniel; Ferrance, Jerome P; Landers, James P

2006-03-01

The current backlog of casework is among the most significant challenges facing crime laboratories at this time. While the development of next-generation microchip-based technology for expedited forensic casework analysis offers one solution to this problem, this will require the adaptation of manual, large-volume, benchtop chemistry to small volume microfluidic devices. Analysis of evidentiary materials from rape kits where semen or sperm cells are commonly found represents a unique set of challenges for on-chip cell lysis and DNA extraction that must be addressed for successful application. The work presented here details the development of a microdevice capable of DNA extraction directly from sperm cells for application to the analysis of sexual assault evidence. A variety of chemical lysing agents are assessed for inclusion in the extraction protocol and a method for DNA purification from sperm cells is described. Suitability of the extracted DNA for short tandem repeat (STR) analysis is assessed and genetic profiles shown. Finally, on-chip cell lysis methods are evaluated, with results from fluorescence visualization of cell rupture and DNA extraction from an integrated cell lysis and purification with subsequent STR amplification presented. A method for on-chip cell lysis and DNA purification is described, with considerations toward inclusion in an integrated microdevice capable of both differential cell sorting and DNA extraction. The results of this work demonstrate the feasibility of incorporating microchip-based cell lysis and DNA extraction into forensic casework analysis.

Application of the BioMek 2000 Laboratory Automation Workstation and the DNA IQ System to the extraction of forensic casework samples.

PubMed

Greenspoon, Susan A; Ban, Jeffrey D; Sykes, Karen; Ballard, Elizabeth J; Edler, Shelley S; Baisden, Melissa; Covington, Brian L

2004-01-01

Robotic systems are commonly utilized for the extraction of database samples. However, the application of robotic extraction to forensic casework samples is a more daunting task. Such a system must be versatile enough to accommodate a wide range of samples that may contain greatly varying amounts of DNA, but it must also pose no more risk of contamination than the manual DNA extraction methods. This study demonstrates that the BioMek 2000 Laboratory Automation Workstation, used in combination with the DNA IQ System, is versatile enough to accommodate the wide range of samples typically encountered by a crime laboratory. The use of a silica coated paramagnetic resin, as with the DNA IQ System, facilitates the adaptation of an open well, hands off, robotic system to the extraction of casework samples since no filtration or centrifugation steps are needed. Moreover, the DNA remains tightly coupled to the silica coated paramagnetic resin for the entire process until the elution step. A short pre-extraction incubation step is necessary prior to loading samples onto the robot and it is at this step that most modifications are made to accommodate the different sample types and substrates commonly encountered with forensic evidentiary samples. Sexual assault (mixed stain) samples, cigarette butts, blood stains, buccal swabs, and various tissue samples were successfully extracted with the BioMek 2000 Laboratory Automation Workstation and the DNA IQ System, with no evidence of contamination throughout the extensive validation studies reported here.

On the Contribution of Raman Spectroscopy to Forensic Science

NASA Astrophysics Data System (ADS)

Buzzini, Patrick; Massonnet, Genevieve

2010-08-01

Raman spectroscopy has only recently sparked interest from forensic laboratories. The Raman technique has demonstrated important advantages such as its nondestructive nature, its fast analysis time, and especially the possibility of performing microscopical in situ analyses. In forensic applications, it is a versatile technique that covers a wide spectrum of substances such as trace evidence, illicit drugs and inks. An overview of the recent developments of Raman spectroscopy in forensic science will be discussed. Also, the requirements for an analytical technique for the examination of physical evidence will be described. Examples of casework will be depicted.

A review of sex estimation techniques during examination of skeletal remains in forensic anthropology casework.

PubMed

Krishan, Kewal; Chatterjee, Preetika M; Kanchan, Tanuj; Kaur, Sandeep; Baryah, Neha; Singh, R K

2016-04-01

Sex estimation is considered as one of the essential parameters in forensic anthropology casework, and requires foremost consideration in the examination of skeletal remains. Forensic anthropologists frequently employ morphologic and metric methods for sex estimation of human remains. These methods are still very imperative in identification process in spite of the advent and accomplishment of molecular techniques. A constant boost in the use of imaging techniques in forensic anthropology research has facilitated to derive as well as revise the available population data. These methods however, are less reliable owing to high variance and indistinct landmark details. The present review discusses the reliability and reproducibility of various analytical approaches; morphological, metric, molecular and radiographic methods in sex estimation of skeletal remains. Numerous studies have shown a higher reliability and reproducibility of measurements taken directly on the bones and hence, such direct methods of sex estimation are considered to be more reliable than the other methods. Geometric morphometric (GM) method and Diagnose Sexuelle Probabiliste (DSP) method are emerging as valid methods and widely used techniques in forensic anthropology in terms of accuracy and reliability. Besides, the newer 3D methods are shown to exhibit specific sexual dimorphism patterns not readily revealed by traditional methods. Development of newer and better methodologies for sex estimation as well as re-evaluation of the existing ones will continue in the endeavour of forensic researchers for more accurate results. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Development and validation of a D-loop mtDNA SNP assay for the screening of specimens in forensic casework.

PubMed

Chemale, Gustavo; Paneto, Greiciane Gaburro; Menezes, Meiga Aurea Mendes; de Freitas, Jorge Marcelo; Jacques, Guilherme Silveira; Cicarelli, Regina Maria Barretto; Fagundes, Paulo Roberto

2013-05-01

Mitochondrial DNA (mtDNA) analysis is usually a last resort in routine forensic DNA casework. However, it has become a powerful tool for the analysis of highly degraded samples or samples containing too little or no nuclear DNA, such as old bones and hair shafts. The gold standard methodology still constitutes the direct sequencing of polymerase chain reaction (PCR) products or cloned amplicons from the HVS-1 and HVS-2 (hypervariable segment) control region segments. Identifications using mtDNA are time consuming, expensive and can be very complex, depending on the amount and nature of the material being tested. The main goal of this work is to develop a less labour-intensive and less expensive screening method for mtDNA analysis, in order to aid in the exclusion of non-matching samples and as a presumptive test prior to final confirmatory DNA sequencing. We have selected 14 highly discriminatory single nucleotide polymorphisms (SNPs) based on simulations performed by Salas and Amigo (2010) to be typed using SNaPShot(TM) (Applied Biosystems, Foster City, CA, USA). The assay was validated by typing more than 100 HVS-1/HVS-2 sequenced samples. No differences were observed between the SNP typing and DNA sequencing when results were compared, with the exception of allelic dropouts observed in a few haplotypes. Haplotype diversity simulations were performed using 172 mtDNA sequences representative of the Brazilian population and a score of 0.9794 was obtained when the 14 SNPs were used, showing that the theoretical prediction approach for the selection of highly discriminatory SNPs suggested by Salas and Amigo (2010) was confirmed in the population studied. As the main goal of the work is to develop a screening assay to skip the sequencing of all samples in a particular case, a pair-wise comparison of the sequences was done using the selected SNPs. When both HVS-1/HVS-2 SNPs were used for simulations, at least two differences were observed in 93.2% of the comparisons performed. The assay was validated with casework samples. Results show that the method is straightforward and can be used for exclusionary purposes, saving time and laboratory resources. The assay confirms the theoretic prediction suggested by Salas and Amigo (2010). All forensic advantages, such as high sensitivity and power of discrimination, as also the disadvantages, such as the occurrence of allele dropouts, are discussed throughout the article. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

An optimized procedure for obtaining DNA from fired and unfired ammunition.

PubMed

Montpetit, Shawn; O'Donnell, Patrick

2015-07-01

Gun crimes are a significant problem facing law enforcement agencies. Traditional forensic examination of firearms involves comparisons of markings imparted to bullets and cartridge casings during the firing process. DNA testing of casings and cartridges may not be routinely done in crime laboratories due a variety of factors including the typically low amounts of DNA recovered. The San Diego Police Department (SDPD) Crime Laboratory conducted a study to optimize the collection and profiling of DNA from fired and unfired ammunition. The method was optimized to where interpretable DNA results were obtained for 26.1% of the total number of forensic casework evidence samples, and provided some insights into the level of secondary transfer that might be expected from this type of evidence. Briefly detailed are the results from the experimental study and the forensic casework analysis using the optimized process. Mixtures (samples having more DNA types than the loader's known genotype detected or visible at any marker) were obtained in 39.8% of research samples and the likely source of DNA mixtures is discussed. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Guilty by dissociation-development of gas chromatography-mass spectrometry (GC-MS) and other rapid screening methods for the analysis of 13 diphenidine-derived new psychoactive substances (NPSs).

PubMed

Geyer, Pierre M; Hulme, Matthew C; Irving, Joseph P B; Thompson, Paul D; Ashton, Ryan N; Lee, Robert J; Johnson, Lucy; Marron, Jack; Banks, Craig E; Sutcliffe, Oliver B

2016-11-01

The prevalence of new psychoactive substances (NPSs) in forensic casework has increased prominently in recent years. This has given rise to significant legal and analytical challenges in the identification of these substances. The requirement for validated, robust and rapid testing methodologies for these compounds is obvious. This study details the analysis of 13 synthesised diphenidine derivatives encountered in casework using presumptive testing, thin layer chromatography and gas chromatography-mass spectrometry (GC-MS). Specifically, the validated GC-MS method provides, for the first time, both a general screening method and quantification of the active components for seized solid samples, both in their pure form and in the presence of common adulterants. Graphical Abstract Chemical synthesis and forensic analysis of 13 diphenidine-derived new psychoactive substance(s).

Whole genome nucleosome sequencing identifies novel types of forensic markers in degraded DNA samples

PubMed Central

Dong, Chun-nan; Yang, Ya-dong; Li, Shu-jin; Yang, Ya-ran; Zhang, Xiao-jing; Fang, Xiang-dong; Yan, Jiang-wei; Cong, Bin

2016-01-01

In the case of mass disasters, missing persons and forensic caseworks, highly degraded biological samples are often encountered. It can be a challenge to analyze and interpret the DNA profiles from these samples. Here we provide a new strategy to solve the problem by taking advantage of the intrinsic structural properties of DNA. We have assessed the in vivo positions of more than 35 million putative nucleosome cores in human leukocytes using high-throughput whole genome sequencing, and identified 2,462 single nucleotide variations (SNVs), 128 insertion-deletion polymorphisms (indels). After comparing the sequence reads with 44 STR loci commonly used in forensics, five STRs (TH01, TPOX, D18S51, DYS391, and D10S1248)were matched. We compared these “nucleosome protected STRs” (NPSTRs) with five other non-NPSTRs using mini-STR primer design, real-time PCR, and capillary gel electrophoresis on artificially degraded DNA. Moreover, genotyping performance of the five NPSTRs and five non-NPSTRs was also tested with real casework samples. All results show that loci located in nucleosomes are more likely to be successfully genotyped in degraded samples. In conclusion, after further strict validation, these markers could be incorporated into future forensic and paleontology identification kits, resulting in higher discriminatory power for certain degraded sample types. PMID:27189082

Assessment of the role of DNA repair in damaged forensic samples.

PubMed

Ambers, Angie; Turnbough, Meredith; Benjamin, Robert; King, Jonathan; Budowle, Bruce

2014-11-01

Previous studies on DNA damage and repair have involved in vitro laboratory procedures that induce a single type of lesion in naked templates. Although repair of singular, sequestered types of DNA damage has shown some success, forensic and ancient specimens likely contain a number of different types of lesions. This study sought to (1) develop protocols to damage DNA in its native state, (2) generate a pool of candidate samples for repair that more likely emulate authentic forensic samples, and (3) assess the ability of the PreCR(TM) Repair Mix to repair the resultant lesions. Complexed, native DNA is more difficult to damage than naked DNA. Modified procedures included the use of higher concentrations and longer exposure times. Three types of samples, those that demonstrated damage based on short tandem repeat (STR) profile signals, were selected for repair experiments: environmentally damaged bloodstains, bleach-damaged whole blood, and human skeletal remains. Results showed trends of improved performance of STR profiling of bleach-damaged DNA. However, the repair assay did not improve DNA profiles from environmentally damaged bloodstains or bone, and in some cases resulted in lower RFU values for STR alleles. The extensive spectrum of DNA damage and myriad combinations of lesions that can be present in forensic samples appears to pose a challenge for the in vitro PreCR(TM) assay. The data suggest that the use of PreCR in casework should be considered with caution due to the assay's varied results.

A high-throughput Sanger strategy for human mitochondrial genome sequencing

PubMed Central

2013-01-01

Background A population reference database of complete human mitochondrial genome (mtGenome) sequences is needed to enable the use of mitochondrial DNA (mtDNA) coding region data in forensic casework applications. However, the development of entire mtGenome haplotypes to forensic data quality standards is difficult and laborious. A Sanger-based amplification and sequencing strategy that is designed for automated processing, yet routinely produces high quality sequences, is needed to facilitate high-volume production of these mtGenome data sets. Results We developed a robust 8-amplicon Sanger sequencing strategy that regularly produces complete, forensic-quality mtGenome haplotypes in the first pass of data generation. The protocol works equally well on samples representing diverse mtDNA haplogroups and DNA input quantities ranging from 50 pg to 1 ng, and can be applied to specimens of varying DNA quality. The complete workflow was specifically designed for implementation on robotic instrumentation, which increases throughput and reduces both the opportunities for error inherent to manual processing and the cost of generating full mtGenome sequences. Conclusions The described strategy will assist efforts to generate complete mtGenome haplotypes which meet the highest data quality expectations for forensic genetic and other applications. Additionally, high-quality data produced using this protocol can be used to assess mtDNA data developed using newer technologies and chemistries. Further, the amplification strategy can be used to enrich for mtDNA as a first step in sample preparation for targeted next-generation sequencing. PMID:24341507

Critical issues in the historical and contemporary development of forensic anthropology in Australia: An international comparison.

PubMed

Mallett, Xanthé; Evison, Martin P

2017-06-01

The aim of this brief critical qualitative analysis is to examine the development of forensic anthropology in Australia, at a time of significant change in the discipline. It will briefly summarise its historical establishment, making comparative reference to other regions-particularly the United Kingdom and United States, and the influence of the Bali Bombings of 2002, Indian Ocean earthquake and tsunami of 2004 and Black Saturday Bushfires of 2009. The analysis goes on to consider key factors in research in forensic anthropology in the United States, and the development of standards and regulation in the US and UK. The significance of research in post-mortem diagenesis in Brazil-a country sharing aspects of climate, soil types and demography with Australia-is also considered, as well as the significance of patterns of casework encountered in Australia compared with those of other jurisdictions. While forensic anthropology as a discipline has grown remarkably in recent years, this analysis suggests that research and training tailored to the specific pattern of casework encountered in Australia is now essential to support the development of national standards in science, education, and professional regulation. The significance of the establishment of the first taphonomy research facility outside of the US-the Australian Facility for Taphonomic Experimental Research-is briefly considered with reference to what this facility may offer to the development of forensic anthropology in Australia. Copyright © 2017 Elsevier B.V. All rights reserved.

Forensic differentiation between peripheral and menstrual blood in cases of alleged sexual assault-validating an immunochromatographic multiplex assay for simultaneous detection of human hemoglobin and D-dimer.

PubMed

Holtkötter, Hannah; Dias Filho, Claudemir Rodrigues; Schwender, Kristina; Stadler, Christian; Vennemann, Marielle; Pacheco, Ana Claudia; Roca, Gabriela

2018-05-01

Sexual assault is a serious offense and identification of body fluids originating from sexual activity has been a crucial aspect of forensic investigations for a long time. While reliable tests for the detection of semen and saliva have been successfully implemented into forensic laboratories, the detection of other body fluids, such as vaginal or menstrual fluid, is more challenging. Especially, the discrimination between peripheral and menstrual blood can be highly relevant for police investigations because it provides potential evidence regarding the issue of consent. We report the forensic validation of an immunochromatographic test that allows for such discrimination in forensic stains, the SERATEC PMB test, and its performance on real casework samples. The PMB test is a duplex test combining human hemoglobin and D-dimer detection and was developed for the identification of blood and menstrual fluid, both at the crime scene and in the laboratory. The results of this study showed that the duplex D-dimer/hemoglobin assay reliably detects the presence of human hemoglobin and identifies samples containing menstrual fluid by detecting the presence of D-dimers. The method distinguished between menstrual and peripheral blood in a swab from a historical artifact and in real casework samples of alleged sexual assaults. Results show that the development of the new duplex test is a substantial progress towards analyzing and interpreting evidence from sexual assault cases.

The forensic anthropology legacy of T. Dale Stewart (1901-1997).

PubMed

Ubelaker, D H

2000-03-01

T. Dale Stewart (1901-1997) began his Smithsonian career as a temporary aide to Ales Hrdlicka (1869-1943) in 1924. At the time of his death in 1997, he was regarded world-wide as an authority who led the professional development of American forensic anthropology. He was a prodigious researcher, best known for his meticulous attention to detail, balanced scientific judgment, keen sense of research design, and ability for synthesis. Stewart's publications, extensive casework for the FBI and others, his court testimony, publications, professional contacts, and organizational activity merit him a prominent place in the history of American forensic anthropology.

Mitochondrial DNA heteroplasmy in the emerging field of massively parallel sequencing

PubMed Central

Just, Rebecca S.; Irwin, Jodi A.; Parson, Walther

2015-01-01

Long an important and useful tool in forensic genetic investigations, mitochondrial DNA (mtDNA) typing continues to mature. Research in the last few years has demonstrated both that data from the entire molecule will have practical benefits in forensic DNA casework, and that massively parallel sequencing (MPS) methods will make full mitochondrial genome (mtGenome) sequencing of forensic specimens feasible and cost-effective. A spate of recent studies has employed these new technologies to assess intraindividual mtDNA variation. However, in several instances, contamination and other sources of mixed mtDNA data have been erroneously identified as heteroplasmy. Well vetted mtGenome datasets based on both Sanger and MPS sequences have found authentic point heteroplasmy in approximately 25% of individuals when minor component detection thresholds are in the range of 10–20%, along with positional distribution patterns in the coding region that differ from patterns of point heteroplasmy in the well-studied control region. A few recent studies that examined very low-level heteroplasmy are concordant with these observations when the data are examined at a common level of resolution. In this review we provide an overview of considerations related to the use of MPS technologies to detect mtDNA heteroplasmy. In addition, we examine published reports on point heteroplasmy to characterize features of the data that will assist in the evaluation of future mtGenome data developed by any typing method. PMID:26009256

Forensic genetic analyses in isolated populations with examples of central European Valachs and Roma.

PubMed

Ehler, Edvard; Vanek, Daniel

2017-05-01

Isolated populations present a constant threat to the correctness of forensic genetic casework. In this review article we present several examples of how analyzing samples from isolated populations can bias the results of the forensic statistics and analyses. We select our examples from isolated populations from central and southeastern Europe, namely the Valachs and the European Roma. We also provide the reader with general strategies and principles to improve the laboratory practice (best practice) and reporting of samples from supposedly isolated populations. These include reporting the precise population data used for computing the forensic statistics, using the appropriate θ correction factor for calculating allele frequencies, typing ancestry informative markers in samples of unknown or uncertain ethnicity and establishing ethnic-specific forensic databases. Copyright © 2017 Elsevier Ltd and Faculty of Forensic and Legal Medicine. All rights reserved.

Accuracy Rates of Ancestry Estimation by Forensic Anthropologists Using Identified Forensic Cases.

PubMed

Thomas, Richard M; Parks, Connie L; Richard, Adam H

2017-07-01

A common task in forensic anthropology involves the estimation of the ancestry of a decedent by comparing their skeletal morphology and measurements to skeletons of individuals from known geographic groups. However, the accuracy rates of ancestry estimation methods in actual forensic casework have rarely been studied. This article uses 99 forensic cases with identified skeletal remains to develop accuracy rates for ancestry estimations conducted by forensic anthropologists. The overall rate of correct ancestry estimation from these cases is 90.9%, which is comparable to most research-derived rates and those reported by individual practitioners. Statistical tests showed no significant difference in accuracy rates depending on examiner education level or on the estimated or identified ancestry. More recent cases showed a significantly higher accuracy rate. The incorporation of metric analyses into the ancestry estimate in these cases led to a higher accuracy rate. © 2017 American Academy of Forensic Sciences.

Y chromosome STR typing in crime casework.

PubMed

Roewer, Lutz

2009-01-01

Since the beginning of the nineties the field of forensic Y chromosome analysis has been successfully developed to become commonplace in laboratories working in crime casework all over the world. The ability to identify male-specific DNA renders highly variable Y-chromosomal polymorphisms, the STR sequences, an invaluable addition to the standard panel of autosomal loci used in forensic genetics. The male-specificity makes the Y chromosome especially useful in cases of male/female cell admixture, namely in sexual assault cases. On the other hand, the haploidy and patrilineal inheritance complicates the interpretation of a Y-STR match, because male relatives share for several generations an identical Y-STR profile. Since paternal relatives tend to live in the geographic and cultural territory of their ancestors, the Y chromosome analysis has a potential to make inferences on the population of origin of a given DNA profile. This review addresses the fields of application of Y chromosome haplotyping, the interpretation of results, databasing efforts and population genetics aspects.

Analysis of 17 STR data on 5362 southern Portuguese individuals-an update on reference database.

PubMed

Cabezas Silva, Raquel; Ribeiro, Teresa; Lucas, Isabel; Porto, Maria João; Costa Santos, Jorge; Dario, Paulo

2016-03-01

The main objective of this work consisted of the updating of allele frequencies and other relevant forensic parameters for the 17 autosomal STR loci provided by the combination of the two types of kits used routinely in our laboratory casework: AmpF/STR Identifiler(®) and the Powerplex(®) 16 Systems. This aim was of significant importance, given that the last study on these kits within the southern Portuguese population dates back to 2006, and, as a consequence, it was necessary to correct the deviation caused by population evolution over the last ten years so that they might be better applied to our forensic casework. For this reason genetic data from 5362 unrelated Caucasian Portuguese individuals from the south of Portugal who were involved in paternity testing casework from 2005 to 2014 was used. Of all the markers, TPOX proved to be the least polymorphic, and Penta E the most. Secondly, this up-to-date southern Portuguese population was compared not only with the northern and central Portuguese populations, but also with that of southern Portugal in 2006, along with populations from Spain, Italy, Greece, Romania, Morocco, Angola and Korea in order to infer information about the relatedness of these respective populations, and the variation of the southern Portuguese population over time. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Application of Ion Mobility Spectrometry (IMS) in forensic chemistry and toxicology with focus on biological matrices

NASA Technical Reports Server (NTRS)

Bernhard, Werner; Keller, Thomas; Regenscheit, Priska

1995-01-01

The IMS (Ion Mobility Spectroscopy) instrument 'Ionscan' takes advantage of the fact that trace quantities of illicit drugs are adsorbed on dust particles on clothes, in cars and on other items of evidence. The dust particles are collected on a membrane filter by a special attachment on a vacuum cleaner. The sample is then directly inserted into the spectrometer and can be analyzed immediately. We show casework applications of a forensic chemistry and toxicology laboratory. One new application of IMS in forensic chemistry is the detection of psilocybin in dried mushrooms without any further sample preparation.

New psychoactive substances: catalysing a shift in forensic science practice?

PubMed

Tettey, Justice; Crean, Conor

2015-08-05

The analysis of substances of abuse remains one of the most matured areas in forensic science with a strong scientific basis, namely analytical chemistry. The current evolving drug markets, characterized by the global emergence of new psychoactive substances (NPS) and the need for forensic scientists to identify an unprecedented and ever-increasing number of NPS, presents a unique challenge to this discipline. This article looks at the current situation with NPS at the global level, and the challenges posed to the otherwise technically robust forensic science discipline of analysis of substances of abuse. It discusses the preparedness of forensic science to deal with the current situation and identifies the need for a shift in forensic science practice, especially one which embraces research and looks beyond normal casework in order to provide the much needed data for developing effective policy responses to the NPS problem. © 2015 The Author(s) Published by the Royal Society. All rights reserved.

A novel real time PCR assay using melt curve analysis for ivory identification.

PubMed

Kitpipit, Thitika; Penchart, Kitichaya; Ouithavon, Kanita; Satasook, Chutamas; Linacre, Adrian; Thanakiatkrai, Phuvadol

2016-10-01

Demand for ivory and expansion of human settlements have resulted in a rapid decline in the number of elephants. Enforcement of local and international laws and regulations requires identification of the species from which any ivory, or ivory products, originated. Further geographical assignment of the dead elephant from which the ivory was taken can assist in forensic investigations. In this study, a real-time PCR assay using melt curve analysis was developed and fully validated for forensic use. The presence or absence of three Elephantidae-specific and elephant species-specific melting peaks was used to identify the elephant species. Using 141 blood and ivory samples from the three extant elephant species, the assay demonstrated very high reproducibility and accuracy. The limit of detection was as low as 0.031ng of input DNA for conventional amplification and 0.002ng for nested amplification. Both DNA concentrations are typically encountered in forensic casework, especially for degraded samples. No cross-reactivity was observed for non-target species. Evaluation of direct amplification and nested amplification demonstrated the assay's flexibility and capability of analyzing low-template DNA samples and aged samples. Additionally, blind trial testing showed the assay's suitability application in real casework. In conclusion, wildlife forensic laboratories could use this novel, quick, and low-cost assay to help combat the continuing poaching crises leading to the collapse of elephant numbers in the wild. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Infrared imaging of the crime scene: possibilities and pitfalls.

PubMed

Edelman, Gerda J; Hoveling, Richelle J M; Roos, Martin; van Leeuwen, Ton G; Aalders, Maurice C G

2013-09-01

All objects radiate infrared energy invisible to the human eye, which can be imaged by infrared cameras, visualizing differences in temperature and/or emissivity of objects. Infrared imaging is an emerging technique for forensic investigators. The rapid, nondestructive, and noncontact features of infrared imaging indicate its suitability for many forensic applications, ranging from the estimation of time of death to the detection of blood stains on dark backgrounds. This paper provides an overview of the principles and instrumentation involved in infrared imaging. Difficulties concerning the image interpretation due to different radiation sources and different emissivity values within a scene are addressed. Finally, reported forensic applications are reviewed and supported by practical illustrations. When introduced in forensic casework, infrared imaging can help investigators to detect, to visualize, and to identify useful evidence nondestructively. © 2013 American Academy of Forensic Sciences.

Nuclear Forensic Science: Analysis of Nuclear Material Out of Regulatory Control

NASA Astrophysics Data System (ADS)

Kristo, Michael J.; Gaffney, Amy M.; Marks, Naomi; Knight, Kim; Cassata, William S.; Hutcheon, Ian D.

2016-06-01

Nuclear forensic science seeks to identify the origin of nuclear materials found outside regulatory control. It is increasingly recognized as an integral part of a robust nuclear security program. This review highlights areas of active, evolving research in nuclear forensics, with a focus on analytical techniques commonly employed in Earth and planetary sciences. Applications of nuclear forensics to uranium ore concentrates (UOCs) are discussed first. UOCs have become an attractive target for nuclear forensic researchers because of the richness in impurities compared to materials produced later in the fuel cycle. The development of chronometric methods for age dating nuclear materials is then discussed, with an emphasis on improvements in accuracy that have been gained from measurements of multiple radioisotopic systems. Finally, papers that report on casework are reviewed, to provide a window into current scientific practice.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kristo, Michael J.; Gaffney, Amy M.; Marks, Naomi

Nuclear forensic science seeks to identify the origin of nuclear materials found outside regulatory control. It is increasingly recognized as an integral part of a robust nuclear security program. Our review highlights areas of active, evolving research in nuclear forensics, with a focus on analytical techniques commonly employed in Earth and planetary sciences. Applications of nuclear forensics to uranium ore concentrates (UOCs) are discussed first. UOCs have become an attractive target for nuclear forensic researchers because of the richness in impurities compared to materials produced later in the fuel cycle. Furthermore, the development of chronometric methods for age dating nuclearmore » materials is then discussed, with an emphasis on improvements in accuracy that have been gained from measurements of multiple radioisotopic systems. Finally, papers that report on casework are reviewed, to provide a window into current scientific practice.« less

[Satanism and suicide in adolescence--2 case reports].

PubMed

Stiel, Michael; Madea, Burkhard

2002-01-01

Death cases--suicides as well as homicides--within the context of satanism are meanwhile becoming routine casework for forensic pathologists. Therefore the investigators should be aware of satanic signs and items associated with the occult to identify a satanic background. Based on two suicides of young persons, satanic signs helpful for classification are pointed out.

A PCR marker linked to a THCA synthase polymorphism is a reliable tool to discriminate potentially THC-rich plants of Cannabis sativa L.

PubMed

Staginnus, Christina; Zörntlein, Siegfried; de Meijer, Etienne

2014-07-01

Neither absolute THC content nor morphology allows the unequivocal discrimination of fiber cultivars and drug strains of Cannabis sativa L. unequivocally. However, the CBD/THC ratio remains constant throughout the plant's life cycle, is independent of environmental factors, and considered to be controlled by a single locus (B) with two codominant alleles (B(T) and B(D)). The homozygous B(T)/B(T) genotype underlies the THC-predominant phenotype, B(D)/B(D) is CBD predominant, and an intermediate phenotype is induced by the heterozygous state (B(T)/B(D)). Using PCR-based markers in two segregating populations, we proved that the THCA synthase gene represents the postulated B locus and that specific sequence polymorphisms are absolutely linked either to the THC-predominant or the THC-intermediate chemotype. The absolute linkage provides an excellent reliability of the marker signal in forensic casework. For validation, the species-specific marker system was applied to a large number of casework samples and fiber hemp cultivars. © 2014 American Academy of Forensic Sciences.

Nuclear Forensic Science: Analysis of Nuclear Material Out of Regulatory Control

DOE PAGES

Kristo, Michael J.; Gaffney, Amy M.; Marks, Naomi; ...

2016-05-11

Nuclear forensic science seeks to identify the origin of nuclear materials found outside regulatory control. It is increasingly recognized as an integral part of a robust nuclear security program. Our review highlights areas of active, evolving research in nuclear forensics, with a focus on analytical techniques commonly employed in Earth and planetary sciences. Applications of nuclear forensics to uranium ore concentrates (UOCs) are discussed first. UOCs have become an attractive target for nuclear forensic researchers because of the richness in impurities compared to materials produced later in the fuel cycle. Furthermore, the development of chronometric methods for age dating nuclearmore » materials is then discussed, with an emphasis on improvements in accuracy that have been gained from measurements of multiple radioisotopic systems. Finally, papers that report on casework are reviewed, to provide a window into current scientific practice.« less

An Ultra-High Discrimination Y Chromosome Short Tandem Repeat Multiplex DNA Typing System

PubMed Central

Hanson, Erin K.; Ballantyne, Jack

2007-01-01

In forensic casework, Y chromosome short tandem repeat markers (Y-STRs) are often used to identify a male donor DNA profile in the presence of excess quantities of female DNA, such as is found in many sexual assault investigations. Commercially available Y-STR multiplexes incorporating 12–17 loci are currently used in forensic casework (Promega's PowerPlex® Y and Applied Biosystems' AmpFlSTR® Yfiler®). Despite the robustness of these commercial multiplex Y-STR systems and the ability to discriminate two male individuals in most cases, the coincidence match probabilities between unrelated males are modest compared with the standard set of autosomal STR markers. Hence there is still a need to develop new multiplex systems to supplement these for those cases where additional discriminatory power is desired or where there is a coincidental Y-STR match between potential male participants. Over 400 Y-STR loci have been identified on the Y chromosome. While these have the potential to increase the discrimination potential afforded by the commercially available kits, many have not been well characterized. In the present work, 91 loci were tested for their relative ability to increase the discrimination potential of the commonly used ‘core’ Y-STR loci. The result of this extensive evaluation was the development of an ultra high discrimination (UHD) multiplex DNA typing system that allows for the robust co-amplification of 14 non-core Y-STR loci. Population studies with a mixed African American and American Caucasian sample set (n = 572) indicated that the overall discriminatory potential of the UHD multiplex was superior to all commercial kits tested. The combined use of the UHD multiplex and the Applied Biosystems' AmpFlSTR® Yfiler® kit resulted in 100% discrimination of all individuals within the sample set, which presages its potential to maximally augment currently available forensic casework markers. It could also find applications in human evolutionary genetics and genetic genealogy. PMID:17668066

Reverse engineering--rapid prototyping of the skull in forensic trauma analysis.

PubMed

Kettner, Mattias; Schmidt, Peter; Potente, Stefan; Ramsthaler, Frank; Schrodt, Michael

2011-07-01

Rapid prototyping (RP) comprises a variety of automated manufacturing techniques such as selective laser sintering (SLS), stereolithography, and three-dimensional printing (3DP), which use virtual 3D data sets to fabricate solid forms in a layer-by-layer technique. Despite a growing demand for (virtual) reconstruction models in daily forensic casework, maceration of the skull is frequently assigned to ensure haptic evidence presentation in the courtroom. Owing to the progress in the field of forensic radiology, 3D data sets of relevant cases are usually available to the forensic expert. Here, we present a first application of RP in forensic medicine using computed tomography scans for the fabrication of an SLS skull model in a case of fatal hammer impacts to the head. The report is intended to show that this method fully respects the dignity of the deceased and is consistent with medical ethics but nevertheless provides an excellent 3D impression of anatomical structures and injuries. © 2011 American Academy of Forensic Sciences.

Automated forensic DNA purification optimized for FTA card punches and identifiler STR-based PCR analysis.

PubMed

Tack, Lois C; Thomas, Michelle; Reich, Karl

2007-03-01

Forensic labs globally face the same problem-a growing need to process a greater number and wider variety of samples for DNA analysis. The same forensic lab can be tasked all at once with processing mixed casework samples from crime scenes, convicted offender samples for database entry, and tissue from tsunami victims for identification. Besides flexibility in the robotic system chosen for forensic automation, there is a need, for each sample type, to develop new methodology that is not only faster but also more reliable than past procedures. FTA is a chemical treatment of paper, unique to Whatman Bioscience, and is used for the stabilization and storage of biological samples. Here, the authors describe optimization of the Whatman FTA Purification Kit protocol for use with the AmpFlSTR Identifiler PCR Amplification Kit.

Virtopsy - the concept of a centralized database in forensic medicine for analysis and comparison of radiological and autopsy data.

PubMed

Aghayev, Emin; Staub, Lukas; Dirnhofer, Richard; Ambrose, Tony; Jackowski, Christian; Yen, Kathrin; Bolliger, Stephan; Christe, Andreas; Roeder, Christoph; Aebi, Max; Thali, Michael J

2008-04-01

Recent developments in clinical radiology have resulted in additional developments in the field of forensic radiology. After implementation of cross-sectional radiology and optical surface documentation in forensic medicine, difficulties in the validation and analysis of the acquired data was experienced. To address this problem and for the comparison of autopsy and radiological data a centralized database with internet technology for forensic cases was created. The main goals of the database are (1) creation of a digital and standardized documentation tool for forensic-radiological and pathological findings; (2) establishing a basis for validation of forensic cross-sectional radiology as a non-invasive examination method in forensic medicine that means comparing and evaluating the radiological and autopsy data and analyzing the accuracy of such data; and (3) providing a conduit for continuing research and education in forensic medicine. Considering the infrequent availability of CT or MRI for forensic institutions and the heterogeneous nature of case material in forensic medicine an evaluation of benefits and limitations of cross-sectional imaging concerning certain forensic features by a single institution may be of limited value. A centralized database permitting international forensic and cross disciplinary collaborations may provide important support for forensic-radiological casework and research.

Sampling flies or sampling flaws? Experimental design and inference strength in forensic entomology.

PubMed

Michaud, J-P; Schoenly, Kenneth G; Moreau, G

2012-01-01

Forensic entomology is an inferential science because postmortem interval estimates are based on the extrapolation of results obtained in field or laboratory settings. Although enormous gains in scientific understanding and methodological practice have been made in forensic entomology over the last few decades, a majority of the field studies we reviewed do not meet the standards for inference, which are 1) adequate replication, 2) independence of experimental units, and 3) experimental conditions that capture a representative range of natural variability. Using a mock case-study approach, we identify design flaws in field and lab experiments and suggest methodological solutions for increasing inference strength that can inform future casework. Suggestions for improving data reporting in future field studies are also proposed.

The novel primers for mammal species identification-based mitochondrial cytochrome b sequence: implication for reserved wild animals in Thailand and endangered mammal species in Southeast Asia.

PubMed

Muangkram, Yuttamol; Wajjwalku, Worawidh; Amano, Akira; Sukmak, Manakorn

2018-01-01

We presented the powerful techniques for species identification using the short amplicon of mitochondrial cytochrome b gene sequence. Two faecal samples and one single hair sample of the Asian tapir were tested using the new cytochrome b primers. The results showed a high sequence similarity with the mainland Asian tapir group. The comparative sequence analysis of the reserved wild mammals in Thailand and the other endangered mammal species from Southeast Asia comprehensibly verified the potential of our novel primers. The forward and reverse primers were 94.2 and 93.2%, respectively, by the average value of the sequence identity among 77 species sequences, and the overall mean distance was 35.9%. This development technique could provide rapid, simple, and reliable tools for species confirmation. Especially, it could recognize the problematic biological specimens contained less DNA material from illegal products and assist with wildlife crime investigation of threatened species and related forensic casework.

Expert disagreement in bitemark casework.

PubMed

Bowers, C Michael; Pretty, Iain A

2009-07-01

Bitemark cases continue to raise controversy due to the degree of expert disagreement which is frequently seen. Using a case mix of 49 bitemark cases from 2000 to 2007 each injury was independently assessed for its forensic significance using a previously described bitemark severity scale. Following the assessment, the mean value for the bites was categorized according to the crime type, the degree of expert agreement, and the judicial outcome. Results suggest that bitemarks found in child abuse cases have statistically significantly lower forensic value than those in other crime types, that bites where there is mutual agreement between experts will have higher forensic value than those where there is disagreement at trial, and that cases in which DNA has provided an exoneration will demonstrate similar quality to those where a conviction was secured. Forensic odontologists should carefully assess bitemark evidence and ensure that it meets certain minimums in relation to the presence of class and unique features before undertaking an analysis.

3D reconstruction of emergency cranial computed tomography scans as a tool in clinical forensic radiology after survived blunt head trauma--report of two cases.

PubMed

Grassberger, M; Gehl, A; Püschel, K; Turk, E E

2011-04-15

When requested to evaluate surviving victims of blunt head trauma the forensic expert has to draw mainly on medical documentation from the time of hospital admission. In many cases these consist of written clinical records, radiographs and in some cases photographic documentation of the injuries. We report two cases of survived severe blunt head trauma where CT images, which had primarily been obtained for clinical diagnostic purposes, were used for forensic assessment. 3D reconstructions of the clinical CT-images yielded valuable information regarding the sequence, number and direction of the impacts to the head, their gross morphology and the inflicting weapon. We conclude that computed tomography and related imaging methods, along with their 3D reconstruction capabilities, provide a useful tool to approach questions in clinical forensic casework. Copyright © 2010 Elsevier Ireland Ltd. All rights reserved.

Forensic botany: using plant evidence to aid in forensic death investigation.

PubMed

Miller Coyle, Heather; Lee, Cheng-Lung; Lin, Wen-Yu; Lee, Henry C; Palmbach, Timothy M

2005-08-01

Forensic botany is still an under-utilized resource in forensic casework, although it has been used on occasion. It is an area of specialty science that could include traditional botanical classification of species, DNA, or materials evidence (trace and transfer evidence), crime mapping or geo-sourcing, all dependent on the specific case application under consideration. Critical to the evaluation of plant evidence is careful collection, documentation, and preservation for later scientific analysis. This article reviews proper procedures and recent cases where botanical evidence played a role in establishing either manner or time of death. Plant evidence can be useful for determining if a death was due to an accident, suicide, or homicide, or what time of year burial may have taken place. In addition, plant evidence can be used to determine if a crime scene is a primary or secondary scene and to locate missing bodies.

Impurity profiling of trinitrotoluene using vacuum-outlet gas chromatography-mass spectrometry.

PubMed

Brust, Hanneke; Willemse, Sander; Zeng, Tuoyu; van Asten, Arian; Koeberg, Mattijs; van der Heijden, Antoine; Bolck, Annabel; Schoenmakers, Peter

2014-12-29

In this work, a reliable and robust vacuum-outlet gas chromatography-mass spectrometry (GC-MS) method is introduced for the identification and quantification of impurities in trinitrotoluene (TNT). Vacuum-outlet GC-MS allows for short analysis times; the analysis of impurities in TNT was performed in 4min. This study shows that impurity profiling of TNT can be used to investigate relations between TNT samples encountered in forensic casework. A wide variety of TNT samples were analyzed with the developed method. Dinitrobenzene, dinitrotoluene, trinitrotoluene and amino-dinitrotoluene isomers were detected at very low levels (<1wt.%) by applying the MS in selected-ion monitoring (SIM) mode. Limits of detection ranged from 6ng/mL for 2,6-dinitrotoluene to 43ng/mL for 4-amino-2,6-dinitrotoluene. Major impurities in TNT were 2,4-dinitrotoluene and 2,3,4-trinitrotoluene. Impurity profiles based on seven compounds showed to be useful to TNT samples from different sources. Statistical analysis of these impurity profiles using likelihood ratios demonstrated the potential to investigate whether two questioned TNT samples encountered in forensic casework are from the same source. Copyright © 2014 Elsevier B.V. All rights reserved.

Development of Highly Sensitive and Specific mRNA Multiplex System (XCYR1) for Forensic Human Body Fluids and Tissues Identification

PubMed Central

Xu, Yan; Xie, Jianhui; Cao, Yu; Zhou, Huaigu; Ping, Yuan; Chen, Liankang; Gu, Lihua; Hu, Wei; Bi, Gang; Ge, Jianye; Chen, Xin; Zhao, Ziqin

2014-01-01

The identification of human body fluids or tissues through mRNA-based profiling is very useful for forensic investigations. Previous studies have shown mRNA biomarkers are effective to identify the origin of biological samples. In this study, we selected 16 tissue specific biomarkers to evaluate their specificities and sensitivities for human body fluids and tissues identification, including porphobilinogen deaminase (PBGD), hemoglobin beta (HBB) and Glycophorin A (GLY) for circulatory blood, protamine 2 (PRM2) and transglutaminase 4 (TGM4) for semen, mucin 4 (MUC4) and human beta defensin 1(HBD1) for vaginal secretion, matrix metalloproteinases 7 and 11 (MMP7 and MMP11) for menstrual blood, keratin 4(KRT4) for oral mucosa, loricrin (LOR) and cystatin 6 (CST6) for skin, histatin 3(HTN3) for saliva, statherin (STATH) for nasal secretion, dermcidin (DCD) for sweat and uromodulin (UMOD) for urine. The above mentioned ten common forensic body fluids or tissues were used in the evaluation. Based on the evaluation, a reverse transcription (RT) PCR multiplex assay, XCYR1, which includes 12 biomarkers (i.e., HBB, GLY, HTN3, PRM2, KRT4, MMP11, MUC4, DCD, UMOD, MMP7, TGM4, and STATH) and 2 housekeeping genes [i.e., glyceraldehyde-3-phosphate dehydrogenase (GAPDH) and 18SrRNA], was developed. This assay was further validated with real casework samples and mock samples (with both single source and mixture) and it was approved that XCYR1 is effective to identify common body fluids or tissues (i.e., circulatory blood, saliva, semen, vaginal secretion, menstrual blood, oral mucosa, nasal secretion, sweat and urine) in forensic casework samples. PMID:24991806

Development of highly sensitive and specific mRNA multiplex system (XCYR1) for forensic human body fluids and tissues identification.

PubMed

Xu, Yan; Xie, Jianhui; Cao, Yu; Zhou, Huaigu; Ping, Yuan; Chen, Liankang; Gu, Lihua; Hu, Wei; Bi, Gang; Ge, Jianye; Chen, Xin; Zhao, Ziqin

2014-01-01

The identification of human body fluids or tissues through mRNA-based profiling is very useful for forensic investigations. Previous studies have shown mRNA biomarkers are effective to identify the origin of biological samples. In this study, we selected 16 tissue specific biomarkers to evaluate their specificities and sensitivities for human body fluids and tissues identification, including porphobilinogen deaminase (PBGD), hemoglobin beta (HBB) and Glycophorin A (GLY) for circulatory blood, protamine 2 (PRM2) and transglutaminase 4 (TGM4) for semen, mucin 4 (MUC4) and human beta defensin 1(HBD1) for vaginal secretion, matrix metalloproteinases 7 and 11 (MMP7 and MMP11) for menstrual blood, keratin 4(KRT4) for oral mucosa, loricrin (LOR) and cystatin 6 (CST6) for skin, histatin 3(HTN3) for saliva, statherin (STATH) for nasal secretion, dermcidin (DCD) for sweat and uromodulin (UMOD) for urine. The above mentioned ten common forensic body fluids or tissues were used in the evaluation. Based on the evaluation, a reverse transcription (RT) PCR multiplex assay, XCYR1, which includes 12 biomarkers (i.e., HBB, GLY, HTN3, PRM2, KRT4, MMP11, MUC4, DCD, UMOD, MMP7, TGM4, and STATH) and 2 housekeeping genes [i.e., glyceraldehyde-3-phosphate dehydrogenase (GAPDH) and 18SrRNA], was developed. This assay was further validated with real casework samples and mock samples (with both single source and mixture) and it was approved that XCYR1 is effective to identify common body fluids or tissues (i.e., circulatory blood, saliva, semen, vaginal secretion, menstrual blood, oral mucosa, nasal secretion, sweat and urine) in forensic casework samples.

Experimental and casework validation of ambient temperature corrections in forensic entomology.

PubMed

Johnson, Aidan P; Wallman, James F; Archer, Melanie S

2012-01-01

This paper expands on Archer (J Forensic Sci 49, 2004, 553), examining additional factors affecting ambient temperature correction of weather station data in forensic entomology. Sixteen hypothetical body discovery sites (BDSs) in Victoria and New South Wales (Australia), both in autumn and in summer, were compared to test whether the accuracy of correlation was affected by (i) length of correlation period; (ii) distance between BDS and weather station; and (iii) periodicity of ambient temperature measurements. The accuracy of correlations in data sets from real Victorian and NSW forensic entomology cases was also examined. Correlations increased weather data accuracy in all experiments, but significant differences in accuracy were found only between periodicity treatments. We found that a >5°C difference between average values of body in situ and correlation period weather station data was predictive of correlations that decreased the accuracy of ambient temperatures estimated using correlation. Practitioners should inspect their weather data sets for such differences. © 2011 American Academy of Forensic Sciences.

Forensic Mass Spectrometry

NASA Astrophysics Data System (ADS)

Hoffmann, William D.; Jackson, Glen P.

2015-07-01

Developments in forensic mass spectrometry tend to follow, rather than lead, the developments in other disciplines. Examples of techniques having forensic potential born independently of forensic applications include ambient ionization, imaging mass spectrometry, isotope ratio mass spectrometry, portable mass spectrometers, and hyphenated chromatography-mass spectrometry instruments, to name a few. Forensic science has the potential to benefit enormously from developments that are funded by other means, if only the infrastructure and personnel existed to adopt, validate, and implement the new technologies into casework. Perhaps one unique area in which forensic science is at the cutting edge is in the area of chemometrics and the determination of likelihood ratios for the evaluation of the weight of evidence. Such statistical techniques have been developed most extensively for ignitable-liquid residue analyses and isotope ratio analysis. This review attempts to capture the trends, motivating forces, and likely impact of developing areas of forensic mass spectrometry, with the caveat that none of this research is likely to have any real impact in the forensic community unless: (a) The instruments developed are turned into robust black boxes with red and green lights for positives and negatives, respectively, or (b) there are PhD graduates in the workforce who can help adopt these sophisticated techniques.

Hypothermia.

PubMed

Turk, Elisabeth E

2010-06-01

Hypothermia refers to a situation where there is a drop in body core temperature below 35 degrees C. It is a potentially fatal condition. In forensic medicine and pathology, cases of hypothermia often pose a special challenge to experts because of their complex nature, and the often absent or nonspecific nature of morphological findings. The scene of the incident may raise suspicions of a crime initially, due to phenomena such as terminal burrowing behavior and paradoxical undressing. An element of hypothermia often contributes to the cause of death in drug- and alcohol-related fatalities, in the homeless, in immersion deaths, in accidents and in cases of abuse or neglect, making the condition extremely relevant to forensic medical specialists. The aim of this review is to give an overview of the pathophysiological aspects of hypothermia and to illustrate different aspects relevant to forensic medical casework.

[Forensic aspects of gunshot suicides in Germany].

PubMed

Kunz, Sebastian Niko; Meyer, Harald J; Kraus, Sybille

2013-12-01

Suicidal gunshot wounds are a common appearance in forensic casework. The main task of the coroner lies in the detection of typical pathomorphological correlates, thus differentiating between homicide, suicide and accident. Apart from characteristic bloodstain patterns on the gun and shooting hand, the localisation of the entrance wound and the position of the weapon, additional details such as family background or medical history are important aspects of forensic investigation. An uncommon choice of weaponry and its unusual morphological manifestation often complicate the examination and reconstruction of such cases. Furthermore, due to social stigmatisation, the possibility of secondary changes by relatives at the crime scene should be considered. In addition to autopsy findings, a careful crime scene investigation and bloodstain pattern analysis, a ballistic reconstruction can be an essential tool to gain knowledge of the shooting distance and position of the gun.

Phylogenic analysis and forensic genetic characterization of Chinese Uyghur group via autosomal multi STR markers.

PubMed

Jin, Xiaoye; Wei, Yuanyuan; Chen, Jiangang; Kong, Tingting; Mu, Yuling; Guo, Yuxin; Dong, Qian; Xie, Tong; Meng, Haotian; Zhang, Meng; Li, Jianfei; Li, Xiaopeng; Zhu, Bofeng

2017-09-26

We investigated the allelic frequencies and forensic descriptive parameters of 23 autosomal short tandem repeat loci in a randomly selected sample of 1218 unrelated healthy Uyghur individuals residing in the Xinjiang Uyghur Autonomous Region, northwest China. A total of 281 alleles at these loci were identified and their corresponding allelic frequencies ranged from 0.0004 to 0.5390. The combined match probability and combined probability of exclusion of all loci were 5.192 × 10 -29 and 0.9999999996594, respectively. The results of population genetic study manifested that Uyghur had close relationships with those contiguous populations, such as Xibe and Hui groups. In a word, these autosomal short tandem repeat loci were highly informative in Uyghur group and the multiplex PCR system could be used as a valuable tool for forensic caseworks and population genetic analysis.

Biology and applications of human minisatellite loci.

PubMed

Armour, J A; Jeffreys, A J

1992-12-01

Highly repetitive minisatellites' include the most variable human loci described to date. They have proved invaluable in a wide variety of genetic analyses, and despite some controversies surrounding their practical implementation, have been extensively adopted in civil and forensic casework. Molecular analysis of internal allelic structure has provided detailed insights into the repeat-unit turnover mechanisms operating in germline mutations, which are ultimately responsible for the extreme variability seen at these loci.

Separation/extraction, detection, and interpretation of DNA mixtures in forensic science (review).

PubMed

Tao, Ruiyang; Wang, Shouyu; Zhang, Jiashuo; Zhang, Jingyi; Yang, Zihao; Sheng, Xiang; Hou, Yiping; Zhang, Suhua; Li, Chengtao

2018-05-25

Interpreting mixed DNA samples containing material from multiple contributors has long been considered a major challenge in forensic casework, especially when encountering low-template DNA (LT-DNA) or high-order mixtures that may involve missing alleles (dropout) and unrelated alleles (drop-in), among others. In the last decades, extraordinary progress has been made in the analysis of mixed DNA samples, which has led to increasing attention to this research field. The advent of new methods for the separation and extraction of DNA from mixtures, novel or jointly applied genetic markers for detection and reliable interpretation approaches for estimating the weight of evidence, as well as the powerful massively parallel sequencing (MPS) technology, has greatly extended the range of mixed samples that can be correctly analyzed. Here, we summarized the investigative approaches and progress in the field of forensic DNA mixture analysis, hoping to provide some assistance to forensic practitioners and to promote further development involving this issue.

Developmental Validation of Short Tandem Repeat Reagent Kit for Forensic DNA Profiling of Canine Biological Materials

PubMed Central

Dayton, Melody; Koskinen, Mikko T; Tom, Bradley K; Mattila, Anna-Maria; Johnston, Eric; Halverson, Joy; Fantin, Dennis; DeNise, Sue; Budowle, Bruce; Smith, David Glenn; Kanthaswamy, Sree

2009-01-01

Aim To develop a reagent kit that enables multiplex polymerase chain reaction (PCR) amplification of 18 short tandem repeats (STR) and the canine sex-determining Zinc Finger marker. Methods Validation studies to determine the robustness and reliability in forensic DNA typing of this multiplex assay included sensitivity testing, reproducibility studies, intra- and inter-locus color balance studies, annealing temperature and cycle number studies, peak height ratio determination, characterization of artifacts such as stutter percentages and dye blobs, mixture analyses, species-specificity, case type samples analyses and population studies. Results The kit robustly amplified domesticated dog samples and consistently generated full 19-locus profiles from as little as 125 pg of dog DNA. In addition, wolf DNA samples could be analyzed with the kit. Conclusion The kit, which produces robust, reliable, and reproducible results, will be made available for the forensic research community after modifications based on this study’s evaluation to comply with the quality standards expected for forensic casework. PMID:19480022

Phylogenic analysis and forensic genetic characterization of Chinese Uyghur group via autosomal multi STR markers

PubMed Central

Jin, Xiaoye; Wei, Yuanyuan; Chen, Jiangang; Kong, Tingting; Mu, Yuling; Guo, Yuxin; Dong, Qian; Xie, Tong; Meng, Haotian; Zhang, Meng; Li, Jianfei; Li, Xiaopeng; Zhu, Bofeng

2017-01-01

We investigated the allelic frequencies and forensic descriptive parameters of 23 autosomal short tandem repeat loci in a randomly selected sample of 1218 unrelated healthy Uyghur individuals residing in the Xinjiang Uyghur Autonomous Region, northwest China. A total of 281 alleles at these loci were identified and their corresponding allelic frequencies ranged from 0.0004 to 0.5390. The combined match probability and combined probability of exclusion of all loci were 5.192 × 10−29 and 0.9999999996594, respectively. The results of population genetic study manifested that Uyghur had close relationships with those contiguous populations, such as Xibe and Hui groups. In a word, these autosomal short tandem repeat loci were highly informative in Uyghur group and the multiplex PCR system could be used as a valuable tool for forensic caseworks and population genetic analysis. PMID:29088750

Mass spectrometry-based cDNA profiling as a potential tool for human body fluid identification.

PubMed

Donfack, Joseph; Wiley, Anissa

2015-05-01

Several mRNA markers have been exhaustively evaluated for the identification of human venous blood, saliva, and semen in forensic genetics. As new candidate human body fluid specific markers are discovered, evaluated, and reported in the scientific literature, there is an increasing trend toward determining the ideal markers for cDNA profiling of body fluids of forensic interest. However, it has not been determined which molecular genetics-based technique(s) should be utilized to assess the performance of these markers. In recent years, only a few confirmatory, mRNA/cDNA-based methods have been evaluated for applications in body fluid identification. The most frequently described methods tested to date include quantitative polymerase chain reaction (qPCR) and capillary electrophoresis (CE). However these methods, in particular qPCR, often favor narrow multiplex PCR due to the availability of a limited number of fluorescent dyes/tags. In an attempt to address this technological constraint, this study explored matrix-assisted laser desorption/ionization-time of flight mass spectrometry (MALDI-TOF MS) for human body fluid identification via cDNA profiling of venous blood, saliva, and semen. Using cDNA samples at 20pg input phosphoglycerate kinase 1 (PGK1) amounts, body fluid specific markers for the candidate genes were amplified in their corresponding body fluid (i.e., venous blood, saliva, or semen) and absent in the remaining two (100% specificity). The results of this study provide an initial indication that MALDI-TOF MS is a potential fluorescent dye-free alternative method for body fluid identification in forensic casework. However, the inherent issues of low amounts of mRNA, and the damage caused to mRNA by environmental exposures, extraction processes, and storage conditions are important factors that significantly hinder the implementation of cDNA profiling into forensic casework. Published by Elsevier Ireland Ltd.

Trace elemental analysis of glass and paint samples of forensic interest by ICP-MS using laser ablation solid sample introduction

NASA Astrophysics Data System (ADS)

Almirall, Jose R.; Trejos, Tatiana; Hobbs, Andria; Furton, Kenneth G.

2003-09-01

The importance of small amounts of glass and paint evidence as a means to associate a crime event to a suspect or a suspect to another individual has been demonstrated in many cases. Glass is a fragile material that is often found at the scenes of crimes such as burglaries, hit-and-run accidents and violent crime offenses. Previous work has demonstrated the utility of elemental analysis by solution ICP-MS of small amounts of glass for the comparison between a fragment found at a crime scene to a possible source of the glass. The multi-element capability and the sensitivity of ICP-MS combined with the simplified sample introduction of laser ablation prior to ion detection provides for an excellent and relatively non-destructive technique for elemental analysis of glass fragments. The direct solid sample introduction technique of laser ablation (LA) is reported as an alternative to the solution method. Direct solid sampling provides several advantages over solution methods and shows great potential for a number of solid sample analyses in forensic science. The advantages of laser ablation include the simplification of sample preparation, thereby reducing the time and complexity of the analysis, the elimination of handling acid dissolution reagents such as HF and the reduction of sources of interferences in the ionization plasma. Direct sampling also provides for essentially "non-destructive" sampling due to the removal of very small amounts of sample needed for analysis. The discrimination potential of LA-ICP-MS is compared with previously reported solution ICP-MS methods using external calibration with internal standardization and a newly reported solution isotope dilution (ID) method. A total of ninety-one different glass samples were used for the comparison study using the techniques mentioned. One set consisted of forty-five headlamps taken from a variety of automobiles representing a range of twenty years of manufacturing dates. A second set consisted of forty-six automotive glasses (side windows and windshields) representing casework glass from different vehicle manufacturers over several years was also characterized by RI and elemental composition analysis. The solution sample introduction techniques (external calibration and isotope dilution) provide for excellent sensitivity and precision but have the disadvantages of destroying the sample and also involve complex sample preparation. The laser ablation method was simpler, faster and produced comparable discrimination to the EC-ICP-MS and ID-ICP-MS. LA-ICP-MS can provide for an excellent alternative to solution analysis of glass in forensic casework samples. Paints and coatings are frequently encountered as trace evidence samples submitted to forensic science laboratories. A LA-ICP-MS method has been developed to complement the commonly used techniques in forensic laboratories in order to better characterize these samples for forensic purposes. Time-resolved plots of each sample can be compared to associate samples to each other or to discriminate between samples. Additionally, the concentration of lead and the ratios of other elements have been determined in various automotive paints by the reported method. A sample set of eighteen (18) survey automotive paint samples have been analyzed with the developed method in order to determine the utility of LA-ICP-MS and to compare the method to the more commonly used scanning electron microscopy (SEM) method for elemental characterization of paint layers in forensic casework.

Internal validation of STRmix™ for the interpretation of single source and mixed DNA profiles.

PubMed

Moretti, Tamyra R; Just, Rebecca S; Kehl, Susannah C; Willis, Leah E; Buckleton, John S; Bright, Jo-Anne; Taylor, Duncan A; Onorato, Anthony J

2017-07-01

The interpretation of DNA evidence can entail analysis of challenging STR typing results. Genotypes inferred from low quality or quantity specimens, or mixed DNA samples originating from multiple contributors, can result in weak or inconclusive match probabilities when a binary interpretation method and necessary thresholds (such as a stochastic threshold) are employed. Probabilistic genotyping approaches, such as fully continuous methods that incorporate empirically determined biological parameter models, enable usage of more of the profile information and reduce subjectivity in interpretation. As a result, software-based probabilistic analyses tend to produce more consistent and more informative results regarding potential contributors to DNA evidence. Studies to assess and internally validate the probabilistic genotyping software STRmix™ for casework usage at the Federal Bureau of Investigation Laboratory were conducted using lab-specific parameters and more than 300 single-source and mixed contributor profiles. Simulated forensic specimens, including constructed mixtures that included DNA from two to five donors across a broad range of template amounts and contributor proportions, were used to examine the sensitivity and specificity of the system via more than 60,000 tests comparing hundreds of known contributors and non-contributors to the specimens. Conditioned analyses, concurrent interpretation of amplification replicates, and application of an incorrect contributor number were also performed to further investigate software performance and probe the limitations of the system. In addition, the results from manual and probabilistic interpretation of both prepared and evidentiary mixtures were compared. The findings support that STRmix™ is sufficiently robust for implementation in forensic laboratories, offering numerous advantages over historical methods of DNA profile analysis and greater statistical power for the estimation of evidentiary weight, and can be used reliably in human identification testing. With few exceptions, likelihood ratio results reflected intuitively correct estimates of the weight of the genotype possibilities and known contributor genotypes. This comprehensive evaluation provides a model in accordance with SWGDAM recommendations for internal validation of a probabilistic genotyping system for DNA evidence interpretation. Copyright © 2017. Published by Elsevier B.V.

Population data of 24 STRs in Mexican-Mestizo population from Monterrey, Nuevo Leon (Northeast, Mexico) based on Powerplex(®) Fusion and GlobalFiler(®) kits.

PubMed

Ramos-González, Benito; Aguilar-Velázquez, José Alonso; Chávez-Briones, María de Lourdes; Delgado-Chavarría, Juan Ramón; Alfaro-Lopez, Elizabeth; Rangel-Villalobos, Héctor

2016-03-01

The STR loci included into new commercial human identification kits compels geneticists estimating forensic parameters for interpretation purposes in forensic casework. Therefore, we studied for the first time in Mexico the GlobalFiler(®) and Powerplex(®) Fusion systems in 326 and 682 unrelated individuals, respectively. These individuals are resident of the Monterrey City of the Nuevo Leon state (Northeast, Mexico). Population data from 23 autosomal STRs and the Y-STR locus DYS391 are reported and compared against available STR data from American ethnic groups and the unique Mexican population studied with Powerplex(®) Fusion. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

A novel cell culture model as a tool for forensic biology experiments and validations.

PubMed

Feine, Ilan; Shpitzen, Moshe; Roth, Jonathan; Gafny, Ron

2016-09-01

To improve and advance DNA forensic casework investigation outcomes, extensive field and laboratory experiments are carried out in a broad range of relevant branches, such as touch and trace DNA, secondary DNA transfer and contamination confinement. Moreover, the development of new forensic tools, for example new sampling appliances, by commercial companies requires ongoing validation and assessment by forensic scientists. A frequent challenge in these kinds of experiments and validations is the lack of a stable, reproducible and flexible biological reference material. As a possible solution, we present here a cell culture model based on skin-derived human dermal fibroblasts. Cultured cells were harvested, quantified and dried on glass slides. These slides were used in adhesive tape-lifting experiments and tests of DNA crossover confinement by UV irradiation. The use of this model enabled a simple and concise comparison between four adhesive tapes, as well as a straightforward demonstration of the effect of UV irradiation intensities on DNA quantity and degradation. In conclusion, we believe this model has great potential to serve as an efficient research tool in forensic biology. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

On compensation of mismatched recording conditions in the Bayesian approach for forensic automatic speaker recognition.

PubMed

Botti, F; Alexander, A; Drygajlo, A

2004-12-02

This paper deals with a procedure to compensate for mismatched recording conditions in forensic speaker recognition, using a statistical score normalization. Bayesian interpretation of the evidence in forensic automatic speaker recognition depends on three sets of recordings in order to perform forensic casework: reference (R) and control (C) recordings of the suspect, and a potential population database (P), as well as a questioned recording (QR) . The requirement of similar recording conditions between suspect control database (C) and the questioned recording (QR) is often not satisfied in real forensic cases. The aim of this paper is to investigate a procedure of normalization of scores, which is based on an adaptation of the Test-normalization (T-norm) [2] technique used in the speaker verification domain, to compensate for the mismatch. Polyphone IPSC-02 database and ASPIC (an automatic speaker recognition system developed by EPFL and IPS-UNIL in Lausanne, Switzerland) were used in order to test the normalization procedure. Experimental results for three different recording condition scenarios are presented using Tippett plots and the effect of the compensation on the evaluation of the strength of the evidence is discussed.

An overview of age estimation in forensic anthropology: perspectives and practical considerations.

PubMed

Márquez-Grant, Nicholas

2015-01-01

Information on methods of age estimation in physical anthropology, in particular with regard to age-at-death from human skeletal remains, is widely available in the literature. However, the practicalities and real challenges faced in forensic casework are not always highlighted. To provide a practitioner's perspective, regarding age estimation in forensic anthropology (both in the living as well as the dead), with an emphasis on the types of cases, the value of such work and its challenges and limitations. The paper reviews the current literature on age estimation with a focus on forensic anthropology, but it also brings the author's personal perspective derived from a number of forensic cases. Although much is known about what methods to use, but not always how to apply them, little attention has been given in the literature to the real practicalities faced by forensic anthropologists, for example: the challenges in different types of scenarios; how to report age estimations; responsibilities; and ethical concerns. This paper gathers some of these aspects into one overview which includes the value of such work and the practical challenges, not necessarily with the methods themselves, but also with regard to how these are applied in the different cases where age estimation is required.

Rapid quantification and sex determination of forensic evidence materials.

PubMed

Andréasson, Hanna; Allen, Marie

2003-11-01

DNA quantification of forensic evidence is very valuable for an optimal use of the available biological material. Moreover, sex determination is of great importance as additional information in criminal investigations as well as in identification of missing persons, no suspect cases, and ancient DNA studies. While routine forensic DNA analysis based on short tandem repeat markers includes a marker for sex determination, analysis of samples containing scarce amounts of DNA is often based on mitochondrial DNA, and sex determination is not performed. In order to allow quantification and simultaneous sex determination on minute amounts of DNA, an assay based on real-time PCR analysis of a marker within the human amelogenin gene has been developed. The sex determination is based on melting curve analysis, while an externally standardized kinetic analysis allows quantification of the nuclear DNA copy number in the sample. This real-time DNA quantification assay has proven to be highly sensitive, enabling quantification of single DNA copies. Although certain limitations were apparent, the system is a rapid, cost-effective, and flexible assay for analysis of forensic casework samples.

The (non)sense of routinely analysing beta-hydroxybutyric acid in forensic toxicology casework.

PubMed

Sadones, Nele; Lambert, Willy E; Stove, Christophe P

2017-05-01

Beta-hydroxybutyric acid (BHB) is a ketone body which is generated from fatty acids as an alternative energy source when glucose is not available. Determination of this compound may be relevant in the forensic laboratory as ketoacidosis - an elevated level of ketone bodies - may contribute to the cause of death. In this study, we aimed at determining the relevance of routinely implementing BHB analysis in the forensic toxicological laboratory, as BHB analysis typically requires an additional workload. We therefore performed an unbiased retrospective analysis of BHB in 599 cases, comprising 553 blood, 232 urine and 62 vitreous humour samples. Cases with BHB concentrations above 100mg/L (in blood, urine and/or vitreous humour) were invariably associated with elevated levels of acetone, another ketone body, the detection of which is already implemented in most forensic laboratories using the gas chromatographic procedure for ethanol quantification. Our retrospective analysis did not reveal any positive case that had been missed initially and confirms that BHB analysis can be limited to acetone positive cases. Copyright © 2017 Elsevier B.V. All rights reserved.

Analysis of dental injuries with clinical implications: A forensic case report.

PubMed

Tan, Si-Lei; Peng, Shu-Ya; Wan, Lei; Chen, Jie-Min; Xia, Wen-Tao

2018-01-01

Dental injuries, especially of the incisors, caused by punches in violent criminal attacks could be seen in daily forensic casework involving the identification of injuries to a living body. Sometimes, when there is neither circumstantial evidence nor information about the surrounding circumstances, it is difficult to discern the cause of these injuries and the manner in which they were inflicted. As an example of clinical forensic medicine, we present the case of a 58-year-old woman whose teeth were injured when fighting with her son-in-law over household affairs with no witnesses present. The two parties had conflicting stories about the cause of the woman's injury. The woman claimed that her teeth were lost while she was being beaten by her son-in-law, and the man argued that the damage to his mother-in-law's teeth was self-inflicted when she bit his fingers. The police attending the crime called for a forensic examination. Forensic practitioners analysed the mechanism of the tooth loss using multi-slice spiral computed tomography (MSCT) and imaging reconstruction technology. Local alveolar bone (medial alveolar) fracture and a small area of alveolar bone loss were found on MSCT. Thus, forensic medical experts speculated that the woman's lower central and lateral incisors were lost as a result of a violent attack and were not self-inflicted. Finally, forensic practitioners helped police in avoiding a miscarriage of justice and wrongful conviction.

RFLP and sequence analysis of the cytochrome b gene of selected animals and man: methodology and forensic application.

PubMed

Zehner, R; Zimmermann, S; Mebs, D

1998-01-01

To identify common animal species by analysis of the cytochrome b gene a method has been developed to obtain PCR products of a large domain of the cytochrome b gene (981 bp out of 1140 bp) in humans, selected mammals and birds using the same specifically designed primers. Species-specific RFLP patterns are generated by co-restriction with the restriction endonucleases ALU I and NCO I. The RFLP patterns obtained are conclusive even in mixtures of two or more species. The results were confirmed by sequence analysis which in addition explained intraspecies variations in the RFLP patterns. The method has been applied to forensic casework studies where the origin of roasted meat, stomach contents and a bone sample has been successfully identified.

The impact of human-technology cooperation and distributed cognition in forensic science: biasing effects of AFIS contextual information on human experts.

PubMed

Dror, Itiel E; Wertheim, Kasey; Fraser-Mackenzie, Peter; Walajtys, Jeff

2012-03-01

Experts play a critical role in forensic decision making, even when cognition is offloaded and distributed between human and machine. In this paper, we investigated the impact of using Automated Fingerprint Identification Systems (AFIS) on human decision makers. We provided 3680 AFIS lists (a total of 55,200 comparisons) to 23 latent fingerprint examiners as part of their normal casework. We manipulated the position of the matching print in the AFIS list. The data showed that latent fingerprint examiners were affected by the position of the matching print in terms of false exclusions and false inconclusives. Furthermore, the data showed that false identification errors were more likely at the top of the list and that such errors occurred even when the correct match was present further down the list. These effects need to be studied and considered carefully, so as to optimize human decision making when using technologies such as AFIS. © 2011 American Academy of Forensic Sciences.

Reanalysis of the Trotter Tibia Quandary and its Continued Effect on Stature Estimation of Past-Conflict Service Members.

PubMed

Lynch, Jeffrey James; Brown, Carrie; Palmiotto, Andrea; Maijanen, Heli; Damann, Franklin

2018-04-23

Forensic casework from past-conflicts relies on the corrected historical Trotter data for stature estimation in Fordisc. For roughly 10 years', stature estimation using this data has produced point estimates for the tibia that are on average 1.25 inches less than the other long bones. This issue was identified after applying the equations derived from Fordisc to the USS Oklahoma commingled assemblage. Reevaluation of Fordisc revealed that a correction factor of 20 mm, instead of 10 mm, was mistakenly applied to the Trotter tibia data. Historical forensic anthropology reports written at the Defense POW/MIA Accounting Agency were utilized to identify that the overcorrection is isolated to Fordisc 3 with an error rate of 5% of known antemortem statures falling outside of the prediction intervals that relied on the tibia. Further evaluation of the Oklahoma sample indicates the 10 mm correction is still producing point estimates less than the other long bones. © 2018 American Academy of Forensic Sciences.

The end of the (forensic science) world as we know it? The example of trace evidence

PubMed Central

Roux, Claude; Talbot-Wright, Benjamin; Robertson, James; Crispino, Frank; Ribaux, Olivier

2015-01-01

The dominant conception of forensic science as a patchwork of disciplines primarily assisting the criminal justice system (i.e. forensics) is in crisis or at least shows a series of anomalies and serious limitations. In recent years, symptoms of the crisis have been discussed in a number of reports by various commentators, without a doubt epitomized by the 2009 report by the US National Academies of Sciences (NAS 2009 Strengthening forensic science in the United States: a path forward). Although needed, but viewed as the solution to these drawbacks, the almost generalized adoption of stricter business models in forensic science casework compounded with ever-increasing normative and compliance processes not only place additional pressures on a discipline that already appears in difficulty, but also induce more fragmentation of the different forensic science tasks, a tenet many times denounced by the same NAS report and other similar reviews. One may ask whether these issues are not simply the result of an unfit paradigm. If this is the case, the current problems faced by forensic science may indicate future significant changes for the discipline. To facilitate broader discussion this presentation focuses on trace evidence, an area that is seminal to forensic science both for epistemological and historical reasons. There is, however, little doubt that this area is currently under siege worldwide. Current and future challenges faced by trace evidence are discussed along with some possible answers. The current situation ultimately presents some significant opportunities to re-invent not only trace evidence but also forensic science. Ultimately, a distinctive, more robust and more reliable science may emerge through rethinking the forensics paradigm built on specialisms, revisiting fundamental forensic science principles and adapting them to the twenty-first century. PMID:26101285

Using probabilistic theory to develop interpretation guidelines for Y-STR profiles.

PubMed

Taylor, Duncan; Bright, Jo-Anne; Buckleton, John

2016-03-01

Y-STR profiling makes up a small but important proportion of forensic DNA casework. Often Y-STR profiles are used when autosomal profiling has failed to yield an informative result. Consequently Y-STR profiles are often from the most challenging samples. In addition to these points, Y-STR loci are linked, meaning that evaluation of haplotype probabilities are either based on overly simplified counting methods or computationally costly genetic models, neither of which extend well to the evaluation of mixed Y-STR data. For all of these reasons Y-STR data analysis has not seen the same advances as autosomal STR data. We present here a probabilistic model for the interpretation of Y-STR data. Due to the fact that probabilistic systems for Y-STR data are still some way from reaching active casework, we also describe how data can be analysed in a continuous way to generate interpretational thresholds and guidelines. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Evaluation of Total Nitrite Pattern Visualization as an Improved Method for Gunshot Residue Detection and its Application to Casework Samples.

PubMed

Berger, Jason; Upton, Colin; Springer, Elyah

2018-04-23

Visualization of nitrite residues is essential in gunshot distance determination. Current protocols for the detection of nitrites include, among other tests, the Modified Griess Test (MGT). This method is limited as nitrite residues are unstable in the environment and limited to partially burned gunpowder. Previous research demonstrated the ability of alkaline hydrolysis to convert nitrates to nitrites, allowing visualization of unburned gunpowder particles using the MGT. This is referred to as Total Nitrite Pattern Visualization (TNV). TNV techniques were modified and a study conducted to streamline the procedure outlined in the literature to maximize the efficacy of the TNV in casework, while reducing the required time from 1 h to 5 min, and enhancing effectiveness on blood-soiled samples. The TNV method was found to provide significant improvement in the ability to detect significant nitrite residues, without sacrificing efficiency, that would allow for the determination of the muzzle-to-target distance. © 2018 American Academy of Forensic Sciences.

Determining the optimal forensic DNA analysis procedure following investigation of sample quality.

PubMed

Hedell, Ronny; Hedman, Johannes; Mostad, Petter

2018-07-01

Crime scene traces of various types are routinely sent to forensic laboratories for analysis, generally with the aim of addressing questions about the source of the trace. The laboratory may choose to analyse the samples in different ways depending on the type and quality of the sample, the importance of the case and the cost and performance of the available analysis methods. Theoretically well-founded guidelines for the choice of analysis method are, however, lacking in most situations. In this paper, it is shown how such guidelines can be created using Bayesian decision theory. The theory is applied to forensic DNA analysis, showing how the information from the initial qPCR analysis can be utilized. It is assumed the alternatives for analysis are using a standard short tandem repeat (STR) DNA analysis assay, using the standard assay and a complementary assay, or the analysis may be cancelled following quantification. The decision is based on information about the DNA amount and level of DNA degradation of the forensic sample, as well as case circumstances and the cost for analysis. Semi-continuous electropherogram models are used for simulation of DNA profiles and for computation of likelihood ratios. It is shown how tables and graphs, prepared beforehand, can be used to quickly find the optimal decision in forensic casework.

The role of 3DCT for the evaluation of chop injuries in clinical forensic medicine.

PubMed

Wittschieber, Daniel; Beck, Laura; Vieth, Volker; Hahnemann, Maria L

2016-09-01

As hatchet blows to the human head frequently cause fatal injuries, the forensic examination of survivors with cranial chop injuries is a rare phenomenon in forensic casework. Besides evaluation of clinical records, photographs, and medico-legal physical examination, the analysis and 3-dimensional reconstruction of pre-treatment computed tomography data (3DCT) must be considered an important and indispensable tool for the assessment of those cases because the characteristics of chopping trauma often appear masked or changed by clinical treatment. In the present article, the role of 3DCT for the evaluation of chop wounds in clinical forensic medicine is demonstrated by an illustrative case report of a young man who was attacked with a hatchet. 3DCT provides additional possibilities for supplementing missing information, such as number and direction of blows as well as weapon identification. Furthermore, 3DCT facilitates demonstration in court and understanding of medical lay people. We conclude that 3DCT is of particular value for the evaluation of survivors of life-threatening head and face injury. An increasing significance of this technique may be expected. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

The forensic value of X-linked markers in mixed-male DNA analysis.

PubMed

He, HaiJun; Zha, Lagabaiyila; Cai, JinHong; Huang, Jian

2018-05-04

Autosomal genetic markers and Y chromosome markers have been widely applied in analysis of mixed stains at crime scenes by forensic scientists. However, true genotype combinations are often difficult to distinguish using autosomal markers when similar amounts of DNA are contributed by multiple donors. In addition, specific individuals cannot be determined by Y chromosomal markers because male relatives share the same Y chromosome. X-linked markers, possessing characteristics somewhere intermediate between autosomes and the Y chromosome, are less universally applied in criminal casework. In this paper, X markers are proposed to apply to male mixtures because their true genes can be more easily and accurately recognized than the decision of the genotypes of AS markers. In this study, an actual two-man mixed stain from a forensic case file and simulated male-mixed DNA were examined simultaneously with the X markers and autosomal markers. Finally, the actual mixture was separated successfully by the X markers, although it was unresolved by AS-STRs, and the separation ratio of the simulated mixture was much higher using Chr X tools than with AS methods. We believe X-linked markers provide significant advantages in individual discrimination of male mixtures that should be further applied to forensic work.

Layering of stomach contents in drowning cases in post-mortem computed tomography compared to forensic autopsy.

PubMed

Gotsmy, Walther; Lombardo, Paolo; Jackowski, Christian; Brencicova, Eva; Zech, Wolf-Dieter

2018-04-24

In forensic autopsy, the analysis of stomach contents is important when investigating drowning cases. Three-layering of stomach contents may be interpreted as a diagnostic hint to drowning due to swallowing of larger amounts of water or other drowning media. The authors experienced frequent discrepancies of numbers of stomach content layering in drowning cases between post-mortem computed tomography (PMCT) and autopsy in forensic casework. Therefore, the goal of this study was to compare layering of stomach contents in drowning cases between PMCT and forensic autopsy. Drowning cases (n = 55; 40 male, 15 female, mean age 45.3 years; mean amount of stomach content 223 ml) that received PMCT prior to forensic autopsy were retrospectively analyzed by a forensic pathologist and a radiologist. Number of layers of stomach content in PMCT were compared to number of layers at forensic autopsy. In 28 of the 55 evaluated drowning cases, a discrepancy between layering of stomach contents at autopsy compared to PMCT was observed: 1 layer at autopsy (n = 28): 50% discrepancy to PMCT, 2 layers (n = 20): 45% discrepancy, and 3 layers (n = 7): 71.4% discrepancy. Sensitivity of correctly determining layering (as observed at forensic autopsy) in PMCT was 52% (positive predictive value 44.8%). Specificity was 46.6% (negative predictive value 53.8%). In a control group (n = 35) of non-drowning cases, three-layering of stomach contents was not observed. Discrepancies of observed numbers of stomach content layers between PMCT and forensic autopsy are a frequent finding possibly due to stomach content sampling technique at autopsy and movement of the corpse prior to PMCT and autopsy. Three-layering in PMCT, if indeed present, may be interpreted as a hint to drowning.

Forensic applications of desorption electrospray ionisation mass spectrometry (DESI-MS).

PubMed

Morelato, Marie; Beavis, Alison; Kirkbride, Paul; Roux, Claude

2013-03-10

Desorption electrospray ionisation mass spectrometry (DESI-MS) is an emerging analytical technique that enables in situ mass spectrometric analysis of specimens under ambient conditions. It has been successfully applied to a large range of forensically relevant materials. This review assesses and highlights forensic applications of DESI-MS including the analysis and detection of illicit drugs, explosives, chemical warfare agents, inks and documents, fingermarks, gunshot residues and drugs of abuse in urine and plasma specimens. The minimal specimen preparation required for analysis and the sensitivity of detection achieved offer great advantages, especially in the field of forensic science. Crown Copyright © 2013. Published by Elsevier Ireland Ltd. All rights reserved.

Forensic Fiber Examination and Analysis.

PubMed

Hauck, M M

2005-01-01

Fiber evidence suffers from the same misperception as many other types of trace evidence, that it is weak in its significance. Despite this pejorative perception, textiles make excellent evidence because of their presence in our daily lives and the variations they demonstrate. Fibers from the textiles in our and others' environments transfer from surface to surface and variously persist. Textile fibers are produced with specific raw materials, production methods, and postproduction alterations that create this variety. The distribution and use of the fibers add to their distinctive significance. The number of methods used in analysis helps to define and identify the fibers. Millions of color shades are possible in textiles and yet color analysis is not a universal technique in forensic laboratories. Transfer study after transfer study demonstrates the rarity of finding unrelated fibers at random that exhibit the same microscopic characteristics and optical properties. Examples from casework also demonstrate the usefulness of forensic textile fiber analysis in demonstrating probative associations in criminal investigations. Additional work needs to be done to fortify and support these conclusions and provide the verification necessary to remove the taint of "could have". Copyright © 2005 Central Police University.

Illustration and analysis of a coordinated approach to an effective forensic trace evidence capability.

PubMed

Stoney, David A; Stoney, Paul L

2015-08-01

An effective trace evidence capability is defined as one that exploits all useful particle types, chooses appropriate technologies to do so, and directly integrates the findings with case-specific problems. Limitations of current approaches inhibit the attainment of an effective capability and it has been strongly argued that a new approach to trace evidence analysis is essential. A hypothetical case example is presented to illustrate and analyze how forensic particle analysis can be used as a powerful practical tool in forensic investigations. The specifics in this example, including the casework investigation, laboratory analyses, and close professional interactions, provide focal points for subsequent analysis of how this outcome can be achieved. This leads to the specification of five key elements that are deemed necessary and sufficient for effective forensic particle analysis: (1) a dynamic forensic analytical approach, (2) concise and efficient protocols addressing particle combinations, (3) multidisciplinary capabilities of analysis and interpretation, (4) readily accessible external specialist resources, and (5) information integration and communication. A coordinating role, absent in current approaches to trace evidence analysis, is essential to achieving these elements. However, the level of expertise required for the coordinating role is readily attainable. Some additional laboratory protocols are also essential. However, none of these has greater staffing requirements than those routinely met by existing forensic trace evidence practitioners. The major challenges that remain are organizational acceptance, planning and implementation. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Investigating the Epigenetic Discrimination of Identical Twins Using Buccal Swabs, Saliva, and Cigarette Butts in the Forensic Setting.

PubMed

Vidaki, Athina; Kalamara, Vivian; Carnero-Montoro, Elena; Spector, Timothy D; Bell, Jordana T; Kayser, Manfred

2018-05-14

Monozygotic (MZ) twins are typically indistinguishable via forensic DNA profiling. Recently, we demonstrated that epigenetic differentiation of MZ twins is feasible; however, proportions of twin differentially methylated CpG sites (tDMSs) identified in reference-type blood DNA were not replicated in trace-type blood DNA. Here we investigated buccal swabs as typical forensic reference material, and saliva and cigarette butts as commonly encountered forensic trace materials. As an analog to a forensic case, we analyzed one MZ twin pair. Epigenome-wide microarray analysis in reference-type buccal DNA revealed 25 candidate tDMSs with >0.5 twin-to-twin differences. MethyLight quantitative PCR (qPCR) of 22 selected tDMSs in trace-type DNA revealed in saliva DNA that six tDMSs (27.3%) had >0.1 twin-to-twin differences, seven (31.8%) had smaller (<0.1) but robustly detected differences, whereas for nine (40.9%) the differences were in the opposite direction relative to the microarray data; for cigarette butt DNA, results were 50%, 22.7%, and 27.3%, respectively. The discrepancies between reference-type and trace-type DNA outcomes can be explained by cell composition differences, method-to-method variation, and other technical reasons including bisulfite conversion inefficiency. Our study highlights the importance of the DNA source and that careful characterization of biological and technical effects is needed before epigenetic MZ twin differentiation is applicable in forensic casework.

Simple and rapid screening procedure for 143 new psychoactive substances by liquid chromatography-tandem mass spectrometry.

PubMed

Adamowicz, Piotr; Tokarczyk, Bogdan

2016-07-01

In recent years, many new psychoactive substances (NPS) from several drug classes have appeared on the drug market. These substances, also known as 'legal highs', belong to different chemical classes. Despite the increasing number of NPS, there are few comprehensive screening methods for their detection in biological specimens. In this context, the purpose of this study was to develop a fast and simple liquid chromatography-tandem mass spectrometry (LC-MS/MS) screening procedure for NPS in blood. The elaborated method allows the simultaneous screening of 143 compounds from different groups (number of compounds): cathinones (36), phenethylamines (26), tryptamines (18), piperazines (9), piperidines (2), synthetic cannabinoids (34), arylalkylamines (7), arylcyclohexylamines (3), aminoindanes (2), and other drugs (6). Blood samples (0.2 mL) were precipitated with acetonitrile (0.6 mL). The separation was achieved with gradient mobile phase of 0.1% formic acid in acetonitrile and 0.1% formic acid in water in 14 min. Detection of all compounds was based on multiple reaction monitoring (MRM) transitions. The total number of transitions monitored in dynamic mode was 432. The whole procedure was rapid and simple. The limits of detection (LODs) estimated for 104 compounds were in the range 0.01-3.09 ng/mL. The extraction recoveries determined for 32 compounds were from 1.8 to 133%. The procedure was successfully applied to the analysis of forensic blood samples in routine casework. The developed method should have wide applicability for rapid screening of new drugs of abuse in forensic or clinical samples. The procedure can be easily expanded for more substances. Copyright © 2015 John Wiley & Sons, Ltd. Copyright © 2015 John Wiley & Sons, Ltd.

Facial soft biometric features for forensic face recognition.

PubMed

Tome, Pedro; Vera-Rodriguez, Ruben; Fierrez, Julian; Ortega-Garcia, Javier

2015-12-01

This paper proposes a functional feature-based approach useful for real forensic caseworks, based on the shape, orientation and size of facial traits, which can be considered as a soft biometric approach. The motivation of this work is to provide a set of facial features, which can be understood by non-experts such as judges and support the work of forensic examiners who, in practice, carry out a thorough manual comparison of face images paying special attention to the similarities and differences in shape and size of various facial traits. This new approach constitutes a tool that automatically converts a set of facial landmarks to a set of features (shape and size) corresponding to facial regions of forensic value. These features are furthermore evaluated in a population to generate statistics to support forensic examiners. The proposed features can also be used as additional information that can improve the performance of traditional face recognition systems. These features follow the forensic methodology and are obtained in a continuous and discrete manner from raw images. A statistical analysis is also carried out to study the stability, discrimination power and correlation of the proposed facial features on two realistic databases: MORPH and ATVS Forensic DB. Finally, the performance of both continuous and discrete features is analyzed using different similarity measures. Experimental results show high discrimination power and good recognition performance, especially for continuous features. A final fusion of the best systems configurations achieves rank 10 match results of 100% for ATVS database and 75% for MORPH database demonstrating the benefits of using this information in practice. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Evaluation of the impact of genetic linkage in forensic identity and relationship testing for expanded DNA marker sets.

PubMed

Tillmar, Andreas O; Phillips, Chris

2017-01-01

Advances in massively parallel sequencing technology have enabled the combination of a much-expanded number of DNA markers (notably STRs and SNPs in one or combined multiplexes), with the aim of increasing the weight of evidence in forensic casework. However, when data from multiple loci on the same chromosome are used, genetic linkage can affect the final likelihood calculation. In order to study the effect of linkage for different sets of markers we developed the biostatistical tool ILIR, (Impact of Linkage on forensic markers for Identity and Relationship tests). The ILIR tool can be used to study the overall impact of genetic linkage for an arbitrary set of markers used in forensic testing. Application of ILIR can be useful during marker selection and design of new marker panels, as well as being highly relevant for existing marker sets as a way to properly evaluate the effects of linkage on a case-by-case basis. ILIR, implemented via the open source platform R, includes variation and genomic position reference data for over 40 STRs and 140 SNPs, combined with the ability to include additional forensic markers of interest. The use of the software is demonstrated with examples from several different established marker sets (such as the expanded CODIS core loci) including a review of the interpretation of linked genetic data. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

High-throughput DNA extraction of forensic adhesive tapes.

PubMed

Forsberg, Christina; Jansson, Linda; Ansell, Ricky; Hedman, Johannes

2016-09-01

Tape-lifting has since its introduction in the early 2000's become a well-established sampling method in forensic DNA analysis. Sampling is quick and straightforward while the following DNA extraction is more challenging due to the "stickiness", rigidity and size of the tape. We have developed, validated and implemented a simple and efficient direct lysis DNA extraction protocol for adhesive tapes that requires limited manual labour. The method uses Chelex beads and is applied with SceneSafe FAST tape. This direct lysis protocol provided higher mean DNA yields than PrepFiler Express BTA on Automate Express, although the differences were not significant when using clothes worn in a controlled fashion as reference material (p=0.13 and p=0.34 for T-shirts and button-down shirts, respectively). Through in-house validation we show that the method is fit-for-purpose for application in casework, as it provides high DNA yields and amplifiability, as well as good reproducibility and DNA extract stability. After implementation in casework, the proportion of extracts with DNA concentrations above 0.01ng/μL increased from 71% to 76%. Apart from providing higher DNA yields compared with the previous method, the introduction of the developed direct lysis protocol also reduced the amount of manual labour by half and doubled the potential throughput for tapes at the laboratory. Generally, simplified manual protocols can serve as a cost-effective alternative to sophisticated automation solutions when the aim is to enable high-throughput DNA extraction of complex crime scene samples. Copyright © 2016 The Authors. Published by Elsevier Ireland Ltd.. All rights reserved.

"Flashburning"--interpreting the presence of heat damage to a suspect's clothing and footwear in the investigation of fires.

PubMed

Leung, Eric H; Halliday, David X

2010-12-01

When volatile flammable vapours are released, they can mix with surrounding air and form a vapour cloud. Ignition of this fuel/air mixture will produce a flame front that will flash through the vapour. Items exposed to the flame front, including a suspect's clothing and footwear, may sustain superficial heat damage. At The Forensic Science Service Ltd this is referred to as flashburning. This paper describes the concept of flashburning, the laboratory methodology used to identify it and how an assessment on the overall distribution of that damage may allow a scientist to evaluate its evidential significance. Two anonymised casework examples are used to demonstrate how this information has been interpreted and used in evidence in United Kingdom courts of law. Copyright © 2010 Forensic Science Society. Published by Elsevier Ireland Ltd. All rights reserved.

Forensic mycology: the use of fungi in criminal investigations.

PubMed

Hawksworth, David L; Wiltshire, Patricia E J

2011-03-20

This is the first overview to be published of the whole field of forensic mycology. It is based on all available information located in the literature, together with 13 examples from recent casework. Background information on fungi is given, and this is followed by an outline of the value, and potentially wide application, of mycology in criminal investigation. Applications include roles in: providing trace evidence; estimating time since death (post-mortem interval); ascertaining time of deposition; investigating cause of death, hallucinations, or poisonings; locating buried corpses; and biological warfare. Previous work has been critically evaluated, with particular attention to its evidential value, and suitability for presentation in a court of law. The situations where mycology might assist an investigation are summarised, and issues relating to the further development of the subject are presented. A comprehensive bibliography with 120 citations is provided. Copyright © 2010 Elsevier Ireland Ltd. All rights reserved.

DNA Profiles from Fingerprint Lifts-Enhancing the Evidential Value of Fingermarks Through Successful DNA Typing.

PubMed

Subhani, Zuhaib; Daniel, Barbara; Frascione, Nunzianda

2018-05-25

This study evaluated the compatibility of the most common enhancement methods and lifting techniques with DNA profiling. Emphasis is placed on modern lifting techniques (i.e., gelatin lifters and Isomark™) and historical fingerprint lifts for which limited research has been previously conducted. A total of 180 fingerprints were deposited on a glass surface, enhanced, lifted, and processed for DNA typing. DNA could be extracted and profiled for all the powders and lifts tested and from both groomed fingerprints and natural prints with no significant difference in the percentage of profile recovered. DNA profiles could also be obtained from historical fingerprint lifts (79.2% of 72 lifts) with one or more alleles detected. These results demonstrate the compatibility between different powder/lift combinations and DNA profiling therefore augmenting the evidential value of fingerprints in forensic casework. © 2018 American Academy of Forensic Sciences.

Acetone facilitated DNA sampling from electrical tapes improves DNA recovery and enables latent fingerprints development.

PubMed

Feine, Ilan; Shpitzen, Moshe; Geller, Boris; Salmon, Eran; Peleg, Tsach; Roth, Jonathan; Gafny, Ron

2017-07-01

Electrical tapes (ETs) are a common component of improvised explosive devices (IEDs) used by terrorists or criminal organizations and represent a valuable forensic resource for DNA and latent fingerprints recovery. However, DNA recovery rates are typically low and usually below the minimal amount required for amplification. In addition, most DNA extraction methods are destructive and do not allow further latent fingerprints development. In the present study a cell culture based touch DNA model was used to demonstrate a two-step acetone-water DNA recovery protocol from ETs. This protocol involves only the adhesive side of the ET and increases DNA recovery rates by up to 70%. In addition, we demonstrated partially successful latent fingerprints development from the non-sticky side of the ETs. Taken together, this protocol maximizes the forensic examination of ETs and is recommended for routine casework processing. Copyright © 2017 Elsevier B.V. All rights reserved.

Measuring the Rarity of Fingerprint Patterns in the Dutch Population Using an Extended Classification Set.

PubMed

de Jongh, Arent; Lubach, Anko R; Lie Kwie, Sheryl L; Alberink, Ivo

2018-06-11

Latent print examiners often use their experience and knowledge to reach a conclusion on the identity of the source. Their conclusion is primarily based on their personal opinion on the rarity of the matching fingerprint features. Fingerprint patterns, if present, can play a significant role in the final assessment of a match. The authors believe that statistical data on the rarity of fingerprint patterns strengthens the subjective evaluation of the corresponding information. In order to provide fingerprint examiners with additional numerical support, fingerprint patterns were manually classified in a set of 24,104 fingerprints. In this study the frequencies of occurrence of 35 different fingerprint patterns have been obtained. The frequency data presented in this study can be used in the ACE-V process applied in forensic casework, allowing for the assessment of the evidential strength related to a specific fingerprint pattern type. © 2018 American Academy of Forensic Sciences.

Are Forensic Experts Already Biased before Adversarial Legal Parties Hire Them?

PubMed Central

2016-01-01

This survey of 206 forensic psychologists tested the “filtering” effects of preexisting expert attitudes in adversarial proceedings. Results confirmed the hypothesis that evaluator attitudes toward capital punishment influence willingness to accept capital case referrals from particular adversarial parties. Stronger death penalty opposition was associated with higher willingness to conduct evaluations for the defense and higher likelihood of rejecting referrals from all sources. Conversely, stronger support was associated with higher willingness to be involved in capital cases generally, regardless of referral source. The findings raise the specter of skewed evaluator involvement in capital evaluations, where evaluators willing to do capital casework may have stronger capital punishment support than evaluators who opt out, and evaluators with strong opposition may work selectively for the defense. The results may provide a partial explanation for the “allegiance effect” in adversarial legal settings such that preexisting attitudes may contribute to partisan participation through a self-selection process. PMID:27124416

The end of the (forensic science) world as we know it? The example of trace evidence.

PubMed

Roux, Claude; Talbot-Wright, Benjamin; Robertson, James; Crispino, Frank; Ribaux, Olivier

2015-08-05

The dominant conception of forensic science as a patchwork of disciplines primarily assisting the criminal justice system (i.e. forensics) is in crisis or at least shows a series of anomalies and serious limitations. In recent years, symptoms of the crisis have been discussed in a number of reports by various commentators, without a doubt epitomized by the 2009 report by the US National Academies of Sciences (NAS 2009 Strengthening forensic science in the United States: a path forward). Although needed, but viewed as the solution to these drawbacks, the almost generalized adoption of stricter business models in forensic science casework compounded with ever-increasing normative and compliance processes not only place additional pressures on a discipline that already appears in difficulty, but also induce more fragmentation of the different forensic science tasks, a tenet many times denounced by the same NAS report and other similar reviews. One may ask whether these issues are not simply the result of an unfit paradigm. If this is the case, the current problems faced by forensic science may indicate future significant changes for the discipline. To facilitate broader discussion this presentation focuses on trace evidence, an area that is seminal to forensic science both for epistemological and historical reasons. There is, however, little doubt that this area is currently under siege worldwide. Current and future challenges faced by trace evidence are discussed along with some possible answers. The current situation ultimately presents some significant opportunities to re-invent not only trace evidence but also forensic science. Ultimately, a distinctive, more robust and more reliable science may emerge through rethinking the forensics paradigm built on specialisms, revisiting fundamental forensic science principles and adapting them to the twenty-first century. © 2015 The Author(s) Published by the Royal Society. All rights reserved.

Analysis of transferred fragrance and its forensic implications.

PubMed

Gherghel, Simona; Morgan, Ruth M; Blackman, Christopher S; Karu, Kersti; Parkin, Ivan P

2016-12-01

Perfumes are widely used by many people in developed countries, and a large number of both men and women wear perfumes on a daily basis. Analysis of perfume trace materials from clothing is not commonly employed within forensic casework, yet as a form of trace evidence it has the potential to provide valuable intelligence. In order to appreciate the value of trace evidence there is a fundamental need for an evidence base that can both offer insight into how a trace material behaves under different scenarios and activities, and from which inferences can be made. With this purpose a gas chromatography-mass spectrometry method for trace analysis of perfumes was developed. This paper presents two different series of experiments that investigate the dynamics of perfume transfer as a factor of perfume ageing time, and as a factor of perfume contact time. Empirical data showed that both perfume ageing time, and perfume contact time play a key role in the number of perfume components transferred. These studies have implication for forensic protocols, specifically for perfume trace evidence collection, analysis, interpretation, and presentation, and there is potentially great value in analysing perfumes from clothing exhibits in forensic enquiries that involve close contact between individuals, such as sexual assaults. Copyright © 2016 The Authors. Published by Elsevier Ireland Ltd.. All rights reserved.

Development of mRNA-based body fluid identification using reverse transcription loop-mediated isothermal amplification.

PubMed

Satoh, Tetsuya; Kouroki, Seiya; Ogawa, Keita; Tanaka, Yorika; Matsumura, Kazutoshi; Iwase, Susumu

2018-04-25

Identifying body fluids from forensic samples can provide valuable evidence for criminal investigations. Messenger RNA (mRNA)-based body fluid identification was recently developed, and highly sensitive parallel identification using reverse transcription polymerase chain reaction (RT-PCR) has been described. In this study, we developed reverse transcription loop-mediated isothermal amplification (RT-LAMP) as a simple, rapid assay for identifying three common forensic body fluids, namely blood, semen, and saliva, and evaluated its specificity and sensitivity. Hemoglobin beta (HBB), transglutaminase 4 (TGM4), and statherin (STATH) were selected as marker genes for blood, semen, and saliva, respectively. RT-LAMP could be performed in a single step including both reverse transcription and DNA amplification under an isothermal condition within 60 min, and detection could be conveniently performed via visual fluorescence. Marker-specific amplification was performed in each assay, and no cross-reaction was observed among five representative forensically relevant body fluids. The detection limits of the assays were 0.3 nL, 30 nL, and 0.3 μL for blood, semen, and saliva, respectively, and their sensitivities were comparable with those of RT-PCR. Furthermore, RT-LAMP assays were applicable to forensic casework samples. It is considered that RT-LAMP is useful for body fluid identification.

Are the evidences of forensic entomology preserved in ethanol suitable for SEM studies?

PubMed

López-Esclapez, Raquel; García, María-Dolores; Arnaldos, María-Isabel; Presa, Juan José; Ubero-Pascal, Nicolás

2014-07-01

In forensic practice, the use of arthropod evidences to estimate the postmortem interval is a very good approach when the elapsed time from death is long, but it requires the correct identification of the specimens. This is a crucial step, not always easy to achieve, in particular when dealing with immature specimens. In this case, scanning electronic microscopy (SEM) can be useful, but the techniques used to preserve specimens in forensic practice are usually different from those used to prepare specimens for SEM studies. To determine whether forensic evidences preserving techniques are also compatible with SEM analysis, we have compared specimens of all the immature stages of Calliphora vicina Robineau-Desvoidy, 1830 (Diptera, Calliphoridae) preserved in 70% ethanol, with others prepared with aldehydic fixative techniques that are more appropriate for SEM studies. At the same time, two drying techniques have also been compared with both fixative techniques, the critical point drying and air-drying following with hexamethyldisilizane treatment (HMDS). Our results indicate that there are not basis against recommending the use of ethanol to preserve forensic entomological evidences and that both drying methods appear to offer good results for second and third instar larvae, although HMDS behaves better with eggs and pupae. Copyright © 2014 Elsevier Ltd. All rights reserved.

Review of forensically important entomological specimens collected from human cadavers in Malaysia (2005-2010).

PubMed

Kavitha, Rajagopal; Nazni, Wasi Ahmad; Tan, Tian Chye; Lee, Han Lim; Azirun, Mohd Sofian

2013-07-01

Forensic entomological specimens collected from human decedents during crime scene investigations in Malaysia in the past 6 years (2005-2010) are reviewed. A total of 80 cases were recorded and 93 specimens were collected. From these specimens, 10 species of cyclorrphagic flies were identified, consisting of Chrysomya rufifacies (Macquart) -38 specimens (40.86%), Chrysomya megacephala (Fabricius) -36 specimens (38.70%), Chrysomya villeneuvi (Patton) -2 specimens (2.15%), Chrysomya nigripes (Aubertin) -2 specimens (2.15%), Chrysomya pinguis (Walker) -1 specimen (1.08%), Hermetia illucens (Linnaeus) -1 specimen (1.08%), Hemipyrellia liguriens (Wiedemann) -5 specimens (5.37%), Synthesiomyia nudiseta (Wulp) -1 specimen (1.08%), Megaselia scalaris (Loew)-1 specimen (1.08%) and Sarcophaga ruficornis (Fabricius) -4 specimens (4.30%). In two specimens (2.15%), the maggots were not identifiable. Ch. megacephala and Ch. rufifacies were the commonest species found in human decedents from three different ecological habitats. S. nudiseta is an uncommon species found only on human cadavers from indoors. A total of 75 cases (93.75%) had a single fly infestation and 5 cases (6.25%) had double fly infestation. In conclusion, although large numbers of fly species were found on human decedents, the predominant species are still those of Chrysomya. Copyright © 2013 Elsevier Ltd and Faculty of Forensic and Legal Medicine. All rights reserved.

Forensic SNP genotyping with SNaPshot: Technical considerations for the development and optimization of multiplexed SNP assays.

PubMed

Fondevila, M; Børsting, C; Phillips, C; de la Puente, M; Consortium, Euroforen-NoE; Carracedo, A; Morling, N; Lareu, M V

2017-01-01

This review explores the key factors that influence the optimization, routine use, and profile interpretation of the SNaPshot single-base extension (SBE) system applied to forensic single-nucleotide polymorphism (SNP) genotyping. Despite being a mainly complimentary DNA genotyping technique to routine STR profiling, use of SNaPshot is an important part of the development of SNP sets for a wide range of forensic applications with these markers, from genotyping highly degraded DNA with very short amplicons to the introduction of SNPs to ascertain the ancestry and physical characteristics of an unidentified contact trace donor. However, this technology, as resourceful as it is, displays several features that depart from the usual STR genotyping far enough to demand a certain degree of expertise from the forensic analyst before tackling the complex casework on which SNaPshot application provides an advantage. In order to provide the basis for developing such expertise, we cover in this paper the most challenging aspects of the SNaPshot technology, focusing on the steps taken to design primer sets, optimize the PCR and single-base extension chemistries, and the important features of the peak patterns observed in typical forensic SNP profiles using SNaPshot. With that purpose in mind, we provide guidelines and troubleshooting for multiplex-SNaPshot-oriented primer design and the resulting capillary electrophoresis (CE) profile interpretation (covering the most commonly observed artifacts and expected departures from the ideal conditions). Copyright © 2017 Central Police University.

Postmortem CT versus forensic autopsy: frequent discrepancies of tracheobronchial content findings.

PubMed

Zech, Wolf-Dieter; Jackowski, Christian; Schwendener, Nicole; Brencicova, Eva; Schuster, Frederick; Lombardo, Paolo

2016-01-01

In their daily forensic casework, the authors experienced discrepancies of tracheobronchial content findings between postmortem computed tomography (PMCT) and autopsy to an extent previously unnoticed in the literature. The goal of this study was to evaluate such discrepancies in routine forensic cases. A total of 327 cases that underwent PMCT prior to routine forensic autopsy were retrospectively evaluated for tracheal and bronchial contents according to PMCT and autopsy findings. Hounsfield unit (HU) values of tracheobronchial contents, causes of death, and presence of pulmonary edema were assessed in mismatching and matching cases. Comparing contents in PMCT and autopsy in each of the separately evaluated compartments of the respiratory tract low positive predictive values were assessed (trachea, 38.2%; main bronchi, 40%; peripheral bronchi, 69.1%) indicating high discrepancy rates. The majority of tracheobronchial contents were viscous stomach contents in matching cases and low radiodensity materials (i.e., HU < 30) in mismatching cases. The majority of causes of death were cardiac related in the matching cases and skull/brain trauma in the mismatching cases. In mismatching cases, frequency of pulmonary edema was significantly higher than in matching cases. It can be concluded that discrepancies in tracheobronchial contents observed between PMCT and routine forensic autopsy occur in a considerable number of cases. Discrepancies may be explained by the runoff of contents via nose and mouth during external examination and the flow back of tracheal and main bronchial contents into the lungs caused by upright movement of the respiratory tract at autopsy.

Collection of biological samples in forensic toxicology.

PubMed

Dinis-Oliveira, R J; Carvalho, F; Duarte, J A; Remião, F; Marques, A; Santos, A; Magalhães, T

2010-09-01

Forensic toxicology is the study and practice of the application of toxicology to the purposes of the law. The relevance of any finding is determined, in the first instance, by the nature and integrity of the specimen(s) submitted for analysis. This means that there are several specific challenges to select and collect specimens for ante-mortem and post-mortem toxicology investigation. Post-mortem specimens may be numerous and can endow some special difficulties compared to clinical specimens, namely those resulting from autolytic and putrefactive changes. Storage stability is also an important issue to be considered during the pre-analytic phase, since its consideration should facilitate the assessment of sample quality and the analytical result obtained from that sample. The knowledge on degradation mechanisms and methods to increase storage stability may enable the forensic toxicologist to circumvent possible difficulties. Therefore, advantages and limitations of specimen preservation procedures are thoroughfully discussed in this review. Presently, harmonized protocols for sampling in suspected intoxications would have obvious utility. In the present article an overview is given on sampling procedures for routinely collected specimens as well as on alternative specimens that may provide additional information on the route and timing of exposure to a specific xenobiotic. Last, but not least, a discussion on possible bias that can influence the interpretation of toxicological results is provided. This comprehensive review article is intented as a significant help for forensic toxicologists to accomplish their frequently overwhelming mission.

Contamination during criminal investigation: Detecting police contamination and secondary DNA transfer from evidence bags.

PubMed

Fonneløp, Ane Elida; Johannessen, Helen; Egeland, Thore; Gill, Peter

2016-07-01

As the profiling systems used in forensic analyses have become more sensitive in recent years, the risk of detecting a contamination in a DNA sample has increased proportionally. This requires more stringent work protocols and awareness to minimize the chance of contamination. Although there is high consciousness on contamination and best practice procedures in forensic labs, the same requirements are not always applied by the police. In this study we have investigated the risk of contamination from police staff. Environmental DNA was monitored by performing wipe tests (sampling of hot spots) at two large police units (scenes of crime departments). Additionally, the DNA profiles of the scenes of crime officers were compared to casework samples that their own unit had investigated in the period of 2009-2015. Furthermore, a pilot study to assess whether DNA from the outside package of an exhibit could be transferred to a DNA sample was carried out. Environmental DNA was detected in various samples from hot spots. Furthermore, 16 incidences of previously undetected police-staff contamination were found in casework that had been submitted between 2009 and 2015. In 6 cases the police officers with a matching DNA profile reported that they had not been involved with the case. We have demonstrated that DNA from the outside package can be transferred to an exhibit during examination. This experience demonstrates that when implementing the new multiplex systems, it is important to ensure that 'best practice' procedures are upgraded, and appropriate training is provided in order to ensure that police are aware of the increased contamination risks. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Multiplex fluorescent PCR for noninvasive prenatal detection of fetal-derived paternally inherited diseases using circulatory fetal DNA in maternal plasma.

PubMed

Tang, Dong-ling; Li, Yan; Zhou, Xin; Li, Xia; Zheng, Fang

2009-05-01

To develop a fluorescent polymerase chain reaction (PCR) assay for the detection of circulating fetal DNA in maternal plasma and use the established multiplex in noninvasive prenatal genetic diagnosis and its further applications in forensic casework. The DNA template was extracted from 47 pregnant women and the whole blood samples from the stated biological fathers were used to detect genotype. Using multiplex fluorescent PCR at 16 different polymorphic short tandem repeat (STR) loci, maternal DNA extracted from plasma samples at early pregnancy, medium pregnancy and late pregnancy were used to detect genotype. Their husbands' DNA was also used for fetal genotype ascertainment. Multiplex fluorescent PCR with 16 polymorphic short tandem repeats revealed the presence of fetal DNA in all cases. Every pregnant women/husband pair was informative in at least 3 of 16 loci. The chances of detecting paternally inherited fetal alleles ranged from 66.67 to 94.12%. They are 66.67% in early pregnancy, 85.71% in medium pregnancy and 94.12% in late pregnancy. The accuracy of Multiplex PCR assay to detect fetal DNA was 100%. Circulating fetal DNA analysis can be used as a possible alternative tool in routine laboratory prenatal diagnosis in the near future; this highly polymorphic STR multiplex has greatly improved the chances of detecting paternally inherited fetal alleles compared with other fetal DNA detection systems that use fetus-derived Y sequences to detect only male fetal DNA in maternal plasma. Our proposed technique can be applied to both female and male fetuses, which provides a sensitive, accurate and efficient method for noninvasive prenatal genetic diagnosis and forensic casework.

Forensically Important Blow Flies Chrysomya pinguis, C. villeneuvi, and Lucilia porphyrina (Diptera: Calliphoridae) in a Case of Human Remains in Thailand.

PubMed

Monum, Tawatchai; Sukontason, Kabkaew L; Sribanditmongkol, Pongruk; Sukontason, Kom; Samerjai, Chutharat; Limsopatham, Kwankamol; Suwannayod, Suttida; Klong-Klaew, Tunwadee; Wannasan, Anchalee

2017-02-01

This is the first study to report Chrysomya pinguis (Walker) and Lucilia porphyrina (Walker) (Diptera: Calliphoridae) as forensically important blow fly species from human cadavers in Thailand, in addition to Chrysomya villeneuvi (Patton) already known in Thailand. In 2016, a fully decomposed body of an unknown adult male was discovered in a high mountainous forest during winter in Chiang Mai province. The remains were infested heavily with thousands of blow fly larvae feeding simultaneously on them. Morphological identification of adults reared from the larvae, and molecular analysis based on sequencing of 1,247 bp partial mitochondrial cytochrome c oxidase subunit 1 gene ( CO1 ) of the larvae and puparia, confirmed the above mentioned 3 species. The approving forensic fly evidence by molecular approach was described for the first time in Thailand. Moreover, neighbor-joining phylogenetic analysis of the CO1 was performed to compare the relatedness of the species, thereby affirming the accuracy of identification. As species of entomofauna varies among cases in different geographic and climatic circumstances, C. pinguis and L. porphyrina were added to the list of Thai forensic entomology caseworks, including colonizers of human remains in open, high mountainous areas during winter. Further research should focus on these 3 species, for which no developmental data are currently available.

Forensically Important Blow Flies Chrysomya pinguis, C. villeneuvi, and Lucilia porphyrina (Diptera: Calliphoridae) in a Case of Human Remains in Thailand

PubMed Central

Monum, Tawatchai; Sukontason, Kabkaew L.; Sribanditmongkol, Pongruk; Sukontason, Kom; Samerjai, Chutharat; Limsopatham, Kwankamol; Suwannayod, Suttida; Klong-klaew, Tunwadee; Wannasan, Anchalee

2017-01-01

This is the first study to report Chrysomya pinguis (Walker) and Lucilia porphyrina (Walker) (Diptera: Calliphoridae) as forensically important blow fly species from human cadavers in Thailand, in addition to Chrysomya villeneuvi (Patton) already known in Thailand. In 2016, a fully decomposed body of an unknown adult male was discovered in a high mountainous forest during winter in Chiang Mai province. The remains were infested heavily with thousands of blow fly larvae feeding simultaneously on them. Morphological identification of adults reared from the larvae, and molecular analysis based on sequencing of 1,247 bp partial mitochondrial cytochrome c oxidase subunit 1 gene (CO1) of the larvae and puparia, confirmed the above mentioned 3 species. The approving forensic fly evidence by molecular approach was described for the first time in Thailand. Moreover, neighbor-joining phylogenetic analysis of the CO1 was performed to compare the relatedness of the species, thereby affirming the accuracy of identification. As species of entomofauna varies among cases in different geographic and climatic circumstances, C. pinguis and L. porphyrina were added to the list of Thai forensic entomology caseworks, including colonizers of human remains in open, high mountainous areas during winter. Further research should focus on these 3 species, for which no developmental data are currently available. PMID:28285509

The GHEP–EMPOP collaboration on mtDNA population data—A new resource for forensic casework

PubMed Central

Prieto, L.; Zimmermann, B.; Goios, A.; Rodriguez-Monge, A.; Paneto, G.G.; Alves, C.; Alonso, A.; Fridman, C.; Cardoso, S.; Lima, G.; Anjos, M.J.; Whittle, M.R.; Montesino, M.; Cicarelli, R.M.B.; Rocha, A.M.; Albarrán, C.; de Pancorbo, M.M.; Pinheiro, M.F.; Carvalho, M.; Sumita, D.R.; Parson, W.

2011-01-01

Mitochondrial DNA (mtDNA) population data for forensic purposes are still scarce for some populations, which may limit the evaluation of forensic evidence especially when the rarity of a haplotype needs to be determined in a database search. In order to improve the collection of mtDNA lineages from the Iberian and South American subcontinents, we here report the results of a collaborative study involving nine laboratories from the Spanish and Portuguese Speaking Working Group of the International Society for Forensic Genetics (GHEP-ISFG) and EMPOP. The individual laboratories contributed population data that were generated throughout the past 10 years, but in the majority of cases have not been made available to the scientific community. A total of 1019 haplotypes from Iberia (Basque Country, 2 general Spanish populations, 2 North and 1 Central Portugal populations), and Latin America (3 populations from São Paulo) were collected, reviewed and harmonized according to defined EMPOP criteria. The majority of data ambiguities that were found during the reviewing process (41 in total) were transcription errors confirming that the documentation process is still the most error-prone stage in reporting mtDNA population data, especially when performed manually. This GHEP–EMPOP collaboration has significantly improved the quality of the individual mtDNA datasets and adds mtDNA population data as valuable resource to the EMPOP database (www.empop.org). PMID:21075696

DNA Barcodes for Forensically Important Fly Species in Brazil.

PubMed

Koroiva, Ricardo; de Souza, Mirian S; Roque, Fabio de Oliveira; Pepinelli, Mateus

2018-04-07

Here, we analyze 248 DNA barcode sequences of 35 fly species of forensic importance in Brazil. DNA barcoding can be effectively used for specimen identification of these species, allowing the unambiguous identification of 31 species, an overall success rate of 88%. Our results show a high rate of success for molecular identification using DNA barcoding sequences and open new perspectives for immature species identification, a subject on which limited forensic investigations exist in Tropical regions. We also address the implications of building a robust forensic DNA barcode database. A geographic bias is recognized for the COI dataset available for forensically important fly species in Brazil, with concentration of sequences from specimens collected mainly in sites located in the Cerrado, Mata Atlântica, and Pampa biomes.

Overview of Forensic Toxicology, Yesterday, Today and in the Future.

PubMed

Chung, Heesun; Choe, Sanggil

2017-01-01

The scope of forensic toxicology has been tremendously expanded over the past 50 years. From two general sections forensic toxicology can be further classified into 8-9 sections. The most outstanding improvement in forensic toxicology is the changes brought by instrumental development. The field of forensic toxicology was revolutionized by the development of immunoassay and benchtop GC-MS in the 1980's and LC-MS-MS in 2000's. Detection of trace amounts of analytes has allowed the use of new specimens such as hair and oral fluids, along with blood and urine. Over a longer period of time, continuous efforts have been made to efficiently extract and separate drug and poison from biological fluids. International endeavors to develop high quality standards and guidelines for drugs and poisons in biological specimens and to promote them in order to increase reliability of laboratories are also part of the recent advancement of forensic toxicology. Interpretation of postmortem toxicology encompasses various factors including postmortem redistribution and stability. Considering the recent trend, the interpretation of toxicological results should account for autopsy findings, crime scene information, and related medical history. The fields of forensic toxicology will continuously develop to improve analysis of target analytes from various specimens, quality assurance program, and results interpretation. In addition, the development of analytical techniques will also contribute further advancement of forensic toxicology. The societies of forensic toxicologists, such as TIAFT, will play an important role for the advancement of forensic toxicology by collaborating and sharing ideas between toxicologists from both developed and developing countries. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

Applicability of the ParaDNA(®) Screening System to Seminal Samples.

PubMed

Tribble, Nicholas D; Miller, Jamie A D; Dawnay, Nick; Duxbury, Nicola J

2015-05-01

Seminal fluid represents a common biological material recovered from sexual assault crime scenes. Such samples can be prescreened using different techniques to determine cell type and relative amount before submitting for full STR profiling. The ParaDNA(®) Screening System is a novel forensic test which identifies the presence of DNA through amplification and detection of two common STR loci (D16S539 and TH01) and the Amelogenin marker. The detection of the Y allele in samples could provide a useful tool in the triage and submission of sexual assault samples by enforcement authorities. Male template material was detected on a range of common sexual assault evidence items including cotton pillow cases, condoms, swab heads and glass surfaces and shows a detection limit of 1 in 1000 dilution of neat semen. These data indicate this technology has the potential to be a useful tool for the detection of male donor DNA in sexual assault casework. © 2015 American Academy of Forensic Sciences.

Comparing the Scoring of Human Decomposition from Digital Images to Scoring Using On-site Observations.

PubMed

Dabbs, Gretchen R; Bytheway, Joan A; Connor, Melissa

2017-09-01

When in forensic casework or empirical research in-person assessment of human decomposition is not possible, the sensible substitution is color photographic images. To date, no research has confirmed the utility of color photographic images as a proxy for in situ observation of the level of decomposition. Sixteen observers scored photographs of 13 human cadavers in varying decomposition stages (PMI 2-186 days) using the Total Body Score system (total n = 929 observations). The on-site TBS was compared with recorded observations from digital color images using a paired samples t-test. The average difference between on-site and photographic observations was -0.20 (t = -1.679, df = 928, p = 0.094). Individually, only two observers, both students with <1 year of experience, demonstrated TBS statistically significantly different than the on-site value, suggesting that with experience, observations of human decomposition based on digital images can be substituted for assessments based on observation of the corpse in situ, when necessary. © 2017 American Academy of Forensic Sciences.

DNA methylation: the future of crime scene investigation?

PubMed

Gršković, Branka; Zrnec, Dario; Vicković, Sanja; Popović, Maja; Mršić, Gordan

2013-07-01

Proper detection and subsequent analysis of biological evidence is crucial for crime scene reconstruction. The number of different criminal acts is increasing rapidly. Therefore, forensic geneticists are constantly on the battlefield, trying hard to find solutions how to solve them. One of the essential defensive lines in the fight against the invasion of crime is relying on DNA methylation. In this review, the role of DNA methylation in body fluid identification and other DNA methylation applications are discussed. Among other applications of DNA methylation, age determination of the donor of biological evidence, analysis of the parent-of-origin specific DNA methylation markers at imprinted loci for parentage testing and personal identification, differentiation between monozygotic twins due to their different DNA methylation patterns, artificial DNA detection and analyses of DNA methylation patterns in the promoter regions of circadian clock genes are the most important ones. Nevertheless, there are still a lot of open chapters in DNA methylation research that need to be closed before its final implementation in routine forensic casework.

Integrated computer-aided forensic case analysis, presentation, and documentation based on multimodal 3D data.

PubMed

Bornik, Alexander; Urschler, Martin; Schmalstieg, Dieter; Bischof, Horst; Krauskopf, Astrid; Schwark, Thorsten; Scheurer, Eva; Yen, Kathrin

2018-06-01

Three-dimensional (3D) crime scene documentation using 3D scanners and medical imaging modalities like computed tomography (CT) and magnetic resonance imaging (MRI) are increasingly applied in forensic casework. Together with digital photography, these modalities enable comprehensive and non-invasive recording of forensically relevant information regarding injuries/pathologies inside the body and on its surface. Furthermore, it is possible to capture traces and items at crime scenes. Such digitally secured evidence has the potential to similarly increase case understanding by forensic experts and non-experts in court. Unlike photographs and 3D surface models, images from CT and MRI are not self-explanatory. Their interpretation and understanding requires radiological knowledge. Findings in tomography data must not only be revealed, but should also be jointly studied with all the 2D and 3D data available in order to clarify spatial interrelations and to optimally exploit the data at hand. This is technically challenging due to the heterogeneous data representations including volumetric data, polygonal 3D models, and images. This paper presents a novel computer-aided forensic toolbox providing tools to support the analysis, documentation, annotation, and illustration of forensic cases using heterogeneous digital data. Conjoint visualization of data from different modalities in their native form and efficient tools to visually extract and emphasize findings help experts to reveal unrecognized correlations and thereby enhance their case understanding. Moreover, the 3D case illustrations created for case analysis represent an efficient means to convey the insights gained from case analysis to forensic non-experts involved in court proceedings like jurists and laymen. The capability of the presented approach in the context of case analysis, its potential to speed up legal procedures and to ultimately enhance legal certainty is demonstrated by introducing a number of representative forensic cases. Copyright © 2018 The Author(s). Published by Elsevier B.V. All rights reserved.

Hair Analysis in Forensic Toxicology: An Updated Review with a Special Focus on Pitfalls.

PubMed

Kintz, Pascal

2017-01-01

The detection of drugs in hair analysis has progressively emerged as a consequence of the enhanced sensitivity of analytical techniques used in forensic toxicology; a greater advantage in using this matrix with respect to classical ones (i.e. urine and blood) is an easier and non-invasive sample collection, even when the careful supervision of law enforcement officers is required to avoid the risk that the sample may be adulterated or replaced. Moreover, according to the length of the hair, the history of drug exposure can be retrospectively monitored from few weeks up to months or years since sample collection. Through a detailed revision of the existent literature, this manuscript provides information on the proper sample collection, preparation and analysis, as well as pitfalls in forensic hair analysis, and summarizes the wide range of application of this technology, including excessive alcohol drinking, doping, child abuse, and offences linked to drug use. Verification of history of psychotropic drugs, alcohol and doping agents use by hair analysis, hair testing for driving license regranting and drug facilitated crimes, and testing for drugs in hair of children have been reviewed together with recent trends in hair contamination and possibility to disclose use of new psychoactive substances by hair analysis. Hair analysis in forensic toxicology has been quickly emerged and improved in recent years; a deeper knowledge of advantages and limitations of this unique matrix is necessary for a better use in forensic caseworks. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

Development of an Italian RM Y-STR haplotype database: Results of the 2013 GEFI collaborative exercise.

PubMed

Robino, C; Ralf, A; Pasino, S; De Marchi, M R; Ballantyne, K N; Barbaro, A; Bini, C; Carnevali, E; Casarino, L; Di Gaetano, C; Fabbri, M; Ferri, G; Giardina, E; Gonzalez, A; Matullo, G; Nutini, A L; Onofri, V; Piccinini, A; Piglionica, M; Ponzano, E; Previderè, C; Resta, N; Scarnicci, F; Seidita, G; Sorçaburu-Cigliero, S; Turrina, S; Verzeletti, A; Kayser, M

2015-03-01

Recently introduced rapidly mutating Y-chromosomal short tandem repeat (RM Y-STR) loci, displaying a multiple-fold higher mutation rate relative to any other Y-STRs, including those conventionally used in forensic casework, have been demonstrated to improve the resolution of male lineage differentiation and to allow male relative separation usually impossible with standard Y-STRs. However, large and geographically-detailed frequency haplotype databases are required to estimate the statistical weight of RM Y-STR haplotype matches if observed in forensic casework. With this in mind, the Italian Working Group (GEFI) of the International Society for Forensic Genetics launched a collaborative exercise aimed at generating an Italian quality controlled forensic RM Y-STR haplotype database. Overall 1509 male individuals from 13 regional populations covering northern, central and southern areas of the Italian peninsula plus Sicily were collected, including both "rural" and "urban" samples classified according to population density in the sampling area. A subset of individuals was additionally genotyped for Y-STR loci included in the Yfiler and PowerPlex Y23 (PPY23) systems (75% and 62%, respectively), allowing the comparison of RM and conventional Y-STRs. Considering the whole set of 13 RM Y-STRs, 1501 unique haplotypes were observed among the 1509 sampled Italian men with a haplotype diversity of 0.999996, largely superior to Yfiler and PPY23 with 0.999914 and 0.999950, respectively. AMOVA indicated that 99.996% of the haplotype variation was within populations, confirming that genetic-geographic structure is almost undetected by RM Y-STRs. Haplotype sharing among regional Italian populations was not observed at all with the complete set of 13 RM Y-STRs. Haplotype sharing within Italian populations was very rare (0.27% non-unique haplotypes), and lower in urban (0.22%) than rural (0.29%) areas. Additionally, 422 father-son pairs were investigated, and 20.1% of them could be discriminated by the whole set of 13 RM Y-STRs, which was very close to the theoretically expected estimate of 19.5% given the mutation rates of the markers used. Results obtained from a high-coverage Italian haplotype dataset confirm on the regional scale the exceptional ability of RM Y-STRs to resolve male lineages previously observed globally, and attest the unsurpassed value of RM Y-STRs for male-relative differentiation purposes. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

Molecular identification of python species: development and validation of a novel assay for forensic investigations.

PubMed

Ciavaglia, Sherryn A; Tobe, Shanan S; Donnellan, Stephen C; Henry, Julianne M; Linacre, Adrian M T

2015-05-01

Python snake species are often encountered in illegal activities and the question of species identity can be pertinent to such criminal investigations. Morphological identification of species of pythons can be confounded by many issues and molecular examination by DNA analysis can provide an alternative and objective means of identification. Our paper reports on the development and validation of a PCR primer pair that amplifies a segment of the mitochondrial cytochrome b gene that has been suggested previously as a good candidate locus for differentiating python species. We used this DNA region to perform species identification of pythons, even when the template DNA was of poor quality, as might be the case with forensic evidentiary items. Validation tests are presented to demonstrate the characteristics of the assay. Tests involved the cross-species amplification of this marker in non-target species, minimum amount of DNA template required, effects of degradation on product amplification and a blind trial to simulate a casework scenario that provided 100% correct identity. Our results demonstrate that this assay performs reliably and robustly on pythons and can be applied directly to forensic investigations where the presence of a species of python is in question. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

The Use of Laser Microdissection in Forensic Sexual Assault Casework: Pros and Cons Compared to Standard Methods.

PubMed

Costa, Sergio; Correia-de-Sá, Paulo; Porto, Maria J; Cainé, Laura

2017-07-01

Sexual assault samples are among the most frequently analyzed in a forensic laboratory. These account for almost half of all samples processed routinely, and a large portion of these cases remain unsolved. These samples often pose problems to traditional analytic methods of identification because they consist most frequently of cell mixtures from at least two contributors: the victim (usually female) and the perpetrator (usually male). In this study, we propose the use of current preliminary testing for sperm detection in order to determine the chances of success when faced with samples which can be good candidates to undergo analysis with the laser microdissection technology. Also, we used laser microdissection technology to capture fluorescently stained cells of interest differentiated by gender. Collected materials were then used for DNA genotyping with commercially available amplification kits such as Minifiler, Identifiler Plus, NGM, and Y-Filer. Both the methodology and the quality of the results were evaluated to assess the pros and cons of laser microdissection compared with standard methods. Overall, the combination of fluorescent staining combined with the Minifiler amplification kit provided the best results for autosomal markers, whereas the Y-Filer kit returned the expected results regardless of the used method. © 2017 American Academy of Forensic Sciences.

DNA testing in homicide investigations.

PubMed

Prahlow, Joseph A; Cameron, Thomas; Arendt, Alexander; Cornelis, Kenneth; Bontrager, Anthony; Suth, Michael S; Black, Lisa; Tobey, Rebbecca; Pollock, Sharon; Stur, Shawn; Cotter, Kenneth; Gabrielse, Joel

2017-10-01

Objectives With the widespread use of DNA testing, police, death investigators, and attorneys need to be aware of the capabilities of this technology. This review provides an overview of scenarios where DNA evidence has played a major role in homicide investigations in order to highlight important educational issues for police, death investigators, forensic pathologists, and attorneys. Methods This was a nonrandom, observational, retrospective study. Data were obtained from the collective files of the authors from casework during a 15-year period, from 2000 through 2014. Results A series of nine scenarios, encompassing 11 deaths, is presented from the standpoint of the police and death investigation, the forensic pathology autopsy performance, the subsequent DNA testing of evidence, and, ultimately, the final adjudication of cases. Details of each case are presented, along with a discussion that focuses on important aspects of sample collection for potential DNA testing, especially at the crime scene and the autopsy. The presentation highlights the diversity of case and evidence types in which DNA testing played a valuable role in the successful prosecution of the case. Conclusions By highlighting homicides where DNA testing contributed to the successful adjudication of cases, police, death investigators, forensic pathologists, and attorneys will be better informed regarding the types of evidence and situations where such testing is of potential value.

Accuracy and reliability of forensic latent fingerprint decisions

PubMed Central

Ulery, Bradford T.; Hicklin, R. Austin; Buscaglia, JoAnn; Roberts, Maria Antonia

2011-01-01

The interpretation of forensic fingerprint evidence relies on the expertise of latent print examiners. The National Research Council of the National Academies and the legal and forensic sciences communities have called for research to measure the accuracy and reliability of latent print examiners’ decisions, a challenging and complex problem in need of systematic analysis. Our research is focused on the development of empirical approaches to studying this problem. Here, we report on the first large-scale study of the accuracy and reliability of latent print examiners’ decisions, in which 169 latent print examiners each compared approximately 100 pairs of latent and exemplar fingerprints from a pool of 744 pairs. The fingerprints were selected to include a range of attributes and quality encountered in forensic casework, and to be comparable to searches of an automated fingerprint identification system containing more than 58 million subjects. This study evaluated examiners on key decision points in the fingerprint examination process; procedures used operationally include additional safeguards designed to minimize errors. Five examiners made false positive errors for an overall false positive rate of 0.1%. Eighty-five percent of examiners made at least one false negative error for an overall false negative rate of 7.5%. Independent examination of the same comparisons by different participants (analogous to blind verification) was found to detect all false positive errors and the majority of false negative errors in this study. Examiners frequently differed on whether fingerprints were suitable for reaching a conclusion. PMID:21518906

Genetic structure and forensic parameters of 38 Indels for human identification purposes in eight Mexican populations.

PubMed

Martínez-Cortés, G; Gusmão, L; Pereira, R; Salcido, V H; Favela-Mendoza, A F; Muñoz-Valle, J F; Inclán-Sánchez, A; López-Hernández, L B; Rangel-Villalobos, H

2015-07-01

Insertion-deletions for human identification purposes (HID-Indels) offer advantages to solve particular forensic situations and complex paternity cases. In Mexico, admixed population known as Mestizos is the largest (∼90%), plus a number of Amerindian groups (∼10%), which have not been studied with HID-Indels. For this reason, allele frequencies and forensic parameters for 38 HID-Indels were estimated in 531 unrelated individuals from one Amerindian (Purépecha) and seven Mestizo populations from different regions of the country. Genotype distribution was in agreement with Hardy-Weinberg expectations in almost all loci/populations. The linkage disequilibrium (LD) test did not reveal possible associations between loci pairs in all eight Mexican populations. The combined power of discrimination was high in all populations (PD >99.99999999998%). However, the power of exclusion of the 38 HID-Indel system (PE >99.6863%) was reduced regarding most of autosomal STR kits. The assessment of genetic structure (AMOVA) and relationships between populations (FST) demonstrated significant differences among Mexican populations, mainly of the Purépecha Amerindian group. Among Mexican-Mestizos, three population clusters consistent with geography were defined: (i) North-West region: Chihuahua, Sinaloa, and Jalisco; (ii) Central-Southern region: Mexico City, Veracruz and Yucatan; (iii) South region: Chiapas. In brief, this report validates the inclusion of the 38 HID-Indel system in forensic casework and paternity cases in seven Mexican-Mestizo populations from different regions, and in one Mexican Amerindian group. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Genotyping of 75 SNPs using arrays for individual identification in five population groups.

PubMed

Hwa, Hsiao-Lin; Wu, Lawrence Shih Hsin; Lin, Chun-Yen; Huang, Tsun-Ying; Yin, Hsiang-I; Tseng, Li-Hui; Lee, James Chun-I

2016-01-01

Single nucleotide polymorphism (SNP) typing offers promise to forensic genetics. Various strategies and panels for analyzing SNP markers for individual identification have been published. However, the best panels with fewer identity SNPs for all major population groups are still under discussion. This study aimed to find more autosomal SNPs with high heterozygosity for individual identification among Asian populations. Ninety-six autosomal SNPs of 502 DNA samples from unrelated individuals of five population groups (208 Taiwanese Han, 83 Filipinos, 62 Thais, 69 Indonesians, and 80 individuals with European, Near Eastern, or South Asian ancestry) were analyzed using arrays in an initial screening, and 75 SNPs (group A, 46 newly selected SNPs; groups B, 29 SNPs based on a previous SNP panel) were selected for further statistical analyses. Some SNPs with high heterozygosity from Asian populations were identified. The combined random match probability of the best 40 and 45 SNPs was between 3.16 × 10(-17) and 7.75 × 10(-17) and between 2.33 × 10(-19) and 7.00 × 10(-19), respectively, in all five populations. These loci offer comparable power to short tandem repeats (STRs) for routine forensic profiling. In this study, we demonstrated the population genetic characteristics and forensic parameters of 75 SNPs with high heterozygosity from five population groups. This SNPs panel can provide valuable genotypic information and can be helpful in forensic casework for individual identification among these populations.

Accuracy and reliability of forensic latent fingerprint decisions.

PubMed

Ulery, Bradford T; Hicklin, R Austin; Buscaglia, Joann; Roberts, Maria Antonia

2011-05-10

The interpretation of forensic fingerprint evidence relies on the expertise of latent print examiners. The National Research Council of the National Academies and the legal and forensic sciences communities have called for research to measure the accuracy and reliability of latent print examiners' decisions, a challenging and complex problem in need of systematic analysis. Our research is focused on the development of empirical approaches to studying this problem. Here, we report on the first large-scale study of the accuracy and reliability of latent print examiners' decisions, in which 169 latent print examiners each compared approximately 100 pairs of latent and exemplar fingerprints from a pool of 744 pairs. The fingerprints were selected to include a range of attributes and quality encountered in forensic casework, and to be comparable to searches of an automated fingerprint identification system containing more than 58 million subjects. This study evaluated examiners on key decision points in the fingerprint examination process; procedures used operationally include additional safeguards designed to minimize errors. Five examiners made false positive errors for an overall false positive rate of 0.1%. Eighty-five percent of examiners made at least one false negative error for an overall false negative rate of 7.5%. Independent examination of the same comparisons by different participants (analogous to blind verification) was found to detect all false positive errors and the majority of false negative errors in this study. Examiners frequently differed on whether fingerprints were suitable for reaching a conclusion.

Archive of mass spectral data files on recordable CD-ROMs and creation and maintenance of a searchable computerized database.

PubMed

Amick, G D

1999-01-01

A database containing names of mass spectral data files generated in a forensic toxicology laboratory and two Microsoft Visual Basic programs to maintain and search this database is described. The data files (approximately 0.5 KB/each) were collected from six mass spectrometers during routine casework. Data files were archived on 650 MB (74 min) recordable CD-ROMs. Each recordable CD-ROM was given a unique name, and its list of data file names was placed into the database. The present manuscript describes the use of search and maintenance programs for searching and routine upkeep of the database and creation of CD-ROMs for archiving of data files.

Child Welfare Caseworker Education and Caregiver Behavioral Service Use and Satisfaction with the Caseworker.

PubMed

Staudt, Marlys; Jolles, Mónica Pérez; Chuang, Emmeline; Wells, Rebecca

2015-01-01

Social work has long been identified with child welfare, and research has generally found that child welfare caseworkers with a social work degree are better prepared than aseworkers with other degrees. Little knowledge exists though about the relationship between caseworker professional background and caregiver behavioral health service use or their satisfaction with the caseworker. Using data from the National Survey of Child and Adolescent Well-Being, we found no significant relationships between having a social work degree and caregiver use of services or satisfaction with the caseworker. More research is needed to clarify how caseworker characteristics, including professional preparation, influence child welfare outcomes.

Establishing a novel automated magnetic bead-based method for the extraction of DNA from a variety of forensic samples.

PubMed

Witt, Sebastian; Neumann, Jan; Zierdt, Holger; Gébel, Gabriella; Röscheisen, Christiane

2012-09-01

Automated systems have been increasingly utilized for DNA extraction by many forensic laboratories to handle growing numbers of forensic casework samples while minimizing the risk of human errors and assuring high reproducibility. The step towards automation however is not easy: The automated extraction method has to be very versatile to reliably prepare high yields of pure genomic DNA from a broad variety of sample types on different carrier materials. To prevent possible cross-contamination of samples or the loss of DNA, the components of the kit have to be designed in a way that allows for the automated handling of the samples with no manual intervention necessary. DNA extraction using paramagnetic particles coated with a DNA-binding surface is predestined for an automated approach. For this study, we tested different DNA extraction kits using DNA-binding paramagnetic particles with regard to DNA yield and handling by a Freedom EVO(®)150 extraction robot (Tecan) equipped with a Te-MagS magnetic separator. Among others, the extraction kits tested were the ChargeSwitch(®)Forensic DNA Purification Kit (Invitrogen), the PrepFiler™Automated Forensic DNA Extraction Kit (Applied Biosystems) and NucleoMag™96 Trace (Macherey-Nagel). After an extensive test phase, we established a novel magnetic bead extraction method based upon the NucleoMag™ extraction kit (Macherey-Nagel). The new method is readily automatable and produces high yields of DNA from different sample types (blood, saliva, sperm, contact stains) on various substrates (filter paper, swabs, cigarette butts) with no evidence of a loss of magnetic beads or sample cross-contamination. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

Euclidean Distances as measures of speaker similarity including identical twin pairs: A forensic investigation using source and filter voice characteristics.

PubMed

San Segundo, Eugenia; Tsanas, Athanasios; Gómez-Vilda, Pedro

2017-01-01

There is a growing consensus that hybrid approaches are necessary for successful speaker characterization in Forensic Speaker Comparison (FSC); hence this study explores the forensic potential of voice features combining source and filter characteristics. The former relate to the action of the vocal folds while the latter reflect the geometry of the speaker's vocal tract. This set of features have been extracted from pause fillers, which are long enough for robust feature estimation while spontaneous enough to be extracted from voice samples in real forensic casework. Speaker similarity was measured using standardized Euclidean Distances (ED) between pairs of speakers: 54 different-speaker (DS) comparisons, 54 same-speaker (SS) comparisons and 12 comparisons between monozygotic twins (MZ). Results revealed that the differences between DS and SS comparisons were significant in both high quality and telephone-filtered recordings, with no false rejections and limited false acceptances; this finding suggests that this set of voice features is highly speaker-dependent and therefore forensically useful. Mean ED for MZ pairs lies between the average ED for SS comparisons and DS comparisons, as expected according to the literature on twin voices. Specific cases of MZ speakers with very high ED (i.e. strong dissimilarity) are discussed in the context of sociophonetic and twin studies. A preliminary simplification of the Vocal Profile Analysis (VPA) Scheme is proposed, which enables the quantification of voice quality features in the perceptual assessment of speaker similarity, and allows for the calculation of perceptual-acoustic correlations. The adequacy of z-score normalization for this study is also discussed, as well as the relevance of heat maps for detecting the so-called phantoms in recent approaches to the biometric menagerie. Copyright © 2016 The Authors. Published by Elsevier B.V. All rights reserved.

Comprehensive annotated STR physical map of the human Y chromosome: Forensic implications.

PubMed

Hanson, Erin K; Ballantyne, Jack

2006-03-01

A plethora of Y-STR markers from diverse sources have been deposited in public databases and represent potential candidates for incorporation into the next generation of Y-STR multiplexes for forensic use. Here, based upon all of the Y-STR loci that have been deposited in the human genome database (>400), we have sequentially positioned each one along the Y chromosome using the most current human genome sequencing data (NCBI Build 35). The information derived from this work defines the number and relative position of all potentially forensically relevant Y-STR loci, their location within the physical linkage map of the Y chromosome and their relationship to structural genes. We conclude that there exists at present at least 417 separate Y-STR markers available for potential forensic use, although many of these will be found to be unsuitable for other reasons. However, from this data, we were able to identify 28 pairs of duplicated loci that were given separate DYS designations and four pairs of loci with overlapping flanking regions. Removing one locus from each set of duplicates reduced the number of potentially useful loci from 417 to 389. The derived information should be useful for workers who are designing novel Y-STR multiplexes to ensure the presence of non-synonymous loci and, if so desired, to avoid loci that lie within structural genes. It may also be useful for forensic casework practitioners (or molecular anthropologists) to aid in distinguishing between chromosomal rearrangements (such as duplications and deletions) and bona fide DNA admixtures or null alleles caused by primer binding site mutations. We illustrate the practical usefulness of the chromosomal positioning data in the design of eight multiplex systems using 94 Y-STR loci.

A Generalized Approach to Forensic Dye Identification: Development and Utility of Reference Libraries.

PubMed

Groves, Ethan; Palenik, Skip; Palenik, Christopher S

2018-04-18

While color is arguably the most important optical property of evidential fibers, the actual dyestuffs responsible for its expression in them are, in forensic trace evidence examinations, rarely analyzed and still less often identified. This is due, primarily, to the exceedingly small quantities of dye present in a single fiber as well as to the fact that dye identification is a challenging analytical problem, even when large quantities are available for analysis. Among the practical reasons for this are the wide range of dyestuffs available (and the even larger number of trade names), the low total concentration of dyes in the finished product, the limited amount of sample typically available for analysis in forensic cases, and the complexity of the dye mixtures that may exist within a single fiber. Literature on the topic of dye analysis is often limited to a specific method, subset of dyestuffs, or an approach that is not applicable given the constraints of a forensic analysis. Here, we present a generalized approach to dye identification that ( 1 ) combines several robust analytical methods, ( 2 ) is broadly applicable to a wide range of dye chemistries, application classes, and fiber types, and ( 3 ) can be scaled down to forensic casework-sized samples. The approach is based on the development of a reference collection of 300 commercially relevant textile dyes that have been characterized by a variety of microanalytical methods (HPTLC, Raman microspectroscopy, infrared microspectroscopy, UV-Vis spectroscopy, and visible microspectrophotometry). Although there is no single approach that is applicable to all dyes on every type of fiber, a combination of these analytical methods has been applied using a reproducible approach that permits the use of reference libraries to constrain the identity of and, in many cases, identify the dye (or dyes) present in a textile fiber sample.

Validity and reliability of dental age estimation of teeth root translucency based on digital luminance determination.

PubMed

Ramsthaler, Frank; Kettner, Mattias; Verhoff, Marcel A

2014-01-01

In forensic anthropological casework, estimating age-at-death is key to profiling unknown skeletal remains. The aim of this study was to examine the reliability of a new, simple, fast, and inexpensive digital odontological method for age-at-death estimation. The method is based on the original Lamendin method, which is a widely used technique in the repertoire of odontological aging methods in forensic anthropology. We examined 129 single root teeth employing a digital camera and imaging software for the measurement of the luminance of the teeth's translucent root zone. Variability in luminance detection was evaluated using statistical technical error of measurement analysis. The method revealed stable values largely unrelated to observer experience, whereas requisite formulas proved to be camera-specific and should therefore be generated for an individual recording setting based on samples of known chronological age. Multiple regression analysis showed a highly significant influence of the coefficients of the variables "arithmetic mean" and "standard deviation" of luminance for the regression formula. For the use of this primer multivariate equation for age-at-death estimation in casework, a standard error of the estimate of 6.51 years was calculated. Step-by-step reduction of the number of embedded variables to linear regression analysis employing the best contributor "arithmetic mean" of luminance yielded a regression equation with a standard error of 6.72 years (p < 0.001). The results of this study not only support the premise of root translucency as an age-related phenomenon, but also demonstrate that translucency reflects a number of other influencing factors in addition to age. This new digital measuring technique of the zone of dental root luminance can broaden the array of methods available for estimating chronological age, and furthermore facilitate measurement and age classification due to its low dependence on observer experience.

Ethical, legal and social implications of forensic molecular phenotyping in South Africa.

PubMed

Slabbert, Nandi; Heathfield, Laura Jane

2018-06-01

Conventional forensic DNA analysis involves a matching principle, which compares DNA profiles from evidential samples to those from reference samples of known origin. In casework, however, the accessibility to a reference sample is not guaranteed which limits the use of DNA as an investigative tool. This has led to the development of phenotype prediction, which uses SNP analysis to estimate the physical appearance of the sample donor. Physical traits, such as eye, hair and skin colour, have been associated with certain alleles within specific genes involved in the melanogenesis pathways. These genetic markers are also associated with ancestry and their trait prediction ability has mainly been assessed in European and North American populations. This has prompted research investigating the discriminatory power of these markers in other populations, especially those exhibiting admixture. South Africa is well known for its diversity, and the viability of these particular SNPs still needs to be assessed within this population. South African law currently restricts the use of DNA for molecular phenotyping, and there are also numerous ethical and social considerations, all of which are discussed. © 2018 John Wiley & Sons Ltd.

Fibers under fire: suggestions for improving their use to provide forensic evidence.

PubMed

Grieve, M C; Wiggins, K G

2001-07-01

The current emphasis on DNA technology in forensic science has led many to believe that trace evidence examinations, including fibers, may be of little value. Reasons are given here to show that this is an erroneous assumption. In the face of this situation, fibers examiners have been challenged to consider ways in which they can improve the services they offer to the Criminal Justice System not only by increasing the efficiency of the examinations, but also by expressing the evidential value of the findings in a clearer way. The separate stages within fibers casework from evidence collection to report writing are critically examined. Suggestions are made on how improvements may be achieved. Areas where particular progress can be made include improving communication and exchange of information between the investigator and the scientist and streamlining analysis by using the latest equipment in conjunction with effective case management. In addition, ways of making better use of existing data pertaining to fiber frequencies, accumulating new data by using the resources of working groups, and improving training procedures with respect to evidence interpretation are discussed.

Tumoural specimens for forensic purposes: comparison of genetic alterations in frozen and formalin-fixed paraffin-embedded tissues.

PubMed

Ananian, Viviana; Tozzo, Pamela; Ponzano, Elena; Nitti, Donato; Rodriguez, Daniele; Caenazzo, Luciana

2011-05-01

In certain circumstances, tumour tissue specimens are the only DNA resource available for forensic DNA analysis. However, cancer tissues can show microsatellite instability and loss of heterozygosity which, if concerning the short tandem repeats (STRs) used in the forensic field, can cause misinterpretation of the results. Moreover, though formalin-fixed paraffin-embedded tissues (FFPET) represent a large resource for these analyses, the quality of the DNA obtained from this kind of specimen can be an important limit. In this study, we evaluated the use of tumoural tissue as biological material for the determination of genetic profiles in the forensic field, highlighting which STR polymorphisms are more susceptible to tumour genetic alterations and which of the analysed tumours show a higher genetic variability. The analyses were conducted on samples of the same tissues conserved in different storage conditions, to compare genetic profiles obtained by frozen tissues and formalin-fixed paraffin-embedded tissues. The importance of this study is due to the large number of specimens analysed (122), the large number of polymorphisms analysed for each specimen (39), and the possibility to compare, many years after storage, the same tissue frozen and formalin-fixed paraffin-embedded. In the comparison between the genetic profiles of frozen tumour tissues and FFPET, the same genetic alterations have been reported in both kinds of specimens. However, FFPET showed new alterations. We conclude that the use of FFPET requires greater attention than frozen tissues in the results interpretation and great care in both pre-extraction and extraction processes.

Testing inter-observer reliability of the Transition Analysis aging method on the William M. Bass forensic skeletal collection.

PubMed

Fojas, Christina L; Kim, Jieun; Minsky-Rowland, Jocelyn D; Algee-Hewitt, Bridget F B

2018-01-01

Skeletal age estimation is an integral part of the biological profile. Recent work shows how multiple-trait approaches better capture senescence as it occurs at different rates among individuals. Furthermore, a Bayesian statistical framework of analysis provides more useful age estimates. The component-scoring method of Transition Analysis (TA) may resolve many of the functional and statistical limitations of traditional phase-aging methods and is applicable to both paleodemography and forensic casework. The present study contributes to TA-research by validating TA for multiple, differently experienced observers using a collection of modern forensic skeletal cases. Five researchers independently applied TA to a random sample of 58 documented individuals from the William M. Bass Forensic Skeletal Collection, for whom knowledge of chronological age was withheld. Resulting scores were input into the ADBOU software and maximum likelihood estimates (MLEs) and 95% confidence intervals (CIs) were produced using the forensic prior. Krippendorff's alpha was used to evaluate interrater reliability and agreement. Inaccuracy and bias were measured to gauge the magnitude and direction of difference between estimated ages and chronological ages among the five observers. The majority of traits had moderate to excellent agreement among observers (≥0.6). The superior surface morphology had the least congruence (0.4), while the ventral symphyseal margin had the most (0.9) among scores. Inaccuracy was the lowest for individuals younger than 30 and the greatest for individuals over 60. Consistent over-estimation of individuals younger than 30 and under-estimation of individuals over 40 years old occurred. Individuals in their 30s showed a mixed pattern of under- and over-estimation among observers. These results support the use of the TA method by researchers of varying experience levels. Further, they validate its use on forensic cases, given the low error overall. © 2017 Wiley Periodicals, Inc.

Forensic Toxicology: An Introduction.

PubMed

Smith, Michael P; Bluth, Martin H

2016-12-01

This article presents an overview of forensic toxicology. The authors describe the three components that make up forensic toxicology: workplace drug testing, postmortem toxicology, and human performance toxicology. Also discussed are the specimens that are tested, the methods used, and how the results are interpreted in this particular discipline. Copyright © 2016 Elsevier Inc. All rights reserved.

Forensic-paternity effectiveness and genetics population analysis of six non-CODIS mini-STR loci (D1S1656, D2S441, D6S1043, D10S1248, D12S391, D22S1045) and SE33 in Mestizo and Amerindian populations from Mexico.

PubMed

Burguete-Argueta, Nelsi; Martínez De la Cruz, Braulio; Camacho-Mejorado, Rafael; Santana, Carla; Noris, Gino; López-Bayghen, Esther; Arellano-Galindo, José; Majluf-Cruz, Abraham; Antonio Meraz-Ríos, Marco; Gómez, Rocío

2016-11-01

STRs are powerful tools intensively used in forensic and kinship studies. In order to assess the effectiveness of non-CODIS genetic markers in forensic and paternity tests, the genetic composition of six mini short tandem repeats-mini-STRs-(D1S1656, D2S441, D6S1043, D10S1248, D12S391, D22S1045) and the microsatellite SE33 in Mestizo and Amerindian populations from Mexico were studied. Using multiplex polymerase chain reactions and capillary electrophoresis, this study genotyped all loci from 870 chromosomes and evaluated the statistical genetic parameters. All mini-STRs studied were in agreement with HW and linkage equilibrium; however, an important HW departure for SE33 was found in the Mestizo population (p ≤ 0.0001). Regarding paternity and forensic statistical parameters, high values of combined power discrimination and mean power of exclusion were found using these seven markers. The principal co-ordinate analysis based on allele frequencies of three mini-STRs showed the complex genetic architecture of the Mestizo population. The results indicate that this set of loci is suitable to genetically identify individuals in the Mexican population, supporting its effectiveness in human identification casework. In addition, these findings add new statistical values and emphasise the importance of the use of non-CODIS markers in complex populations in order to avoid erroneous assumptions.

Authentication of forensic DNA samples.

PubMed

Frumkin, Dan; Wasserstrom, Adam; Davidson, Ariane; Grafit, Arnon

2010-02-01

Over the past twenty years, DNA analysis has revolutionized forensic science, and has become a dominant tool in law enforcement. Today, DNA evidence is key to the conviction or exoneration of suspects of various types of crime, from theft to rape and murder. However, the disturbing possibility that DNA evidence can be faked has been overlooked. It turns out that standard molecular biology techniques such as PCR, molecular cloning, and recently developed whole genome amplification (WGA), enable anyone with basic equipment and know-how to produce practically unlimited amounts of in vitro synthesized (artificial) DNA with any desired genetic profile. This artificial DNA can then be applied to surfaces of objects or incorporated into genuine human tissues and planted in crime scenes. Here we show that the current forensic procedure fails to distinguish between such samples of blood, saliva, and touched surfaces with artificial DNA, and corresponding samples with in vivo generated (natural) DNA. Furthermore, genotyping of both artificial and natural samples with Profiler Plus((R)) yielded full profiles with no anomalies. In order to effectively deal with this problem, we developed an authentication assay, which distinguishes between natural and artificial DNA based on methylation analysis of a set of genomic loci: in natural DNA, some loci are methylated and others are unmethylated, while in artificial DNA all loci are unmethylated. The assay was tested on natural and artificial samples of blood, saliva, and touched surfaces, with complete success. Adopting an authentication assay for casework samples as part of the forensic procedure is necessary for maintaining the high credibility of DNA evidence in the judiciary system.

A comprehensive screen for volatile organic compounds in biological fluids.

PubMed

Sharp, M E

2001-10-01

A headspace gas chromatographic (GC) screen for common volatile organic compounds in biological fluids is reported. Common GC phases, DB-1 and DB-WAX, with split injection provide separation and identification of more than 40 compounds in a single 20-min run. In addition, this method easily accommodates quantitation. The screen detects commonly encountered volatile compounds at levels below 4 mg%. A control mixture, providing qualitative and semiquantitative information, is described. For comparison, elution of the volatiles on a specialty phase, DB-624, is reported. This method is an expansion and modification of a screen that had been used for more than 20 years. During its first year of use, the expanded screen has proven to be advantageous in routine forensic casework.

Extended specificity studies of mRNA assays used to infer human organ tissues and body fluids.

PubMed

van den Berge, Margreet; Sijen, Titia

2017-12-01

Messenger RNA (mRNA) profiling is a technique increasingly applied for the forensic identification of body fluids and skin. More recently, an mRNA-based organ typing assay was developed which allows for the inference of brain, lung, liver, skeletal muscle, heart, kidney, and skin tissue. When applying this organ typing system in forensic casework for the presence of animal, rather than human, tissue is an alternative scenario to be proposed, for instance that bullets carry cell material from a hunting event. Even though mRNA profiling systems are commonly in silico designed to be primate specific, physical testing against other animal species is generally limited. In this study, human specificity of the organ tissue inferring system was assessed against organ tissue RNAs of various animals. Results confirm human specificity of the system, especially when utilizing interpretation rules considering multiple markers per cell type. Besides, we cross-tested our organ and body fluid mRNA assays against the target types covered by the other assay. Marker expression in the nontarget organ tissues and body fluids was observed to a limited extent, which emphasizes the importance of involving the case-specific context of the forensic samples in deciding which mRNA profiling assay to use and when for interpreting results. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Fifteen non-CODIS autosomal short tandem repeat loci multiplex data from nine population groups living in Taiwan.

PubMed

Hwa, Hsiao-Lin; Chang, Yih-Yuan; Lee, James Chun-I; Lin, Chun-Yen; Yin, Hsiang-Yi; Tseng, Li-Hui; Su, Yi-Ning; Ko, Tsang-Ming

2012-07-01

The analysis of autosomal short tandem repeat (STR) loci is a powerful tool in forensic genetics. We developed a multiplex system in which 15 non-Combined DNA Index System autosomal STRs (D3S1744, D4S2366, D8S1110, D10S2325, D12S1090, D13S765, D14S608, Penta E, D17S1294, D18S536, D18S1270, D20S470, D21S1437, Penta D, and D22S683) could be amplified in one single polymerase chain reaction. DNA samples from 1,098 unrelated subjects of nine population groups living in Taiwan, including Taiwanese Han, indigenous Taiwanese of Taiwan Island, Tao, mainland Chinese, Filipinos, Thais, Vietnamese, Indonesians, and Caucasians, were collected and analyzed using this system. The distributions of the allelic frequencies and the forensic parameters of each population group were presented. The combined discrimination power and the combined power of exclusion were high in all population groups tested in this study. A multidimensional scaling plot of these nine population groups based on the Reynolds' genetic distances calculated from 15 autosomal STRs was constructed, and the genetic substructure in this area was presented. In conclusion, this 15 autosomal STR multiplex system provides highly informative STR data and appears useful in forensic casework and parentage testing in different populations.

Forensic DNA typing from teeth using demineralized root tips.

PubMed

Corrêa, Heitor Simões Dutra; Pedro, Fabio Luis Miranda; Volpato, Luiz Evaristo Ricci; Pereira, Thiago Machado; Siebert Filho, Gilberto; Borges, Álvaro Henrique

2017-11-01

Teeth are widely used samples in forensic human genetic identification due to their persistence and practical sampling and processing. Their processing, however, has changed very little in the last 20 years, usually including powdering or pulverization of the tooth. The objective of this study was to present demineralized root tips as DNA sources while, at the same time, not involving powdering the samples or expensive equipment for teeth processing. One to five teeth from each of 20 unidentified human bodies recovered from midwest Brazil were analyzed. Whole teeth were demineralized in EDTA solution with daily solution change. After a maximum of approximately seven days, the final millimeters of the root tip was excised. This portion of the sample was used for DNA extraction through a conventional organic protocol. DNA quantification and STR amplification were performed using commercial kits followed by capillary electrophoresis on 3130 or 3500 genetic analyzers. For 60% of the unidentified bodies (12 of 20), a full genetic profile was obtained from the extraction of the first root tip. By the end of the analyses, full genetic profiles were obtained for 85% of the individuals studied, of which 80% were positively identified. This alternative low-tech approach for postmortem teeth processing is capable of extracting DNA in sufficient quantity and quality for forensic casework, showing that root tips are viable nuclear DNA sources even after demineralization. Copyright © 2017 Elsevier B.V. All rights reserved.

DNA degradation and genetic analysis of empty puparia: genetic identification limits in forensic entomology.

PubMed

Mazzanti, Morena; Alessandrini, Federica; Tagliabracci, Adriano; Wells, Jeffrey D; Campobasso, Carlo P

2010-02-25

Puparial cases are common remnants of necrophagous flies in crime investigations. They usually represent the longest developmental time and, therefore, they can be very useful for the estimation of the post-mortem interval (PMI). However, before any PMI estimate, it is crucial to identify the species of fly eclosed from each puparium associated with the corpse. Morphological characteristics of the puparium are often distinctive enough to permit a species identification. But, even an accurate morphological analysis of empty puparia cannot discriminate among different species of closely related flies. Furthermore, morphological identification may be impossible if the fly puparia are poorly preserved or in fragments. This study explores the applicability of biomolecular techniques on empty puparia and their fragments for identification purposes. A total of 63 empty puparia of necrophagous Diptera resulting from forensic casework were examined. Samples were divided into three groups according to size, type and time of eclosion in order to verify whether the physical characteristics and puparia weathering can influence the amount of DNA extraction. The results suggest that a reliable genetic identification of forensically important flies may also be performed from empty puparia and/or their fragments. However, DNA degradation can deeply compromise the genetic analysis since the older the fly puparia, the smaller are the amplified fragments. 2009 Elsevier Ireland Ltd. All rights reserved.

Evidence based practice: laboratory feedback informs forensic specimen collection in NSW.

PubMed

Nittis, Maria; Stark, Margaret

2014-07-01

The importance of having clear, evidence-based guidelines for the taking of forensic samples from suspects detained in police custody (persons of interest) and complainants of crime is essential for forensic practitioners. The need for such guidelines was seen as desirable in New South Wales (NSW) and a working group was set up comprising scientists, practitioners and police. Feedback from the laboratory regarding the results of the specimens taken by forensic practitioners throughout the State was received and analysed. This has resulted in changes to current practice and highlighted the need for further research in this area. It has also highlighted areas that have not changed in response to evidence A quality service demands transparency, process review, relevant research and feedback in order to progress. Examiners need to obtain the results for their cases in order to reinforce the value of the service they provide as well as to monitor and, where necessary, improve their forensic collection skills. Crown Copyright © 2014. Published by Elsevier Ltd. All rights reserved.

Comparative fly species composition on indoor and outdoor forensic cases in Malaysia.

PubMed

Syamsa, Rizal Abdullah; Omar, Baharudin; Ahmad, Firdaus Mohd Salleh; Hidayatulfathi, Othman; Shahrom, Abd Wahid

2017-01-01

Forensic entomology refers to the science of collection and analysis of insect evidence in order to determine the minimum time period since death. This study aimed to investigate the occurrence of forensically important flies on 34 human remains referred to Universiti Kebangsaan Malaysia Medical Centre over a period of three years. Entomological specimens were collected at the death scenes and/or during autopsies. Live specimens were reared into adults while preserved specimens were processed for species identification. Five families, seven genera and nine species of flies were identified from human remains. The results of the study showed Chrysomya megacephala (Calliphoridae) maggots occurred on corpses with the highest frequency (70.6%), followed by Ch. rufifacies (Calliphoridae) (44.1%), sarcophagid fly (Sarcophagidae) (38.2%), Synthesiomya nudiseta (Muscidae) (20.6%), Megaselia scalaris (Phoridae) (14.7%), Lucilia cuprina (Calliphoridae) (5.9%), Ch. nigripes (Calliphoridae) (5.9%), Eristalis spp. (Syrphidae) (5.9%) and Hydrotaea spinigera (Muscidae) (2.9%). The greatest fly diversity occurred on remains recovered indoors (eight species) compared to outdoors (three species). Whilst, single and double infestations were common for both indoor and outdoor cases, multiple infestation of up to six species was observed in one of the indoor cases. Although large numbers of fly species were found on human remains, the predominant species were still those of Chrysomya, while S. nudiseta was found only on human remains recovered from indoors. The present study provides additional knowledge in the context of Malaysian forensic entomology and the distribution of forensically important flies which is of relevance to forensic science. Copyright © 2016 Elsevier Ltd and Faculty of Forensic and Legal Medicine. All rights reserved.

[Practice value of whole genome amplification technology to be used in forensic science and analysis of its result].

PubMed

Deng, Jian-qiang; Hou, Yi-ping

2005-08-01

Genetic analysis from forensic microsamples is a urgent, difficult task in forensic science, because it is frequently limited by the amount of specimen available in forensic practice, much effort has been carried out to resolve this difficulty. Whole genome amplification (WGA) technology, which was developing quickly in these years, has been thought to be a powerful, reliable and efficient strategy in analysis of minute amount DNA on many fields. In this review, we discuss its application in forensic science.

Evaluation of the Universal Viral Transport system for long-term storage of virus specimens for microbial forensics.

PubMed

Hosokawa-Muto, Junji; Fujinami, Yoshihito; Mizuno, Natsuko

2015-08-01

Forensic microbial specimens, including bacteria and viruses, are collected at biocrime and bioterrorism scenes. Although it is preferable that the pathogens in these samples are alive and kept in a steady state, the samples may be stored for prolonged periods before analysis. Therefore, it is important to understand the effects of storage conditions on the pathogens contained within such samples. To evaluate the capacity to preserve viable virus and the viral genome, influenza virus was added to the transport medium of the Universal Viral Transport system and stored for over 3 months at various temperatures, after which virus titrations and quantitative analysis of the influenza hemagglutinin gene were performed. Although viable viruses became undetectable 29 days after the medium was stored at room temperature, viruses in the medium stored at 4°C were viable even after 99 days. A quantitative PCR analysis indicated that the hemagglutinin gene was maintained for 99 days at both 4°C and room temperature. Therefore, long-term storage at 4°C has little effect on viable virus and viral genes, so the Universal Viral Transport system can be useful for microbial forensics. This study provides important information for the handling of forensic virus specimens. Copyright © 2015 Elsevier Ltd and Faculty of Forensic and Legal Medicine. All rights reserved.

Animal Models in Forensic Science Research: Justified Use or Ethical Exploitation?

PubMed

Mole, Calvin Gerald; Heyns, Marise

2018-05-01

A moral dilemma exists in biomedical research relating to the use of animal or human tissue when conducting scientific research. In human ethics, researchers need to justify why the use of humans is necessary should suitable models exist. Conversely, in animal ethics, a researcher must justify why research cannot be carried out on suitable alternatives. In the case of medical procedures or therapeutics testing, the use of animal models is often justified. However, in forensic research, the justification may be less evident, particularly when research involves the infliction of trauma on living animals. To determine how the forensic science community is dealing with this dilemma, a review of literature within major forensic science journals was conducted. The frequency and trends of the use of animals in forensic science research was investigated for the period 1 January 2012-31 December 2016. The review revealed 204 original articles utilizing 5050 animals in various forms as analogues for human tissue. The most common specimens utilized were various species of rats (35.3%), pigs (29.3%), mice (17.7%), and rabbits (8.2%) although different specimens were favored in different study themes. The majority of studies (58%) were conducted on post-mortem specimens. It is, however, evident that more needs to be done to uphold the basic ethical principles of reduction, refinement and replacement in the use of animals for research purposes.

Extraction of DNA from forensic-type sexual assault specimens using simple, rapid sonication procedures.

PubMed

Crouse, C A; Ban, J D; D'Alessio, J K

1993-10-01

Sonication procedures for the extraction of DNA from forensic-type semen specimens have been developed, which, when compared to currently utilized sperm DNA extraction techniques, are simple, rapid and result in comparable DNA yields. Sperm DNA extraction by sonication was performed on whole semen, seminal stains, buccal swabs and post-coital specimens. Ultrasound disruption of sperm cells and their ultimate release of cellular DNA has been conducted in the presence of sperm wash buffers followed by organic extraction or Chelex 100 with little or no compromise to DNA quality, quantity or amplifiability. Two advantages of sonication over currently used forensic techniques to extract sperm DNA include 1) sperm DNA extraction that occurs within five minutes of sonication compared with an hour or greater for water bath incubations in classic enzyme digestion DNA extractions and 2) one less preparatory step with the Chelex/sonication protocol and three less steps with the sonication/organic protocol compared with other procedures thus eliminating potential sample-to-sample cross-contamination. Sperm DNA extracted by optimum sonication procedures was used for forensic HLA DQ alpha typing and restriction fragment length polymorphisms analysis without any adverse effects on typing results.

Analysis of Sertraline in Postmortem Fluids and Tissues in 11 Aviation Accident Victims

DTIC Science & Technology

2012-11-01

likely undergoes significant postmortem redistribution. 17. Key Words 18. Distribution Statement Forensic Toxicology , Sertraline, Norsertraline... Toxicology .. Forensic Sci Int,.142:.75-100.(2004) . 29 .. Skopp,.G ..Postmortem.Toxicology .. Forensic Sci Med Pathol,.6:.314-25.(2010) . ... toxicological . analysis. on. specimens.from.….aircraft.accident.fatalities”.and.“in- vestigate.….general.aviation.and.air.carrier.accidents. and. search

Is 'virtual histology' the next step after the 'virtual autopsy'? Magnetic resonance microscopy in forensic medicine.

PubMed

Thali, M J; Dirnhofer, R; Becker, R; Oliver, W; Potter, K

2004-10-01

The study aimed to validate magnetic resonance microscopy (MRM) studies of forensic tissue specimens (skin samples with electric injury patterns) against the results from routine histology. Computed tomography and magnetic resonance imaging are fast becoming important tools in clinical and forensic pathology. This study is the first forensic application of MRM to the analysis of electric injury patterns in human skin. Three-dimensional high-resolution MRM images of fixed skin specimens provided a complete 3D view of the damaged tissues at the site of an electric injury as well as in neighboring tissues, consistent with histologic findings. The image intensity of the dermal layer in T2-weighted MRM images was reduced in the central zone due to carbonization or coagulation necrosis and increased in the intermediate zone because of dermal edema. A subjacent blood vessel with an intravascular occlusion supports the hypothesis that current traveled through the vascular system before arcing to ground. High-resolution imaging offers a noninvasive alternative to conventional histology in forensic wound analysis and can be used to perform 3D virtual histology.

Pharmaceutical identifier confirmation via DART-TOF.

PubMed

Easter, Jacob L; Steiner, Robert R

2014-07-01

Pharmaceutical analysis comprises a large amount of the casework in forensic controlled substances laboratories. In order to reduce the time of analysis for pharmaceuticals, a Direct Analysis in Real Time ion source coupled with an accurate mass time-of-flight (DART-TOF) mass spectrometer was used to confirm identity. DART-TOF spectral data for pharmaceutical samples were analyzed and evaluated by comparison to standard spectra. Identical mass pharmaceuticals were differentiated using collision induced dissociation fragmentation, present/absent ions, and abundance comparison box plots; principal component analysis (PCA) and linear discriminant analysis (LDA) were used for differentiation of identical mass mixed drug spectra. Mass assignment reproducibility and robustness tests were performed on the DART-TOF spectra. Impacts on the forensic science community include a decrease in analysis time over the traditional gas chromatograph/mass spectrometry (GC/MS) confirmations, better laboratory efficiency, and simpler sample preparation. Using physical identifiers and the DART-TOF to confirm pharmaceutical identity will eliminate the use of GC/MS and effectively reduce analysis time while still complying with accepted analysis protocols. This will prove helpful in laboratories with large backlogs and will simplify the confirmation process. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

Simultaneous detection of human mitochondrial DNA and nuclear-inserted mitochondrial-origin sequences (NumtS) using forensic mtDNA amplification strategies and pyrosequencing technology.

PubMed

Bintz, Brittania J; Dixon, Groves B; Wilson, Mark R

2014-07-01

Next-generation sequencing technologies enable the identification of minor mitochondrial DNA variants with higher sensitivity than Sanger methods, allowing for enhanced identification of minor variants. In this study, mixtures of human mtDNA control region amplicons were subjected to pyrosequencing to determine the detection threshold of the Roche GS Junior(®) instrument (Roche Applied Science, Indianapolis, IN). In addition to expected variants, a set of reproducible variants was consistently found in reads from one particular amplicon. A BLASTn search of the variant sequence revealed identity to a segment of a 611-bp nuclear insertion of the mitochondrial control region (NumtS) spanning the primer-binding sites of this amplicon (Nature 1995;378:489). Primers (Hum Genet 2012;131:757; Hum Biol 1996;68:847) flanking the insertion were used to confirm the presence or absence of the NumtS in buccal DNA extracts from twenty donors. These results further our understanding of human mtDNA variation and are expected to have a positive impact on the interpretation of mtDNA profiles using deep-sequencing methods in casework. © 2014 American Academy of Forensic Sciences.

Rapid microfluidic analysis of a Y-STR multiplex for screening of forensic samples.

PubMed

Gibson-Daw, Georgiana; Albani, Patricia; Gassmann, Marcus; McCord, Bruce

2017-02-01

In this paper, we demonstrate a rapid analysis procedure for use with a small set of rapidly mutating Y chromosomal short tandem repeat (Y-STR) loci that combines both rapid polymerase chain reaction (PCR) and microfluidic separation elements. The procedure involves a high-speed polymerase and a rapid cycling protocol to permit PCR amplification in 16 min. The resultant amplified sample is next analysed using a short 1.8-cm microfluidic electrophoresis system that permits a four-locus Y-STR genotype to be produced in 80 s. The entire procedure takes less than 25 min from sample collection to result. This paper describes the rapid amplification protocol as well as studies of the reproducibility and sensitivity of the procedure and its optimisation. The amplification process utilises a small high-speed thermocycler, microfluidic device and compact laptop, making it portable and potentially useful for rapid, inexpensive on-site genotyping. The four loci used for the multiplex were selected due to their rapid mutation rates and should proved useful in preliminary screening of samples and suspects. Overall, this technique provides a method for rapid sample screening of suspect and crime scene samples in forensic casework. Graphical abstract ᅟ.

Massively parallel sequencing of 17 commonly used forensic autosomal STRs and amelogenin with small amplicons.

PubMed

Kim, Eun Hye; Lee, Hwan Young; Yang, In Seok; Jung, Sang-Eun; Yang, Woo Ick; Shin, Kyoung-Jin

2016-05-01

The next-generation sequencing (NGS) method has been utilized to analyze short tandem repeat (STR) markers, which are routinely used for human identification purposes in the forensic field. Some researchers have demonstrated the successful application of the NGS system to STR typing, suggesting that NGS technology may be an alternative or additional method to overcome limitations of capillary electrophoresis (CE)-based STR profiling. However, there has been no available multiplex PCR system that is optimized for NGS analysis of forensic STR markers. Thus, we constructed a multiplex PCR system for the NGS analysis of 18 markers (13CODIS STRs, D2S1338, D19S433, Penta D, Penta E and amelogenin) by designing amplicons in the size range of 77-210 base pairs. Then, PCR products were generated from two single-sources, mixed samples and artificially degraded DNA samples using a multiplex PCR system, and were prepared for sequencing on the MiSeq system through construction of a subsequent barcoded library. By performing NGS and analyzing the data, we confirmed that the resultant STR genotypes were consistent with those of CE-based typing. Moreover, sequence variations were detected in targeted STR regions. Through the use of small-sized amplicons, the developed multiplex PCR system enables researchers to obtain successful STR profiles even from artificially degraded DNA as well as STR loci which are analyzed with large-sized amplicons in the CE-based commercial kits. In addition, successful profiles can be obtained from mixtures up to a 1:19 ratio. Consequently, the developed multiplex PCR system, which produces small size amplicons, can be successfully applied to STR NGS analysis of forensic casework samples such as mixtures and degraded DNA samples. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Comparative evaluation of different extraction and quantification methods for forensic RNA analysis.

PubMed

Grabmüller, Melanie; Madea, Burkhard; Courts, Cornelius

2015-05-01

Since about 2005, there is increasing interest in forensic RNA analysis whose versatility may very favorably complement traditional DNA profiling in forensic casework. There is, however, no method available specifically dedicated for extraction of RNA from forensically relevant sample material. In this study we compared five commercially available and commonly used RNA extraction kits and methods (mirVana™ miRNA Isolation Kit Ambion; Trizol® Reagent, Invitrogen; NucleoSpin® miRNA Kit Macherey-Nagel; AllPrep DNA/RNA Mini Kit and RNeasy® Mini Kit both Qiagen) to assess their relative effectiveness of yielding RNA of good quality and their compatibility with co-extraction of DNA amenable to STR profiling. We set up samples of small amounts of dried blood, liquid saliva, semen and buccal mucosa that were aged for different time intervals for co-extraction of RNA and DNA. RNA quality was assessed by determination of 'RNA integrity number' (RIN) and quantitative PCR based expression analysis. DNA quality was assessed via monitoring STR typing success rates. By comparison, the different methods exhibited considerable differences between RNA and DNA yields, RNA quality values and expression levels, and STR profiling success, with the AllPrep DNA/RNA Mini Kit and the NucleoSpin® miRNA Kit excelling at DNA co-extraction and RNA results, respectively. Overall, there was no 'best' method to satisfy all demands of comprehensible co-analysis of RNA and DNA and it appears that each method has specific merits and flaws. We recommend to cautiously choose from available methods and align its characteristics with the needs of the experimental setting at hand. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Forensic validation of the PowerPlex® ESI 16 STR Multiplex and comparison of performance with AmpFlSTR® SGM Plus®.

PubMed

Tucker, Valerie C; Kirkham, Amanda J; Hopwood, Andrew J

2012-05-01

We describe the forensic validation of Promega's PowerPlex® European Standard Investigator 16 (ESI 16) multiplex kit and compare results generated with the AmpFlSTR® SGM Plus® (SGM+) multiplex. ESI 16 combines the loci contained within the SGM+ multiplex with five additional loci: D2S441, D10S1248, D22S1045, D1S1656, and D12S391. A relative reduction in amplicon size of the SGM+ loci facilitates an increased robustness and amplification success of these amplicons with degraded DNA samples. Tests performed herein supplement ESI 16 data published previously with sensitivity, profile quality, mock casework, inhibitor and mixture study data collected in our laboratories in alignment with our internal technical and quality guidelines and those issued by the Scientific Working Group on DNA Analysis Methods (SWGDAM), the DNA Advisory Board (DAB) and the DNA working group (DNAWG) of the European Network of Forensic Science Institutes (ENFSI). Full profiles were routinely generated from a fully heterozygous single source DNA template using 62.5 pg for ESI 16 and 500 pg for SGM+. This increase in sensitivity has a consequent effect on mixture analyses and the detection of minor mixture components. The improved PCR chemistry confers enhanced tolerance to high levels of laboratory prepared inhibitors compared with SGM+ results. In summary, our results demonstrate that the ESI 16 multiplex kit is more robust and sensitive compared with SGM+ and will be a suitable replacement system for the analysis of forensic DNA samples providing compliance with the European standard set of STR loci.

Investigator® HDplex (Qiagen) reference population database for forensic use in Argentina.

PubMed

Martínez, Gustavo; Borosky, Alicia; Corach, Daniel; Llull, Cintia; Locarno, Laura; Lojo, Mercedes; Marino, Miguel; Miozzo, María Cecilia; Modesti, Nidia; Pacharoni, Carla; Pilili, Juan Pablo; Ramella, María Isabel; Sala, Andrea; Schaller, Cecilia; Vullo, Carlos; Toscanini, Ulises

2017-01-01

Currently, autosomal Short Tandem Repeat (STR) markers represent the method of election in forensic human identification. Commercial kits of most common use nowadays -e.g. PowerPlex ® Fusion, Promega Corp.; AmpFlSTR GlobalFiler, Thermofisher scientific; Investigator 24Plex QS,Qiagen-, allow the co-amplification of 23 highly polymorphic STR loci providing a high discrimination power in human identity testing. However, in complex kinship analysis and familial database searches involving distant relationships, additional DNA typing is often required in order to achieve well-founded conclusions. The recently developed kit Investigator ® HDplex (Qiagen) co-amplify twelve autosomal STRs markers (D7S1517, D3S1744, D12S391, D2S1360, D6S474, D4S2366, D8S1132, D5S2500, D18S51, D21S2055, D10S2325, SE33), nine of which are not present in the above mentioned kits, providing a set of efficient supplementary markers for human identification purposes. In this study we genotyped a sample of 980 individuals from urban areas of ten Argentinean provinces using the Investigator ® HDplex kit, aiming to provide forensic estimates for use in forensic casework and parentage testing in Argentina. We report reference allelic frequency databases for each of the provinces studied as well as for the combined samples. No deviation of Hardy-Weinberg equilibrium was observed. A reasonable discrimination capacity and power of exclusion was estimated which allowed predicting an acceptable forensic behavior of this kit, either to be used as the main STR panel for simple cases or as an auxiliary tool in complex cases. Additionally, population comparison tests showed that the studied samples are relatively homogeneous across the country for these STR set. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Epigenetic discrimination of identical twins from blood under the forensic scenario.

PubMed

Vidaki, Athina; Díez López, Celia; Carnero-Montoro, Elena; Ralf, Arwin; Ward, Kirsten; Spector, Timothy; Bell, Jordana T; Kayser, Manfred

2017-11-01

Monozygotic (MZ) twins share the same STR profile, demonstrating a practical problem in forensic casework. DNA methylation has provided a suitable resource for MZ twin differentiation; however, studies addressing the forensic feasibility are lacking. Here, we investigated epigenetic MZ twin differentiation from blood under the forensic scenario comprising i) the discovery of candidate markers in reference-type blood DNA via genome-wide analysis, ii) the technical validation of candidate markers in reference-type blood DNA using a suitable targeted method, and iii) the analysis of the validated markers in trace-type DNA. Genome-wide methylation analysis in blood DNA from 10 MZ twin pairs resulted in 19-111 twin-differentially methylated sites (tDMSs) per pair with >0.3 twin-to-twin differences. Considering all top three candidate tDMSs across all pairs in the technical validation based on methylation-specific qPCR, 67.85% generated >0.1 twin-to-twin differences. Of the validated tDMSs, 68.4% showed >0.1 twin-to-twin differences with qPCR in trace-type DNA across 8 pairs. Using an updated marker selection strategy, 8 additional candidate tDMSs were obtained for an example MZ pair, of which 7 showed >0.1 twin-to-twin differences in both reference- and trace-type DNA. Lastly, we introduce a high-resolution melting curve analysis of the entire fragment that can complement the proposed approach. Overall, our study demonstrates the general feasibility of epigenetic twin differentiation in the forensic context and highlights that the number of informative tDMSs in the final trace DNA analysis is crucial, as some candidate markers identified in reference DNA were shown not informative in the trace DNA due to various, including technical, reasons. Future studies will need to address the optimal number of epigenetic markers required for reliable identification of MZ twin individuals including statistical considerations. Copyright © 2017 Elsevier B.V. All rights reserved.

More comprehensive forensic genetic marker analyses for accurate human remains identification using massively parallel DNA sequencing.

PubMed

Ambers, Angie D; Churchill, Jennifer D; King, Jonathan L; Stoljarova, Monika; Gill-King, Harrell; Assidi, Mourad; Abu-Elmagd, Muhammad; Buhmeida, Abdelbaset; Al-Qahtani, Mohammed; Budowle, Bruce

2016-10-17

Although the primary objective of forensic DNA analyses of unidentified human remains is positive identification, cases involving historical or archaeological skeletal remains often lack reference samples for comparison. Massively parallel sequencing (MPS) offers an opportunity to provide biometric data in such cases, and these cases provide valuable data on the feasibility of applying MPS for characterization of modern forensic casework samples. In this study, MPS was used to characterize 140-year-old human skeletal remains discovered at a historical site in Deadwood, South Dakota, United States. The remains were in an unmarked grave and there were no records or other metadata available regarding the identity of the individual. Due to the high throughput of MPS, a variety of biometric markers could be typed using a single sample. Using MPS and suitable forensic genetic markers, more relevant information could be obtained from a limited quantity and quality sample. Results were obtained for 25/26 Y-STRs, 34/34 Y SNPs, 166/166 ancestry-informative SNPs, 24/24 phenotype-informative SNPs, 102/102 human identity SNPs, 27/29 autosomal STRs (plus amelogenin), and 4/8 X-STRs (as well as ten regions of mtDNA). The Y-chromosome (Y-STR, Y-SNP) and mtDNA profiles of the unidentified skeletal remains are consistent with the R1b and H1 haplogroups, respectively. Both of these haplogroups are the most common haplogroups in Western Europe. Ancestry-informative SNP analysis also supported European ancestry. The genetic results are consistent with anthropological findings that the remains belong to a male of European ancestry (Caucasian). Phenotype-informative SNP data provided strong support that the individual had light red hair and brown eyes. This study is among the first to genetically characterize historical human remains with forensic genetic marker kits specifically designed for MPS. The outcome demonstrates that substantially more genetic information can be obtained from the same initial quantities of DNA as that of current CE-based analyses.

Analysis of cis and trans 3-Methylfentanyl by Liquid Chromatography High Resolution Mass Spectrometry and Findings in Forensic Toxicology Casework.

PubMed

Fogarty, Melissa F; Papsun, Donna M; Logan, Barry K

2018-05-25

3-Methylfentanyl (3-MF), N-(3-methyl-1-phenethyl-4-piperidyl)-N-phenyl-propanamide, has reappeared in the United States illicit drug market since its disappearance after a series of overdose deaths in 1988.3-MF presents an analytical challenge, due to presence of cis and trans stereoisomers, each with different potencies, and ultimately very low concentrations in the blood after use. A method was developed using liquid chromatography time-of-flight mass spectrometry for the analysis of (±)-cis-3-MF and (±)-trans-3-MF in blood specimens after solid phase extraction. The linear dynamic range of this method was 0.1-10 ng/mL. Blood samples from 25 postmortem cases and 2 human performance case involving 3-MF were submitted for quantitative analysis. The mean and median concentration for the (±)-cis-3-MF were 0.84 ng/mL (±0.81) and 0.66 ng/mL, respectively, range 0.14-3.43 ng/mL. The resulting (±)-trans-3-MF mean concentration was 0.46 ng/mL (±0.38) and the median concentration was 0.37 ng/mL with a range of 0.11-1.90 ng/mL. The resulting (±)-cis-3-MF and (±)-trans-3-MF concentrations were summed to give the total amount of 3-MF present in the case with the resulting average concentration at 1.28 ng/mL (±1.16), median at 1 ng/mL and range 0.18-5.18. As the estimated dose of this compound is approximately 0.1-0.5 mg with the resulting concentrations in the sub-nanogram range, it is necessary for forensic toxicology laboratories to obtain instruments sensitive enough to detect these substances in driving under the influence of drugs and postmortem cases. Quantitation of 3-MF with separation of (±)-cis and (±)-trans-3-MF provides additional detail for more specific toxicological interpretation. This article is protected by copyright. All rights reserved.

Postcraniometric sex and ancestry estimation in South Africa: a validation study.

PubMed

Liebenberg, Leandi; Krüger, Gabriele C; L'Abbé, Ericka N; Stull, Kyra E

2018-05-24

With the acceptance of the Daubert criteria as the standards for best practice in forensic anthropological research, more emphasis is being placed on the validation of published methods. Methods, both traditional and novel, need to be validated, adjusted, and refined for optimal performance within forensic anthropological analyses. Recently, a custom postcranial database of modern South Africans was created for use in Fordisc 3.1. Classification accuracies of up to 85% for ancestry estimation and 98% for sex estimation were achieved using a multivariate approach. To measure the external validity and report more realistic performance statistics, an independent sample was tested. The postcrania from 180 black, white, and colored South Africans were measured and classified using the custom postcranial database. A decrease in accuracy was observed for both ancestry estimation (79%) and sex estimation (95%) of the validation sample. When incorporating both sex and ancestry simultaneously, the method achieved 70% accuracy, and 79% accuracy when sex-specific ancestry analyses were run. Classification matrices revealed that postcrania were more likely to misclassify as a result of ancestry rather than sex. While both sex and ancestry influence the size of an individual, sex differences are more marked in the postcranial skeleton and are therefore easier to identify. The external validity of the postcranial database was verified and therefore shown to be a useful tool for forensic casework in South Africa. While the classification rates were slightly lower than the original method, this is expected when a method is generalized.

High-quality mtDNA control region sequences from 680 individuals sampled across the Netherlands to establish a national forensic mtDNA reference database.

PubMed

Chaitanya, Lakshmi; van Oven, Mannis; Brauer, Silke; Zimmermann, Bettina; Huber, Gabriela; Xavier, Catarina; Parson, Walther; de Knijff, Peter; Kayser, Manfred

2016-03-01

The use of mitochondrial DNA (mtDNA) for maternal lineage identification often marks the last resort when investigating forensic and missing-person cases involving highly degraded biological materials. As with all comparative DNA testing, a match between evidence and reference sample requires a statistical interpretation, for which high-quality mtDNA population frequency data are crucial. Here, we determined, under high quality standards, the complete mtDNA control-region sequences of 680 individuals from across the Netherlands sampled at 54 sites, covering the entire country with 10 geographic sub-regions. The complete mtDNA control region (nucleotide positions 16,024-16,569 and 1-576) was amplified with two PCR primers and sequenced with ten different sequencing primers using the EMPOP protocol. Haplotype diversity of the entire sample set was very high at 99.63% and, accordingly, the random-match probability was 0.37%. No population substructure within the Netherlands was detected with our dataset. Phylogenetic analyses were performed to determine mtDNA haplogroups. Inclusion of these high-quality data in the EMPOP database (accession number: EMP00666) will improve its overall data content and geographic coverage in the interest of all EMPOP users worldwide. Moreover, this dataset will serve as (the start of) a national reference database for mtDNA applications in forensic and missing person casework in the Netherlands. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

A novel histological technique for distinguishing between epithelial cells in forensic casework.

PubMed

French, Claire E V; Jensen, Cynthia G; Vintiner, Susan K; Elliot, Douglas A; McGlashan, Susan R

2008-06-10

There are a number of forensic cases in which the identification of the epithelial cell type from which DNA originated would provide important probative evidence. This study aimed to develop a technique using histological staining of fixed cells to distinguish between skin, buccal and vaginal epithelium. First, 11 different stains were screened on formalin-fixed, wax-embedded cells from five women. Samples were analysed qualitatively by examining staining patterns (colour) and morphology (absence or presence of nuclei). Three of the staining methods--Dane's, Csaba's and Ayoub-Shklar--were successful in distinguishing skin epithelial cells from buccal and vaginal. Second, cells were smeared directly onto slides, fixed with one of five fixatives and stained with one of the three stains mentioned above. Methanol fixation, coupled with the Dane's staining method, specific to keratin, was the only technique that distinguished between all three cell types. Skin cells stained magenta, red and orange and lacked nuclei; buccal cells stained predominantly orange-pink with red nuclei; while vaginal cells stained bright orange with orange nuclei and a blue extracellular hue. This staining pattern in vaginal cells was consistent in samples collected from 50 women aged between 18 and 67. Identification of cell type from unlabelled micrographs by 10 trained observers showed a mean success rate of 95%. The results of this study demonstrate that histological staining may provide forensic scientists with a technique for distinguishing between skin, buccal and vaginal epithelial cells and thus would enable more conclusive analyses when investigating sexual assault cases.

Adult femicide victims in forensic autopsy in Taiwan: A 10-year retrospective study.

PubMed

Fong, Wen-Li; Pan, Chih-Hsin; Lee, James Chun-I; Lee, Tsui-Ting; Hwa, Hsiao-Lin

2016-09-01

Violence against women and adult femicides are critical medico-legal issues worldwide. Intimate partner violence is one of the leading contributory risk factors. This study aimed to describe the characteristics of femicides in Taiwan. A retrospective analysis of forensic autopsy records of adult femicide victims in Taiwan during a 10-year period was carried out. The age, victim-offender relationship, injury patterns and causes of death were analyzed. Among the 220 adult femicide victims recruited, 114 were killed by intimate partners and 106 were killed by non-intimate partner offenders. The average age of victims killed by intimate partners (40.0 y/o) were younger than those killed by non-intimate partner perpetrators (48.6 y/o). The most common site of injuries in the intimate partner group and the non-intimate partner group was the neck and the upper limbs, respectively. The rates of bruise and intracranial injury of non-intimate partner group were significantly higher than that of the intimate partner group. The most common causes of death in both groups were strangulation and sharp force injury. The heart injury was significantly more frequent in victims offended by intimate partners than by other assailants. The characteristics of adult femicides, and the patterns of injury in victims killed by intimate partners and non-intimate partner offenders were different. This data is helpful for corpus inspection in forensic casework and for strategic planning of femicides prevention. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Optimising crime scene temperature collection for forensic entomology casework.

PubMed

Hofer, Ines M J; Hart, Andrew J; Martín-Vega, Daniel; Hall, Martin J R

2017-01-01

The value of minimum post-mortem interval (minPMI) estimations in suspicious death investigations from insect evidence using temperature modelling is indisputable. In order to investigate the reliability of the collected temperature data used for modelling minPMI, it is necessary to study the effects of data logger location on the accuracy and precision of measurements. Digital data logging devices are the most commonly used temperature measuring devices in forensic entomology, however, the relationship between ambient temperatures (measured by loggers) and body temperatures has been little studied. The placement of loggers in this study in three locations (two outdoors, one indoors) had measurable effects when compared with actual body temperature measurements (simulated with pig heads), some more significant than others depending on season, exposure to the environment and logger location. Overall, the study demonstrated the complexity of the question of optimal logger placement at a crime scene and the potential impact of inaccurate temperature data on minPMI estimations, showing the importance of further research in this area and development of a standard protocol. Initial recommendations are provided for data logger placement (within a Stevenson Screen where practical), situations to avoid (e.g. placement of logger in front of windows when measuring indoor temperatures), and a baseline for further research into producing standard guidelines for logger placement, to increase the accuracy of minPMI estimations and, thereby, the reliability of forensic entomology evidence in court. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Population Genetics of Identifiler System in Malaysia.

PubMed

Nakamura, Yasutaka; Samejima, Michinaga; Minaguchi, Kiyoshi; Nambiar, Phrabhakaran

2016-01-01

Short tandem repeat (STR) polymorphisms were investigated in 341 unrelated Malay individuals (218 males and 123 females) living in or around Kuala Lumpur by using a forensic analysts kit. The following STRs were targeted: D8S1179, D21S11, D7S820, CSF1PO, D3S1358, TH01, D13S317, D16S539, D2S1338, D19S433, vWA, TPOX, D18S51, D5S818, and FGA. The purpose of this study was to elucidate population genetics in Malaysia and calculate statistical parameters for forensic and anthropological research. Data on these STRs in the target population were obtained and subjected to statistical analysis. Accordance with the Hardy-Weinberg equilibrium was proven for all the loci targeted. The combined power of discrimination was greater than 0.9999999999, indicating that this multiplex system is an excellent tool for forensic casework. The allele frequency in the data were weighed against that in four other local populations (Chinese, Iranian, Belgian, and African). The average coefficient of correlation was strongest in the order of Africa (0.092522), Belgium (0.264822), Iran (0.404363), and China (0.706661). These results are consistent with what is known about the anthropological history of and prehistoric human migration in the Malay region. We believe that these data offer a valuable anthropological resource, being applicable to the statistical evaluation of DNA evidence in human identification, as well as the determination of ethnicity in healthy populations.

Case studies in forensic soil examinations.

PubMed

Petraco, Nicholas; Kubic, Thomas A; Petraco, Nicholas D K

2008-07-04

The examination and comparison of forensic soil samples is discussed. The origin of a simple and easy to learn procedure used and modified by the authors is reviewed. The process begins with a preliminary observation, removal of artifacts, and sieving of each specimen. A specific size fraction is split into three fractions for color matching, polarized light microscopy (PLM) examination (particle counting) and optional gradient comparison. Next, several cases are reviewed in which the modified method was used to evaluate the likelihood of common origin for questioned and known specimens.

Factors associated with mental health services referrals for children investigated by child welfare.

PubMed

Fong, Hiu-Fai; Alegria, Margarita; Bair-Merritt, Megan H; Beardslee, William

2018-05-01

Although child welfare caseworkers are responsible for facilitating mental health services access for maltreated children, little is known about caseworkers' decisions to refer children to services. We aimed to identify factors associated with caseworker referral of children to mental health services after a maltreatment investigation. We analyzed data from 1956 children 2-17 years old from the Second National Survey of Child and Adolescent Well-being. We examined associations of children's predisposing, enabling, and need-related factors and caseworkers' work environment characteristics with referral to mental health services. Caseworkers referred 21.0% of children to mental health services. In multivariable analyses controlling for potential covariates, factors associated with increased odds of caseworker referral included: older child age; child sexual abuse (versus neglect); child out-of-home placement; caregiver mental health problems; prior maltreatment reports; clinically significant child behavioral problems; and child welfare agency collaborative ties with mental health providers (all p < .05). Factors associated with decreased odds of caseworker referral included child Black race (versus White race) and lack of insurance (versus Private insurance) (all p < .05). In summary, children's need for mental health services was positively associated with caseworker referral to services but certain predisposing and enabling factors and caseworker work environment characteristics also correlated with services referral. Interventions to reduce disparities in services referral by race and insurance type are critically needed. These may include child welfare agency implementation of policies for mental health screening, assessment, and services referral based on clinical need and establishment of child welfare-mental health agency collaborative ties. Copyright © 2018 Elsevier Ltd. All rights reserved.

Reducing turnover is not enough: The need for proficient organizational cultures to support positive youth outcomes in child welfare.

PubMed

Williams, Nathaniel J; Glisson, Charles

2013-11-01

High caseworker turnover has been identified as a factor in the poor outcomes of child welfare services. However, almost no empirical research has examined the relationship between caseworker turnover and youth outcomes in child welfare systems and there is an important knowledge gap regarding whether, and how, caseworker turnover relates to outcomes for youth. We hypothesized that the effects of caseworker turnover are moderated by organizational culture such that reduced caseworker turnover is only associated with improved youth outcomes in organizations with proficient cultures. The study applied hierarchical linear models (HLM) analysis to the second National Survey of Child and Adolescent Well-being (NSCAW II) with a U.S. nationwide sample of 2,346 youth aged 1.5- to 18-years-old and 1,544 caseworkers in 73 child welfare agencies. Proficient organizational culture was measured by caseworkers' responses to the Organizational Social Context (OSC) measure; staff turnover was reported by the agencies' directors; and youth outcomes were measured as total problems in psychosocial functioning with the Child Behavior Checklist (CBCL) completed by the youths' caregivers at intake and at 18 month follow-up. The association between caseworker turnover and youth outcomes was moderated by organizational culture. Youth outcomes were improved with lower staff turnover in proficient organizational cultures and the best outcomes occurred in organizations with low turnover and high proficiency. To be successful, efforts to improve child welfare services by lowering staff turnover must also create proficient cultures that expect caseworkers to be competent and responsive to the needs of the youth and families they serve.

The Importance of International Technical Nuclear Forensics to Deter Illicit Trafficking

DOE Office of Scientific and Technical Information (OSTI.GOV)

Smith, D K

2007-01-30

Illicit trafficking of nuclear materials is a transboundary problem that requires a cooperative approach involving international nuclear forensics to ensure all states understand the threat posed by nuclear smuggling as well as a means to best deter the movement of nuclear contraband. To achieve the objectives, all cases involving illicit trafficking of nuclear and radiological materials must be vigorously pursued and prosecuted when appropriate. The importance of outreach and formal government-to-government relationships with partner nations affected by nuclear trafficking cannot be under-estimated. States that are situated on smuggling routes may be well motivated to counter nuclear crimes to bolster theirmore » own border and transportation security as well as strengthen their economic and political viability. National law enforcement and atomic energy agencies in these states are aggressively pursuing a comprehensive strategy to counter nuclear smuggling through increasing reliance on technical nuclear forensics. As part of these activities, it is essential that these organizations be given adequate orientation to the best practices in this emerging discipline including the categorization of interdicted nuclear material, collection of traditional and nuclear forensic evidence, data analysis using optimized analytical protocols, and how to best fuse forensics information with reliable case input to best develop a law enforcement or national security response. The purpose of formalized USG relationship is to establish an institutional framework for collaboration in international forensics, improve standards of forensics practice, conduct joint exercises, and pursue case-work that benefits international security objectives. Just as outreach and formalized relationships are important to cultivate international nuclear forensics, linking nuclear forensics to ongoing national assistance in border and transpiration security, including port of entry of entry monitoring, nuclear safeguards, and emerging civilian nuclear power initiatives including the Global Nuclear Energy Partnership are crucial components of a successful nuclear detection and security architecture. Once illicit shipments of nuclear material are discovered at a border, the immediate next question will be the nature and the source of the material, as well as the identity of the individual(s) involved in the transfer as well as their motivations. The Nuclear Smuggling International Technical Working Group (ITWG) is a forum for the first responder, law enforcement, policy, and diplomatic community to partner with nuclear forensics experts worldwide to identify requirements and develop technical solutions in common. The ITWG was charted in 1996 and since that time approximately 30 member states and organizations have participated in 11 annual international meetings. The ITWG also works closely with the IAEA to provide countries with support for forensic analyses. Priorities include the development of common protocols for the collection of nuclear forensic evidence and laboratory investigations, organization of forensic round-robin analytical exercises and technical forensic assistance to requesting nations. To promote the science of nuclear forensics within the ITWG the Nuclear Forensics Laboratory Group was organized in 2004. A Model Action Plan for nuclear forensics was developed by the ITWG and published as an IAEA Nuclear security Series document to guide member states in their own forensics investigations. Through outreach, formalized partnerships, common approaches and security architectures, and international working groups, nuclear forensics provides an important contribution to promoting nuclear security and accountability.« less

Application of DNA-based methods in forensic entomology.

PubMed

Wells, Jeffrey D; Stevens, Jamie R

2008-01-01

A forensic entomological investigation can benefit from a variety of widely practiced molecular genotyping methods. The most commonly used is DNA-based specimen identification. Other applications include the identification of insect gut contents and the characterization of the population genetic structure of a forensically important insect species. The proper application of these procedures demands that the analyst be technically expert. However, one must also be aware of the extensive list of standards and expectations that many legal systems have developed for forensic DNA analysis. We summarize the DNA techniques that are currently used in, or have been proposed for, forensic entomology and review established genetic analyses from other scientific fields that address questions similar to those in forensic entomology. We describe how accepted standards for forensic DNA practice and method validation are likely to apply to insect evidence used in a death or other forensic entomological investigation.

Error rates in forensic DNA analysis: definition, numbers, impact and communication.

PubMed

Kloosterman, Ate; Sjerps, Marjan; Quak, Astrid

2014-09-01

Forensic DNA casework is currently regarded as one of the most important types of forensic evidence, and important decisions in intelligence and justice are based on it. However, errors occasionally occur and may have very serious consequences. In other domains, error rates have been defined and published. The forensic domain is lagging behind concerning this transparency for various reasons. In this paper we provide definitions and observed frequencies for different types of errors at the Human Biological Traces Department of the Netherlands Forensic Institute (NFI) over the years 2008-2012. Furthermore, we assess their actual and potential impact and describe how the NFI deals with the communication of these numbers to the legal justice system. We conclude that the observed relative frequency of quality failures is comparable to studies from clinical laboratories and genetic testing centres. Furthermore, this frequency is constant over the five-year study period. The most common causes of failures related to the laboratory process were contamination and human error. Most human errors could be corrected, whereas gross contamination in crime samples often resulted in irreversible consequences. Hence this type of contamination is identified as the most significant source of error. Of the known contamination incidents, most were detected by the NFI quality control system before the report was issued to the authorities, and thus did not lead to flawed decisions like false convictions. However in a very limited number of cases crucial errors were detected after the report was issued, sometimes with severe consequences. Many of these errors were made in the post-analytical phase. The error rates reported in this paper are useful for quality improvement and benchmarking, and contribute to an open research culture that promotes public trust. However, they are irrelevant in the context of a particular case. Here case-specific probabilities of undetected errors are needed. These should be reported, separately from the match probability, when requested by the court or when there are internal or external indications for error. It should also be made clear that there are various other issues to consider, like DNA transfer. Forensic statistical models, in particular Bayesian networks, may be useful to take the various uncertainties into account and demonstrate their effects on the evidential value of the forensic DNA results. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

Prevention of DNA contamination during forensic medical examinations in a clinical forensic medical service: A best practice implementation project.

PubMed

Lutz, Tasha

2015-01-01

Contamination of forensic specimens can have significant and detrimental effects on cases presented in court. In 2010 a wrongful conviction in Australia resulted in an inquiry with 25 recommendations to minimize the risk of DNA contamination of forensic specimens. DNA decontamination practices in a clinical forensic medical service currently attempt to comply with these recommendations. Evaluation of these practices has not been undertaken. The aim of this project was to audit the current DNA decontamination practices of forensic medical and nursing examiners in the forensic medical examination process and implement changes based on the audit findings. A re-audit following implementation would be undertaken to identify change and inform further research. The Joanna Briggs Institute's Practical Application of Clinical Evidence System and Getting Research into Practice were used as the audit tool in this project. A baseline audit was conducted; analysis of this audit process was then undertaken. Following education and awareness training targeted at clinicians, a re-audit was completed. There were a total of 24 audit criteria; the baseline audit reflected 20 of these criteria had 100% compliance. The remaining 4 audit criteria demonstrated compliance between 65% and 90%. Education and awareness training resulted in improved compliance in 2 of the 4 audit criteria, with the remaining 2 having unchanged compliance. The findings demonstrated that education and raising awareness can improve clinical practice; however there are also external factors outside the control of the clinicians that influence compliance with best practice.

Palaeomicrobiology meets forensic medicine: time as a fourth-dimension for the crime scene.

PubMed

Bazaj, A; Turrina, S; De Leo, D; Cornaglia, G

2015-03-01

The unrelenting progress of laboratory techniques is rapidly unleashing the huge potential of palaeomicrobiology. That bodies are often found in poor condition is common to both palaeomicrobiology and forensic medicine, and this might stimulate them towards a joint quest to extract reproducible data for reliable specimens.

Identification of feces by detection of Bacteroides genes.

PubMed

Nakanishi, Hiroaki; Shojo, Hideki; Ohmori, Takeshi; Hara, Masaaki; Takada, Aya; Adachi, Noboru; Saito, Kazuyuki

2013-01-01

In forensic science, the identification of feces is very important in a variety of crime investigations. However, no sensitive and simple fecal identification method using molecular biological techniques has been reported. Here, we focused on the fecal bacteria, Bacteroides uniformis, Bacteroides vulgatus and Bacteroides thetaiotaomicron, and developed a novel fecal identification method by detection of the gene sequences specific to these bacteria in various body (feces, blood, saliva, semen, urine, vaginal fluids and skin surfaces) and forensic (anal adhesions) specimens. Bacterial gene detection was performed by real-time PCR using a minor groove binding probe to amplify the RNA polymerase β-subunit gene of B. uniformis and B. vulgatus, and the α-1-6 mannanase gene of B. thetaiotaomicron. At least one of these bacteria was detected in the feces of 20 donors; the proportions of B. uniformis, B. vulgatus and B. thetaiotaomicron were 95, 85 and 60%, respectively. Bacteroides vulgatus was also detected in one of six vaginal fluid samples, but B. thetaiotaomicron and B. uniformis were not detected in body samples other than feces. Further, we applied this method to forensic specimens from 18 donors. Eighteen anal adhesions also contained at least one of three bacteria; B. uniformis, B. vulgatus and B. thetaiotaomicron were detected in 89, 78 and 56%, respectively, of the specimens. Thus, these bacteria were present at a high frequency in the fecal and forensic specimens, while either B. uniformis or B. vulgatus was detected in all samples. Therefore, B. uniformis and B. vulgatus represent more appropriate target species than B. thetaiotaomicron for the identification of fecal material. If B. vulgatus and/or B. uniformis are detected, it is likely that the sample contains feces. Taken together, our results suggest that the use of molecular biological techniques will aid the detection of feces in forensic practice, although it is possible that the samples contained both feces and vaginal fluid. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

Fast screening tests for the simultaneous detection of 11 drugs of abuse in urine specimens. A forensic epidemiology study of 28,298 cases in Tunisia.

PubMed

Moslah, B; Araoud, M; Nouioui, M A; Najjar, S; Amira, D; Ben Salah, N; Hedhili, A

2018-02-01

Forensic investigation performed on people suspected to be drug abusers covering all Tunisian cities was conducted by monitoring an epidemiological study of human urine samples surveying positive rates of consumption for drugs of abuse. The forensic investigations were conducted on a total of 28,298 arrested individuals suspected to be drug addicts during five years (January 2010-December 2015). An immunoassay screening tests to detect elevated levels of drugs classes in urine samples was performed. These screening assays provide a preliminary qualitative test result. Only positives urine specimens were analyzed with GC-MS for confirmation. Except for cannabis, the results showed insignificant number of positive cases for cocaine, ecstasy (MDMA) and amphetamine consumptions (<1%). Copyright © 2017 Elsevier B.V. All rights reserved.

Principles and procedures in forensic toxicology.

PubMed

Wyman, John F

2012-09-01

The principles and procedures employed in a modern forensic toxicology lab are detailed in this review. Aspects of Behavioral and Postmortem toxicology, including certification of analysts and accreditation of labs, chain of custody requirements, typical testing services provided, rationale for specimen selection, and principles of quality assurance are discussed. Interpretation of toxicology results in postmortem specimens requires the toxicologist and pathologist to be cognizant of drug-drug interactions, drug polymorphisms and pharmacogenomics, the gross signs of toxic pathology, postmortem redistribution, confirmation of systemic toxicity in suspected overdoses, the possibility of developed tolerance, and the effects of decomposition on drug concentration.

The HIrisPlex-S system for eye, hair and skin colour prediction from DNA: Introduction and forensic developmental validation.

PubMed

Chaitanya, Lakshmi; Breslin, Krystal; Zuñiga, Sofia; Wirken, Laura; Pośpiech, Ewelina; Kukla-Bartoszek, Magdalena; Sijen, Titia; Knijff, Peter de; Liu, Fan; Branicki, Wojciech; Kayser, Manfred; Walsh, Susan

2018-07-01

Forensic DNA Phenotyping (FDP), i.e. the prediction of human externally visible traits from DNA, has become a fast growing subfield within forensic genetics due to the intelligence information it can provide from DNA traces. FDP outcomes can help focus police investigations in search of unknown perpetrators, who are generally unidentifiable with standard DNA profiling. Therefore, we previously developed and forensically validated the IrisPlex DNA test system for eye colour prediction and the HIrisPlex system for combined eye and hair colour prediction from DNA traces. Here we introduce and forensically validate the HIrisPlex-S DNA test system (S for skin) for the simultaneous prediction of eye, hair, and skin colour from trace DNA. This FDP system consists of two SNaPshot-based multiplex assays targeting a total of 41 SNPs via a novel multiplex assay for 17 skin colour predictive SNPs and the previous HIrisPlex assay for 24 eye and hair colour predictive SNPs, 19 of which also contribute to skin colour prediction. The HIrisPlex-S system further comprises three statistical prediction models, the previously developed IrisPlex model for eye colour prediction based on 6 SNPs, the previous HIrisPlex model for hair colour prediction based on 22 SNPs, and the recently introduced HIrisPlex-S model for skin colour prediction based on 36 SNPs. In the forensic developmental validation testing, the novel 17-plex assay performed in full agreement with the Scientific Working Group on DNA Analysis Methods (SWGDAM) guidelines, as previously shown for the 24-plex assay. Sensitivity testing of the 17-plex assay revealed complete SNP profiles from as little as 63 pg of input DNA, equalling the previously demonstrated sensitivity threshold of the 24-plex HIrisPlex assay. Testing of simulated forensic casework samples such as blood, semen, saliva stains, of inhibited DNA samples, of low quantity touch (trace) DNA samples, and of artificially degraded DNA samples as well as concordance testing, demonstrated the robustness, efficiency, and forensic suitability of the new 17-plex assay, as previously shown for the 24-plex assay. Finally, we provide an update to the publically available HIrisPlex website https://hirisplex.erasmusmc.nl/, now allowing the estimation of individual probabilities for 3 eye, 4 hair, and 5 skin colour categories from HIrisPlex-S input genotypes. The HIrisPlex-S DNA test represents the first forensically validated tool for skin colour prediction, and reflects the first forensically validated tool for simultaneous eye, hair and skin colour prediction from DNA. Copyright © 2018 Elsevier B.V. All rights reserved.

Caseworker assessments of risk for recurrent maltreatment: association with case-specific risk factors and re-reports.

PubMed

Dorsey, Shannon; Mustillo, Sarah A; Farmer, Elizabeth M Z; Elbogen, Eric

2008-03-01

This article focuses on caseworkers' assessments of risk of maltreatment recurrence among families in contact with social services. Specifically, the article has two primary goals: (1) to examine the association between caseworkers' risk assessments and demographic, child, parent and family-level risk factors; and (2) to examine agreement between caseworkers' risk assessments and any subsequent report, or reports, of maltreatment. Data are from the baseline, 12-month, and 18-month assessments of the National Survey for Child and Adolescent Well-Being (NSCAW), a nationally representative sample of youth and families who were the subjects of allegations of maltreatment investigated by child welfare agencies. The sample consisted of a subset of NSCAW participants: cases with a report of child physical abuse or neglect who were not placed in out-of-home care (N=2,139). Analyses indicated that parent-level risk factors and a prior report of maltreatment were most strongly associated with caseworkers' assessments of risk for both physical abuse and neglect cases. A smaller set of factors, which varied by the type of maltreatment, were associated with a subsequent report of maltreatment. Despite some overlap in correlates of risk assessment and subsequent reports, analyses indicated that agreement between caseworkers' assessments of risk and re-reports was low. Findings suggest that although caseworkers' assessments were associated with a limited set of risk factors from the literature, few of these factors also were associated with a recurrent report of maltreatment. Correspondence between caseworkers' assessments of risk and a subsequent report of maltreatment was low, suggesting that considerable work may be needed to improve accuracy and identification of cases most at risk. This study provides information to assist caseworkers, administrators, and policymakers in thinking critically about risk assessment policies and procedures. Although caseworkers' assessments of risk were associated with some of the empirical predictors of recurrent maltreatment, their assessments were only slightly better than guessing. Agreement between caseworkers' risk assessments and actual subsequent reports was better for low-risk cases, but primarily because the majority of cases did not have a subsequent report during the study period. Clearly, considerable improvement in risk assessment is needed so that at-risk families can be better identified and the limited services available can be directed toward those most in need.

Direct amplification of casework bloodstains using the Promega PowerPlex(®) 21 PCR amplification system.

PubMed

Gray, Kerryn; Crowle, Damian; Scott, Pam

2014-09-01

A significant number of evidence items submitted to Forensic Science Service Tasmania (FSST) are blood swabs or bloodstained items. Samples from these items routinely undergo phenol:chloroform:isoamyl alcohol organic extraction and quantitative Polymerase Chain Reaction (qPCR) testing prior to PowerPlex(®) 21 amplification. This multi-step process has significant cost and timeframe implications in a fiscal climate of tightening government budgets, pressure towards improved operating efficiencies, and an increasing emphasis on rapid techniques better supporting intelligence-led policing. Direct amplification of blood and buccal cells on cloth and Whatman FTA™ card with PowerPlex(®) 21 has already been successfully implemented for reference samples, eliminating the requirement for sample pre-treatment. Scope for expanding this method to include less pristine casework blood swabs and samples from bloodstained items was explored in an endeavour to eliminate lengthy DNA extraction, purification and qPCR steps for a wider subset of samples. Blood was deposited onto a range of substrates including those historically found to inhibit STR amplification. Samples were collected with micro-punch, micro-swab, or both. The potential for further fiscal savings via reduced volume amplifications was assessed by amplifying all samples at full and reduced volume (25 and 13μL). Overall success rate data showed 80% of samples yielded a complete profile at reduced volume, compared to 78% at full volume. Particularly high success rates were observed for the blood on fabric/textile category with 100% of micro-punch samples yielding complete profiles at reduced volume and 85% at full volume. Following the success of this trial, direct amplification of suitable casework blood samples has been implemented at reduced volume. Significant benefits have been experienced, most noticeably where results from crucial items have been provided to police investigators prior to interview of suspects, and a coronial identification has been successfully completed in a short timeframe to avoid delay in the release of human remains to family members. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

Improved amplification results following episodes of failure to amplify at the Amelogenin Locus using PowerPlex® ESI 16 Fast System.

PubMed

Berlyne, Sigal; Oz, Carla; Einot, Naftaly; Avraham, Shlomit; Ram, Tanya; Goldberg, Miri D; Gafny, Ron

2017-07-01

In 2012 the Israel Police DNA Casework laboratory adopted the 16 STR PowerPlex ® ESI kit for routine use. The Promega Company updated this kit and developed the PowerPlex ® ESI 16 Fast System in which all autosomal primer pairs remained identical to the original set, except at the amelogenin site. The master mix was improved and optimized which allowed for direct, faster and more robust amplification. Prior to implementing the PowerPlex ® ESI 16 Fast System in our lab, we conducted a preliminary assay where 213 casework samples were amplified using the new kit. These samples had previously been extracted by one of two extraction kits employed by our lab. (the PrepFiler ExpressTM and PrepFiler BTATM Forensic DNA Extraction Kits). The amplification results from these samples were compared to samples amplified using the original PowerPlex ® ESI 16 kit. Multiple incidents of failure to amplify at the amelogenin locus were noted using the new system with the recommended protocol at a rate of 13% (28 of 213 samples). Experiments were performed to understand whether these amplification failures could be a result of primer binding site mutations, extraction method reagents and/or inhibitors. The conclusions reached following these experiments, in conjunction with consultation with the manufacturer, led to the trial of a modified amplification protocol where the suggested annealing temperature was reduced by 2 degrees. To evaluate the efficiency of this altered protocol, a comparison study was undertaken where 88 additional casework samples were chosen and amplified using both the modified 58°C and the recommended 60°C annealing temperatures. We concluded that the most effective method in our laboratory for achieving a consistent and balanced amplification at the amelogenin locus was to reduce the annealing temperature from the manufacturer's recommended 60°C to 58°C. This modification resulted in a reduction of the failure to amplify at the amelogenin locus from 13% (28/213) to 1.1% (1/88) without any observed changes to the autosomal STR amplification results. Copyright © 2017 Elsevier B.V. All rights reserved.

X-ray computed tomography datasets for forensic analysis of vertebrate fossils.

PubMed

Rowe, Timothy B; Luo, Zhe-Xi; Ketcham, Richard A; Maisano, Jessica A; Colbert, Matthew W

2016-06-07

We describe X-ray computed tomography (CT) datasets from three specimens recovered from Early Cretaceous lakebeds of China that illustrate the forensic interpretation of CT imagery for paleontology. Fossil vertebrates from thinly bedded sediments often shatter upon discovery and are commonly repaired as amalgamated mosaics grouted to a solid backing slab of rock or plaster. Such methods are prone to inadvertent error and willful forgery, and once required potentially destructive methods to identify mistakes in reconstruction. CT is an efficient, nondestructive alternative that can disclose many clues about how a specimen was handled and repaired. These annotated datasets illustrate the power of CT in documenting specimen integrity and are intended as a reference in applying CT more broadly to evaluating the authenticity of comparable fossils.

X-ray computed tomography datasets for forensic analysis of vertebrate fossils

PubMed Central

Rowe, Timothy B.; Luo, Zhe-Xi; Ketcham, Richard A.; Maisano, Jessica A.; Colbert, Matthew W.

2016-01-01

We describe X-ray computed tomography (CT) datasets from three specimens recovered from Early Cretaceous lakebeds of China that illustrate the forensic interpretation of CT imagery for paleontology. Fossil vertebrates from thinly bedded sediments often shatter upon discovery and are commonly repaired as amalgamated mosaics grouted to a solid backing slab of rock or plaster. Such methods are prone to inadvertent error and willful forgery, and once required potentially destructive methods to identify mistakes in reconstruction. CT is an efficient, nondestructive alternative that can disclose many clues about how a specimen was handled and repaired. These annotated datasets illustrate the power of CT in documenting specimen integrity and are intended as a reference in applying CT more broadly to evaluating the authenticity of comparable fossils. PMID:27272251

Pattern Recognition-Assisted Infrared Library Searching of the Paint Data Query Database to Enhance Lead Information from Automotive Paint Trace Evidence.

PubMed

Lavine, Barry K; White, Collin G; Allen, Matthew D; Weakley, Andrew

2017-03-01

Multilayered automotive paint fragments, which are one of the most complex materials encountered in the forensic science laboratory, provide crucial links in criminal investigations and prosecutions. To determine the origin of these paint fragments, forensic automotive paint examiners have turned to the paint data query (PDQ) database, which allows the forensic examiner to compare the layer sequence and color, texture, and composition of the sample to paint systems of the original equipment manufacturer (OEM). However, modern automotive paints have a thin color coat and this layer on a microscopic fragment is often too thin to obtain accurate chemical and topcoat color information. A search engine has been developed for the infrared (IR) spectral libraries of the PDQ database in an effort to improve discrimination capability and permit quantification of discrimination power for OEM automotive paint comparisons. The similarity of IR spectra of the corresponding layers of various records for original finishes in the PDQ database often results in poor discrimination using commercial library search algorithms. A pattern recognition approach employing pre-filters and a cross-correlation library search algorithm that performs both a forward and backward search has been used to significantly improve the discrimination of IR spectra in the PDQ database and thus improve the accuracy of the search. This improvement permits inter-comparison of OEM automotive paint layer systems using the IR spectra alone. Such information can serve to quantify the discrimination power of the original automotive paint encountered in casework and further efforts to succinctly communicate trace evidence to the courts.

Elder Fraud and Financial Exploitation: Application of Routine Activity Theory.

PubMed

DeLiema, Marguerite

2017-03-10

Elder financial exploitation, committed by individuals in positions of trust, and elder fraud, committed by predatory strangers, are two forms of financial victimization that target vulnerable older adults. This study analyzes differences between fraud and financial exploitation victims and tests routine activity theory as a contextual model for victimization. Routine activity theory predicts that criminal opportunities arise when a motivated offender and suitable target meet in the absence of capable guardians. Fifty-three financial exploitation and fraud cases were sampled from an elder abuse forensic center. Data include law enforcement and caseworker investigation reports, victim medical records, perpetrator demographic information, and forensic assessments of victim health and cognitive functioning. Fraud and financial exploitation victims performed poorly on tests of cognitive functioning and financial decision making administered by a forensic neuropsychologist following the allegations. Based on retrospective record review, there were few significant differences in physical health and cognitive functioning at the time victims' assets were taken, although their social contexts were different. Significantly more fraud victims were childless compared with financial exploitation victims. Fraud perpetrators took advantage of elders when they had no trustworthy friends or relatives to safeguard their assets. Findings support an adapted routine activity theory as a contextual model for financial victimization. Fraud most often occurred when a vulnerable elder was solicited by a financial predator in the absence of capable guardians. Prevention efforts should focus on reducing social isolation to enhance protection. © The Author 2017. Published by Oxford University Press on behalf of The Gerontological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

DART-MS: A New Analytical Technique for Forensic Paint Analysis.

PubMed

Marić, Mark; Marano, James; Cody, Robert B; Bridge, Candice

2018-06-05

Automotive paint evidence is one of the most significant forms of evidence obtained in automotive-related incidents. Therefore, the analysis of automotive paint evidence is imperative in forensic casework. Most analytical schemes for automotive paint characterization involve optical microscopy, followed by infrared spectroscopy and pyrolysis-gas chromatography mass spectrometry ( py-GCMS) if required. The main drawback with py-GCMS, aside from its destructive nature, is that this technique is relatively time intensive in comparison to other techniques. Direct analysis in real-time-time-of-flight mass spectrometry (DART-TOFMS) may provide an alternative to py-GCMS, as the rapidity of analysis and minimal sample preparation affords a significant advantage. In this study, automotive clear coats from four vehicles were characterized by DART-TOFMS and a standard py-GCMS protocol. Principal component analysis was utilized to interpret the resultant data and suggested the two techniques provided analogous sample discrimination. Moreover, in some instances DART-TOFMS was able to identify components not observed by py-GCMS and vice versa, which indicates that the two techniques may provide complementary information. Additionally, a thermal desorption/pyrolysis DART-TOFMS methodology was also evaluated to characterize the intact paint chips from the vehicles to ascertain if the linear temperature gradient provided additional discriminatory information. All the paint samples were able to be discriminated based on the distinctive thermal desorption plots afforded from this technique, which may also be utilized for sample discrimination. On the basis of the results, DART-TOFMS may provide an additional tool to the forensic paint examiner.

Palaeomicrobiology meets forensic medicine: time as a fourth-dimension for the crime scene

PubMed Central

Bazaj, A.; Turrina, S.; De Leo, D.; Cornaglia, G.

2015-01-01

The unrelenting progress of laboratory techniques is rapidly unleashing the huge potential of palaeomicrobiology. That bodies are often found in poor condition is common to both palaeomicrobiology and forensic medicine, and this might stimulate them towards a joint quest to extract reproducible data for reliable specimens. PMID:25830027

A Universal Method for Species Identification of Mammals Utilizing Next Generation Sequencing for the Analysis of DNA Mixtures

PubMed Central

Tillmar, Andreas O.; Dell'Amico, Barbara; Welander, Jenny; Holmlund, Gunilla

2013-01-01

Species identification can be interesting in a wide range of areas, for example, in forensic applications, food monitoring and in archeology. The vast majority of existing DNA typing methods developed for species determination, mainly focuses on a single species source. There are, however, many instances where all species from mixed sources need to be determined, even when the species in minority constitutes less than 1 % of the sample. The introduction of next generation sequencing opens new possibilities for such challenging samples. In this study we present a universal deep sequencing method using 454 GS Junior sequencing of a target on the mitochondrial gene 16S rRNA. The method was designed through phylogenetic analyses of DNA reference sequences from more than 300 mammal species. Experiments were performed on artificial species-species mixture samples in order to verify the method’s robustness and its ability to detect all species within a mixture. The method was also tested on samples from authentic forensic casework. The results showed to be promising, discriminating over 99.9 % of mammal species and the ability to detect multiple donors within a mixture and also to detect minor components as low as 1 % of a mixed sample. PMID:24358309

Biometrics from the carbon isotope ratio analysis of amino acids in human hair.

PubMed

Jackson, Glen P; An, Yan; Konstantynova, Kateryna I; Rashaid, Ayat H B

2015-01-01

This study compares and contrasts the ability to classify individuals into different grouping factors through either bulk isotope ratio analysis or amino-acid-specific isotope ratio analysis of human hair. Using LC-IRMS, we measured the isotope ratios of 14 amino acids in hair proteins independently, and leucine/isoleucine as a co-eluting pair, to provide 15 variables for classification. Multivariate analysis confirmed that the essential amino acids and non-essential amino acids were mostly independent variables in the classification rules, thereby enabling the separation of dietary factors of isotope intake from intrinsic or phenotypic factors of isotope fractionation. Multivariate analysis revealed at least two potential sources of non-dietary factors influencing the carbon isotope ratio values of the amino acids in human hair: body mass index (BMI) and age. These results provide evidence that compound-specific isotope ratio analysis has the potential to go beyond region-of-origin or geospatial movements of individuals-obtainable through bulk isotope measurements-to the provision of physical and characteristic traits about the individuals, such as age and BMI. Further development and refinement, for example to genetic, metabolic, disease and hormonal factors could ultimately be of great assistance in forensic and clinical casework. Copyright © 2014 Forensic Science Society. Published by Elsevier Ireland Ltd. All rights reserved.

A global analysis of Y-chromosomal haplotype diversity for 23 STR loci

PubMed Central

Purps, Josephine; Siegert, Sabine; Willuweit, Sascha; Nagy, Marion; Alves, Cíntia; Salazar, Renato; Angustia, Sheila M.T.; Santos, Lorna H.; Anslinger, Katja; Bayer, Birgit; Ayub, Qasim; Wei, Wei; Xue, Yali; Tyler-Smith, Chris; Bafalluy, Miriam Baeta; Martínez-Jarreta, Begoña; Egyed, Balazs; Balitzki, Beate; Tschumi, Sibylle; Ballard, David; Court, Denise Syndercombe; Barrantes, Xinia; Bäßler, Gerhard; Wiest, Tina; Berger, Burkhard; Niederstätter, Harald; Parson, Walther; Davis, Carey; Budowle, Bruce; Burri, Helen; Borer, Urs; Koller, Christoph; Carvalho, Elizeu F.; Domingues, Patricia M.; Chamoun, Wafaa Takash; Coble, Michael D.; Hill, Carolyn R.; Corach, Daniel; Caputo, Mariela; D’Amato, Maria E.; Davison, Sean; Decorte, Ronny; Larmuseau, Maarten H.D.; Ottoni, Claudio; Rickards, Olga; Lu, Di; Jiang, Chengtao; Dobosz, Tadeusz; Jonkisz, Anna; Frank, William E.; Furac, Ivana; Gehrig, Christian; Castella, Vincent; Grskovic, Branka; Haas, Cordula; Wobst, Jana; Hadzic, Gavrilo; Drobnic, Katja; Honda, Katsuya; Hou, Yiping; Zhou, Di; Li, Yan; Hu, Shengping; Chen, Shenglan; Immel, Uta-Dorothee; Lessig, Rüdiger; Jakovski, Zlatko; Ilievska, Tanja; Klann, Anja E.; García, Cristina Cano; de Knijff, Peter; Kraaijenbrink, Thirsa; Kondili, Aikaterini; Miniati, Penelope; Vouropoulou, Maria; Kovacevic, Lejla; Marjanovic, Damir; Lindner, Iris; Mansour, Issam; Al-Azem, Mouayyad; Andari, Ansar El; Marino, Miguel; Furfuro, Sandra; Locarno, Laura; Martín, Pablo; Luque, Gracia M.; Alonso, Antonio; Miranda, Luís Souto; Moreira, Helena; Mizuno, Natsuko; Iwashima, Yasuki; Neto, Rodrigo S. Moura; Nogueira, Tatiana L.S.; Silva, Rosane; Nastainczyk-Wulf, Marina; Edelmann, Jeanett; Kohl, Michael; Nie, Shengjie; Wang, Xianping; Cheng, Baowen; Núñez, Carolina; Pancorbo, Marian Martínez de; Olofsson, Jill K.; Morling, Niels; Onofri, Valerio; Tagliabracci, Adriano; Pamjav, Horolma; Volgyi, Antonia; Barany, Gusztav; Pawlowski, Ryszard; Maciejewska, Agnieszka; Pelotti, Susi; Pepinski, Witold; Abreu-Glowacka, Monica; Phillips, Christopher; Cárdenas, Jorge; Rey-Gonzalez, Danel; Salas, Antonio; Brisighelli, Francesca; Capelli, Cristian; Toscanini, Ulises; Piccinini, Andrea; Piglionica, Marilidia; Baldassarra, Stefania L.; Ploski, Rafal; Konarzewska, Magdalena; Jastrzebska, Emila; Robino, Carlo; Sajantila, Antti; Palo, Jukka U.; Guevara, Evelyn; Salvador, Jazelyn; Ungria, Maria Corazon De; Rodriguez, Jae Joseph Russell; Schmidt, Ulrike; Schlauderer, Nicola; Saukko, Pekka; Schneider, Peter M.; Sirker, Miriam; Shin, Kyoung-Jin; Oh, Yu Na; Skitsa, Iulia; Ampati, Alexandra; Smith, Tobi-Gail; Calvit, Lina Solis de; Stenzl, Vlastimil; Capal, Thomas; Tillmar, Andreas; Nilsson, Helena; Turrina, Stefania; De Leo, Domenico; Verzeletti, Andrea; Cortellini, Venusia; Wetton, Jon H.; Gwynne, Gareth M.; Jobling, Mark A.; Whittle, Martin R.; Sumita, Denilce R.; Wolańska-Nowak, Paulina; Yong, Rita Y.Y.; Krawczak, Michael; Nothnagel, Michael; Roewer, Lutz

2014-01-01

In a worldwide collaborative effort, 19,630 Y-chromosomes were sampled from 129 different populations in 51 countries. These chromosomes were typed for 23 short-tandem repeat (STR) loci (DYS19, DYS389I, DYS389II, DYS390, DYS391, DYS392, DYS393, DYS385ab, DYS437, DYS438, DYS439, DYS448, DYS456, DYS458, DYS635, GATAH4, DYS481, DYS533, DYS549, DYS570, DYS576, and DYS643) and using the PowerPlex Y23 System (PPY23, Promega Corporation, Madison, WI). Locus-specific allelic spectra of these markers were determined and a consistently high level of allelic diversity was observed. A considerable number of null, duplicate and off-ladder alleles were revealed. Standard single-locus and haplotype-based parameters were calculated and compared between subsets of Y-STR markers established for forensic casework. The PPY23 marker set provides substantially stronger discriminatory power than other available kits but at the same time reveals the same general patterns of population structure as other marker sets. A strong correlation was observed between the number of Y-STRs included in a marker set and some of the forensic parameters under study. Interestingly a weak but consistent trend toward smaller genetic distances resulting from larger numbers of markers became apparent. PMID:24854874

Interlaboratory comparison of autoradiographic DNA profiling measurements: precision and concordance.

PubMed

Duewer, D L; Lalonde, S A; Aubin, R A; Fourney, R M; Reeder, D J

1998-05-01

Knowledge of the expected uncertainty in restriction fragment length polymorphism (RFLP) measurements is required for confident exchange of such data among different laboratories. The total measurement uncertainty among all Technical Working Group for DNA Analysis Methods laboratories has previously been characterized and found to be acceptably small. Casework cell line control measurements provided by six Royal Canadian Mounted Police (RCMP) and 30 U.S. commercial, local, state, and Federal forensic laboratories enable quantitative determination of the within-laboratory precision and among-laboratory concordance components of measurement uncertainty typical of both sets of laboratories. Measurement precision is the same in the two countries for DNA fragments of size 1000 base pairs (bp) to 10,000 bp. However, the measurement concordance among the RCMP laboratories is clearly superior to that within the U.S. forensic community. This result is attributable to the use of a single analytical protocol in all RCMP laboratories. Concordance among U.S. laboratories cannot be improved through simple mathematical adjustments. Community-wide efforts focused on improved concordance may be the most efficient mechanism for further reduction of among-laboratory RFLP measurement uncertainty, should the resources required to fully evaluate potential cross-jurisdictional matches become burdensome as the number of RFLP profiles on record increases.

Pilot-Reported Beta-Blockers Identified by Forensic Toxicology Analysis of Postmortem Specimens

DOT National Transportation Integrated Search

2017-01-01

This study compared beta-blockers reported by pilots with the medications found by postmortem toxicology analysis of specimens received from fatal aviation accidents between 1999 and 2015. Several studies have compared drugs using the standard approa...

DNA-based identification of forensically important species of Sarcophagidae (Insecta: Diptera) from Rio de Janeiro, Brazil.

PubMed

Napoleão, K S; Mello-Patiu, C A; Oliveira-Costa, J; Takiya, D M; Silva, R; Moura-Neto, R S

2016-05-06

Sarcophagidae, or flesh flies, are of great importance in forensic entomology, but their effective application requires precise taxonomic identification, which relies almost exclusively on characteristics of the male genitalia. Given that female flies and larvae are most abundant in animal carcasses or on corpses, precise morphological identification can be difficult; therefore, DNA sequencing can be an additional tool for use in taxonomic identification. This paper analyzes part of the mitochondrial cytochrome c oxidase subunit I (COI) gene from three Sarcophagidae species of forensic importance in the City of Rio de Janeiro: Oxysarcodexia fluminensis, Peckia chrysostoma, and Peckia intermutans. COI fragments of 400 bp from 36 specimens of these three species were sequenced. No intraspecific differences were found among specimens of O. fluminensis, but P. chrysostoma and P. intermutans each had two haplotypes, ranging from 0 to 0.7%. The interspecific divergence was 8.5-11.6%, corroborating previously reported findings.

Social Case-work in General Practice: An Alternative Approach

PubMed Central

Ratoff, L.; Pearson, Barbara

1970-01-01

During a two-year period a senior case-worker was seconded by a voluntary family case-work agency, the Liverpool Personal Service Society, to work with three general practitioners. The commonest reasons for referral of the 157 new patients to the social worker over this study period were extreme poverty; housing, matrimonial, and psychiatric problems; and problems of fatherless families. The successful and valuable co-operation between the general practitioners, case-worker, and various specialist professional and financial services of the Society have proved that a professional social worker has an important role in the general-practice team. PMID:5420213

Aviation accident forensic assessment : comprehensive single-extraction urine screening procedure : final report.

DOT National Transportation Integrated Search

1996-05-01

This paper describes a new single extraction screening procedure that was developed to identify as many drugs as possible in urine, with minimal effort and cost. Urine specimens are hydrolyzed and the specimen is then extracted using commercially pur...

Caseworker Assessments of Risk for Recurrent Maltreatment: Association with Case-Specific Risk Factors and Re-Reports

ERIC Educational Resources Information Center

Dorsey, Shannon; Mustillo, Sarah A.; Farmer, Elizabeth M. Z.; Elbogen, Eric

2008-01-01

Objective: This article focuses on caseworkers' assessments of risk of maltreatment recurrence among families in contact with social services. Specifically, the article has two primary goals: (1) to examine the association between caseworkers' risk assessments and demographic, child, parent and family-level risk factors; and (2) to examine…

Reducing turnover is not enough: The need for proficient organizational cultures to support positive youth outcomes in child welfare

PubMed Central

Glisson, Charles

2013-01-01

Objective High caseworker turnover has been identified as a factor in the poor outcomes of child welfare services. However, almost no empirical research has examined the relationship between caseworker turnover and youth outcomes in child welfare systems and there is an important knowledge gap regarding whether, and how, caseworker turnover relates to outcomes for youth. We hypothesized that the effects of caseworker turnover are moderated by organizational culture such that reduced caseworker turnover is only associated with improved youth outcomes in organizations with proficient cultures. Methods The study applied hierarchical linear models (HLM) analysis to the second National Survey of Child and Adolescent Well-being (NSCAW II) with a U.S. nationwide sample of 2,346 youth aged 1.5- to 18-years-old and 1,544 caseworkers in 73 child welfare agencies. Proficient organizational culture was measured by caseworkers’ responses to the Organizational Social Context (OSC) measure; staff turnover was reported by the agencies’ directors; and youth outcomes were measured as total problems in psychosocial functioning with the Child Behavior Checklist (CBCL) completed by the youths’ caregivers at intake and at 18 month follow-up. Results The association between caseworker turnover and youth outcomes was moderated by organizational culture. Youth outcomes were improved with lower staff turnover in proficient organizational cultures and the best outcomes occurred in organizations with low turnover and high proficiency. Conclusions To be successful, efforts to improve child welfare services by lowering staff turnover must also create proficient cultures that expect caseworkers to be competent and responsive to the needs of the youth and families they serve. PMID:24273363

EMPOP-quality mtDNA control region sequences from Kashmiri of Azad Jammu & Kashmir, Pakistan.

PubMed

Rakha, Allah; Peng, Min-Sheng; Bi, Rui; Song, Jiao-Jiao; Salahudin, Zeenat; Adan, Atif; Israr, Muhammad; Yao, Yong-Gang

2016-11-01

The mitochondrial DNA (mtDNA) control region (nucleotide position 16024-576) sequences were generated through Sanger sequencing method for 317 self-identified Kashmiris from all districts of Azad Jammu & Kashmir Pakistan. The population sample set showed a total of 251 haplotypes, with a relatively high haplotype diversity (0.9977) and a low random match probability (0.54%). The containing matrilineal lineages belonging to three different phylogeographic origins of Western Eurasian (48.9%), South Asian (47.0%) and East Asian (4.1%). The present study was compared to previous data from Pakistan and other worldwide populations (Central Asia, Western Asia, and East & Southeast Asia). The dataset is made available through EMPOP under accession number EMP00679 and will serve as an mtDNA reference database in forensic casework in Pakistan. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Teaching artificial intelligence to read electropherograms.

PubMed

Taylor, Duncan; Powers, David

2016-11-01

Electropherograms are produced in great numbers in forensic DNA laboratories as part of everyday criminal casework. Before the results of these electropherograms can be used they must be scrutinised by analysts to determine what the identified data tells us about the underlying DNA sequences and what is purely an artefact of the DNA profiling process. A technique that lends itself well to such a task of classification in the face of vast amounts of data is the use of artificial neural networks. These networks, inspired by the workings of the human brain, have been increasingly successful in analysing large datasets, performing medical diagnoses, identifying handwriting, playing games, or recognising images. In this work we demonstrate the use of an artificial neural network which we train to 'read' electropherograms and show that it can generalise to unseen profiles. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Mitochondrial DNA typing from human axillary, pubic and head hair shafts - success rates and sequence comparisons.

PubMed

Pfeiffer, H; Hühne, J; Ortmann, C; Waterkamp, K; Brinkmann, B

1999-01-01

The analysis of mitochondrial DNA (mtDNA) from shed hairs has gained high importance in forensic casework since telogen hairs are one of the most common types of evidence left at the crime scene. In this systematic study of hair shafts from 20 individuals, the correlation of mtDNA recovery with hair morphology (length, diameter, volume, colour), with sex, and with body localisation (head, armpit, pubis) was investigated. The highest average success rate of hypervariable region 1 (HV 1) sequencing was found in head hair shafts (75%) followed by pubic (66%) and axillary hair shafts (52%). No statistically significant correlation between morphological parameters or sex and the success rate of sequencing was found. MtDNA sequences of buccal cells, head, pubic and axillary hair shafts did not show intraindividual differences. Heteroplasmic base positions were observed neither in the hair shafts nor in control samples of buccal cells.

Pigment phenotype and biogeographical ancestry from ancient skeletal remains: inferences from multiplexed autosomal SNP analysis.

PubMed

Bouakaze, Caroline; Keyser, Christine; Crubézy, Eric; Montagnon, Daniel; Ludes, Bertrand

2009-07-01

In the present study, a multiplexed genotyping assay for ten single nucleotide polymorphisms (SNPs) located within six pigmentation candidate genes was developed on modern biological samples and applied to DNA retrieved from 25 archeological human remains from southern central Siberia dating from the Bronze and Iron Ages. SNP genotyping was successful for the majority of ancient samples and revealed that most probably had typical European pigment features, i.e., blue or green eye color, light hair color and skin type, and were likely of European individual ancestry. To our knowledge, this study reports for the first time the multiplexed typing of autosomal SNPs on aged and degraded DNA. By providing valuable information on pigment traits of an individual and allowing individual biogeographical ancestry estimation, autosomal SNP typing can improve ancient DNA studies and aid human identification in some forensic casework situations when used to complement conventional molecular markers.

Developmental validation of the MiSeq FGx Forensic Genomics System for Targeted Next Generation Sequencing in Forensic DNA Casework and Database Laboratories.

PubMed

Jäger, Anne C; Alvarez, Michelle L; Davis, Carey P; Guzmán, Ernesto; Han, Yonmee; Way, Lisa; Walichiewicz, Paulina; Silva, David; Pham, Nguyen; Caves, Glorianna; Bruand, Jocelyne; Schlesinger, Felix; Pond, Stephanie J K; Varlaro, Joe; Stephens, Kathryn M; Holt, Cydne L

2017-05-01

Human DNA profiling using PCR at polymorphic short tandem repeat (STR) loci followed by capillary electrophoresis (CE) size separation and length-based allele typing has been the standard in the forensic community for over 20 years. Over the last decade, Next-Generation Sequencing (NGS) matured rapidly, bringing modern advantages to forensic DNA analysis. The MiSeq FGx™ Forensic Genomics System, comprised of the ForenSeq™ DNA Signature Prep Kit, MiSeq FGx™ Reagent Kit, MiSeq FGx™ instrument and ForenSeq™ Universal Analysis Software, uses PCR to simultaneously amplify up to 231 forensic loci in a single multiplex reaction. Targeted loci include Amelogenin, 27 common, forensic autosomal STRs, 24 Y-STRs, 7 X-STRs and three classes of single nucleotide polymorphisms (SNPs). The ForenSeq™ kit includes two primer sets: Amelogenin, 58 STRs and 94 identity informative SNPs (iiSNPs) are amplified using DNA Primer Set A (DPMA; 153 loci); if a laboratory chooses to generate investigative leads using DNA Primer Set B, amplification is targeted to the 153 loci in DPMA plus 22 phenotypic informative (piSNPs) and 56 biogeographical ancestry SNPs (aiSNPs). High-resolution genotypes, including detection of intra-STR sequence variants, are semi-automatically generated with the ForenSeq™ software. This system was subjected to developmental validation studies according to the 2012 Revised SWGDAM Validation Guidelines. A two-step PCR first amplifies the target forensic STR and SNP loci (PCR1); unique, sample-specific indexed adapters or "barcodes" are attached in PCR2. Approximately 1736 ForenSeq™ reactions were analyzed. Studies include DNA substrate testing (cotton swabs, FTA cards, filter paper), species studies from a range of nonhuman organisms, DNA input sensitivity studies from 1ng down to 7.8pg, two-person human DNA mixture testing with three genotype combinations, stability analysis of partially degraded DNA, and effects of five commonly encountered PCR inhibitors. Calculations from ForenSeq™ STR and SNP repeatability and reproducibility studies (1ng template) indicate 100.0% accuracy of the MiSeq FGx™ System in allele calling relative to CE for STRs (1260 samples), and >99.1% accuracy relative to bead array typing for SNPs (1260 samples for iiSNPs, 310 samples for aiSNPs and piSNPs), with >99.0% and >97.8% precision, respectively. Call rates of >99.0% were observed for all STRs and SNPs amplified with both ForenSeq™ primer mixes. Limitations of the MiSeq FGx™ System are discussed. Results described here demonstrate that the MiSeq FGx™ System meets forensic DNA quality assurance guidelines with robust, reliable, and reproducible performance on samples of various quantities and qualities. Copyright © 2017 The Authors. Published by Elsevier B.V. All rights reserved.

Isolation and genetic analysis of pure cells from forensic biological mixtures: The precision of a digital approach.

PubMed

Fontana, F; Rapone, C; Bregola, G; Aversa, R; de Meo, A; Signorini, G; Sergio, M; Ferrarini, A; Lanzellotto, R; Medoro, G; Giorgini, G; Manaresi, N; Berti, A

2017-07-01

Latest genotyping technologies allow to achieve a reliable genetic profile for the offender identification even from extremely minute biological evidence. The ultimate challenge occurs when genetic profiles need to be retrieved from a mixture, which is composed of biological material from two or more individuals. In this case, DNA profiling will often result in a complex genetic profile, which is then subject matter for statistical analysis. In principle, when more individuals contribute to a mixture with different biological fluids, their single genetic profiles can be obtained by separating the distinct cell types (e.g. epithelial cells, blood cells, sperm), prior to genotyping. Different approaches have been investigated for this purpose, such as fluorescent-activated cell sorting (FACS) or laser capture microdissection (LCM), but currently none of these methods can guarantee the complete separation of different type of cells present in a mixture. In other fields of application, such as oncology, DEPArray™ technology, an image-based, microfluidic digital sorter, has been widely proven to enable the separation of pure cells, with single-cell precision. This study investigates the applicability of DEPArray™ technology to forensic samples analysis, focusing on the resolution of the forensic mixture problem. For the first time, we report here the development of an application-specific DEPArray™ workflow enabling the detection and recovery of pure homogeneous cell pools from simulated blood/saliva and semen/saliva mixtures, providing full genetic match with genetic profiles of corresponding donors. In addition, we assess the performance of standard forensic methods for DNA quantitation and genotyping on low-count, DEPArray™-isolated cells, showing that pure, almost complete profiles can be obtained from as few as ten haploid cells. Finally, we explore the applicability in real casework samples, demonstrating that the described approach provides complete separation of cells with outstanding precision. In all examined cases, DEPArray™ technology proves to be a groundbreaking technology for the resolution of forensic biological mixtures, through the precise isolation of pure cells for an incontrovertible attribution of the obtained genetic profiles. Copyright © 2017 The Authors. Published by Elsevier B.V. All rights reserved.

Validation studies in forensic odontology - Part 1: Accuracy of radiographic matching.

PubMed

Page, Mark; Lain, Russell; Kemp, Richard; Taylor, Jane

2018-05-01

As part of a series of studies aimed at validating techniques in forensic odontology, this study aimed to validate the accuracy of ante-mortem (AM)/postmortem (PM) radiographic matching by dentists and forensic odontologists. This study used a web-based interface with 50 pairs of AM and PM radiographs from real casework, at varying degrees of difficulty. Participants were shown both radiographs as a pair and initially asked to decide if they represented the same individual using a yes/no binary choice forced-decision. Participants were asked to assess their level of confidence in their decision, and to make a conclusion using one of the ABFO (American Board of Forensic Odontology), INTERPOL (International Criminal Police Organisation) and DVISys™ (DVI System International, Plass Data Software) identification scale degrees. The mean false-positive rate using the binary choice scale was 12%. Overall accuracy was 89% using this model, however, 13% of participants scored below 80%. Only 25% of participants accurately answered yes or no >90% of the time, with no individual making the correct yes/no decision for all 50 pairs of radiographs. Non-odontologists (lay participants) scored poorly, with a mean accuracy of only 60%. Use of the graded ABFO, DVISYS and INTERPOL scales resulted in general improvements in performance, with the false-positive and false-negative rates falling to approximately 2% overall. Inter-examiner agreement in assigning scale degrees was good (ICC=0.64), however there was little correlation between confidence and both accuracy or agreement among practitioners. These results suggest that use of a non-binary scale is supported over a match/non-match call as it reduces the frequency of false positives and negatives. The use of the terms "possible" and "insufficient information" in the same scale appears to create confusion, reducing inter-examiner agreement. The lack of agreement between higher-performing and lower-performing groups suggests that there is an inconsistency in the cognitive processes used to determine similarity between radiographs. Copyright © 2017 The Chartered Society of Forensic Sciences. All rights reserved.

Developmental validation of a custom panel including 273 SNPs for forensic application using Ion Torrent PGM.

PubMed

Zhang, Suhua; Bian, Yingnan; Chen, Anqi; Zheng, Hancheng; Gao, Yuzhen; Hou, Yiping; Li, Chengtao

2017-03-01

Utilizing massively parallel sequencing (MPS) technology for SNP testing in forensic genetics is becoming attractive because of the shortcomings of STR markers, such as their high mutation rates and disadvantages associated with the current PCR-CE method as well as its limitations regarding multiplex capabilities. MPS offers the potential to genotype hundreds to thousands of SNPs from multiple samples in a single experimental run. In this study, we designed a customized SNP panel that includes 273 forensically relevant identity SNPs chosen from SNPforID, IISNP, and the HapMap database as well as previously related studies and evaluated the levels of genotyping precision, sequence coverage, sensitivity and SNP performance using the Ion Torrent PGM. In a concordant study of the custom MPS-SNP panel, only four MPS callings were missing due to coverage reads that were too low (<20), whereas the others were fully concordant with Sanger's sequencing results across the two control samples, that is, 9947A and 9948. The analyses indicated a balanced coverage among the included loci, with the exception of the 16 SNPs that were used to detect an inconsistent allele balance and/or lower coverage reads among 50 tested individuals from the Chinese HAN population and the above controls. With the exception of the 16 poorly performing SNPs, the sequence coverage obtained was extensive for the bulk of the SNPs, and only three Y-SNPs (rs16980601, rs11096432, rs3900) showed a mean coverage below 1000. Analyses of the dilution series of control DNA 9948 yielded reproducible results down to 1ng of DNA input. In addition, we provide an analysis tool for automated data quality control and genotyping checks, and we conclude that the SNP targets are polymorphic and independent in the Chinese HAN population. In summary, the evaluation of the sensitivity, accuracy and genotyping performance provides strong support for the application of MPS technology in forensic SNP analysis, and the assay offers a straightforward sample-to-genotype workflow that could be beneficial in forensic casework with respect to both individual identification and complex kinship issues. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Investigation of gunshot residue patterns using milli-XRF-techniques: first experiences in casework

NASA Astrophysics Data System (ADS)

Schumacher, Rüdiger; Barth, Martin; Neimke, Dieter; Niewöhner, Ludwig

2010-06-01

The investigation of gunshot residue (GSR) patterns for shooting range estimation is usually based on visualizing the lead, copper, or nitrocellulose distributions on targets like fabric or adhesive tape by chemographic color tests. The method usually provides good results but has its drawbacks when it comes to the examination of ammunition containing lead-free primers or bloody clothing. A milli-X-ray fluorescence (m-XRF) spectrometer with a large motorized stage can help to circumvent these problems allowing the acquisition of XRF mappings of relatively large areas (up to 20 x 20 cm) in millimeter resolution within reasonable time (2-10 hours) for almost all elements. First experiences in GSR casework at the Forensic Science Institute of the Bundeskriminalamt (BKA) have shown, that m-XRF is a useful supplementation for conventional methods in shooting ranges estimation, which helps if there are problems in transferring a GSR pattern to secondary targets (e.g. bloody or stained garments) or if there is no suitable color test available for the element of interest. The resulting elemental distributions are a good estimate for the shooting range and can be evaluated by calculating radial distributions or integrated count rates of irregular shaped regions like pieces of human skin which are too small to be investigated with a conventional WD-XRF spectrometer. Beside a mapping mode the milli-XRF offers also point and line scan modes which can also be utilized in gunshot crime investigations as a quick survey tool to identify bullet holes based on the elements present in the wipe ring.

Forensic and population genetic analyses of eighteen non-CODIS miniSTR loci in the Korean population.

PubMed

Jin, Han Jun; Kim, Ki Cheol; Yoon, Cha Eun; Kim, Wook

2013-11-01

We analyzed the variation of eighteen miniSTR loci in 411 randomly chosen individuals from Korea to increase the probability that a degraded sample can be typed, as well as to provide an expanded and reliable population database. Six multiplex PCR systems were developed (multiplex I: D1S1677, D2S441 and D4S2364; multiplex II: D10S1248, D14S1434 and D22S1045; multiplex III: D12S391, D16S3253 and D20S161; multiplex IV: D3S4529, D8S1115 and D18S853; multiplex V: D6S1017, D11S4463 and D17S1301; multiplex VI: D5S2500, D9S1122 and D21S1437). Allele frequencies and forensic parameters were calculated to evaluate the suitability and robustness of these non-CODIS miniSTR systems. No significant deviation from Hardy-Weinberg equilibrium expectations were observed, except for D4S2364, D5S2500 and D20S161 loci. A multidimensional scaling plot based on allele frequencies of the six miniSTR loci (D1S1677, D2S441, D4S2364, D10S1248, D14S1434 and D22S1045) showed that Koreans appeared to have most genetic affinity with Chinese and Japanese than to other Eurasian populations compared here. The combined probability of match calculated from the 18 miniSTR loci was 2.902 × 10(-17), indicating a high degree of polymorphism. Thus, the 18 miniSTR loci can be suitable for recovering useful information for analyzing degraded forensic casework samples and for adding supplementary genetic information for a variety of analyses involving closely related individuals where there is a need for additional genetic information. Copyright © 2013 Elsevier Ltd and Faculty of Forensic and Legal Medicine. All rights reserved.

Evaluation of reliability on STR typing at leukemic patients used for forensic purposes.

PubMed

Filoglu, G; Bulbul, O; Rayimoglu, G; Yediay, F E; Zorlu, T; Ongoren, S; Altuncul, H

2014-06-01

Over the past decades, main advances in the field of molecular biology, coupled with benefits in genomic technologies, have led to detailed molecular investigations in the genetic diversity generated by researchers. Short tandem repeat (STR) loci are polymorphic loci found throughout all eukaryotic genome. DNA profiling identification, parental testing and kinship analysis by analysis of STR loci have been widely used in forensic sciences since 1993. Malignant tissues may sometimes be the source of biological material for forensic analysis, including identification of individuals or paternity testing. There are a number of studies on microsatellite instability in different types of tumors by comparing the STR profiles of malignant and healthy tissues on the same individuals. Defects in DNA repair pathways (non-repair or mis-repair) and metabolism lead to an accumulation of microsatellite alterations in genomic DNA of various cancer types that result genomic instabilities on forensic analyses. Common forms of genomic instability are loss of heterozygosity (LOH) and microsatellite instability (MSI). In this study, the applicability of autosomal STR markers, which are routinely used in forensic analysis, were investigated in order to detect genotypes in blood samples collected from leukemic patients to estimate the reliability of the results when malignant tissues are used as a source of forensic individual identification. Specimens were collected from 90 acute and 10 chronic leukemia volunteers with oral swabs as well as their paired peripheral blood samples from the Oncology Centre of the Department of Hematology at Istanbul University, during the years 2010-2011. Specimens were tested and compared with 16 somatic STR loci (CSFIPO, THO1, TPOX, vWA, D2S1338, D3S1358, D5S818, D7S820, D8S1179, D13S317, D16S539, D18S51, D19S433, D21S11 and FGA) widely used in forensic identification and kinship. Only two STR instabilities were encountered among 100 specimens. An MSI in the FGA loci and a LOH in the D2S1338 loci were determined in two individuals separately. Our results demonstrate that the use of the biological samples from leukemia patients in forensic identification and kinship testing is questionable, especially if known microsatellite instability is available. Genetic instabilities may alter the STR polymorphism, leading to potential errors on forensic identification of individuals. Therefore, typing of autosomal STRs from leukemia patients should be performed with both healthy and malignant tissue samples of individual as references.

[Forensic toxicology, a growing scientific discipline].

PubMed

Augsburger, Marc; Staub, Christian

2008-07-02

Forensic toxicology has to bring evidence of substances that could have been involved directly or indirectly in the cause of death or that could influence the behaviour of somebody. The increase of the consumption of illegal and legal drugs in modern societies during last decades gave a boost to forensic toxicology. Moreover, improvement with analytical technology gave tools with high degrees of sensitivity and specificity for the screening and quantification of a large amount of substances in various biological specimens, even with very low concentration resulting of a single dose of medication.

Characterization and microbial analysis of first recorded observation of Conicera similis Haliday (Diptera: Phoridae) in forensic decomposition study in Romania.

PubMed

Iancu, Lavinia; Junkins, Emily N; Purcarea, Cristina

2018-05-03

The identification of necrophagous insect diversity and dynamics has forensic significance for postmortem interval estimation specific to burial. Few studies regarding the necrophagous entomofauna from buried remains have been performed to date. In contrast to the exposed carcasses, the accessibility of soil to insects is limited due to burial depth and is dependent on soil type. This study highlights the colonization behavior of Conicera similis (Haliday 1833) (Diptera: Phoridae) during carcass decomposition, a previously unobserved taxon in Romania. Adult and larvae specimens were collected from rat (Rattus norvegicus) carcasses buried at 40 cm depth in an urban park environment in June 2016 during active decomposition and their presence and activity period was correlated with the environmental parameters variation. Bacterial diversity from C. similis female adult and larvae specimens was determined via 16S rRNA gene Illumina sequencing to further characterize these commonly encountered and forensically important necrophagous insects. This report signals the easternmost geographical location in Europe (Bucharest, Romania) of C. similis to date. Copyright © 2018 Elsevier Ltd and Faculty of Forensic and Legal Medicine. All rights reserved.

Interinstitutional review of slides for forensic pathology: types of inconsistencies.

PubMed

Ersoy, Gokhan; Akyildiz, Elif Ulker; Korkmaz, Gulay; Albek, Emre

2010-09-01

Because of the specific structure of forensic medicine in Turkey, reexamination of histopathologic specimens is a frequent practice. The aim of the present study is the assessment of microscopic diagnostic consistency in forensic pathology between different laboratories. Reports of the Council of Forensic Medicine between 2001 and 2004 were examined, and 150 cases with second pathologic examination were found. Results of histopathologic reports from peripheral laboratories were compared with those made by the Council pathologists with regard to diagnostic consistency. Consistency was assessed in 3 groups and 1 subgroup. Group 1, consistent and minor inconsistency; includes a major consistency subgroup. Group 2, major inconsistency, is the second diagnosis which is lethal; group 3, major inconsistency, is the first diagnosis which is lethal. The lung was found to be the organ with the highest frequency of diagnostic major inconsistency (group 2 and 3) and major consistency. Bronchopneumonia was the most common diagnosis. The brain had the highest frequency of intercenter diagnostic overall consistency (90.2%, group 1). Myocardial infarction was the diagnosis most frequently rejected on reevaluation (group 3). In conclusion, forensic pathology requires different experience than surgical ones. In cases of discrepancy between the anamnesis of the lethal event and pathologic findings, reevaluation of specimen is mandatory to avoid any diagnostic errors. Quality assurance systems with all include internal and external control mechanisms will improve the diagnostic reliability.

A 17-month time course study of human RNA and DNA degradation in body fluids under dry and humid environmental conditions.

PubMed

Sirker, Miriam; Schneider, Peter M; Gomes, Iva

2016-11-01

Blood, saliva, and semen are some of the forensically most relevant biological stains commonly found at crime scenes, which can often be of small size or challenging due to advanced decay. In this context, it is of great importance to possess reliable knowledge about the effects of degradation under different environmental conditions and to use appropriate methods for retrieving maximal information from limited sample amount. In the last decade, RNA analysis has been demonstrated to be a reliable approach identifying the cell or tissue type of an evidentiary body fluid trace. Hence, messenger RNA (mRNA) profiling is going to be implemented into forensic casework to supplement the routinely performed short tandem repeat (STR) analysis, and therefore, the ability to co-isolate RNA and DNA from the same sample is a prerequisite. The objective of this work was to monitor and compare the degradation process of both nucleic acids for human blood, saliva, and semen stains at three different concentrations, exposed to dry and humid conditions during a 17-month time period. This study also addressed the question whether there are relevant differences in the efficiency of automated, magnetic bead-based single DNA or RNA extraction methods compared to a manually performed co-extraction method using silica columns. Our data show that mRNA, especially from blood and semen, can be recovered over the entire time period surveyed without compromising the success of DNA profiling; mRNA analysis indicates to be a robust and reliable technique to identify the biological source of aged stain material. The co-extraction method appears to provide mRNA and DNA of sufficient quantity and quality for all different forensic investigation procedures. Humidity and accompanied mold formation are detrimental to both nucleic acids.

Filipino DNA variation at 12 X-chromosome short tandem repeat markers.

PubMed

Salvador, Jazelyn M; Apaga, Dame Loveliness T; Delfin, Frederick C; Calacal, Gayvelline C; Dennis, Sheila Estacio; De Ungria, Maria Corazon A

2018-06-08

Demands for solving complex kinship scenarios where only distant relatives are available for testing have risen in the past years. In these instances, other genetic markers such as X-chromosome short tandem repeat (X-STR) markers are employed to supplement autosomal and Y-chromosomal STR DNA typing. However, prior to use, the degree of STR polymorphism in the population requires evaluation through generation of an allele or haplotype frequency population database. This population database is also used for statistical evaluation of DNA typing results. Here, we report X-STR data from 143 unrelated Filipino male individuals who were genotyped via conventional polymerase chain reaction-capillary electrophoresis (PCR-CE) using the 12 X-STR loci included in the Investigator ® Argus X-12 kit (Qiagen) and via massively parallel sequencing (MPS) of seven X-STR loci included in the ForenSeq ™ DNA Signature Prep kit of the MiSeq ® FGx ™ Forensic Genomics System (Illumina). Allele calls between PCR-CE and MPS systems were consistent (100% concordance) across seven overlapping X-STRs. Allele and haplotype frequencies and other parameters of forensic interest were calculated based on length (PCR-CE, 12 X-STRs) and sequence (MPS, seven X-STRs) variations observed in the population. Results of our study indicate that the 12 X-STRs in the PCR-CE system are highly informative for the Filipino population. MPS of seven X-STR loci identified 73 X-STR alleles compared with 55 X-STR alleles that were identified solely by length via PCR-CE. Of the 73 sequence-based alleles observed, six alleles have not been reported in the literature. The population data presented here may serve as a reference Philippine frequency database of X-STRs for forensic casework applications. Copyright © 2018 Elsevier B.V. All rights reserved.

Forensic approach to an archaeological casework of "vampire" skeletal remains in Venice: odontological and anthropological prospectus.

PubMed

Nuzzolese, Emilio; Borrini, Matteo

2010-11-01

During the years 2006-2007, the Archeological Superintendent of Veneto (Italy) promoted a research project on mass graves located on Nuovo Lazzaretto in Venice, where the corpses of plague deaths were buried during the 16th and 17th centuries. The burials were of different stages and are believed to be the remains of plague victims from the numerous outbreaks of pestilence, which occurred between the 15th and 17th centuries. Among the fragmented and commingled human bones, an unusual burial was found. The body was laid supine, with the top half of the thorax intact, arms parallel to the rachis axis, the articulations were anatomically unaltered. Both the skull morphology and the dimensions of the caput omeris suggest the body was a woman. A brick of moderate size was found inside the oral cavity, keeping the mandible wide open. The data collected by the anthropologist were used to generate a taphonomic profile, which precluded the positioning of the brick being accidental. Likewise, the probability of the brick having come from the surrounding burial sediment was rejected, as the only other inclusions found were bone fragments from previous burials in the same area. The data collected by the odontologist were employed for age estimation and radiological dental assessment. The forensic profile was based conceptually on the "circumstances of death" and concluded that the positioning of the brick was intentional, and attributed to a symbolic burial ritual. This ritual confirms the intimate belief held at those times, between the plague and the mythological character of the vampire. © 2010 American Academy of Forensic Sciences.

Analysis of 12 X-STR loci in the population of south Croatia.

PubMed

Mršić, Gordan; Ozretić, Petar; Crnjac, Josip; Merkaš, Siniša; Račić, Ivana; Rožić, Sara; Sukser, Viktorija; Popović, Maja; Korolija, Marina

2017-02-01

The aim of the study was to assess forensic pertinence of 12 short tandem repeats (STRs) on X-chromosome in south Croatia population. Investigator ® Argus X-12 kit was used to co-amplify 12 STR loci belonging to four linkage groups (LGs) on X-chromosome in 99 male and 98 female DNA samples of unrelated donors. PCR products were analyzed by capillary electrophoresis. Population genetic and forensic parameters were calculated by the Arlequin and POPTREE2 software, and an on-line tool available at ChrX-STR.org. Hardy-Weinberg equilibrium was confirmed for all X-STR markers in female samples. Biallelic patterns at DXS10079 locus were detected in four male samples. Polymorphism information content for the most (DXS10135) and the least (DXS8378) informative markers was 0.9212 and 0.6347, respectively. In both male and female samples, combined power of discrimination exceeded 0.999999999. As confirmed by linkage disequilibrium test, significant association of marker pair DXS10074-DXS10079 (P = 0.0004) within LG2 and marker pair DXS10101-DXS10103 (P = 0.0003) within LG3 was found only in male samples. Number of observed haplotypes in our sample pool amounted 3.01, 7.53, 5 and 3.25% of the number of possible haplotypes for LG1, LG2, LG3 and LG4, respectively. According to haplotype diversity value of 0.9981, LG1 was the most informative. In comparison of south Croatia with 26 world populations, pair-wise [Formula: see text] values increase in parallel with geographical distance. Overall statistical assessment confirmed suitability of Investigator ® Argus X-12 kit for forensic casework in both identification and familial testing in the population of south Croatia.

An approach to shortening the timeframe between the emergence of new compounds on the drugs market and the availability of reference standards: The microscale syntheses of nitrazolam and clonazolam for use as reference materials, utilizing polymer-supported reagents.

PubMed

Dowling, Geraldine; Kavanagh, Pierce V; Eckhardt, Hans-Georg; Twamley, Brendan; Hessman, Gary; McLaughlin, Gavin; O'Brien, John; Brandt, Simon D

2018-03-15

Nitrazolam and clonazolam are 2 designer benzodiazepines available from Internet retailers. There is growing evidence suggesting that such compounds have the potential to cause severe adverse events. Information about tolerability in humans is scarce but typically, low doses can be difficult to administer for users when handling bulk material. Variability of the active ingredient in tablet formulations can also be of a concern. Customs, toxicology and forensic laboratories are increasingly encountering designer benzodiazepines, both in tablet and powdered form. The unavailability of reference standards can impact on the ability to identify these compounds. Therefore, the need arises for exploring in-house approaches to the preparation of new psychoactive substances (NPS) that can be carried out in a timely manner. The present study was triggered when samples of clonazolam were received in powdered and tablet form at a time when reference material for this drug was commercially unavailable. Therefore, microscale syntheses of clonazolam and its deschloro analog nitrazolam were developed utilizing polymer-supported reagents starting from 2-amino-2'-chloro-5-nitrobenzophenone (clonazolam) and 2-amino-5-nitrobenzophenone (nitrazolam). The final reaction step forming the 1,2,4-triazole ring moiety was performed within a gas chromatography-mass spectrometry (GC-MS) injector. A comparison with a preparative scale synthesis of both benzodiazepine derivatives showed that microscale synthesis might be an attractive option for a forensic laboratory in terms of time and cost savings when compared with traditional methods of synthesis and when qualitative identifications are needed to direct forensic casework. The reaction by-product profiles for both the micro and the preparative scale syntheses are also presented. Copyright © 2018 John Wiley & Sons, Ltd.

Identifying the substance abuse treatment needs of caregivers involved with child welfare.

PubMed

Chuang, Emmeline; Wells, Rebecca; Bellettiere, John; Cross, Theodore P

2013-07-01

Parental substance use significantly increases risk of child maltreatment, but is often under-identified by child protective services. This study examined how agency use of standardized substance use assessments and child welfare investigative caseworker education, experience, and caseload affected caseworkers' identification of parental substance abuse treatment needs. Data are from a national probability sample of permanent, primary caregivers involved with child protective services whose children initially remained at home and whose confidential responses on two validated instruments indicated harmful substance use or dependence. Investigative caseworkers reported use of a formal assessment in over two thirds of cases in which substance use was accurately identified. However, weighted logistic regression indicated that agency provision of standardized assessment instruments was not associated with caseworker identification of caregiver needs. Caseworkers were also less likely to identify substance abuse when their caseloads were high and when caregivers were fathers. Implications for agency practice are discussed. Copyright © 2013 Elsevier Inc. All rights reserved.

Child welfare caseworkers as service brokers for youth in foster care: findings from project focus.

PubMed

Dorsey, Shannon; Kerns, Suzanne E U; Trupin, Eric W; Conover, Kate L; Berliner, Lucy

2012-02-01

Youth in the foster care system have substantially higher rates of mental health needs compared to the general population, yet they rarely receive targeted, evidence-based practices (EBPs). Increasingly emerging in the literature on mental health services is the importance of "brokers" or "gateway providers" of services. For youth in foster care, child welfare caseworkers often play this role. This study examines caseworker-level outcomes of Project Focus, a caseworker training and consultation model designed to improve emotional and behavioral outcomes for youth in foster care through increased linkages with EBPs. Project Focus was tested through a small, randomized trial involving four child welfare offices. Caseworkers in the Project Focus intervention group demonstrated an increased awareness of EBPs and a trend toward increased ability to identify appropriate EBP referrals for particular mental health problems but did not have significantly different rates of actual referral to EBPs. Dose of consultation was associated with general awareness of EBPs. Implications for practice and outcomes for youth are discussed.

An investigation of normal urine with a creatinine concentration under the cutoff of 20 mg/dL for specimen validity testing in a toxicology laboratory.

PubMed

Holden, Brad; Guice, Erica A

2014-05-01

In clinical and forensic toxicology laboratories, one commonly used method for urine specimen validity testing is creatinine concentration. In this study, workplace guidelines are examined to determine their relevance to forensic and clinical toxicology samples. Specifically, it investigates the occurrence of urine creatinine concentrations under 20 mg/dL and notes potential issues with factors influencing creatinine concentration by utilizing a simple, novel method consisting of cation-paring high-pressure liquid chromatography in tandem with ultraviolet detection to determine the creatinine concentration in 3019 donors. Of the 4227 sample population in this study, 209 (4.94%) were below the cutoff value of 20 mg/dL for dilute urine. Because there are many factors that can influence the urinary creatinine concentration, samples that have creatinine under the 20 mg/dL cutoff do not always implicate sample adulteration. © 2014 American Academy of Forensic Sciences.

Elemental analysis of soils using laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) and laser-induced breakdown spectroscopy (LIBS) with multivariate discrimination: tape mounting as an alternative to pellets for small forensic transfer specimens.

PubMed

Jantzi, Sarah C; Almirall, José R

2014-01-01

Elemental analysis of soil is a useful application of both laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) and laser-induced breakdown spectroscopy (LIBS) in geological, agricultural, environmental, archeological, planetary, and forensic sciences. In forensic science, the question to be answered is often whether soil specimens found on objects (e.g., shoes, tires, or tools) originated from the crime scene or other location of interest. Elemental analysis of the soil from the object and the locations of interest results in a characteristic elemental profile of each specimen, consisting of the amount of each element present. Because multiple elements are measured, multivariate statistics can be used to compare the elemental profiles in order to determine whether the specimen from the object is similar to one of the locations of interest. Previous work involved milling and pressing 0.5 g of soil into pellets before analysis using LA-ICP-MS and LIBS. However, forensic examiners prefer techniques that require smaller samples, are less time consuming, and are less destructive, allowing for future analysis by other techniques. An alternative sample introduction method was developed to meet these needs while still providing quantitative results suitable for multivariate comparisons. The tape-mounting method involved deposition of a thin layer of soil onto double-sided adhesive tape. A comparison of tape-mounting and pellet method performance is reported for both LA-ICP-MS and LIBS. Calibration standards and reference materials, prepared using the tape method, were analyzed by LA-ICP-MS and LIBS. As with the pellet method, linear calibration curves were achieved with the tape method, as well as good precision and low bias. Soil specimens from Miami-Dade County were prepared by both the pellet and tape methods and analyzed by LA-ICP-MS and LIBS. Principal components analysis and linear discriminant analysis were applied to the multivariate data. Results from both the tape method and the pellet method were nearly identical, with clear groupings and correct classification rates of >94%.

Human genomic DNA quantitation system, H-Quant: development and validation for use in forensic casework.

PubMed

Shewale, Jaiprakash G; Schneida, Elaine; Wilson, Jonathan; Walker, Jerilyn A; Batzer, Mark A; Sinha, Sudhir K

2007-03-01

The human DNA quantification (H-Quant) system, developed for use in human identification, enables quantitation of human genomic DNA in biological samples. The assay is based on real-time amplification of AluYb8 insertions in hominoid primates. The relatively high copy number of subfamily-specific Alu repeats in the human genome enables quantification of very small amounts of human DNA. The oligonucleotide primers present in H-Quant are specific for human DNA and closely related great apes. During the real-time PCR, the SYBR Green I dye binds to the DNA that is synthesized by the human-specific AluYb8 oligonucleotide primers. The fluorescence of the bound SYBR Green I dye is measured at the end of each PCR cycle. The cycle at which the fluorescence crosses the chosen threshold correlates to the quantity of amplifiable DNA in that sample. The minimal sensitivity of the H-Quant system is 7.6 pg/microL of human DNA. The amplicon generated in the H-Quant assay is 216 bp, which is within the same range of the common amplifiable short tandem repeat (STR) amplicons. This size amplicon enables quantitation of amplifiable DNA as opposed to a quantitation of degraded or nonamplifiable DNA of smaller sizes. Development and validation studies were performed on the 7500 real-time PCR system following the Quality Assurance Standards for Forensic DNA Testing Laboratories.

Characterisation of gunshot residue from three ammunition types using suppressed anion exchange chromatography.

PubMed

Gilchrist, Elizabeth; Jongekrijg, Fleur; Harvey, Laura; Smith, Norman; Barron, Leon

2012-09-10

Gunshot residue (GSR) is commonly analysed in forensic casework using either scanning electron microscopy with energy-dispersive X-ray spectroscopy (SEM-EDX) or gas chromatography-mass spectrometry (GC-MS). Relatively little work has been reported on the post-discharge GSR content of non-metallic inorganic or low molecular weight organic anions to distinguish between different ammunition types. The development of an analytical method using suppressed micro-bore anion exchange chromatography (IC) is presented for the analysis of GSR. A hydroxide gradient was optimised for the separation of 19 forensically relevant organic and inorganic anions in <23min and sensitivities of the order of 0.12-3.52ng of anion detected for all species were achieved. Along with an optimised extraction procedure, this method was applied to the analysis of post-ignition residues from three selected ammunition types. By profiling and comparing the anionic content in each ammunition residue, the possibility to distinguish between each type using their anionic profiles and absolute weight is presented. The potential for interference is also discussed with respect to sample types which are typically problematic in the analysis of GSR using SEM-EDX and GC-MS. To the best of our knowledge this represents the first study on the analysis of inorganic anions in GSR using suppressed ion chromatography. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

Forensic DNA phenotyping in criminal investigations and criminal courts: assessing and mitigating the dilemmas inherent in the science.

PubMed

MacLean, Charles E; Lamparello, Adam

2014-01-01

Forensic DNA Phenotyping ("FDP"), estimating the externally visible characteristics ("EVCs") of the source of human DNA left at a crime scene, is evolving from science fiction toward science fact. FDP can already identify a source's gender with 100% accuracy, and likely hair color, iris color, adult height, and a number of other EVCs with accuracy rates approaching 70%. Patent applications have been filed for approaches to generating 3D likenesses of DNA sources based on the DNA alone. Nonetheless, criminal investigators, particularly in the United States, have been reticent to apply FDP in their casework. The reticence is likely related to a number of perceived and real dilemmas associated with FDP: is FDP racial profiling, should we test unknown and unseen physical conditions, does testing for behavioral characteristics impermissibly violate the source's privacy, ought testing be permitted for samples from known sources or DNA databases, and should FDP be limited to use in investigations only or is FDP appropriate for use in a criminal court. As this article explains, although those dilemmas are substantive, they are not insurmountable, and can be quite easily managed with appropriate regulation and protocols. As FDP continues to develop, there will be less need for criminal investigators to shy away from FDP. Cold cases, missing persons, and victims in crimes without other evidence will one day soon all be well served by FDP.

Fluorescence- and magnetic-activated cell sorting strategies to separate spermatozoa involving plural contributors from biological mixtures for human identification

PubMed Central

Xu, Yan; Xie, Jianhui; Chen, Ronghua; Cao, Yu; Ping, Yuan; Xu, Qingwen; Hu, Wei; Wu, Dan; Gu, Lihua; Zhou, Huaigu; Chen, Xin; Zhao, Ziqin; Zhong, Jiang; Li, Rui

2016-01-01

No effective method has been developed to distinguish sperm cells originating from different men in multi-suspect sexual assault cases. Here we combined MACS and FACS to isolate single donor sperm cells from forensic mixture samples including female vaginal epithelial cells and sperm cells from multiple contributors. Sperms from vaginal swab were isolated by MACS using FITC-conjugated A kinase anchor protein 3 (AKAP3) antibody; target individual sperm cells involving two or three donors were separated by FACS using FITC-labeled blood group A/B antigen antibody. This procedure was further tested in two mock multi-suspect sexual assault samples and one practical casework sample. Our results showed that complete single donor STR profiles could be successfully obtained from sperm/epithelial cell and sperm mixtures from two contributors. For unbalanced sperm/epithelial cells and sperm cells mixtures, sensitivity results revealed that target cells could be detected at as low as 1:32 and 1:8 mixed ratios, respectively. Although highly relies on cell number and blood types or secretor status of the individuals, this procedure would still be useful tools for forensic DNA analysis of multi-suspect sexual assault cases by the combined use of FACS and MACS based on sperm-specific AKAP3 antigen and human blood type antigen. PMID:27857155

Short tandem repeat analysis in Japanese population.

PubMed

Hashiyada, M

2000-01-01

Short tandem repeats (STRs), known as microsatellites, are one of the most informative genetic markers for characterizing biological materials. Because of the relatively small size of STR alleles (generally 100-350 nucleotides), amplification by polymerase chain reaction (PCR) is relatively easy, affording a high sensitivity of detection. In addition, STR loci can be amplified simultaneously in a multiplex PCR. Thus, substantial information can be obtained in a single analysis with the benefits of using less template DNA, reducing labor, and reducing the contamination. We investigated 14 STR loci in a Japanese population living in Sendai by three multiplex PCR kits, GenePrint PowerPlex 1.1 and 2.2. Fluorescent STR System (Promega, Madison, WI, USA) and AmpF/STR Profiler (Perkin-Elmer, Norwalk, CT, USA). Genomic DNA was extracted using sodium dodecyl sulfate (SDS) proteinase K or Chelex 100 treatment followed by the phenol/chloroform extraction. PCR was performed according to the manufacturer's protocols. Electrophoresis was carried out on an ABI 377 sequencer and the alleles were determined by GeneScan 2.0.2 software (Perkin-Elmer). In 14 STRs loci, statistical parameters indicated a relatively high rate, and no significant deviation from Hardy-Weinberg equilibrium was detected. We apply this STR system to paternity testing and forensic casework, e.g., personal identification in rape cases. This system is an effective tool in the forensic sciences to obtain information on individual identification.

A survey of extraction solvents in the forensic analysis of textile dyes.

PubMed

Groves, Ethan; Palenik, Christopher S; Palenik, Skip

2016-11-01

The characterization and identification of dyes in fibers can be used to provide investigative leads and strengthen associations between known and questioned items of evidence. The isolation of a dye from its matrix (e.g., a textile fiber) permits detailed characterization, comparison and, in some cases, identification using methods such as thin layer chromatography in conjunction with infrared and Raman spectroscopy. A survey of dye extraction publications reveals that pyridine:water (4:3) is among the most commonly cited extraction solvent across a range of fiber and dye chemistries. Here, the efficacy of this solvent system has been evaluated for the extraction of dyes from 172 commercially prevalent North American textile dyes. The evaluated population represents seven dye application classes, 18 chemical classes, and spans nine types of commercial textile fibers. The results of this survey indicate that ∼82% of the dyestuffs studied are extractable using this solvent system. The results presented here summarize the extraction efficacy by class and fiber type and illustrate that this solvent system is applicable to a wider variety of classes and fibers than previously indicated in the literature. While there is no universal solvent for fiber extraction, these results demonstrate that pyridine:water represents an excellent first step for extracting unknown dyes from questioned fibers in forensic casework. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Stable isotope ratio mass spectrometry and physical comparison for the forensic examination of grip-seal plastic bags.

PubMed

Taylor, Erica; Carter, James F; Hill, Jenny C; Morton, Carolyn; Daeid, Niamh Nic; Sleeman, Richard

2008-05-20

Plastic bags are frequently used to package drugs, explosives and other contraband. There exists, therefore, a requirement in forensic casework to compare bags found at different locations. This is currently achieved almost exclusively by the use of physical comparisons such as birefringence patterns. This paper discusses some of the advantages and shortcomings of this approach, and presents stable isotope ratio mass spectrometry (IRMS) as a supplementary tool for effecting comparisons of this nature. Carbon and hydrogen isotopic data are presented for sixteen grip-seal plastic bags from a wide range of sources, in order to demonstrate the range of values which is likely to be encountered. Both isotopic and physical comparison (specifically birefringence) techniques are then applied to the analysis of rolls of bags from different manufacturing lots from a leading manufacturer. Both approaches are able to associate bags from a common production batch. IRMS can be applied to small fragments which are not amenable to physical comparisons, and is able to discriminate bags which could be confused using birefringence patterns alone. Similarly, in certain cases birefringence patterns discriminate bags with similar isotopic compositions. The two approaches are therefore complementary. When more than one isotopically distinct region exists within a bag (e.g. the grip-seal is distinct from the body) the ability to discriminate and associate bags is greatly increased.

A global analysis of Y-chromosomal haplotype diversity for 23 STR loci.

PubMed

Purps, Josephine; Siegert, Sabine; Willuweit, Sascha; Nagy, Marion; Alves, Cíntia; Salazar, Renato; Angustia, Sheila M T; Santos, Lorna H; Anslinger, Katja; Bayer, Birgit; Ayub, Qasim; Wei, Wei; Xue, Yali; Tyler-Smith, Chris; Bafalluy, Miriam Baeta; Martínez-Jarreta, Begoña; Egyed, Balazs; Balitzki, Beate; Tschumi, Sibylle; Ballard, David; Court, Denise Syndercombe; Barrantes, Xinia; Bäßler, Gerhard; Wiest, Tina; Berger, Burkhard; Niederstätter, Harald; Parson, Walther; Davis, Carey; Budowle, Bruce; Burri, Helen; Borer, Urs; Koller, Christoph; Carvalho, Elizeu F; Domingues, Patricia M; Chamoun, Wafaa Takash; Coble, Michael D; Hill, Carolyn R; Corach, Daniel; Caputo, Mariela; D'Amato, Maria E; Davison, Sean; Decorte, Ronny; Larmuseau, Maarten H D; Ottoni, Claudio; Rickards, Olga; Lu, Di; Jiang, Chengtao; Dobosz, Tadeusz; Jonkisz, Anna; Frank, William E; Furac, Ivana; Gehrig, Christian; Castella, Vincent; Grskovic, Branka; Haas, Cordula; Wobst, Jana; Hadzic, Gavrilo; Drobnic, Katja; Honda, Katsuya; Hou, Yiping; Zhou, Di; Li, Yan; Hu, Shengping; Chen, Shenglan; Immel, Uta-Dorothee; Lessig, Rüdiger; Jakovski, Zlatko; Ilievska, Tanja; Klann, Anja E; García, Cristina Cano; de Knijff, Peter; Kraaijenbrink, Thirsa; Kondili, Aikaterini; Miniati, Penelope; Vouropoulou, Maria; Kovacevic, Lejla; Marjanovic, Damir; Lindner, Iris; Mansour, Issam; Al-Azem, Mouayyad; Andari, Ansar El; Marino, Miguel; Furfuro, Sandra; Locarno, Laura; Martín, Pablo; Luque, Gracia M; Alonso, Antonio; Miranda, Luís Souto; Moreira, Helena; Mizuno, Natsuko; Iwashima, Yasuki; Neto, Rodrigo S Moura; Nogueira, Tatiana L S; Silva, Rosane; Nastainczyk-Wulf, Marina; Edelmann, Jeanett; Kohl, Michael; Nie, Shengjie; Wang, Xianping; Cheng, Baowen; Núñez, Carolina; Pancorbo, Marian Martínez de; Olofsson, Jill K; Morling, Niels; Onofri, Valerio; Tagliabracci, Adriano; Pamjav, Horolma; Volgyi, Antonia; Barany, Gusztav; Pawlowski, Ryszard; Maciejewska, Agnieszka; Pelotti, Susi; Pepinski, Witold; Abreu-Glowacka, Monica; Phillips, Christopher; Cárdenas, Jorge; Rey-Gonzalez, Danel; Salas, Antonio; Brisighelli, Francesca; Capelli, Cristian; Toscanini, Ulises; Piccinini, Andrea; Piglionica, Marilidia; Baldassarra, Stefania L; Ploski, Rafal; Konarzewska, Magdalena; Jastrzebska, Emila; Robino, Carlo; Sajantila, Antti; Palo, Jukka U; Guevara, Evelyn; Salvador, Jazelyn; Ungria, Maria Corazon De; Rodriguez, Jae Joseph Russell; Schmidt, Ulrike; Schlauderer, Nicola; Saukko, Pekka; Schneider, Peter M; Sirker, Miriam; Shin, Kyoung-Jin; Oh, Yu Na; Skitsa, Iulia; Ampati, Alexandra; Smith, Tobi-Gail; Calvit, Lina Solis de; Stenzl, Vlastimil; Capal, Thomas; Tillmar, Andreas; Nilsson, Helena; Turrina, Stefania; De Leo, Domenico; Verzeletti, Andrea; Cortellini, Venusia; Wetton, Jon H; Gwynne, Gareth M; Jobling, Mark A; Whittle, Martin R; Sumita, Denilce R; Wolańska-Nowak, Paulina; Yong, Rita Y Y; Krawczak, Michael; Nothnagel, Michael; Roewer, Lutz

2014-09-01

In a worldwide collaborative effort, 19,630 Y-chromosomes were sampled from 129 different populations in 51 countries. These chromosomes were typed for 23 short-tandem repeat (STR) loci (DYS19, DYS389I, DYS389II, DYS390, DYS391, DYS392, DYS393, DYS385ab, DYS437, DYS438, DYS439, DYS448, DYS456, DYS458, DYS635, GATAH4, DYS481, DYS533, DYS549, DYS570, DYS576, and DYS643) and using the PowerPlex Y23 System (PPY23, Promega Corporation, Madison, WI). Locus-specific allelic spectra of these markers were determined and a consistently high level of allelic diversity was observed. A considerable number of null, duplicate and off-ladder alleles were revealed. Standard single-locus and haplotype-based parameters were calculated and compared between subsets of Y-STR markers established for forensic casework. The PPY23 marker set provides substantially stronger discriminatory power than other available kits but at the same time reveals the same general patterns of population structure as other marker sets. A strong correlation was observed between the number of Y-STRs included in a marker set and some of the forensic parameters under study. Interestingly a weak but consistent trend toward smaller genetic distances resulting from larger numbers of markers became apparent. Copyright © 2014 The Authors. Published by Elsevier Ireland Ltd.. All rights reserved.

Correlates of problem recognition and intentions to change among caregivers of abused and neglected children.

PubMed

Littell, Julia H; Girvin, Heather

2006-12-01

To identify individual, family, and caseworker characteristics associated with problem recognition (PR) and intentions to change (ITC) in a sample of caregivers who received in-home child welfare services following substantiated reports of child abuse or neglect. Caregivers were interviewed at 4 weeks, 16 weeks, and 1 year after referral for in-home services. In these interviews, the University of Rhode Island Change Assessment scale assessed PR and ITC in relation to caregiving practices. Additional data were obtained from administrative records and surveys of in-home services caseworkers. We used growth models to identify caregiver, family, and caseworker characteristics associated with initial levels of PR and ITC, and with changes in PR and ITC over time. Contrary to expectations, there were no overall increases in PR and ITC during the first 4 months of in-home services. PR and ITC scores fluctuated over time, in relation to some external events, case characteristics, and caseworker characteristics; however, we were able to account for small portions of the variance in PR and ITC. Controlling for social desirability bias and other variables in the analysis, negative life events, lack of network support, and the severity of caregiver depression were associated with greater PR; housing problems were associated with lower PR. Caregiver depression and age were associated with ITC. Caregivers whose children had been removed from their homes showed significant increases in ITC in the first few months of in-home services. The duration of caseworkers' child welfare experience predicted increases in their clients' PR in the first 4 months and more frequent contacts with an experienced caseworker predicted small, but significant increases in ITC over time. PR and ITC are associated with somewhat different case characteristics and may be affected by caseworkers' experience.

Analysis of Radiocarbon, Stable Isotopes and DNA in Teeth to Facilitate Identification of Unknown Decedents

PubMed Central

Alkass, Kanar; Saitoh, Hisako; Buchholz, Bruce A.; Bernard, Samuel; Holmlund, Gunilla; Senn, David R.; Spalding, Kirsty L.; Druid, Henrik

2013-01-01

The characterization of unidentified bodies or suspected human remains is a frequent and important task for forensic investigators. However, any identification method requires clues to the person’s identity to allow for comparisons with missing persons. If such clues are lacking, information about the year of birth, sex and geographic origin of the victim, is particularly helpful to aid in the identification casework and limit the search for possible matches. We present here results of stable isotope analysis of 13C and 18O, and bomb-pulse 14C analyses that can help in the casework. The 14C analysis of enamel provided information of the year of birth with an average absolute error of 1.8±1.3 years. We also found that analysis of enamel and root from the same tooth can be used to determine if the 14C values match the rising or falling part of the bomb-curve. Enamel laydown times can be used to estimate the date of birth of individuals, but here we show that this detour is unnecessary when using a large set of crude 14C data of tooth enamel as a reference. The levels of 13C in tooth enamel were higher in North America than in teeth from Europe and Asia, and Mexican teeth showed even higher levels than those from USA. DNA analysis was performed on 28 teeth, and provided individual-specific profiles in most cases and sex determination in all cases. In conclusion, these analyses can dramatically limit the number of possible matches and hence facilitate person identification work. PMID:23922751

Acid phosphatase test on Phadebas® sheets - An optimized method for presumptive saliva and semen detection.

PubMed

Herman, Yael; Feine, Ilan; Gafny, Ron

2018-04-30

The precise and efficient detection of semen and saliva in sexual assault case-work items is a critical step in the forensic pipeline. The outcome of this stage may have a profound impact on identifying perpetrators as well as on the investigation process and the final outcome in court. Semen detection is usually based on the activity of acid phosphatase (AP), an enzyme found in high concentration in the seminal plasma. Amylase, an enzyme catalyzing starch hydrolysis is found in high concentrations in saliva and therefore is a useful target for its detection. To screen case-work items, both presumptive tests require transfer of biological material from the item to paper in a moisturized environment. Since semen and saliva may appear in the same item, it is required in some cases to perform the tests one after the other. This may reduce the chances of identifying all stains on the item and obtaining a DNA profile. In the present study, we applied the AP biochemical test on a Phadebas ® sheet, a commercial starch containing paper used to detect saliva. This approach was found to be sensitive enough to detect diluted semen (1:50) after performing the Phadebas ® press test. In addition, it enabled detection of adjacent saliva and semen stains and stains containing a semen-saliva mixture. Finally, a DNA profile was successfully obtained from the Phadebas ® sheets after semen detection, a useful feature if the original item is lost or damaged. Taken together, this method provides a practical, reliable and convenient tool for screening sexual assault items of evidence. Copyright © 2018 Elsevier B.V. All rights reserved.

[Histopathological analysis of organs submitted by legal medicine experts in Baojii City: 358 forensic identification cases].

PubMed

Dong, Du-xuan; Shi, Ping-xia; Li, Yun-li; Tian, San-hu; Yang, Jia; Gao, Gang; Zheng, Yun; Jia, Le; Ju, Hong-ya; Sun, Lu-ying; Chen, Ni; Wang, Xiao-bao

2014-08-01

To analyze pathological characteristics of organs recovered during forensic autopsy submitted by legal medicine experts. From Baoji city, 358 cases of forensic autopsy specimens from a series of routine exams were collected. And histopathological diagnoses were reviewed. Majority of the 358 cases were young men. The major causes of death were trauma, sudden death and poisoning. The cause of death was determined with histology in 250 cases. No typical histological changes were noted in 101 cases. The tissue autolysis and decomposition were present in 7 cases. The major pathological diagnosis was cardiovascular disease, followed by diseases in respiratory, nervous, and digestive systems. Forensic autopsy with its professional characteristics, is different from regular autopsy. When diagnosing cause of death by histopathological examination, pathologists should collaborate with legal medicine experts to know the details of the cases, circumstances surrounding the death, and specific forensic pathological characteristics.

Analysis and estimation of service life of corrosion prevention materials using diffusion, resistivity and accelerated curing for new bridge structures : volume 1 : corrosion prevention materials (monitoring and forensic examination).

DOT National Transportation Integrated Search

2013-12-01

This investigation compiles the results describing the performance of: a) reinforced concrete specimens cast with : 0.37 water to cementitious (w/cm) and binary blends of high performance concrete; the specimens have been : exposed to seawater wet/dr...

Pericardial fluid is suitable as an alternative specimen for the measurement of β-hydroxybutyrate within 96 h after death.

PubMed

Mizutani, Tatsushi; Yoshimoto, Takashi; Ishii, Akira

2018-05-21

We examined postmortem β-hydroxybutyrate (BHB) levels in the body fluids obtained from 253 forensic autopsy cases whose causes of death were determined. Postmortem changes of BHB levels according to postmortem intervals (PMI) in various body fluids (plasma, urine, vitreous humor, and pericardial fluids) were investigated to determine appropriate alternative specimens as plasma samples. Our study has indicated the following points: 1) the BHB levels in plasma specimens from three sampling sites showed no significant differences, 2) postmortem changes of BHB levels in plasma and pericardial fluids could be negligible within 96 h PMI, while urine and vitreous humor BHB levels showed postmortem changes, and 3) pericardial fluid would thus be most suitable as an alternative to plasma in postmortem BHB level. We have also proposed that BHB levels could be applicable for the diagnosis of metabolic disorders in forensic autopsy. Copyright © 2018 Elsevier B.V. All rights reserved.

Cleaning Puparia for Forensic Analysis.

PubMed

Higley, Leon G; Brosius, Tierney R; Reinhard, Karl J; Carter, David

2016-09-01

We tested procedures for removing adipocere from insect samples to allow identification. An acceptable procedure was determined: (i) Samples were sorted in petri dishes with 75% alcohol to remove any larvae, adult insects, or other soft-bodied material. (ii) Samples of up to 24 puparia were placed in a vial with 15 mL of 95% acetone, capped, and vortexed for a total of 30-90 sec in 10- to 15-sec bursts. This step removed large masses of adipocere or soil from specimen. (iii) Specimens were removed from acetone and placed in a vial of 15 mL of 2% potassium hydroxide (KOH) and vortexed in 10- to 15-sec bursts until all puparia appeared clean (with our samples this required a total of 60-120 sec). (iv) Specimens were removed from the 2% KOH, placed in 75% ethanol, and examined microscopically. (v) Material was stored in 75% ethanol for identification and long-term preservation. © 2016 American Academy of Forensic Sciences.

Development and validation of InnoQuant™, a sensitive human DNA quantitation and degradation assessment method for forensic samples using high copy number mobile elements Alu and SVA.

PubMed

Pineda, Gina M; Montgomery, Anne H; Thompson, Robyn; Indest, Brooke; Carroll, Marion; Sinha, Sudhir K

2014-11-01

There is a constant need in forensic casework laboratories for an improved way to increase the first-pass success rate of forensic samples. The recent advances in mini STR analysis, SNP, and Alu marker systems have now made it possible to analyze highly compromised samples, yet few tools are available that can simultaneously provide an assessment of quantity, inhibition, and degradation in a sample prior to genotyping. Currently there are several different approaches used for fluorescence-based quantification assays which provide a measure of quantity and inhibition. However, a system which can also assess the extent of degradation in a forensic sample will be a useful tool for DNA analysts. Possessing this information prior to genotyping will allow an analyst to more informatively make downstream decisions for the successful typing of a forensic sample without unnecessarily consuming DNA extract. Real-time PCR provides a reliable method for determining the amount and quality of amplifiable DNA in a biological sample. Alu are Short Interspersed Elements (SINE), approximately 300bp insertions which are distributed throughout the human genome in large copy number. The use of an internal primer to amplify a segment of an Alu element allows for human specificity as well as high sensitivity when compared to a single copy target. The advantage of an Alu system is the presence of a large number (>1000) of fixed insertions in every human genome, which minimizes the individual specific variation possible when using a multi-copy target quantification system. This study utilizes two independent retrotransposon genomic targets to obtain quantification of an 80bp "short" DNA fragment and a 207bp "long" DNA fragment in a degraded DNA sample in the multiplex system InnoQuant™. The ratio of the two quantitation values provides a "Degradation Index", or a qualitative measure of a sample's extent of degradation. The Degradation Index was found to be predictive of the observed loss of STR markers and alleles as degradation increases. Use of a synthetic target as an internal positive control (IPC) provides an additional assessment for the presence of PCR inhibitors in the test sample. In conclusion, a DNA based qualitative/quantitative/inhibition assessment system that accurately predicts the status of a biological sample, will be a valuable tool for deciding which DNA test kit to utilize and how much target DNA to use, when processing compromised forensic samples for DNA testing. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

AQME: A forensic mitochondrial DNA analysis tool for next-generation sequencing data.

PubMed

Sturk-Andreaggi, Kimberly; Peck, Michelle A; Boysen, Cecilie; Dekker, Patrick; McMahon, Timothy P; Marshall, Charla K

2017-11-01

The feasibility of generating mitochondrial DNA (mtDNA) data has expanded considerably with the advent of next-generation sequencing (NGS), specifically in the generation of entire mtDNA genome (mitogenome) sequences. However, the analysis of these data has emerged as the greatest challenge to implementation in forensics. To address this need, a custom toolkit for use in the CLC Genomics Workbench (QIAGEN, Hilden, Germany) was developed through a collaborative effort between the Armed Forces Medical Examiner System - Armed Forces DNA Identification Laboratory (AFMES-AFDIL) and QIAGEN Bioinformatics. The AFDIL-QIAGEN mtDNA Expert, or AQME, generates an editable mtDNA profile that employs forensic conventions and includes the interpretation range required for mtDNA data reporting. AQME also integrates an mtDNA haplogroup estimate into the analysis workflow, which provides the analyst with phylogenetic nomenclature guidance and a profile quality check without the use of an external tool. Supplemental AQME outputs such as nucleotide-per-position metrics, configurable export files, and an audit trail are produced to assist the analyst during review. AQME is applied to standard CLC outputs and thus can be incorporated into any mtDNA bioinformatics pipeline within CLC regardless of sample type, library preparation or NGS platform. An evaluation of AQME was performed to demonstrate its functionality and reliability for the analysis of mitogenome NGS data. The study analyzed Illumina mitogenome data from 21 samples (including associated controls) of varying quality and sample preparations with the AQME toolkit. A total of 211 tool edits were automatically applied to 130 of the 698 total variants reported in an effort to adhere to forensic nomenclature. Although additional manual edits were required for three samples, supplemental tools such as mtDNA haplogroup estimation assisted in identifying and guiding these necessary modifications to the AQME-generated profile. Along with profile generation, AQME reported accurate haplogroups for 18 of the 19 samples analyzed. The single errant haplogroup assignment, although phylogenetically close, identified a bug that only affects partial mitogenome data. Future adjustments to AQME's haplogrouping tool will address this bug as well as enhance the overall scoring strategy to better refine and automate haplogroup assignments. As NGS enables broader use of the mtDNA locus in forensics, the availability of AQME and other forensic-focused mtDNA analysis tools will ease the transition and further support mitogenome analysis within routine casework. Toward this end, the AFMES-AFDIL has utilized the AQME toolbox in conjunction with the CLC Genomics Workbench to successfully validate and implement two NGS mitogenome methods. Copyright © 2017 Elsevier B.V. All rights reserved.

Supervision: A Sharing Process

ERIC Educational Resources Information Center

Schmidt, Dolores M.

1973-01-01

The social work supervisor's duties related to caseworkers are expediting, educating, and enabling. He uses leadership qualities to develop independence in the caseworker, which calls for a knowledgeable blend of authority and educational guidance. (Author/ST)

Species identification in forensic samples using the SPInDel approach: A GHEP-ISFG inter-laboratory collaborative exercise.

PubMed

Alves, Cíntia; Pereira, Rui; Prieto, Lourdes; Aler, Mercedes; Amaral, Cesar R L; Arévalo, Cristina; Berardi, Gabriela; Di Rocco, Florencia; Caputo, Mariela; Carmona, Cristian Hernandez; Catelli, Laura; Costa, Heloísa Afonso; Coufalova, Pavla; Furfuro, Sandra; García, Óscar; Gaviria, Anibal; Goios, Ana; Gómez, Juan José Builes; Hernández, Alexis; Hernández, Eva Del Carmen Betancor; Miranda, Luís; Parra, David; Pedrosa, Susana; Porto, Maria João Anjos; Rebelo, Maria de Lurdes; Spirito, Matteo; Torres, María Del Carmen Villalobos; Amorim, António; Pereira, Filipe

2017-05-01

DNA is a powerful tool available for forensic investigations requiring identification of species. However, it is necessary to develop and validate methods able to produce results in degraded and or low quality DNA samples with the high standards obligatory in forensic research. Here, we describe a voluntary collaborative exercise to test the recently developed Species Identification by Insertions/Deletions (SPInDel) method. The SPInDel kit allows the identification of species by the generation of numeric profiles combining the lengths of six mitochondrial ribosomal RNA (rRNA) gene regions amplified in a single reaction followed by capillary electrophoresis. The exercise was organized during 2014 by a Working Commission of the Spanish and Portuguese-Speaking Working Group of the International Society for Forensic Genetics (GHEP-ISFG), created in 2013. The 24 participating laboratories from 10 countries were asked to identify the species in 11 DNA samples from previous GHEP-ISFG proficiency tests using a SPInDel primer mix and control samples of the 10 target species. A computer software was also provided to the participants to assist the analyses of the results. All samples were correctly identified by 22 of the 24 laboratories, including samples with low amounts of DNA (hair shafts) and mixtures of saliva and blood. Correct species identifications were obtained in 238 of the 241 (98.8%) reported SPInDel profiles. Two laboratories were responsible for the three cases of misclassifications. The SPInDel was efficient in the identification of species in mixtures considering that only a single laboratory failed to detect a mixture in one sample. This result suggests that SPInDel is a valid method for mixture analyses without the need for DNA sequencing, with the advantage of identifying more than one species in a single reaction. The low frequency of wrong (5.0%) and missing (2.1%) alleles did not interfere with the correct species identification, which demonstrated the advantage of using a method based on the analysis of multiple loci. Overall, the SPInDel method was easily implemented by laboratories using different genotyping platforms, the interpretation of results was straightforward and the SPInDel software was used without any problems. The results of this collaborative exercise indicate that the SPInDel method can be applied successfully in forensic casework investigations. Copyright © 2017 Elsevier B.V. All rights reserved.

Can stable isotopes and radiocarbon dating provide a forensic solution for curbing illegal harvesting of threatened cycads?

PubMed

Retief, Kirsten; West, Adam G; Pfab, Michèle F

2014-11-01

Cycads in South Africa are facing an extinction crisis due to the illegal extraction of plants from the wild. Proving wild origin of suspect ex situ cycads to the satisfaction of a court of law is difficult, limiting law enforcement efforts. We investigated the feasibility of using multiple stable isotopes to identify specimens removed from the wild. Relocated and wild specimens from two species in the African genus Encephalartos (E. lebomboensis and E. arenarius) were sampled. (14) C analysis indicated that a ± 30-year chronology could be reliably obtained from the cycads. For E. arenarius, pre-relocation tissue was consistent with a wild origin, whereas tissue grown post-relocation was isotopically distinct from the wild for (87) Sr/(86) Sr and δ(15) N. For E. lebomboensis, δ(34) S, δ(18) O, and (87) Sr/(86) Sr were different between relocated and control plants, consistent with the >30 years since relocation. Our findings demonstrate the potential for a forensic isotope approach to identify illegal ex situ cycads. © 2014 American Academy of Forensic Sciences.

mtDNA sequence diversity of Hazara ethnic group from Pakistan.

PubMed

Rakha, Allah; Fatima; Peng, Min-Sheng; Adan, Atif; Bi, Rui; Yasmin, Memona; Yao, Yong-Gang

2017-09-01

The present study was undertaken to investigate mitochondrial DNA (mtDNA) control region sequences of Hazaras from Pakistan, so as to generate mtDNA reference database for forensic casework in Pakistan and to analyze phylogenetic relationship of this particular ethnic group with geographically proximal populations. Complete mtDNA control region (nt 16024-576) sequences were generated through Sanger Sequencing for 319 Hazara individuals from Quetta, Baluchistan. The population sample set showed a total of 189 distinct haplotypes, belonging mainly to West Eurasian (51.72%), East & Southeast Asian (29.78%) and South Asian (18.50%) haplogroups. Compared with other populations from Pakistan, the Hazara population had a relatively high haplotype diversity (0.9945) and a lower random match probability (0.0085). The dataset has been incorporated into EMPOP database under accession number EMP00680. The data herein comprises the largest, and likely most thoroughly examined, control region mtDNA dataset from Hazaras of Pakistan. Copyright © 2017 Elsevier B.V. All rights reserved.

Screening Test for Shed Skin Cells by Measuring the Ratio of Human DNA to Staphylococcus epidermidis DNA.

PubMed

Nakanishi, Hiroaki; Ohmori, Takeshi; Hara, Masaaki; Takahashi, Shirushi; Kurosu, Akira; Takada, Aya; Saito, Kazuyuki

2016-05-01

A novel screening method for shed skin cells by detecting Staphylococcus epidermidis (S. epidermidis), which is a resident bacterium on skin, was developed. Staphylococcus epidermidis was detected using real-time PCR. Staphylococcus epidermidis was detected in all 20 human skin surface samples. Although not present in blood and urine samples, S. epidermidis was detected in 6 of 20 saliva samples, and 5 of 18 semen samples. The ratio of human DNA to S. epidermidisDNA was significantly smaller in human skin surface samples than in saliva and semen samples in which S. epidermidis was detected. Therefore, although skin cells could not be identified by detecting only S. epidermidis, they could be distinguished by measuring the S. epidermidis to human DNA ratio. This method could be applied to casework touch samples, which suggests that it is useful for screening whether skin cells and human DNA are present on potential evidentiary touch samples. © 2016 American Academy of Forensic Sciences.

Analysis of extensively washed hair from cocaine users and drug chemists to establish new reporting criteria.

PubMed

Morris-Kukoski, Cynthia L; Montgomery, Madeline A; Hammer, Rena L

2014-01-01

Samples from a self-proclaimed cocaine (COC) user, from 19 drug users (postmortem) and from 27 drug chemists were extensively washed and analyzed for COC, benzoylecgonine, norcocaine (NC), cocaethylene (CE) and aryl hydroxycocaines by liquid chromatography-tandem mass spectrometry. Published wash criteria and cutoffs were applied to the results. Additionally, the data were used to formulate new reporting criteria and interpretation guidelines for forensic casework. Applying the wash and reporting criteria, hair that was externally contaminated with COC was distinguished from hair collected from individuals known to have consumed COC. In addition, CE, NC and hydroxycocaine metabolites were only present in COC users' hair and not in drug chemists' hair. When properly applied, the use of an extended wash, along with the reporting criteria defined here, will exclude false-positive results from environmental contact with COC. Published by Oxford University Press 2014. This work is written by (a) US Government employee(s) and is in the public domain in the US.

Genetic analysis of eight population groups living in Taiwan using a 13 X-chromosomal STR loci multiplex system.

PubMed

Hwa, Hsiao-Lin; Lee, James Chun-I; Chang, Yih-Yuan; Yin, Hsiang-Yi; Chen, Ya-Hui; Tseng, Li-Hui; Su, Yi-Ning; Ko, Tsang-Ming

2011-01-01

A 13 X-chromosomal short tandem repeat (STR) multiplex system (DXS6807, DXS8378, DSX9902, DXS7132, DXS9898, DXS6809, DXS6789, DXS7424, DXS101, GATA172D05, HPRTB, DXS8377, and DXS7423) was tested on 1,037 DNA samples from eight population groups currently living in Taiwan. Different distributions of the allelic frequencies in different populations were presented. DXS8377 and DXS101 were the two most polymorphic loci in these eight populations, whereas DXS7423 was the least informative marker in most of the populations studied. The genetic distances between the populations and the constructed phylogenetic tree revealed a long genetic distance between Asian and Caucasian populations as well as isolation of the Tao population. The phylogenetic tree grouped populations into clusters compatible with their ethnogeographic relationships. This 13 X-chromosomal short tandem repeat multiplex system offers a considerable number of polymorphic patterns in different populations. This system can be useful in forensic identification casework and ethnogeographic research.

Whole genome amplification and real-time PCR in forensic casework

PubMed Central

Giardina, Emiliano; Pietrangeli, Ilenia; Martone, Claudia; Zampatti, Stefania; Marsala, Patrizio; Gabriele, Luciano; Ricci, Omero; Solla, Gianluca; Asili, Paola; Arcudi, Giovanni; Spinella, Aldo; Novelli, Giuseppe

2009-01-01

Background WGA (Whole Genome Amplification) in forensic genetics can eliminate the technical limitations arising from low amounts of genomic DNA (gDNA). However, it has not been used to date because any amplification bias generated may complicate the interpretation of results. Our aim in this paper was to assess the applicability of MDA to forensic SNP genotyping by performing a comparative analysis of genomic and amplified DNA samples. A 26-SNPs TaqMan panel specifically designed for low copy number (LCN) and/or severely degraded genomic DNA was typed on 100 genomic as well as amplified DNA samples. Results Aliquots containing 1, 0.1 and 0.01 ng each of 100 DNA samples were typed for a 26-SNPs panel. Similar aliquots of the same DNA samples underwent multiple displacement amplification (MDA) before being typed for the same panel. Genomic DNA samples showed 0% PCR failure rate for all three dilutions, whilst the PCR failure rate of the amplified DNA samples was 0% for the 1 ng and 0.1 ng dilutions and 0.077% for the 0.01 ng dilution. The genotyping results of both the amplified and genomic DNA samples were also compared with reference genotypes of the same samples obtained by direct sequencing. The genomic DNA samples showed genotype concordance rates of 100% for all three dilutions while the concordance rates of the amplified DNA samples were 100% for the 1 ng and 0.1 ng dilutions and 99.923% for the 0.01 ng dilution. Moreover, ten artificially-degraded DNA samples, which gave no results when analyzed by current forensic methods, were also amplified by MDA and genotyped with 100% concordance. Conclusion We investigated the suitability of MDA material for forensic SNP typing. Comparative analysis of amplified and genomic DNA samples showed that a large number of SNPs could be accurately typed starting from just 0.01 ng of template. We found that the MDA genotyping call and accuracy rates were only slightly lower than those for genomic DNA. Indeed, when 10 pg of input DNA was used in MDA, we obtained 99.923% concordance, indicating a genotyping error rate of 1/1299 (7.7 × 10-4). This is quite similar to the genotyping error rate of STRs used in current forensic analysis. Such efficiency and accuracy of SNP typing of amplified DNA suggest that MDA can also generate large amounts of genome-equivalent DNA from a minimal amount of input DNA. These results show for the first time that MDA material is suitable for SNP-based forensic protocols and in general when samples fail to give interpretable STR results. PMID:19366436

Analysis of fingerprint samples, testing various conditions, for forensic DNA identification.

PubMed

Ostojic, Lana; Wurmbach, Elisa

2017-01-01

Fingerprints can be of tremendous value for forensic biology, since they can be collected from a wide variety of evident types, such as handles of weapons, tools collected in criminal cases, and objects with no apparent staining. DNA obtained from fingerprints varies greatly in quality and quantity, which ultimately affects the quality of the resulting STR profiles. Additional difficulties can arise when fingerprint samples show mixed STR profiles due to the handling of multiple persons. After applying a tested protocol for sample collection (swabbing with 5% Triton X-100), DNA extraction (using an enzyme that works at elevated temperatures), and PCR amplification (AmpFlSTR® Identifiler® using 31cycles) extensive analysis was performed to better understand the challenges inherent to fingerprint samples, with the ultimate goal of developing valuable profiles (≥50% complete). The impact of time on deposited fingerprints was investigated, revealing that while the quality of profiles deteriorated, full STR profiles could still be obtained from samples after 40days of storage at room temperature. By comparing the STR profiles from fingerprints of the dominant versus the non-dominant hand, we found a slightly better quality from the non-dominant hand, which was not always significant. Substrates seem to have greater effects on fingerprints. Tests on glass, plastic, paper and metal (US Quarter dollar, made of Cu and Ni), common substrates in offices and homes, showed best results for glass, followed by plastic and paper, while almost no profiles were obtained from a Quarter dollar. Important for forensic casework, we also assessed three-person mixtures of touched fingerprint samples. Unlike routinely used approaches for sampling evidence, the surface of an object (bottle) was sectioned into six equal parts and separate samples were taken from each section. The samples were processed separately for DNA extraction and STR amplification. The results included a few single source profiles and distinguishable two person mixtures. On average, this approach led to two profiles ≥50% complete per touched object. Some STR profiles were obtained more than once thereby increasing the confidence. Copyright © 2016 The Chartered Society of Forensic Sciences. Published by Elsevier Ireland Ltd. All rights reserved.

Identifying the Substance Abuse Treatment Needs of Caregivers Involved with Child Welfare

PubMed Central

Wells, Rebecca; Bellettiere, John; Cross, Theodore P.

2013-01-01

Parental substance use significantly increases risk of child maltreatment, but is often under-identified by child protective services. This study examined how agency use of standardized substance use assessments and child welfare investigative caseworker education, experience, and caseload affected caseworkers’ identification of parental substance abuse treatment needs. Data are from a national probability sample of permanent, primary caregivers involved with child protective services whose children initially remained at home and whose confidential responses on two validated instruments indicated harmful substance use or dependence. Investigative caseworkers reported use of a formal assessment in over two thirds of cases in which substance use was accurately identified. However, weighted logistic regression indicated that agency provision of standardized assessment instruments was not associated with caseworker identification of caregiver needs. Caseworkers were also less likely to identify substance abuse when their caseloads were high and when caregivers were fathers. Implications for agency practice are discussed. PMID:23453481

Forensic entomology investigations from Doctor Marcel Leclercq (1924-2008): a review of cases from 1969 to 2005.

PubMed

Dekeirsschieter, J; Frederickx, C; Verheggen, F J; Boxho, P; Haubruge, E

2013-09-01

Dr. Marcel Leclercq was a pioneer in the field of forensic entomology. He has provided his knowledge of insect biology to many forensic cases, and most of them have found the way to publication. Most of the articles he has written were focused on individual cases, and despite the abundance of entomoforensic investigations he conducted, no synthesis has been published. This article summarizes 36 yr of forensic entomological investigations in temperate Europe, mainly in Belgium. Dr. Leclercq's work includes 132 entomological cases involving 141 human corpses found in various death scenes. Under certain conditions, insect specimens found at death scene can provide information on when (postmortem interval estimation), where and how a person died. More or less 100 insect species associated with a dead body have been identified by Dr. Leclercq.

Organizational climate, services, and outcomes in child welfare systems.

PubMed

Glisson, Charles; Green, Philip

2011-08-01

This study examines the association of organizational climate, casework services, and youth outcomes in child welfare systems. Building on preliminary findings linking organizational climate to youth outcomes over a 3-year follow-up period, the current study extends the follow-up period to 7 years and tests main, moderating and mediating effects of organizational climate and casework services on outcomes. The study applies hierarchical linear models (HLMs) analyses to all 5 waves of the National Survey of Child and Adolescent Well-being (NSCAW) with a US nationwide sample of 1,678 maltreated youth aged 4-16 years and 1,696 caseworkers from 88 child welfare systems. Organizational climate is assessed on 2 dimensions, Engagement and Stress, with scales from the well established measure, Organizational Social Context (OSC); youth outcomes are measured as problems in psychosocial functioning with the Child Behavior Checklist (CBCL); and casework services are assessed with original scales developed for the study and completed by the maltreated youths' primary caregivers and caseworkers. Maltreated youth served by child welfare systems with more engaged organizational climates have significantly better outcomes. Moreover, the quantity and quality of casework services neither mediate nor interact with the effects of organizational climate on youth outcomes. Organizational climate is associated with youth outcomes in child welfare systems, but a better understanding is needed of the mechanisms that link organizational climate to outcomes. In addition, there is a need for evidence-based organizational interventions that can improve the organizational climates and effectiveness of child welfare systems. Copyright © 2011 Elsevier Ltd. All rights reserved.

The 'triple contrast' method in experimental wound ballistics and backspatter analysis.

PubMed

Schyma, Christian; Lux, Constantin; Madea, Burkhard; Courts, Cornelius

2015-09-01

In practical forensic casework, backspatter recovered from shooters' hands can be an indicator of self-inflicted gunshot wounds to the head. In such cases, backspatter retrieved from inside the barrel indicates that the weapon found at the death scene was involved in causing the injury to the head. However, systematic research on the aspects conditioning presence, amount and specific patterns of backspatter is lacking so far. Herein, a new concept of backspatter investigation is presented, comprising staining technique, weapon and target medium: the 'triple contrast method' was developed, tested and is introduced for experimental backspatter analysis. First, mixtures of various proportions of acrylic paint for optical detection, barium sulphate for radiocontrast imaging in computed tomography and fresh human blood for PCR-based DNA profiling were generated (triple mixture) and tested for DNA quantification and short tandem repeat (STR) typing success. All tested mixtures yielded sufficient DNA that produced full STR profiles suitable for forensic identification. Then, for backspatter analysis, sealed foil bags containing the triple mixture were attached to plastic bottles filled with 10% ballistic gelatine and covered by a 2-3-mm layer of silicone. To simulate backspatter, close contact shots were fired at these models. Endoscopy of the barrel inside revealed coloured backspatter containing typable DNA and radiographic imaging showed a contrasted bullet path in the gelatine. Cross sections of the gelatine core exhibited cracks and fissures stained by the acrylic paint facilitating wound ballistic analysis.

Examination of forensic entomology evidence using computed tomography scanning: case studies and refinement of techniques for estimating maggot mass volumes in bodies.

PubMed

Johnson, Aidan; Archer, Melanie; Leigh-Shaw, Lyndie; Pais, Mike; O'Donnell, Chris; Wallman, James

2012-09-01

A new technique has recently been developed for estimating the volume of maggot masses on deceased persons using post-mortem CT scans. This allows volume to be measured non-invasively and factored into maggot mass temperature calculations for both casework and research. Examination of admission scans also allows exploration of entomological evidence in anatomical areas not usually exposed by autopsy (e.g. nasal cavities and facial sinuses), and before autopsy disrupts the maggot distribution on a body. This paper expands on work already completed by providing the x-ray attenuation coefficient by way of Hounsfield unit (HU) values for various maggot species, maggot masses and human tissue adjacent to masses. Specifically, this study looked at the HU values for four forensically important blowfly larvae: Lucilia cuprina, L. sericata, Calliphora stygia and C. vicina. The Calliphora species had significantly lower HU values than the Lucilia species. This might be explained by histological analysis, which revealed a non-significant trend, suggesting that Calliphora maggots have a higher fat content than the Lucilia maggots. It is apparent that the variation in the x-ray attenuation coefficient usually precludes its use as a tool for delineating the maggot mass from human tissue and that morphology is the dominant method for delineating a mass. This paper also includes three case studies, which reveal different applications for interpreting entomological evidence using post-mortem CT scans.

Chemical discrimination of lubricant marketing types using direct analysis in real time time-of-flight mass spectrometry.

PubMed

Maric, Mark; Harvey, Lauren; Tomcsak, Maren; Solano, Angelique; Bridge, Candice

2017-06-30

In comparison to other violent crimes, sexual assaults suffer from very low prosecution and conviction rates especially in the absence of DNA evidence. As a result, the forensic community needs to utilize other forms of trace contact evidence, like lubricant evidence, in order to provide a link between the victim and the assailant. In this study, 90 personal bottled and condom lubricants from the three main marketing types, silicone-based, water-based and condoms, were characterized by direct analysis in real time time of flight mass spectrometry (DART-TOFMS). The instrumental data was analyzed by multivariate statistics including hierarchal cluster analysis, principal component analysis, and linear discriminant analysis. By interpreting the mass spectral data with multivariate statistics, 12 discrete groupings were identified, indicating inherent chemical diversity not only between but within the three main marketing groups. A number of unique chemical markers, both major and minor, were identified, other than the three main chemical components (i.e. PEG, PDMS and nonoxynol-9) currently used for lubricant classification. The data was validated by a stratified 20% withheld cross-validation which demonstrated that there was minimal overlap between the groupings. Based on the groupings identified and unique features of each group, a highly discriminating statistical model was then developed that aims to provide the foundation for the development of a forensic lubricant database that may eventually be applied to casework. Copyright © 2017 John Wiley & Sons, Ltd. Copyright © 2017 John Wiley & Sons, Ltd.

The first report of Telomerina flavipes (Meigen, 1830) (Diptera, Sphaeroceridae) in a forensic case, with redescription of its pupa.

PubMed

Arnaldos, María-Isabel; Ubero-Pascal, Nicolás; García, Rafael; Carles-Tolrá, Miguel; Presa, Juan-José; García, María-Dolores

2014-09-01

This paper presents a forensic investigation that took place in the city of Murcia (SE Spain) and shows how the entomological specimens collected at the scene were extremely helpful for estimating the minimum post-mortem interval (PMImin). The occurrence of Telomerina flavipes (Meigen, 1830) (Diptera: Sphaeroceridae) is reported here for the first time in a forensic case. Additionally, the importance of other entomological evidence in this case is discussed. The first known images of the puparium are provided, as well as its redescription and that of the cephalopharyngeal skeleton recovered from the puparium. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

The effects of the ARC organizational intervention on caseworker turnover, climate, and culture in children's service systems.

PubMed

Glisson, Charles; Dukes, Denzel; Green, Philip

2006-08-01

This study examines the effects of the Availability, Responsiveness, and Continuity (ARC) organizational intervention strategy on caseworker turnover, climate, and culture in a child welfare and juvenile justice system. Using a pre-post, randomized blocks, true experimental design, 10 urban and 16 rural case management teams were randomly assigned to either the ARC organizational intervention condition or to a control condition. The culture and climate of each case management team were assessed at baseline and again after the one-year organizational intervention was completed. In addition, caseworker turnover was assessed by identifying caseworkers on the sampled teams who quit their jobs during the year. Hierarchical Linear Models (HLM) analyses indicate that the ARC organizational intervention reduced the probability of caseworker turnover by two-thirds and improved organizational climate by reducing role conflict, role overload, emotional exhaustion, and depersonalization in both urban and rural case management teams. Organizational intervention strategies can be used to reduce staff turnover and improve organizational climates in urban and rural child welfare and juvenile justice systems. This is important because child welfare and juvenile justice systems in the U.S.A. are plagued by high turnover rates, and there is evidence that high staff turnover and poor organizational climates negatively affect service quality and outcomes in these systems.

Recent applications of mass spectrometry in forensic toxicology

NASA Astrophysics Data System (ADS)

Foltz, Rodger L.

1992-09-01

This review encompasses applications of mass spectrometry reported during the years 1989, 1990 and 1991 for the analysis of cannabinoids, cocaine, opiates, amphetamines, lysergic acid diethylamide (LSD), and their metabolites in physiological specimens.

Effectiveness of saliva and fingerprints as alternative specimens to urine and blood in forensic drug testing.

PubMed

Kuwayama, Kenji; Miyaguchi, Hajime; Yamamuro, Tadashi; Tsujikawa, Kenji; Kanamori, Tatsuyuki; Iwata, Yuko T; Inoue, Hiroyuki

2016-07-01

In forensic drug testing, it is important to immediately take biological specimens from suspects and victims to prove their drug intake. We evaluated the effectiveness of saliva and fingerprints as alternative specimens to urine and blood in terms of ease of sampling, drug detection sensitivity, and drug detection periods for each specimen type. After four commercially available pharmaceutical products were administered to healthy subjects, each in a single dose, their urine, blood, saliva, and fingerprints were taken at predetermined sampling times over approximately four weeks. Fourteen analytes (the administered drugs and their main metabolites) were extracted from each specimen using simple pretreatments, such as dilution and deproteinization, and were analyzed using liquid chromatography/mass spectrometry (LC/MS). Most of the analytes were detected in saliva and fingerprints, as well as in urine and blood. The time-courses of drug concentrations were similar between urine and fingerprints, and between blood and saliva. Compared to the other compounds, the acidic compounds, for example ibuprofen, acetylsalicylic acid, were more difficult to detect in all specimens. Acetaminophen, dihydrocodeine, and methylephedrine were detected in fingerprints at later sampling times than in urine. However, a relationship between the drug structures and their detection periods in each specimen was not found. Saliva and fingerprints could be easily sampled on site without using special techniques or facilities. In addition, fingerprints could be immediately analyzed after simple and rapid treatment. In cases where it would be difficult to immediately obtain urine and blood, saliva and fingerprints could be effective alternative specimens for drug testing. Copyright © 2015 John Wiley & Sons, Ltd. Copyright © 2015 John Wiley & Sons, Ltd.

Forensically important calliphoridae (diptera) associated with pig carrion in rural north-central Florida

USGS Publications Warehouse

Gruner, Susan V.; Slone, D.H.; Capinera, J.L.

2007-01-01

A study to determine the relative abundance and seasonality of forensically important blow flies (Diptera: Calliphoridae) in rural north-central Florida was conducted using pig carcasses (Sus scrofa L.) as models for human bodies. Seven species of Calliphoridae were collected: Lucilia coeruleiviridis (=Phoenicia) (Macquart), Cochliomyia macellaria (F.), Chrysomya rufifaces (Macquart), Phormia regina (Meigen), Chrysomya megacephala (F.), and a few specimens of Calliphora livida Hall, and Calliphora vicina Robineau-Desvoidy. Species composition in aerial collections of adult flies, preserved larval collections, and samples of larvae reared to the adult stage were all highly correlated. Relative abundance of the species found was significantly different, with L. coeruleiviridis the most abundant species year-round. The relative abundance of the collected species varied significantly by day of decomposition and by season, with significant interactions between season and day, season and species, and day and species. L. coeruleiviridis, C. macellaria, C. rufifaces, and P. regina were found during the entire year, two C. vicina specimens and 11 C. livida specimens were collected from December to March, whereas C. megacephala was collected only from June through September. ?? 2007 Entomological Society of America.

A guideline for the validation of likelihood ratio methods used for forensic evidence evaluation.

PubMed

Meuwly, Didier; Ramos, Daniel; Haraksim, Rudolf

2017-07-01

This Guideline proposes a protocol for the validation of forensic evaluation methods at the source level, using the Likelihood Ratio framework as defined within the Bayes' inference model. In the context of the inference of identity of source, the Likelihood Ratio is used to evaluate the strength of the evidence for a trace specimen, e.g. a fingermark, and a reference specimen, e.g. a fingerprint, to originate from common or different sources. Some theoretical aspects of probabilities necessary for this Guideline were discussed prior to its elaboration, which started after a workshop of forensic researchers and practitioners involved in this topic. In the workshop, the following questions were addressed: "which aspects of a forensic evaluation scenario need to be validated?", "what is the role of the LR as part of a decision process?" and "how to deal with uncertainty in the LR calculation?". The questions: "what to validate?" focuses on the validation methods and criteria and "how to validate?" deals with the implementation of the validation protocol. Answers to these questions were deemed necessary with several objectives. First, concepts typical for validation standards [1], such as performance characteristics, performance metrics and validation criteria, will be adapted or applied by analogy to the LR framework. Second, a validation strategy will be defined. Third, validation methods will be described. Finally, a validation protocol and an example of validation report will be proposed, which can be applied to the forensic fields developing and validating LR methods for the evaluation of the strength of evidence at source level under the following propositions. Copyright © 2016. Published by Elsevier B.V.

Forensic SNP Genotyping with SNaPshot: Development of a Novel In-house SBE Multiplex SNP Assay.

PubMed

Zar, Mian Sahib; Shahid, Ahmad Ali; Shahzad, Muhammad Saqib; Shin, Kyoung-Jin; Lee, Hwan Young; Lee, Sang-Seob; Israr, Muhammad; Wiegand, Peter; Kulstein, Galina

2018-04-10

This study introduces a newly developed in-house SNaPshot single-base extension (SBE) multiplex assay for forensic single nucleotide polymorphism (SNP) genotyping of fresh and degraded samples. The assay was validated with fresh blood samples from four different populations. In addition, altogether 24 samples from skeletal remains were analyzed with the multiplex. Full SNP profiles could be obtained from 14 specimens, while ten remains showed partial SNP profiles. Minor allele frequencies (MAF) of bone samples and different populations were compared and used for association of skeletal remains with a certain population. The results reveal that the SNPs of the bone samples are genetically close to the Pathan population. The findings show that the new multiplex system can be utilized for SNP genotyping of degraded and forensic relevant skeletal material, enabling to provide additional investigative leads in criminal cases. © 2018 American Academy of Forensic Sciences.

An investigation into the factors that influence toolmark identifications on ammunition discharged from semi-automatic pistols recovered from car fires.

PubMed

Collender, Mark A; Doherty, Kevin A J; Stanton, Kenneth T

2017-01-01

Following a shooting incident where a vehicle is used to convey the culprits to and from the scene, both the getaway car and the firearm are often deliberately burned in an attempt to destroy any forensic evidence which may be subsequently recovered. Here we investigate the factors that influence the ability to make toolmark identifications on ammunition discharged from pistols recovered from such car fires. This work was carried out by conducting a number of controlled furnace tests in conjunction with real car fire tests in which three 9mm semi-automatic pistols were burned. Comparisons between pre-burn and post burn test fired ammunition discharged from these pistols were then performed to establish if identifications were still possible. The surfaces of the furnace heated samples and car fire samples were examined following heating/burning to establish what factors had influenced their surface morphology. The primary influence on the surfaces of the furnace heated and car fire samples was the formation of oxide layers. The car fire samples were altered to a greater extent than the furnace heated samples. Identifications were still possible between pre- and post-burn discharged cartridge cases, but this was not the case for the discharged bullets. It is suggested that the reason for this is a difference between the types of firearms discharge-generated toolmarks impressed onto the base of cartridge cases compared to those striated along the surfaces of bullets. It was also found that the temperatures recorded in the front foot wells were considerably less than those recorded on top of the rear seats during the car fires. These factors should be assessed by forensic firearms examiners when performing casework involving pistols recovered from car fires. Copyright © 2016 The Chartered Society of Forensic Sciences. Published by Elsevier Ireland Ltd. All rights reserved.

Production of high-fidelity electropherograms results in improved and consistent DNA interpretation: Standardizing the forensic validation process.

PubMed

Peters, Kelsey C; Swaminathan, Harish; Sheehan, Jennifer; Duffy, Ken R; Lun, Desmond S; Grgicak, Catherine M

2017-11-01

Samples containing low-copy numbers of DNA are routinely encountered in casework. The signal acquired from these sample types can be difficult to interpret as they do not always contain all of the genotypic information from each contributor, where the loss of genetic information is associated with sampling and detection effects. The present work focuses on developing a validation scheme to aid in mitigating the effects of the latter. We establish a scheme designed to simultaneously improve signal resolution and detection rates without costly large-scale experimental validation studies by applying a combined simulation and experimental based approach. Specifically, we parameterize an in silico DNA pipeline with experimental data acquired from the laboratory and use this to evaluate multifarious scenarios in a cost-effective manner. Metrics such as signal 1copy -to-noise resolution, false positive and false negative signal detection rates are used to select tenable laboratory parameters that result in high-fidelity signal in the single-copy regime. We demonstrate that the metrics acquired from simulation are consistent with experimental data obtained from two capillary electrophoresis platforms and various injection parameters. Once good resolution is obtained, analytical thresholds can be determined using detection error tradeoff analysis, if necessary. Decreasing the limit of detection of the forensic process to one copy of DNA is a powerful mechanism by which to increase the information content on minor components of a mixture, which is particularly important for probabilistic system inference. If the forensic pipeline is engineered such that high-fidelity electropherogram signal is obtained, then the likelihood ratio (LR) of a true contributor increases and the probability that the LR of a randomly chosen person is greater than one decreases. This is, potentially, the first step towards standardization of the analytical pipeline across operational laboratories. Copyright © 2017 Elsevier B.V. All rights reserved.

Measuring Parent Engagement in Foster Care

ERIC Educational Resources Information Center

Alpert, Lily T.; Britner, Preston A.

2009-01-01

Today, child welfare agencies widely endorse a family-centered approach to foster care casework. This approach centers on a collaborative parent-caseworker relationship as a mechanism for maintaining parents' engagement in services and presumes that continued engagement will propel parents toward reunification. However, despite the importance of…

Growing Financial Assets for Foster Youths: Expanded Child Welfare Responsibilities, Policy Conflict, and Caseworker Role Tension.

PubMed

Peters, Clark M; Sherraden, Margaret; Kuchinski, Ann Marie

2016-10-01

The study reported in this article explores the role child welfare workers play in elevating the financial capability (FC) of foster youths transitioning to adulthood. It draws on an examination of Opportunity Passport, a component of the Jim Casey Youth Opportunities Initiative, which operates across the United States. The authors held in-depth, structured interviews with eight staff and 38 current and former foster youths age 18 years and older in four sites across three states. Findings indicate that (a) program participants require professional financial assistance that is beyond the role of the traditional child welfare caseworker; (b) caseworkers who address FC in young adults face uncertainty in their roles; and (c) broader policies relevant to young adults transitioning to adulthood exhibit tension, if not conflict, regarding enhancing FC. The authors highlight the importance of expanding the role of caseworkers to incorporate elements of FC in serving the needs of foster youths.

Under What Conditions Does Caseworker-Caregiver Racial/Ethnic Similarity Matter for Housing Service Provision? An Application of Representative Bureaucracy Theory.

PubMed

McBeath, Bowen; Chuang, Emmeline; Bunger, Alicia; Blakeslee, Jennifer

2014-03-01

In this article, we examine child welfare caseworkers' housing-related service strategies when they serve culturally similar versus culturally dissimilar clients. Testing hypotheses drawn from representative bureaucracy theory and using data from the second cohort of the National Survey of Child and Adolescent Well-Being, we find that when non-Caucasian caseworkers share the same racial/ethnic background as caregivers, caseworkers use more active strategies to connect caregivers to needed housing services. The relationship between racial/ethnic matching and frontline workers' repertoire of service strategies is most pronounced when the need for housing has been registered formally via referrals and case plans and thus legitimated institutionally. These results reinforce basic tenets of representative bureaucracy theory and provide evidence of the benefits of racial and ethnic diversity in the human service workforce. Our findings also highlight the need for research identifying institutional and frontline organizational factors that enhance the quality of service provision.

Role of metabolites in aviation forensic toxicology.

DOT National Transportation Integrated Search

1995-08-01

In aviation accident investigations, specimens from fatal aircraft victims are analyzed for drugs. Their presence indicates exposure to drugs and suggests possible associated medical conditions for which they might have been taken. As drugs are mostl...

Issues in Correctional Training and Casework. Correctional Monograph.

ERIC Educational Resources Information Center

Wolford, Bruce I., Ed.; Lawrenz, Pam, Ed.

The eight papers contained in this monograph were drawn from two national meetings on correctional training and casework. Titles and authors are: "The Challenge of Professionalism in Correctional Training" (Michael J. Gilbert); "A New Perspective in Correctional Training" (Jack Lewis); "Reasonable Expectations in Correctional Officer Training:…

Analysis of Novel Synthetic Opioids U-47700, U-50488 and Furanyl Fentanyl by LC-MS/MS in Postmortem Casework.

PubMed

Mohr, Amanda L A; Friscia, Melissa; Papsun, Donna; Kacinko, Sherri L; Buzby, David; Logan, Barry K

2016-11-01

Following series of synthetic cannabinoid and synthetic cathinone derivatives, the illicit drug market has begun to see increased incidence of synthetic opioids including fentanyl and its derivatives, and other chemically unrelated opioid agonists including AH-7921 and MT-45. Among the most frequently encountered compounds in postmortem casework have been furanyl fentanyl (N-(1-(2-phenylethyl)-4-piperidinyl)-N-phenylfuran-2-carboxamide, Fu-F) and U-47700 (trans-3,4-dichloro-N-(2-(dimethylamino)cyclohexyl)-N-methylbenzamide). Both drugs have been reported to be present in the heroin supply and to be gaining popularity among recreational opioid users, but were initially developed by pharmaceutical companies in the 1970s as candidates for development as potential analgesic therapeutic agents. A method was developed and validated for the analysis of U-47700, U-50488 and furanyl fentanyl in blood specimens. A total of 20 postmortem cases, initially believed to be heroin or other opioid-related drug overdoses, were submitted for quantitative analysis. The analytical range for U-47770 and U-50488 was 1-500 and 1-100 ng/mL for furanyl fentanyl. The limit of detection was 0.5 ng/mL for all compounds. Within the scope of the method, U-47700 was the only confirmed drug in 11 of the cases, 5 cases were confirmed for both U-47700 and furanyl fentanyl, and 3 cases were confirmed only for furanyl fentanyl. The mean and median blood concentrations for U-47700 were 253 ng/mL (±150) and 247 ng/mL, respectively, range 17-490 ng/mL. The mean and median blood concentrations for furanyl fentanyl were 26 ng/mL (±28) and 12.9 ng/mL, respectively, range 2.5-76 ng/mL. Given the widespread geographical distribution and increase in prevalence in postmortem casework, toxicology testing should be expanded to include testing for "designer opioids" in cases with histories consistent with opioid overdose but with no traditional opioids present or insufficient quantities to account for death. © The Author 2016. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Scanning Electron Microscopy and X-Ray Microanalysis for Chemical and Morphological Characterisation of the Inorganic Component of Gunshot Residue: Selected Problems

PubMed Central

Brożek-Mucha, Zuzanna

2014-01-01

Chosen aspects of examinations of inorganic gunshot particles by means of scanning electron microscopy and energy dispersive X-ray spectrometry technique are presented. The research methodology of particles was worked out, which included a precise and repeatable procedure of the automatic detection and identification of particles as well as the representation of the obtained analytical data in the form of the frequencies of occurrence of particles of certain chemical or morphological class within the whole population of particles revealed in a specimen. On this basis, there were established relationships between the chemical and morphological properties of populations of particles and factors, such as the type of ammunition, the distance from the gun muzzle to the target, the type of a substrate the particles sediment on, and the time between shooting and collecting the specimens. Each of these aspects of examinations of particles revealed a great potential of being utilised in casework, while establishing various circumstances of shooting incidents leads to the reconstruction of the course of the studied incident. PMID:25025050

Forensically Relevant Blow Flies in Lebanon Survey and Identification Using Molecular Markers (Diptera: Calliphoridae).

PubMed

Shayya, Salman; Debruyne, Régis; Nel, André; Azar, Dany

2018-05-12

Calliphoridae are among the first insects associated to decomposing animal remains. We have collected 1,841 specimens of three calliphorid genera: Calliphora, Lucilia, and Chrysomya, from different Lebanese localities as a first step in implementing a database of insects of forensic relevance for the country. Blow-flies are crucial for the estimation of the postmortem interval. DNA-based identification is a rapid and accurate method, often used for morphologically similar species, especially for immatures or incomplete specimens. In this study, we test the suitability of three genetic markers to identify adults and immature stages of calliphorids, viz., mitochondrial cytochrome c oxidase subunit I (COI) barcode, a region including partial sequences of mitochondrial Cyt-b-tRNAser-ND1, and second internal transcribed spacer (ITS2) region of nuclear ribosomal DNA. Forty Lebanese specimens of various developmental stages (egg, larva, wandering third instar, pupa, newly emerged adult, and mature adult) were identified among the three calliphorid genera: Calliphora, Lucilia, and Chrysomya, and compared with published sequences to confirm their specific assignation. Phylogenetic analyses showed the robustness of ITS2 and COI to identify calliphorids at species level. Nevertheless, ITS2 failed to discriminate Lucilia caesar (Linnaeus) (Diptera, Calliphoridae) from Lucilia illustris (Meigen) (Diptera, Calliphoridae), and COI had a similar issue with Lucilia sericata (Meigen) (Diptera, Calliphoridae) and Lucilia cuprina (Wiedemann) (Diptera, Calliphoridae). Thus, these two markers are complementary. This work contributes new nucleotide sequences for Lebanon. It is a first step in implementing a molecular database of forensic relevant insects for the country.

Are animal models predictive for human postmortem muscle protein degradation?

PubMed

Ehrenfellner, Bianca; Zissler, Angela; Steinbacher, Peter; Monticelli, Fabio C; Pittner, Stefan

2017-11-01

A most precise determination of the postmortem interval (PMI) is a crucial aspect in forensic casework. Although there are diverse approaches available to date, the high heterogeneity of cases together with the respective postmortal changes often limit the validity and sufficiency of many methods. Recently, a novel approach for time since death estimation by the analysis of postmortal changes of muscle proteins was proposed. It is however necessary to improve the reliability and accuracy, especially by analysis of possible influencing factors on protein degradation. This is ideally investigated on standardized animal models that, however, require legitimization by a comparison of human and animal tissue, and in this specific case of protein degradation profiles. Only if protein degradation events occur in comparable fashion within different species, respective findings can sufficiently be transferred from the animal model to application in humans. Therefor samples from two frequently used animal models (mouse and pig), as well as forensic cases with representative protein profiles of highly differing PMIs were analyzed. Despite physical and physiological differences between species, western blot analysis revealed similar patterns in most of the investigated proteins. Even most degradation events occurred in comparable fashion. In some other aspects, however, human and animal profiles depicted distinct differences. The results of this experimental series clearly indicate the huge importance of comparative studies, whenever animal models are considered. Although animal models could be shown to reflect the basic principles of protein degradation processes in humans, we also gained insight in the difficulties and limitations of the applicability of the developed methodology in different mammalian species regarding protein specificity and methodic functionality.

An update on MALDI mass spectrometry based technology for the analysis of fingermarks - stepping into operational deployment.

PubMed

Francese, S; Bradshaw, R; Denison, N

2017-07-10

Since 2009, when Matrix Assisted Laser Desorption Ionisation Mass Spectrometry Imaging (MALDI MSI) was firstly reported for the molecular mapping of latent fingermarks, the range of information and operational capabilities have steadily increased. Pioneering work from our Fingermark Research Group exploited different modalities, including Profiling (MALDI MSP), tandem mass spectrometry (MS/MS) and Ion Mobility MS/MS; a number of methodologies were also developed to conquer a main challenge, namely profiling the suspect and their actions prior to or whilst committing the crime. Suspect profiling here is no longer based on behavioural science but complements this discipline and the investigations by detecting and visualising the molecular make-up of fingermarks onto the identifying ridges. This forensic opportunity provides the link between the biometric information (ridge detail) and the corpus delicti or intelligence on the circumstances of the crime. In 2013, a review was published covering the research work and developments of four years supported by the Home Office, UK, and the local regional Police with some insights (and comparison) into similar research being reported employing other mass spectrometric techniques. The present review is an extensive update on the MALDI MS based methods' achievements, limitations and work in progress in fingermark analysis; it also offers an outlook on further necessary research into this subject. The main highlights are the increased number of possible information retrievable around a suspect and the more extended compatibility of this technology. The latter has allowed MALDI MS based methods to integrate well with current forensic fingerprinting, leading to the investigation of real police casework.

Application of STR markers in wildlife forensic casework involving Australian black-cockatoos (Calyptorhynchus spp.).

PubMed

White, Nicole E; Dawson, Rick; Coghlan, Megan L; Tridico, Silvana R; Mawson, Peter R; Haile, James; Bunce, Michael

2012-09-01

Parrots and cockatoos are highly prized aviary birds and the demands for such species has fuelled their illegal trade and harvest from the wild. Here we report on three forensic case studies involving black-cockatoos (Calyptorhynchus spp.) endemic to Australia. These cases involve suspected poaching and illegal killing of endangered red- and white-tailed black-cockatoos. Through the prior development of 20 polymorphic microsatellite loci and population databases for white- and red-tailed black-cockatoos, the tools are available to conduct high-resolution paternity and individual identity testing. In one case, we matched a red-tailed black-cockatoo nestling to a tree hollow from which it was poached through the use of DNA from eggshell recovered from the nest. For the second case, we utilized our provenance population database (nest sites), and identified the kinship and geographic origin of a white-tailed black-cockatoo, which was illegally harvested from the wild. The third case determined the number individual white-tailed black-cockatoos allegedly shot at a fruit grower's orchard from body part remains. These genetic investigations highlight the significance and statistical confidence of DNA profiling and associated databases for endangered taxa, such as exotic birds. Our cockatoo population databases are the first of their kind in Australia, and demonstrate the efficacy of such approaches to identify such illegal activity. With a robust set of genetic markers and methodologies in place, we aim to broaden our population databases to include other cockatoo species of conservation concern. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

Individualization of pubic hair bacterial communities and the effects of storage time and temperature.

PubMed

Williams, Diana W; Gibson, Greg

2017-01-01

A potential application of microbial genetics in forensic science is detection of transfer of the pubic hair microbiome between individuals during sexual intercourse using high-throughput sequencing. In addition to the primary need to show whether the pubic hair microbiome is individualizing, one aspect that must be addressed before using the microbiome in criminal casework involves the impact of storage on the microbiome of samples recovered for forensic testing. To test the effects of short-term storage, pubic hair samples were collected from volunteers and stored at room temperature (∼20°C), refrigerated (4°C), and frozen (-20°C) for 1 week, 2 weeks, 4 weeks, and 6 weeks along with a baseline sample. Individual microbial profiles (R 2 =0.69) and gender (R 2 =0.17) were the greatest sources of variation between samples. Because of this variation, individual and gender could be predicted using Random Forests supervised classification in this sample set with an overall error rate of 2.7%± 5.8% and 1.7%±5.2%, respectively. There was no statistically significant difference attributable to time of sampling or temperature of storage within individuals. Further work on larger sample sets will quantify the temporal consistency of individual profiles and define whether it is plausible to detect transfer between sexual partners. For short-term storage (≤6 weeks), recovery of the microbiome was not affected significantly by either storage time or temperature, suggesting that investigators and crime laboratories can use existing evidence storage methods. Published by Elsevier Ireland Ltd.

Frequency of pubic hair transfer during sexual intercourse.

PubMed

Exline, D L; Smith, F P; Drexler, S G

1998-05-01

This study measured the frequency of pubic hair transfer between a limited number of consenting heterosexual partners. The results derive from controlled experiments with a number of human subjects rather than forensic casework. Standardized collection procedures were observed, situational variables were tracked. Participants (forensic laboratory employees and their spouses) were six Caucasian couples who collected their pubic hair combings immediately following intercourse. Subjects provided informed consent in accordance with the protocol for human subjects approved by the U.A.B. institutional review board. The experiment was replicated ten times for five couples, and five times for another couple (total n = 110). Transfer frequencies were calculated from instances where foreign (exogenous) hairs were observed. Results showed at least one exogenous pubic hair in 17.3% (19/110) of combings. Transfers to males (23.6%, or 13/55) were more prevalent than transfers to females (10.9%, or 6/55). Only once were transfers observed simultaneously between both male and female. A total of 28 exogenous pubic hairs were identified. Subjects reported intercourse duration of 2-25 min, intervening intervals of 1-240 h, pre-coital bathing intervals of 0.25-24 h, and predominantly missionary position (76%). No clear relationship among these other survey variables was observed. The prevalence of female-to-male pubic hair transfers suggests the importance of collecting pubic hair combings from the male suspects as well as from female victims, provided the time interval is not extreme. Even under these optimum collection conditions, pubic hair transfers were observed only 17.3% of the time.

Identifying Obstacles to Adoption in New York State's Out-of-Home Care System.

ERIC Educational Resources Information Center

Avery, Rosemary J.

1999-01-01

This study queried caseworkers for 77 New York children in out-of-home care still waiting for placement to determine obstacles to permanent adoption. Questionnaires sought demographics, placement efforts, and caseworker opinions. Findings indicated several obstacles, including the following: child's strong emotional ties to family (foster or…

Caseworker-Recipient Interaction: Welfare Office Differences, Economic Trajectories, and Child Outcomes

ERIC Educational Resources Information Center

Godfrey, Erin B.; Yoshikawa, Hirokazu

2012-01-01

Drawing on developmental and policy research, this study examined whether 3 dimensions of caseworker-recipient interaction in welfare offices functioned as critical ecological contexts for recipient families. The sample consisted of 1,098 families from 10 welfare offices in National Evaluation of Welfare to Work Strategies (NEWWS). In multilevel…

A Multiplex PCR assay to differentiate between dog and red fox.

PubMed

Weissenberger, M; Reichert, W; Mattern, R

2011-11-01

Foxes are frequently the cause of car accidents in Baden-Württemberg (BW, Germany). The domestic dog (Canis familiaris) is in close relation to the red fox (Vulpes vulpes) and the silver fox which is a coat colour variant of the red fox. As insurance claims that involve accidents with animals require authentication, we analyzed frequency distribution and allele sizes in two canine microsatellite loci in 26 dogs (different breeds) and 19 red foxes of the region of BW, Germany. Moreover, sequencing analysis was performed. Red foxes exhibited only 1 allele at each microsatellite locus, whereas in dog 7 alleles at the CPH4 locus and 6 alleles at the CPH12 locus were detected. Sequences of PCR products from the two species revealed several differences between dogs and foxes. We established a sequenced allelic ladder and give population data from dogs and red foxes from the region of BW, Germany. Using microsatellite polymorphisms is efficient in differentiating between dogs and foxes in forensic casework. Copyright © 2010 Elsevier Ireland Ltd. All rights reserved.

Identification of bodies from the scene of a mass disaster using DNA amplification of short tandem repeat (STR) loci.

PubMed

Clayton, T M; Whitaker, J P; Maguire, C N

1995-11-30

The accompanying paper in this issue describes work conducted during a collaborative effort to identify the victims of a mass disaster that occurred on the 19th of April 1993 near Waco, Texas. The DNA identification programme was also used partly as an exercise to further investigate the robustness and reliability of a recently developed STR quadruplex. The preceding paper provides details of the loci used and also deals with efforts to assess the applicability of STR profiling and its suitability for forensic investigations of this nature. In this paper, we present the results obtained from 61 Waco bodies. Using reference blood samples and family trees 26 positive identifications were made using a 'paternity style' analytical approach. Worked examples, representing a range of casework situations, are used to illustrate the kind of approach taken in interpretation of the data and highlight factors which affected its success. Additionally, we report on the successful application of a PCR-based gender test to 24 of the Waco bodies.

DNA profiles from clothing fibers using direct PCR.

PubMed

Blackie, Renée; Taylor, Duncan; Linacre, Adrian

2016-09-01

We report on the successful use of direct PCR amplification of single fibers from items of worn clothing. Items of clothing were worn throughout the course of a day, with the individual commencing regular activities. Single fibers were taken from the cuff of the clothing at regular intervals and amplified directly. The same areas were subjected to tape-lifting, and also amplified directly for comparison. The NGM™ kit that amplifies 15 STR loci plus amelogenin was used. A total of 35 single fiber samples were processed and analyzed from five items of clothing, with 81 % of samples returning a profile of 14 alleles or more. All tape-lift samples amplified directly produced DNA profiles of 15 alleles or more. The aim was to develop a simple, operational method that could be used routinely in forensic science casework and that has the potential to generate more complete profiles, which would not be detected using standard extraction methods on this type of sample. For ease of implementation, the process also adheres to standard methods with no increase in the cycle number.

Fantastic plastic? Experimental evaluation of polyurethane bone substitutes as proxies for human bone in trauma simulations.

PubMed

Smith, Martin J; James, Stephen; Pover, Tim; Ball, Nina; Barnetson, Victoria; Foster, Bethany; Guy, Carl; Rickman, John; Walton, Virginia

2015-09-01

Recent years have seen steady improvements in the recognition and interpretation of violence related injuries in human skeletal remains. Such work has at times benefited from the involvement of biological anthropologists in forensic casework and has often relied upon comparison of documented examples with trauma observed in skeletal remains. In cases where no such example exists investigators must turn to experimentation. The selection of experimental samples is problematic as animal proxies may be too dissimilar to humans and human cadavers may be undesirable for a raft of reasons. The current article examines a third alternative in the form of polyurethane plates and spheres marketed as viable proxies for human bone in ballistic experiments. Through subjecting these samples to a range of impacts from both modern and archaic missile weapons it was established that such material generally responds similarly to bone on a broad, macroscopic scale but when examined in closer detail exhibits a range of dissimilarities that call for caution in extrapolating such results to real bone. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Detection of the Spermicide Nonoxynol-9 Via GC-MS

NASA Astrophysics Data System (ADS)

Musah, Rabi A.; Vuong, Angela L.; Henck, Colin; Shepard, Jason R. E.

2012-05-01

The spermicide nonoxynol-9 is actually a complex mixture of dozens of closely related amphiphilic compounds, and the chemical properties of this assortment significantly hamper its characterization by GC-MS. The inability to perform routine GC-MS testing on nonoxynol-9 has limited its evidentiary value in forensic casework, which relies heavily on this technique for analysis. A disturbing trend in sexual assault is the use of condoms by assailants, to avoid leaving behind DNA evidence that can connect a perpetrator to a victim. This observation necessitates the development of alternative methods for the analysis of trace evidence that can show causal links between a victim and a suspect. Detection of lubricants associated with sexual assault is one such way to establish this connection. The development of GC-MS methods that permit facile detection of both nonoxynol-9 alone and nonoxynol-9 extracted from other complex matrices that have potential as trace evidence in sexual assault is reported. A detection limit of 2.14 μg of nonoxynol-9 is demonstrated, and a detailed mass spectral profile that elaborates on what is known of its structure is provided.

Low-template methods yield limited extra information for PowerPlex® Fusion 6C profiling.

PubMed

Duijs, Francisca; van de Merwe, Linda; Sijen, Titia; Benschop, Corina C G

2018-06-01

Advances in autosomal DNA profiling systems enable analyzing increased numbers of short tandem repeat (STR) loci in one reaction. Increasing the number of STR loci increases the amount of information that may be obtained from a (crime scene) sample. In this study, we examined whether even more allelic information can be obtained by applying low-template methods. To this aim, the performance of the PowerPlex® Fusion 6C STR typing system was assessed when increasing the number of PCR cycles or enhancing the capillary electrophoresis (CE) injection settings. Results show that applying these low-template methods yields limited extra information and comes at cost of more background noise. In addition, the gain in detection of alleles was much smaller when compared to the gain when applying low-template methods to the 15-loci AmpFLSTR® NGM™ system. Consequently, the PowerPlex® Fusion 6C STR typing system was implemented using standard settings only; low-template methods were not implemented for our routine forensic casework. Copyright © 2018 Elsevier B.V. All rights reserved.

An artificial neural network system to identify alleles in reference electropherograms.

PubMed

Taylor, Duncan; Harrison, Ash; Powers, David

2017-09-01

Electropherograms are produced in great numbers in forensic DNA laboratories as part of everyday criminal casework. Before the results of these electropherograms can be used they must be scrutinised by analysts to determine what the identified data tells them about the underlying DNA sequences and what is purely an artefact of the DNA profiling process. This process of interpreting the electropherograms can be time consuming and is prone to subjective differences between analysts. Recently it was demonstrated that artificial neural networks could be used to classify information within an electropherogram as allelic (i.e. representative of a DNA fragment present in the DNA extract) or as one of several different categories of artefactual fluorescence that arise as a result of generating an electropherogram. We extend that work here to demonstrate a series of algorithms and artificial neural networks that can be used to identify peaks on an electropherogram and classify them. We demonstrate the functioning of the system on several profiles and compare the results to a leading commercial DNA profile reading system. Copyright © 2017 Elsevier B.V. All rights reserved.

An Accelerated Analytical Process for the Development of STR Profiles for Casework Samples.

PubMed

Laurin, Nancy; Frégeau, Chantal J

2015-07-01

Significant efforts are being devoted to the development of methods enabling rapid generation of short tandem repeat (STR) profiles in order to reduce turnaround times for the delivery of human identification results from biological evidence. Some of the proposed solutions are still costly and low throughput. This study describes the optimization of an analytical process enabling the generation of complete STR profiles (single-source or mixed profiles) for human identification in approximately 5 h. This accelerated process uses currently available reagents and standard laboratory equipment. It includes a 30-min lysis step, a 27-min DNA extraction using the Promega Maxwell(®) 16 System, DNA quantification in <1 h using the Qiagen Investigator(®) Quantiplex HYres kit, fast amplification (<26 min) of the loci included in AmpFℓSTR(®) Identifiler(®), and analysis of the profiles on the 3500-series Genetic Analyzer. This combination of fast individual steps produces high-quality profiling results and offers a cost-effective alternative approach to rapid DNA analysis. © 2015 American Academy of Forensic Sciences.

Forensic botany: species identification of botanical trace evidence using a multigene barcoding approach.

PubMed

Ferri, Gianmarco; Alù, Milena; Corradini, Beatrice; Beduschi, Giovanni

2009-09-01

Forensic botany can provide significant supporting evidence during criminal investigations. However, it is still an underutilized field of investigation with its most common application limited to identifying specific as well as suspected illegal plants. The ubiquitous presence of plant species can be useful in forensics, but the absence of an accurate identification system remains the major obstacle to the present inability to routinely and correctly identify trace botanical evidence. Many plant materials cannot be identified and differentiated to the species level by traditional morphological characteristics when botanical specimens are degraded and lack physical features. By taking advantage of a universal barcode system, DNA sequencing, and other biomolecular techniques used routinely in forensic investigations, two chloroplast DNA regions were evaluated for their use as "barcoding" markers for plant identification in the field of forensics. We therefore investigated the forensic use of two non-coding plastid regions, psbA-trnH and trnL-trnF, to create a multimarker system for species identification that could be useful throughout the plant kingdom. The sequences from 63 plants belonging to our local flora were submitted and registered on the GenBank database. Sequence comparison to set up the level of identification (species, genus, or family) through Blast algorithms allowed us to assess the suitability of this method. The results confirmed the effectiveness of our botanic universal multimarker assay in forensic investigations.

Working with refugees--a manual for caseworkers and volunteers.

PubMed

Duncan, Geraldine; Shepherd, Madeleine; Symons, Jessica

2010-01-01

The Australian Government encourages the regional settlement of refugees and it is expected that 45% of refugees to Australia be regionally located. Wagga Wagga, an inland regional city in New South Wales (NSW), a destination for both primary and secondary migration, offers settlement for refugees under the Australian Integrated Humanitarian Settlement Strategy (IHSS) and the Settlement Grants Program. Refugees currently represent 1% of Wagga Wagga's 60 000 population. For people previously living in cities or crowded camps with a background of disruption, torture and trauma, relocation to rural areas of Australia is confronting, and they require dedication and effort from those supporting resettlement. Currently, caseworkers working for settlement agencies do not have formal training. Volunteers are offered induction days and information sessions but have training needs beyond this. Two projects were undertaken during 2007 and 2008. Refugee services in regional and rural NSW and their efficacy were reviewed, exploring models of care in four NSW locations and clarifying needs via a literature search. Training and resources available to caseworkers and volunteers were also investigated. The objective was to design and construct a basic manual addressing the needs of this workforce informed by a literature search and consultation with key stakeholders in refugee resettlement. Literature searches of electronic databases, relevant websites and journals informed the questions for participants of focus groups and semi-structured interviews. Additional data were obtained via self-report questionnaires from caseworkers, volunteers and mainstream agencies. Information was also disseminated to refugees, inviting community to participate in focus groups. Our study supported others noting difficulties associated with the settlement of refugees in regional Australia, and recommendations of improvements were developed using the social determinants of health. The supporting workforce encounters a multitude of issues when working with newly arrived refugees, including language barriers, client expectations and challenges in developing living skills. Workers reported that accessing refugees' information is time-consuming, and that available resources are fragmented. Refugees expressed frustration at being categorised but acknowledged the efforts of volunteers and caseworkers. Findings and feedback from the literature review, focus groups, consultations with resettlement stakeholders and interviews supported the concept of developing a basic manual and conversation-starter flashcards. The limitations of the developed manual are acknowledged, as is a need for agency specific information on common topics for volunteers, caseworkers and clients, is suggested. Volunteer and caseworker training should be expanded.

The analysis of benzodiazepines in forensic urine samples.

DOT National Transportation Integrated Search

1996-04-01

The FAA Toxicology and Accident Research Laboratory reports the presence of any drug detected at therapeutic or subtherapeutic levels and the medical condition for which the drug may have been used. Specimens from the pilot of a fatal aviation accide...

Use of egg yolk antibody (IgY) as an immunoanalytical tool in the detection of Indian cobra (Naja naja naja) venom in biological samples of forensic origin.

PubMed

Brunda, G; Sashidhar, R B; Sarin, R K

2006-08-01

An immunoglobulin Y (IgY) based indirect double antibody sandwich enzyme linked immunosorbent assay (ELISA) was developed for the detection of Indian cobra (Naja naja naja) venom in the biological samples of forensic origin. Polyclonal antibodies were raised and purified from chick egg yolk and rabbit serum. The cobra venom was sandwiched between immobilized affinity purified IgY and the rabbit IgG. The detection concentration of cobra venom was in the range of 0.1 to 300ng. The calibration plot was based on linear regression analysis (y=0.2581x+0.4375, r(2)=0.9886). The limit of detection of the assay was found to be 0.1ng. The coefficient of variation (CV) of different concentrations of working range in inter (n=6) and intra-assay (n=6) was observed to be less than 10%. The recovery of venom was found to be in the range of 80-99%, when different concentrations (0.002, 0.1, 0.2, 1, and 2microg) of cobra venom were spiked to pooled normal human serum (ml(-1)). No cross reactivity was observed with krait and viper venom in the immunoassay system in the concentration range of 0.1-1000ng. The method was initially, validated by analyzing specimens (autopsy) of experimental rats injected with cobra venom (1.2mgkg(-1) body mass). Further, human specimens (autopsy and biopsy) of snake bite victims of forensic origin were also analyzed. The methodology developed may find diagnostic application in forensic laboratories.

Taphonomic Analysis of Rodentia and Lagomorpha Bone Gnawing Based Upon Incisor Size.

PubMed

Pokines, James T; Sussman, Rachel; Gough, Megan; Ralston, Claira; McLeod, Elizabeth; Brun, Karen; Kearns, Aisling; Moore, Tara L

2017-01-01

Rodent and lagomorph species have a worldwide distribution and have the potential to alter remains from forensic cases by gnawing soft tissue and bones and through dispersal. The present research compiled metric data on the incisors widths of all rodent and lagomorph species whose ranges include Massachusetts, U.S.A., to compare their sizes to gnawing damage found on 17 cases of human remains from the Office of the Chief Medical Examiner, Boston, MA. Data on gnawing maximum striation widths also were collected from live laboratory, zoo, and wild specimens. Gnawing damage on the forensic cases could be attributed only to a particular size class of rodent or lagomorph, and identification to a particular species based on gnawing damage alone may be possible only in relatively rare cases. Multiple species examined here have broad distribution ranges, so their taphonomic alterations may impact bones from forensic cases throughout large portions of North America. © 2016 American Academy of Forensic Sciences.

Toxicological analysis of formalin-fixed or embalmed tissues: a review.

PubMed

Nikolaou, Panagiota; Papoutsis, Ioannis; Dona, Artemisia; Spiliopoulou, Chara; Athanaselis, Sotiris

2013-12-10

During the autopsy of forensic cases, when there is no suspicion of drug use or chemical exposure, biological fluids may not be obtained for toxicological analysis, while specimens of tissues may be collected and preserved in a formalin solution for histological examination. When specific questions arise after the burial, the only possible options are the exhumation of an embalmed body or the toxicological analysis of the formalin-fixed specimens. The drug concentrations in these specimens can be altered due to the extraction efficiency and/or the chemical activity of the formalin solutions used during chemical fixation or embalming process. The aim of this paper is to review the published studies about the determination of specific groups of drugs in formalin-fixed or embalmed specimens and their stability after chemical fixation or embalming process. The analytical aspects of this determination are also discussed. The stability of drugs in formalin environment and the possible reaction of the drugs with formaldehyde, which is a highly reactive chemical substance, should always be considered during post-mortem/post-embalming forensic analysis. The additional analysis of the formalin solution in which the tissue was preserved is considered necessary. The identification and the evaluation of the possible degradation products or chemical derivatives are extremely useful during the interpretation of the results. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

High-Performance Liquid Chromatography with Tandem Mass Spectrometry for the Determination of Nine Hallucinogenic 25-NBOMe Designer Drugs in Urine Specimens

PubMed Central

Poklis, Justin L.; Clay, Deborah J.; Poklis, Alphonse

2014-01-01

We present a high-performance liquid chromatography triple quadrupole mass spectrometry (HPLC–MS-MS) method for the identification and quantification of nine serotonin 5-HT2A receptor agonist hallucinogenic substances from a new class of N-methoxybenzyl derivatives of methoxyphenylethylamine (NBOMe) designer drugs in human urine: 25H-NBOMe, 2CC-NBOMe, 25I-NBF, 25D-NBOMe, 25B-NBOMe, 2CT-NBOMe, 25I-NBMD, 25G-NBOMe and 25I-NBOMe. This assay was developed for the Virginia Commonwealth University Clinical and Forensic Toxicology laboratory to screen emergency department specimens in response to an outbreak of N-benzyl-phenethylamine derivative abuse and overdose cases in Virginia. The NBOMe derivatives were rapidly extracted from the urine specimens by use of FASt™ solid-phase extraction columns. Assay performance was determined as recommended for validation by the Scientific Working Group for Forensic Toxicology (SWGTOX) for linearity, lower limit of quantification, lower limit of detection, accuracy/bias, precision, dilution integrity, carryover, selectivity, absolute recovery, ion suppression and stability. Linearity was verified to be from 1 to 100 ng/mL for each of the nine analytes. The bias determined for the NBOMe derivatives was 86–116% with a <14% coefficient of variation over the linear range of the assay. Four different NBOMe derivatives were detected using the presented method in patient urine specimens. PMID:24535338

The Effects of the ARC Organizational Intervention on Caseworker Turnover, Climate, and Culture in Children's Service Systems

ERIC Educational Resources Information Center

Glisson, Charles; Dukes, Denzel; Green, Philip

2006-01-01

Objective: This study examines the effects of the Availability, Responsiveness, and Continuity (ARC) organizational intervention strategy on caseworker turnover, climate, and culture in a child welfare and juvenile justice system. Method: Using a pre-post, randomized blocks, true experimental design, 10 urban and 16 rural case management teams…

Pilot-Reported Beta-Blockers Identified by Forensic Toxicology Analysis of Postmortem Specimens.

PubMed

Canfield, Dennis V; Dubowski, Kurt M; Whinnery, James M; Forster, Estrella M

2018-01-01

This study compared beta-blockers reported by pilots with the medications found by postmortem toxicology analysis of specimens received from fatal aviation accidents between 1999 and 2015. Several studies have compared drugs using the standard approach: Compare the drug found by toxicology analysis with the drug reported by the pilot. This study uniquely examined first the pilot-reported medication and then compared it to that detected by toxicology analysis. This study will serve two purposes: (i) to determine the capability of a toxicology laboratory to detect reported medications, and (ii) to identify pilots with medications below detectable limits. All information required for this study was extracted from the Toxicology Data Base system and was searched using ToxFlo or SQL Server Management Studio. The following information was collected and analyzed: pilot-reported trade and/or generic drug, date specimens received, time of accident, type of aviation operations (CFR), state, pilot level, age, class of medical, specimen type, specimen concentration, dose reported, frequency reported associated with the accident, quantity reported, National Transportation Safety Board (NTSB) accident event number, and all NTSB reports. There were 319 pilots that either reported taking a beta-blocker or were found to be taking a beta-blocker by postmortem toxicology analysis. Time of death, therapeutic concentration and specimen type were found to be factors in the ability of the laboratory to detect beta-blockers. Beta-blockers taken by pilots will, in most cases, be found by a competent postmortem forensic toxicology laboratory at therapeutic concentrations. The dose taken by the pilot was not found to be a factor in the ability of the laboratory to identify beta-blockers. Time of dose, route of administration, specimen tested and therapeutic concentration of the drug were found to be factors in the ability of the laboratory to identify beta-blockers in postmortem specimens. Published by Oxford University Press 2017. This work is written by (a) US Government employee(s) and is in the public domain in the US.

78 FR 56714 - Proposed Information Collection Activity; Comment Request

Federal Register 2010, 2011, 2012, 2013, 2014

2013-09-13

... Permanency Posttest........ CAFAS pretest 12 4 5 1.0 20 Caseworker discussion for 60 20 1 0.5 10 CAFAS pretest completion... CAFAS posttest 12 4 5 1.0 20 Caseworker discussion for 60 20 1 0.5 10 CAFAS posttest... permanency outcomes for particular groups of children and youth who are at risk for long- term foster care...

The Free-Form-Five (ff5): A Canadian "Casework" or Furniture and Equipment System for Schools. Programme on Educational Building 4.

ERIC Educational Resources Information Center

Lenssen, Paul

The fourth in a series of leaflets designed for dissemination of information on school building, this publication describes a caseworks subsystem consisting of storage systems, surface systems, plumbing and electrical services, and seating. The technical performance specifications for this subsystem and nine others were developed as a product of…

Facilitating Mental Health Service Use for Caregivers: Referral Strategies among Child Welfare Caseworkers.

PubMed

Bunger, Alicia C; Chuang, Emmeline; McBeath, Bowen

2012-04-01

Unmet needs for mental health care are common among caregivers involved in the child welfare system. Although child welfare caseworkers are well positioned to identify service needs and refer caregivers to treatment, little is known about the types of referral strategies used in practice, or their effectiveness for promoting mental health service use. The current study examined child welfare caseworkers' use of different referral strategies and the extent to which these strategies are associated with caregivers' receipt of mental health services within a national sample of child welfare cases. Analyses of the second cohort of families from the National Survey of Child and Adolescent Well-Being suggest that child welfare workers more often use informational strategies for referring caregivers, including suggesting treatment or providing information about treatment options. However, social referral strategies such as providing caregivers with direct assistance in completing applications and making and attending appointments were associated with a greater likelihood of caregivers receiving mental health services. Findings support evidence from other service contexts that service use is facilitated by caseworkers' direct support for arranging services. Implications for research and for child welfare managers and administrators are discussed.

Fatal cranial injury in an individual from Messina (Sicily) during the times of the Roman Empire.

PubMed

Messina, Andrea Dario; Carotenuto, Giuseppe; Miccichè, Roberto; Sìneo, Luca

2013-11-01

Forensic and archaeological examinations of human skeletons can provide us with evidence of violence. In this paper, we present the patterns of two cranial lesions found on an adult male (T173) buried in a grave in the necropolis 'Isolato 96', Messina, Sicily, dating back to the Roman Empire (1st century BC - 1st century AD). The skull reveals two perimortem traumatic lesions, one produced by a sharp object on the right parietal bone and the other one on the left parietal bone, presumably the result of a fall. The interpretation of fracture patterns found in this cranium are an illustration of how forensic approaches can be applied with great benefit to archaeological specimens. Copyright © 2013 Elsevier Ltd and Faculty of Forensic and Legal Medicine. All rights reserved.

Analytical Raman spectroscopy in a forensic art context: the non-destructive discrimination of genuine and fake lapis lazuli.

PubMed

Ali, Esam M A; Edwards, Howell G M

2014-01-01

The differentiation between genuine and fake lapis lazuli specimens using Raman spectroscopy is assessed using laboratory and portable instrumentation operating at two longer wavelengths of excitation in the near-infrared, namely 1064 and 785 nm. In spite of the differences between the spectra excited here in the near infrared and those reported in the literature using visible excitation, it is clear that Raman spectroscopy at longer wavelengths can provide a means of differentiating between the fakes studied here and genuine lapis lazuli. The Raman spectra obtained from portable instrumentation can also achieve this result, which will be relevant for the verification of specimens which cannot be removed from collections and for the identification of genuine lapis lazuli inlays in, for example, complex jewellery and furniture. The non-destructive and non-contact character of the technique offers a special role for portable Raman spectroscopy in forensic art analysis. Copyright © 2013 Elsevier B.V. All rights reserved.

A practical approach to determination of laboratory GC-MS limits of detection.

PubMed

Underwood, P J; Kananen, G E; Armitage, E K

1997-01-01

Determination of limit of detection (LOD) values in a forensic laboratory serves a fundamental forensic requirement for assay performance. In addition to demonstrating assay capability, LOD values can also be used to fulfill certification requirements of a high-volume forensic drug laboratory. The LOD was defined as the lowest concentration of drug that the laboratory can detect in a specimen with forensic certainty at a minimum of 85% of the time. Overall batch acceptance criteria included acceptable quantitation of control materials (within 20% of target), acceptable chromatography (symmetry, peak integration, peak shape, peak, and baseline resolution), retention time within +/-1% of the extracted standard, and mass ion ratios within +/-20% of the extracted standard mass ion ratios. Individual specimen acceptance criteria were the same as the batch acceptance criteria excluding the quantitation requirement. Data were collected from all instruments on different runs. A minimum of ten data points was required for each certified instrument, and a minimum of 85% of data points was acceptable. Quantitation within +/-20% of the LOD concentration was not required, but acceptable mass ratios were required. Data points with poor chromatography (internal standard failed mass ratios; interference of the baseline, for example, shoulders; asymmetry; and baseline resolution) was omitted from the acceptable rate calculation. Data points with good chromatography with failed mass ion ratios were included in the acceptable rate calculation. With these criteria, we established the following LODs: 11-nor-delta 9-tetrahydrocannabinol-9-carboxylic acid, 2 ng/mL; benzoylecgonine, 5 ng/mL; phencyclidine, 2.5 ng/mL; amphetamine, 150 ng/mL; methamphetamine, 100 ng/mL; codeine, 500 ng/mL; and morphine, 1000 ng/mL.

Purification of pharmaceutical preparations using thin-layer chromatography to obtain mass spectra with Direct Analysis in Real Time and accurate mass spectrometry.

PubMed

Wood, Jessica L; Steiner, Robert R

2011-06-01

Forensic analysis of pharmaceutical preparations requires a comparative analysis with a standard of the suspected drug in order to identify the active ingredient. Purchasing analytical standards can be expensive or unattainable from the drug manufacturers. Direct Analysis in Real Time (DART™) is a novel, ambient ionization technique, typically coupled with a JEOL AccuTOF™ (accurate mass) mass spectrometer. While a fast and easy technique to perform, a drawback of using DART™ is the lack of component separation of mixtures prior to ionization. Various in-house pharmaceutical preparations were purified using thin-layer chromatography (TLC) and mass spectra were subsequently obtained using the AccuTOF™- DART™ technique. Utilizing TLC prior to sample introduction provides a simple, low-cost solution to acquiring mass spectra of the purified preparation. Each spectrum was compared against an in-house molecular formula list to confirm the accurate mass elemental compositions. Spectra of purified ingredients of known pharmaceuticals were added to an in-house library for use as comparators for casework samples. Resolving isomers from one another can be accomplished using collision-induced dissociation after ionization. Challenges arose when the pharmaceutical preparation required an optimized TLC solvent to achieve proper separation and purity of the standard. Purified spectra were obtained for 91 preparations and included in an in-house drug standard library. Primary standards would only need to be purchased when pharmaceutical preparations not previously encountered are submitted for comparative analysis. TLC prior to DART™ analysis demonstrates a time efficient and cost saving technique for the forensic drug analysis community. Copyright © 2011 John Wiley & Sons, Ltd. Copyright © 2011 John Wiley & Sons, Ltd.

Statistical and population genetics issues of two Hungarian datasets from the aspect of DNA evidence interpretation.

PubMed

Szabolcsi, Zoltán; Farkas, Zsuzsa; Borbély, Andrea; Bárány, Gusztáv; Varga, Dániel; Heinrich, Attila; Völgyi, Antónia; Pamjav, Horolma

2015-11-01

When the DNA profile from a crime-scene matches that of a suspect, the weight of DNA evidence depends on the unbiased estimation of the match probability of the profiles. For this reason, it is required to establish and expand the databases that reflect the actual allele frequencies in the population applied. 21,473 complete DNA profiles from Databank samples were used to establish the allele frequency database to represent the population of Hungarian suspects. We used fifteen STR loci (PowerPlex ESI16) including five, new ESS loci. The aim was to calculate the statistical, forensic efficiency parameters for the Databank samples and compare the newly detected data to the earlier report. The population substructure caused by relatedness may influence the frequency of profiles estimated. As our Databank profiles were considered non-random samples, possible relationships between the suspects can be assumed. Therefore, population inbreeding effect was estimated using the FIS calculation. The overall inbreeding parameter was found to be 0.0106. Furthermore, we tested the impact of the two allele frequency datasets on 101 randomly chosen STR profiles, including full and partial profiles. The 95% confidence interval estimates for the profile frequencies (pM) resulted in a tighter range when we used the new dataset compared to the previously published ones. We found that the FIS had less effect on frequency values in the 21,473 samples than the application of minimum allele frequency. No genetic substructure was detected by STRUCTURE analysis. Due to the low level of inbreeding effect and the high number of samples, the new dataset provides unbiased and precise estimates of LR for statistical interpretation of forensic casework and allows us to use lower allele frequencies. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Bullet fragmentation preceding a contour shot: case study and experimental simulation.

PubMed

Sterzik, V; Kneubuehl, B P; Bohnert, M; Riva, F; Glardon, M

2017-01-01

In medico-legal literature, only a small number of publications deal with lethal injuries caused by shots with modified guns. This might lead to the conclusion that such cases are extremely rare. However, there are cases again and yet again. During the investigation process, the modified gun is of particular importance since it can show an unusual ballistic behaviour. The present paper reports on a suicide of a 60-year-old man, committed with a modified revolver and a lead bullet. The man had a single gunshot wound with entrance at the right temporal bone. Autopsy revealed that the bullet had fragmented into two major parts. The smaller one stood outside the cranial cavity and pushed its way alongside between the cranial bone and scalp to its end position in the left temporal area. The bigger part entered the cranial cavity and ended in the left parietal lobe. In shots on ballistic soap and on a head-model, the ballistics of the weapon and lead bullet were characterized. The angle necessary for bullet fragmentation was determined by shots on ballistic soap and turned out to be 55°-60° at a velocity of around 200 m/s. This knowledge was transferred to contact shots on a head-model consisting of a layered polyurethane sphere filled with 10 % ballistic gelatine and covered with a skin-like cap almost all around. The resulting injury pattern corresponded to the one of the suicide person. The bigger bullet part entered the skull while the smaller part pushed its way alongside between skin and skull causing an outer contour shot. Furthermore, the revolver was documented firing off two bullets by one trigger pull-a phenomenon of importance for forensic casework the authors have not found reported in forensic literature.

Age estimation in forensic sciences: application of combined aspartic acid racemization and radiocarbon analysis.

PubMed

Alkass, Kanar; Buchholz, Bruce A; Ohtani, Susumu; Yamamoto, Toshiharu; Druid, Henrik; Spalding, Kirsty L

2010-05-01

Age determination of unknown human bodies is important in the setting of a crime investigation or a mass disaster because the age at death, birth date, and year of death as well as gender can guide investigators to the correct identity among a large number of possible matches. Traditional morphological methods used by anthropologists to determine age are often imprecise, whereas chemical analysis of tooth dentin, such as aspartic acid racemization, has shown reproducible and more precise results. In this study, we analyzed teeth from Swedish individuals using both aspartic acid racemization and radiocarbon methodologies. The rationale behind using radiocarbon analysis is that aboveground testing of nuclear weapons during the cold war (1955-1963) caused an extreme increase in global levels of carbon-14 ((14)C), which has been carefully recorded over time. Forty-four teeth from 41 individuals were analyzed using aspartic acid racemization analysis of tooth crown dentin or radiocarbon analysis of enamel, and 10 of these were split and subjected to both radiocarbon and racemization analysis. Combined analysis showed that the two methods correlated well (R(2) = 0.66, p < 0.05). Radiocarbon analysis showed an excellent precision with an overall absolute error of 1.0 +/- 0.6 years. Aspartic acid racemization also showed a good precision with an overall absolute error of 5.4 +/- 4.2 years. Whereas radiocarbon analysis gives an estimated year of birth, racemization analysis indicates the chronological age of the individual at the time of death. We show how these methods in combination can also assist in the estimation of date of death of an unidentified victim. This strategy can be of significant assistance in forensic casework involving dead victim identification.

Age estimation in forensic sciences: Application of combined aspartic acid racemization and radiocarbon analysis

DOE Office of Scientific and Technical Information (OSTI.GOV)

Alkass, K; Buchholz, B A; Ohtani, S

Age determination of unknown human bodies is important in the setting of a crime investigation or a mass disaster, since the age at death, birth date and year of death, as well as gender, can guide investigators to the correct identity among a large number of possible matches. Traditional morphological methods used by anthropologists to determine age are often imprecise, whereas chemical analysis of tooth dentin, such as aspartic acid racemization has shown reproducible and more precise results. In this paper we analyze teeth from Swedish individuals using both aspartic acid racemization and radiocarbon methodologies. The rationale behind using radiocarbonmore » analysis is that above-ground testing of nuclear weapons during the cold war (1955-1963) caused an extreme increase in global levels of carbon-14 ({sup 14}C) which have been carefully recorded over time. Forty-four teeth from 41 individuals were analyzed using aspartic acid racemization analysis of tooth crown dentin or radiocarbon analysis of enamel and ten of these were split and subjected to both radiocarbon and racemization analysis. Combined analysis showed that the two methods correlated well (R2=0.66, p < 0.05). Radiocarbon analysis showed an excellent precision with an overall absolute error of 0.6 {+-} 04 years. Aspartic acid racemization also showed a good precision with an overall absolute error of 5.4 {+-} 4.2 years. Whereas radiocarbon analysis gives an estimated year of birth, racemization analysis indicates the chronological age of the individual at the time of death. We show how these methods in combination can also assist in the estimation of date of death of an unidentified victim. This strategy can be of significant assistance in forensic casework involving dead victim identification.« less

Elemental analysis of forensic glasses by inductively coupled plasma mass spectrometry

NASA Astrophysics Data System (ADS)

Almirall, Jose R.; Duckworth, Douglas C.; Bayne, Charles K.; Morton, Sherman A.; Smith, David H.; Koons, Robert D.; Furton, Kenneth G.

1999-02-01

Flat glass is a common type of evidence collected from the scenes of crimes such as burglaries, vandalism, and hit-and- run accidents. The usefulness of such evidence lies in the ability to associate the glass from the scene (or a suspect) to the original source. Physical and chemical analysis of the glass can be used for discrimination between the possible sources of glass. If the sample is large enough, physical attributes such as fracture matches, density, color, and thickness can be employed for comparison between a recovered fragment(s) to the suspect source. More commonly, refractive index (RI) comparisons are employed. Due to the improved control over glass manufacturing processes, RI values often cannot differentiate glasses where approximately 6 - 9% of casework samples are not expected to be distinguished by RI alone even if they originated from different sources. Employing methods such as NAA, XRF, ICP-AES, and ICP-MS for the comparison of trace elemental compositions has been shown to be more discriminating than RI comparisons. The multielement capability and the sensitivity of ICP-AES and ICP-MS provide for excellent discrimination power. In this work, the sources of variability in ICP-MS of glass analysis are investigated to determine possible sources of variation. The sources of variation examined include errors due to sample preparation, instrument accuracy and precision, and interlaboratory reproducibility. Other sources of variation include inhomogeneity across a sheet of glass from the same source. Analysis of variance has been applied to our ICP-MS analysis of NIST standards and to the interlaboratory comparisons of float glass samples collected across a sheet in a production facility. The results of these experiments allows for a more accurate interpretation of forensic glass data and a better understanding of the discriminating power (absolute and practical) of ICP-MS.

Age Estimation in Forensic Sciences

PubMed Central

Alkass, Kanar; Buchholz, Bruce A.; Ohtani, Susumu; Yamamoto, Toshiharu; Druid, Henrik; Spalding, Kirsty L.

2010-01-01

Age determination of unknown human bodies is important in the setting of a crime investigation or a mass disaster because the age at death, birth date, and year of death as well as gender can guide investigators to the correct identity among a large number of possible matches. Traditional morphological methods used by anthropologists to determine age are often imprecise, whereas chemical analysis of tooth dentin, such as aspartic acid racemization, has shown reproducible and more precise results. In this study, we analyzed teeth from Swedish individuals using both aspartic acid racemization and radiocarbon methodologies. The rationale behind using radiocarbon analysis is that aboveground testing of nuclear weapons during the cold war (1955–1963) caused an extreme increase in global levels of carbon-14 (14C), which has been carefully recorded over time. Forty-four teeth from 41 individuals were analyzed using aspartic acid racemization analysis of tooth crown dentin or radiocarbon analysis of enamel, and 10 of these were split and subjected to both radiocarbon and racemization analysis. Combined analysis showed that the two methods correlated well (R2 = 0.66, p < 0.05). Radiocarbon analysis showed an excellent precision with an overall absolute error of 1.0 ± 0.6 years. Aspartic acid racemization also showed a good precision with an overall absolute error of 5.4 ± 4.2 years. Whereas radiocarbon analysis gives an estimated year of birth, racemization analysis indicates the chronological age of the individual at the time of death. We show how these methods in combination can also assist in the estimation of date of death of an unidentified victim. This strategy can be of significant assistance in forensic casework involving dead victim identification. PMID:19965905

GHB Pharmacology and Toxicology: Acute Intoxication, Concentrations in Blood and Urine in Forensic Cases and Treatment of the Withdrawal Syndrome

PubMed Central

Busardò, Francesco P.; Jones, Alan W.

2015-01-01

The illicit recreational drug of abuse, γ-hydroxybutyrate (GHB) is a potent central nervous system depressant and is often encountered during forensic investigations of living and deceased persons. The sodium salt of GHB is registered as a therapeutic agent (Xyrem®), approved in some countries for the treatment of narcolepsy-associated cataplexy and (Alcover®) is an adjuvant medication for detoxification and withdrawal in alcoholics. Trace amounts of GHB are produced endogenously (0.5-1.0 mg/L) in various tissues, including the brain, where it functions as both a precursor and a metabolite of the major inhibitory neurotransmitter γ-aminobutyric acid (GABA). Available information indicates that GHB serves as a neurotransmitter or neuromodulator in the GABAergic system, especially via binding to the GABA-B receptor subtype. Although GHB is listed as a controlled substance in many countries abuse still continues, owing to the availability of precursor drugs, γ-butyrolactone (GBL) and 1,4-butanediol (BD), which are not regulated. After ingestion both GBL and BD are rapidly converted into GHB (t½ ~1 min). The Cmax occurs after 20-40 min and GHB is then eliminated from plasma with a half-life of 30-50 min. Only about 1-5% of the dose of GHB is recoverable in urine and the window of detection is relatively short (3-10 h). This calls for expeditious sampling when evidence of drug use and/or abuse is required in forensic casework. The recreational dose of GHB is not easy to estimate and a concentration in plasma of ~100 mg/L produces euphoria and disinhibition, whereas 500 mg/L might cause death from cardiorespiratory depression. Effective antidotes to reverse the sedative and intoxicating effects of GHB do not exist. The poisoned patients require supportive care, vital signs should be monitored and the airways kept clear in case of emesis. After prolonged regular use of GHB tolerance and dependence develop and abrupt cessation of drug use leads to unpleasant withdrawal symptoms. There is no evidence-based protocol available to deal with GHB withdrawal, apart from administering benzodiazepines. PMID:26074743

Testing of microsatellite multiplexes for individual identification of Cape Parrots (Poicephalus robustus): paternity testing and monitoring trade

PubMed Central

Coetzer, Willem G.; Downs, Colleen T.; Perrin, Mike R.

2017-01-01

Background Illegal trade in rare wildlife species is a major threat to many parrot species around the world. Wildlife forensics plays an important role in the preservation of endangered or threatened wildlife species. Identification of illegally harvested or traded animals through DNA techniques is one of the many methods used during forensic investigations. Natural populations of the South African endemic Cape Parrot (Poicephalus robustus) are negatively affected by the removal of eggs and chicks for the pet trade. Methods In this study, 16 microsatellite markers specifically designed for the South African endemic Cape Parrot (P. robustus) are assessed for their utility in forensic casework. Using these 16 loci, the genetic diversity of a subset of the captive Cape Parrot population was also assessed and compared to three wild Cape Parrot populations. Results It was determined that the full 16 locus panel has sufficient discriminatory power to be used in parentage analyses and can be used to determine if a bird has been bred in captivity and so can be legally traded or if it has been illegally removed from the wild. In cases where birds have been removed from the wild, this study suggests that a reduced 12 locus microsatellite panel has sufficient power to assign confiscated birds to geographic population of origin. Discussion The level of genetic diversity observed within the captive Cape Parrot population was similar to that observed in the wild populations, which suggests that the captive population is not suffering from decreased levels of genetic diversity. The captive Cape Parrots did however have double the number of private alleles compared to that observed in the most genetically diverse wild population. This is probably due to the presence of rare alleles present in the founder population, which has not been lost due to genetic drift, as many of the individuals tested in this study are F1–F3 wild descendants. The results from this study provide a suit of markers that can be used to aid conservation and law enforcement authorities to better control legal and illegal trade of this South African endemic. PMID:28344897

DNA methylation profiling for a confirmatory test for blood, saliva, semen, vaginal fluid and menstrual blood.

PubMed

Lee, Hwan Young; Jung, Sang-Eun; Lee, Eun Hee; Yang, Woo Ick; Shin, Kyoung-Jin

2016-09-01

The ability to predict the type of tissues or cells from molecular profiles of crime scene samples has important practical implications in forensics. A previously reported multiplex assay using DNA methylation markers could only discriminate between 4 types of body fluids: blood, saliva, semen, and the body fluid which originates from female reproductive organ. In the present study, we selected 15 menstrual blood-specific CpG marker candidates based on analysis of 12 genome-wide DNA methylation profiles of vaginal fluid and menstrual blood. The menstrual blood-specificity of the candidate markers was confirmed by comparison with HumanMethylation450 BeadChip array data obtained for 58 samples including 12 blood, 12 saliva, 12 semen, 3 vaginal fluid, and 19 skin epidermis samples. Among 15CpG marker candidates, 3 were located in the promoter region of the SLC26A10 gene, and 2 of them (cg09696411 and cg18069290) showed high menstrual blood specificity. DNA methylation at the 2CpG markers was further tested by targeted bisulfite sequencing of 461 additional samples including 49 blood, 52 saliva, 34 semen, 125 vaginal fluid, and 201 menstrual blood. Because the 2 markers showed menstrual blood-specific methylation patterns, we modified our previous multiplex methylation SNaPshot reaction to include these 2 markers. In addition, a blood marker cg01543184 with cross reactivity to semen was replaced with cg08792630, and a semen-specific unmethylation marker cg17621389 was removed. The resultant multiplex methylation SNaPshot allowed positive identification of blood, saliva, semen, vaginal fluid and menstrual blood using the 9CpG markers which show a methylation signal only in the target body fluids. Because of the complexity in cell composition, menstrual bloods produced DNA methylation profiles that vary with menstrual cycle and sample collection methods, which are expected to provide more insight into forensic menstrual blood test. Moreover, because the developed multiplex methylation SNaPshot reaction includes the 4CpG markers of which specificities have been confirmed by multiple studies, it will facilitate confirmatory tests for body fluids that are frequently observed in forensic casework. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Interpretation of postmortem forensic toxicology results for injury prevention research.

PubMed

Drummer, Olaf H; Kennedy, Briohny; Bugeja, Lyndal; Ibrahim, Joseph Elias; Ozanne-Smith, Joan

2013-08-01

Forensic toxicological data provides valuable insight into the potential contribution of alcohol and drugs to external-cause deaths. There is a paucity of material that guides injury researchers on the principles that need to be considered when examining the presence and contribution of alcohol and drugs to these deaths. This paper aims to describe and discuss strengths and limitations of postmortem forensic toxicology sample selection, variations in analytical capabilities and data interpretation for injury prevention research. Issues to be considered by injury researchers include: the circumstances surrounding death (including the medical and drug use history of the deceased person); time and relevant historical factors; postmortem changes (including redistribution and instability); laboratory practices; specimens used; drug concentration; and attribution of contribution to death. This paper describes the range of considerations for testing and interpreting postmortem forensic toxicology, particularly when determining impairment or toxicity as possible causal factors in injury deaths. By describing these considerations, this paper has application to decisions about study design and case inclusion in injury prevention research, and to the interpretation of research findings.

Sex determination from calcification of costal cartilages in a Scottish sample.

PubMed

Middleham, Helen P; Boyd, Laura E; Mcdonald, Stuart W

2015-10-01

The pelvic bones and skull are not always available when human remains are discovered in a forensic setting. This study investigates the suitability to a Scottish sample of existing methods of sexing based on calcification patterns in the costal cartilages. Radiographs of chest plates of 41 cadavers, 22 male and 19 female aged 57-96 years were analyzed for their calcification patterns according to the methods of McCormick et al. (1985, Am. J. Phys. Anthropol. 68:173-195) and Rejtarova et al. (2004, Biomed. Pap. Med. Fac. Univ. Palacky. Olomouc. Czech. Repub. 148:241-243). With the method of Rejtarova et al. (2004, Biomed. Pap. Med. Fac. Univ. Palacky. Olomouc. Czech. Repub. 148:241-243) none of the male specimens was sexed correctly. Of the chest plates that were suitable for sexing, the method of McCormick et al. (1985, Am. J. Phys. Anthropol. 68:173-195) correctly sexed 82.4% of the female specimens but only 41.2% of the males. To improve the reliability, we suggest a new method of sex determination based on whether the calcified deposits in the second to seventh costal cartilages are predominantly trabecular bone or sclerotic calcified deposits. Specimens with minimal amounts or similar amounts of trabecular bone or sclerotic deposits in the costal cartilages are not appropriate for our method. When such specimens (10 specimens) were excluded, our method correctly sexed 16 of 17 (94%) males and 12 of 14 (86%) females. The authors acknowledge that their sample is small and that many of their subjects were elderly and that the method should be tested on a larger sample group before application in a forensic context. © 2014 Wiley Periodicals, Inc.

Using the Developmental Gene Bicoid to Identify Species of Forensically Important Blowflies (Diptera: Calliphoridae)

PubMed Central

Park, Seong Hwan; Park, Chung Hyun; Zhang, Yong; Piao, Huguo; Chung, Ukhee; Kim, Seong Yoon; Ko, Kwang Soo; Yi, Cheong-Ho; Jo, Tae-Ho; Hwang, Juck-Joon

2013-01-01

Identifying species of insects used to estimate postmortem interval (PMI) is a major subject in forensic entomology. Because forensic insect specimens are morphologically uniform and are obtained at various developmental stages, DNA markers are greatly needed. To develop new autosomal DNA markers to identify species, partial genomic sequences of the bicoid (bcd) genes, containing the homeobox and its flanking sequences, from 12 blowfly species (Aldrichina grahami, Calliphora vicina, Calliphora lata, Triceratopyga calliphoroides, Chrysomya megacephala, Chrysomya pinguis, Phormia regina, Lucilia ampullacea, Lucilia caesar, Lucilia illustris, Hemipyrellia ligurriens and Lucilia sericata; Calliphoridae: Diptera) were determined and analyzed. This study first sequenced the ten blowfly species other than C. vicina and L. sericata. Based on the bcd sequences of these 12 blowfly species, a phylogenetic tree was constructed that discriminates the subfamilies of Calliphoridae (Luciliinae, Chrysomyinae, and Calliphorinae) and most blowfly species. Even partial genomic sequences of about 500 bp can distinguish most blowfly species. The short intron 2 and coding sequences downstream of the bcd homeobox in exon 3 could be utilized to develop DNA markers for forensic applications. These gene sequences are important in the evolution of insect developmental biology and are potentially useful for identifying insect species in forensic science. PMID:23586044

Building bridges between clinical and forensic toxicology laboratories.

PubMed

Martin, Bernardino Barcelo; Gomila, Isabel; Noce, Valeria

2018-05-09

Clinical and forensic toxicology can be defined as the two disciplines involved the detection, identification and measurement of xenobiotics in biological and non-biological specimens to help in the diagnosis, treatment, prognosis, prevention of poisonings and to disclose causes and contributory causes of fatal intoxications, respectively. This article explores the close connections between clinical and forensic toxicology in overlapping areas of interest. An update has been carried out of the following seven areas of interest in analytical toxicology: doping control, sudden cardiac death (SCD), brain death, sudden infant death syndrome (SIDS) and Munchausen syndrome by proxy (MSBP), prenatal exposure to drugs and fetal alcohol syndrome (FAS), drug-facilitated crimes (DFC) and intoxications by new psychoactive substances (NPS). While issues such as SCD, SIDS or doping control are investigated mainly in forensic laboratories, other as prenatal exposure to drugs or FAS are mainly treated in clinical laboratories. On the other hand, areas such MSBP, DFC or the intoxications by NPS are of interest in both laboratories. Some of these topics are initially treated in hospital emergency departments, involving clinical laboratories and sometimes lately derived to forensic laboratories. Conversely, cases with initial medical-legal implications and fatalities are directly handled by forensic toxicology, but may trigger further studies in the clinical setting. Many areas of common interest between clinical and forensic laboratories are building bridges between them. The increasing relationships are improving the growth, the reliability and the robustness of both kind of laboratories. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

Short-read, high-throughput sequencing technology for STR genotyping

PubMed Central

Bornman, Daniel M.; Hester, Mark E.; Schuetter, Jared M.; Kasoji, Manjula D.; Minard-Smith, Angela; Barden, Curt A.; Nelson, Scott C.; Godbold, Gene D.; Baker, Christine H.; Yang, Boyu; Walther, Jacquelyn E.; Tornes, Ivan E.; Yan, Pearlly S.; Rodriguez, Benjamin; Bundschuh, Ralf; Dickens, Michael L.; Young, Brian A.; Faith, Seth A.

2013-01-01

DNA-based methods for human identification principally rely upon genotyping of short tandem repeat (STR) loci. Electrophoretic-based techniques for variable-length classification of STRs are universally utilized, but are limited in that they have relatively low throughput and do not yield nucleotide sequence information. High-throughput sequencing technology may provide a more powerful instrument for human identification, but is not currently validated for forensic casework. Here, we present a systematic method to perform high-throughput genotyping analysis of the Combined DNA Index System (CODIS) STR loci using short-read (150 bp) massively parallel sequencing technology. Open source reference alignment tools were optimized to evaluate PCR-amplified STR loci using a custom designed STR genome reference. Evaluation of this approach demonstrated that the 13 CODIS STR loci and amelogenin (AMEL) locus could be accurately called from individual and mixture samples. Sensitivity analysis showed that as few as 18,500 reads, aligned to an in silico referenced genome, were required to genotype an individual (>99% confidence) for the CODIS loci. The power of this technology was further demonstrated by identification of variant alleles containing single nucleotide polymorphisms (SNPs) and the development of quantitative measurements (reads) for resolving mixed samples. PMID:25621315

Ultra Performance Liquid Chromatography with Tandem Mass Spectrometry for the Quantitation of Seventeen Sedative Hypnotics in Six Common Toxicological Matrices.

PubMed

Mata, Dani C; Davis, John F; Figueroa, Ariana K; Stanford, Mary June

2016-01-01

An ultra performance liquid chromatography triple quadrupole mass spectrometry (LC-MS-MS) method for the quantification of 14 benzodiazepines and three sedative hypnotics is presented. The fast and inexpensive assay was developed for California's Orange County Crime Lab for use in antemortem (AM) and postmortem casework. The drugs were rapidly cleaned up from AM blood, postmortem blood, urine, liver, brain and stomach contents using DPX(®) Weak Anion Exchange (DPX WAX) tips fitted on a pneumatic extractor, which can process up to 48 samples at one time. Assay performance was determined for validation based on recommendations by the Scientific Working Group for Forensic Toxicology for linearity, limit of quantitation, limit of detection, bias, precision (within run and between run), dilution integrity, carry-over, selectivity, recovery, ion suppression and extracted sample stability. Linearity was verified using the therapeutic and toxic ranges of all 17 analytes. Final verification of the method was confirmed by four analysts using 20 blind matrix matched samples. All results were within 20% of each other and the expected value. © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Caseworker-recipient interaction: welfare office differences, economic trajectories, and child outcomes.

PubMed

Godfrey, Erin B; Yoshikawa, Hirokazu

2012-01-01

Drawing on developmental and policy research, this study examined whether 3 dimensions of caseworker-recipient interaction in welfare offices functioned as critical ecological contexts for recipient families. The sample consisted of 1,098 families from 10 welfare offices in National Evaluation of Welfare to Work Strategies (NEWWS). In multilevel analyses, caseworker support, caseload size, and emphasis on employment predicted 5-year quarterly trajectories of earnings, income, and welfare receipt. Recipients in offices characterized by high support had steeper increases in earnings and income; those in offices with high caseload size had steeper decreases in income and welfare receipt; and those in offices with high emphasis on employment had steeper decreases in welfare receipt. These economic trajectories were associated with children's reading and math achievement and internalizing behavior at ages 8-10. © 2011 The Authors. Child Development © 2011 Society for Research in Child Development, Inc.

Duragesic transdermal patch: postmortem tissue distribution of fentanyl in 25 cases.

PubMed

Anderson, D T; Muto, J J

2000-10-01

Fentanyl is a potent, short-acting narcotic analgesic widely used as a surgical anesthetic and for the control of pain when administered in the form of a transdermal patch. The success of the patch can be attributed to fentanyl's low molecular weight and its highly lipophilic nature, which enables it to be readily absorbed through the skin and subsequently distributed throughout the body. Over the past three years, the Los Angeles County Coroner's Toxicology Laboratory has encountered 25 cases involving Duragesic patches (fentanyl), and their postmortem tissue distributions are presented here. The analysis of fentanyl from postmortem specimens (3-mL or g sample size) consisted of an n-butyl chloride basic extraction followed by identification and quantitation on a gas chromatograph-mass spectrometer using the selected ion monitoring (SIM) mode. The fentanyl ions monitored were m/z 245, 146, and 189 and the internal standard, fentanyl-d5 ions, were m/z 250, 151, and 194 (quantitation ion underlined). The linear range of the assay was 1.67 microg/L to 500 microg/L with the limit of quantitation and detection of 1.67 microg/L. The postmortem tissue distribution ranges of fentanyl in the 25 fatalities were as follows: heart blood, 1.8-139 microg/L (23 cases); femoral blood, 3.1-43 microg/L (13 cases); vitreous, +<2.0-20 microg/L (4 cases); liver, 5.8-613 microg/kg (22 cases); bile, 3.5-262 microg/L (15 cases); urine, 2.9-895 microg/L (19 cases); gastric, 0-1200 microg total (17 cases); spleen, 7.8-79 microg/kg (3 cases); kidney, 11 microg/kg (1 case); and lung, 31 microg/kg (1 case). The age of the decedents in this study ranged from 19 to 84, with an average age of 46. The modes of death included 15 accidental, 5 natural, 3 suicidal, and 2 undetermined. The main objectives of this paper are to show the prevalence of fentanyl patches in our community and to aid the forensic toxicologist with the interpretation of postmortem fentanyl levels in casework.

Optimized mtDNA Control Region Primer Extension Capture Analysis for Forensically Relevant Samples and Highly Compromised mtDNA of Different Age and Origin

PubMed Central

Eduardoff, Mayra; Xavier, Catarina; Strobl, Christina; Casas-Vargas, Andrea; Parson, Walther

2017-01-01

The analysis of mitochondrial DNA (mtDNA) has proven useful in forensic genetics and ancient DNA (aDNA) studies, where specimens are often highly compromised and DNA quality and quantity are low. In forensic genetics, the mtDNA control region (CR) is commonly sequenced using established Sanger-type Sequencing (STS) protocols involving fragment sizes down to approximately 150 base pairs (bp). Recent developments include Massively Parallel Sequencing (MPS) of (multiplex) PCR-generated libraries using the same amplicon sizes. Molecular genetic studies on archaeological remains that harbor more degraded aDNA have pioneered alternative approaches to target mtDNA, such as capture hybridization and primer extension capture (PEC) methods followed by MPS. These assays target smaller mtDNA fragment sizes (down to 50 bp or less), and have proven to be substantially more successful in obtaining useful mtDNA sequences from these samples compared to electrophoretic methods. Here, we present the modification and optimization of a PEC method, earlier developed for sequencing the Neanderthal mitochondrial genome, with forensic applications in mind. Our approach was designed for a more sensitive enrichment of the mtDNA CR in a single tube assay and short laboratory turnaround times, thus complying with forensic practices. We characterized the method using sheared, high quantity mtDNA (six samples), and tested challenging forensic samples (n = 2) as well as compromised solid tissue samples (n = 15) up to 8 kyrs of age. The PEC MPS method produced reliable and plausible mtDNA haplotypes that were useful in the forensic context. It yielded plausible data in samples that did not provide results with STS and other MPS techniques. We addressed the issue of contamination by including four generations of negative controls, and discuss the results in the forensic context. We finally offer perspectives for future research to enable the validation and accreditation of the PEC MPS method for final implementation in forensic genetic laboratories. PMID:28934125

Relationship of spermatoscopy, prostatic acid phosphatase activity and prostate-specific antigen (p30) assays with further DNA typing in forensic samples from rape cases.

PubMed

Romero-Montoya, Lydia; Martínez-Rodríguez, Hugo; Pérez, Miguel Antonio; Argüello-García, Raúl

2011-03-20

In the forensic laboratory the biological analyses for rape investigation commonly include vaginal swabs as sample material combined to biochemical tests including sperm cytology (SC) and detection of acid phosphatase activity (AP) and prostate-specific antigen (PSA, p30) for the conclusive identification of semen components. Most reports comparing these tests relied on analysis of semen samples or donor swabs taken under controlled conditions; however their individual or combined efficacy under real live sampling conditions in different laboratories is largely unknown. We carried out SC, APA and PSA analyses in vaginal swabs collected from casework rapes submitted to Mexican Forensic Laboratories at Texcoco and Toluca. On the basis of positive and negative results from each assay and sample, data were classified into eight categories (I-VIII) and compared with those obtained in the two only similar studies reported in Toronto, Canada and Hong Kong, China. SC and APA assays had the higher overall positivity in Toluca and Texcoco samples respectively and otherwise PSA had a lower but very similar positivity between these two laboratories. When compared to the previous studies some similarities were found, namely similar frequencies (at a ratio of approximately 1 out of 3) of samples being positive or negative by all techniques (Categories I and VI respectively) and a comparable overall positivity of APA and SC but higher than that of PSA. Indeed the combined results of using SC, APA and PSA tests was considered as conclusive for semen detection from approximately 1 out of 3 cases (Category I) to approximately 1 out of 2 cases in a scenario where at least SC is positive, strongly presumptive in 2 out of 3 cases (with at least one test positive) and the remainder 1 out of 3 cases (Category VI) suggested absence of semen. By determining Y-STR polymorphisms (12-loci) in additional samples obtained at Toluca laboratory, complete DNA profiles were determined from all Category I samples, none marker was detected from all Category VI samples and mostly partial profiles were obtained from samples of other categories. These observations give an overview on the variability in efficacy of each test performed at different laboratories and provide a general notion about the in praxis contribution of SC, APA and PSA tests for further DNA typing in the forensic analysis of rape. Copyright © 2010 Elsevier Ireland Ltd. All rights reserved.

Rapid DNA analysis for automated processing and interpretation of low DNA content samples.

PubMed

Turingan, Rosemary S; Vasantgadkar, Sameer; Palombo, Luke; Hogan, Catherine; Jiang, Hua; Tan, Eugene; Selden, Richard F

2016-01-01

Short tandem repeat (STR) analysis of casework samples with low DNA content include those resulting from the transfer of epithelial cells from the skin to an object (e.g., cells on a water bottle, or brim of a cap), blood spatter stains, and small bone and tissue fragments. Low DNA content (LDC) samples are important in a wide range of settings, including disaster response teams to assist in victim identification and family reunification, military operations to identify friend or foe, criminal forensics to identify suspects and exonerate the innocent, and medical examiner and coroner offices to identify missing persons. Processing LDC samples requires experienced laboratory personnel, isolated workstations, and sophisticated equipment, requires transport time, and involves complex procedures. We present a rapid DNA analysis system designed specifically to generate STR profiles from LDC samples in field-forward settings by non-technical operators. By performing STR in the field, close to the site of collection, rapid DNA analysis has the potential to increase throughput and to provide actionable information in real time. A Low DNA Content BioChipSet (LDC BCS) was developed and manufactured by injection molding. It was designed to function in the fully integrated Accelerated Nuclear DNA Equipment (ANDE) instrument previously designed for analysis of buccal swab and other high DNA content samples (Investigative Genet. 4(1):1-15, 2013). The LDC BCS performs efficient DNA purification followed by microfluidic ultrafiltration of the purified DNA, maximizing the quantity of DNA available for subsequent amplification and electrophoretic separation and detection of amplified fragments. The system demonstrates accuracy, precision, resolution, signal strength, and peak height ratios appropriate for casework analysis. The LDC rapid DNA analysis system is effective for the generation of STR profiles from a wide range of sample types. The technology broadens the range of sample types that can be processed and minimizes the time between sample collection, sample processing and analysis, and generation of actionable intelligence. The fully integrated Expert System is capable of interpreting a wide range or sample types and input DNA quantities, allowing samples to be processed and interpreted without a technical operator.

Assessment of the stability of DNA in specimens collected under conditions for drug testing-A pilot study.

PubMed

White, Robert M; Mitchell, John M; Hart, E Dale; Evans, Amy; Meaders, Meredith; Norsworthy, Sarah E; Hayes, Eugene D; Flegel, Ron; Maha, George C; Shaffer, Megan D; Hall, Erin M; Rogers, Kelley

2018-02-01

For forensic biological sample collections, the specimen donor is linked solidly to his or her specimen through a chain of custody (CoC) sometimes referenced as a chain of evidence. Rarely, a donor may deny that a urine or oral fluid (OF) specimen is his or her specimen even with a patent CoC. The goal of this pilot study was to determine the potential effects of short-term storage on the quality and quantity of DNA in both types of specimen under conditions that may be encountered with employment-related drug testing specimens. Fresh urine and freshly collected oral fluid all produced complete STR profiles. For the "pad" type OF collectors, acceptable DNA was extractable both from the buffer/preservative and the pad. Although fresh urine and OF produced complete STR profiles, partial profiles were obtained after storage for most samples. An exception was the DNA in the Quantisal OF collector, from which a complete profile was obtained for both freshly collected OF and stored OF. Copyright © 2017 Elsevier B.V. All rights reserved.

Decomposition and dipteran succession in pig carrion in central Argentina: ecological aspects and their importance in forensic science.

PubMed

Horenstein, M Battán; Linhares, A Xavier; De Ferradas, B Rosso; García, D

2010-03-01

Data on the insect species associated with corpse decomposition are particularly important for estimation of the post-mortem interval (PMI) in forensic science because the PMI is based on the lifecycle and behaviour of necrophagous insects, among other measures. To determine the dipteran succession on pig carrion, four experiments, one in each season, were carried out during 2004 in a rural area of Córdoba, central Argentina. Two pigs (Sus scrofa L.) were used in each of the four experiments. At each time-point one pig was placed in the shade and the other under direct sunlight. Insects were collected daily during the first 4 weeks and thereafter every 2 or 3 days. Five stages of decomposition were observed and a total of 24 710 adult specimens were collected, belonging to the following eight families of Diptera: Calliphoridae; Muscidae; Sarcophagidae; Phoridae; Piophilidae; Fanniidae; Sphaeroceridae, and Anthomyiidae. All Calliphoridae collected in this study were considered to be of potential forensic importance because of their necrophagous behaviour and because their immature stages use carrion as a food source. Other species, such as Musca domestica L. and Ophyra aenescens (Wiedemann), were also considered to represent potential forensic indicators.

Exploitation of very small particles to enhance the probative value of carpet fibers.

PubMed

Stoney, David A; Neumann, Cedric; Mooney, Kim E; Wyatt, J Matney; Stoney, Paul L

2015-07-01

Environmentally acquired very small particles (VSP), present on the surfaces of carpet fibers, have shown potential for the association of fibers with their carpet source. To unlock this potential, research is required addressing a number of areas, including the application of methods under realistic casework conditions and the utilization of computational methods for the refinement and testing of the approach. In this work field collections of carpet fibers were conducted by crime scene practitioners under realistic casework conditions. VSP were isolated using previously developed methods, and analyses were conducted using SEM/EDS analytical protocols in an operational crime laboratory setting. Computational methods were designed, allowing sets of hundreds to thousands of VSP to be characterized. Classifiers were designed to associate and discriminate among specimens. These classifiers were applied to the VSP data for specimens collected by crime scene practitioners, as well as to a previously collected research dataset. Quantitative measures of correspondence and probative value were designed based on the classification measures and successfully applied to both sets of VSP data. Particle sets larger than 500 showed strong promise for quantitative associations with their sources. The use of larger numbers of target particle types (TPTs) showed strong promise to improve the performance of classification and association. Overall, the usefulness of VSP to provide objective, quantitative associations has been established. Because VSP are acquired post-manufacture, these methods can address fundamental limitations to probative value that arise when class characteristics, determined by manufacture, are shared among mass produced commodities. These findings are of broad significance for the future of trace evidence analysis. The results of this research are likely extendable, with minor modifications, to other trace evidence types (such as glass, tape and human hair), and are expected to contribute significantly for those types of trace evidence that have long been considered of low evidential value (such as undyed cotton and animal hairs). Furthermore, entirely new approaches to trace evidence are enabled by exploiting VSP profiles, such as comparing different types of trace evidence with one another and comparing VSP defined by crime scene or suspect environments to those on virtually any item of physical evidence. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Diagnostic Raman spectroscopy for the forensic detection of biomaterials and the preservation of cultural heritage.

PubMed

Edwards, Howell G M; Munshi, Tasnim

2005-07-01

This paper reviews the contributions of analytical Raman spectroscopy to the non-destructive characterisation of biological materials of relevance to forensic science investigations, including the sourcing of resins and the identification of the biodegradation of art and archaeological artefacts. The advantages of Raman spectroscopy for non-destructive analysis are well-appreciated; however, the ability to record molecular information about organic and inorganic species present in a heterogeneous specimen at the same time, the insensitivity of the Raman scattering process to water and hydroxyl groups, which removes the necessity for sample desiccation, and the ease of illumination for samples of very small and very large sizes and unusual shapes are also apparent. Several examples are used to illustrate the application of Raman spectroscopic techniques to the characterisation of forensic biomaterials and for the preservation of cultural heritage through case studies in the following areas: wall-paintings and rock art, human and animal tissues and skeletal remains, fabrics, resins and ivories.

Blow Flies from Forest Fragments Embedded in Different Land Uses: Implications for Selecting Indicators in Forensic Entomology.

PubMed

de Souza, Mirian S; Pepinelli, Mateus; de Almeida, Eduardo C; Ochoa-Quintero, Jose M; Roque, Fabio O

2016-01-01

Given the general expectation that forest loss can alter biodiversity patterns, we hypothesize that blow fly species abundances differ in a gradient of native vegetation cover. This study was conducted in 17 fragments across different landscapes in central Brazil. Different land cover type proportions were used to represent landscape structure. In total, 2334 specimens of nine species of Calliphoridae were collected. We used principal component analysis (PCA) to reduce dimensionality and multicollinearity of the landscape data. The first component explained 70%, and it represented a gradient of forest-pasture land uses. Alien species showed a wide distribution in different fragments with no clear relationship between the abundance values and the scores of PCA axes, whereas native species occurred only in areas with a predominance of forest cover. Our study revealed that certain native species may be sensitive to forest loss at the landscape scale, and they represent a bioindicator in forensic entomology. © 2015 American Academy of Forensic Sciences.

Voices from the street: exploring the realities of family homelessness.

PubMed

Gültekin, Laura; Brush, Barbara L; Baiardi, Janet M; Kirk, Keri; VanMaldeghem, Kelley

2014-11-01

Homelessness threatens the health and well-being of thousands of families in the United States, yet little is known about their specific needs and how current services address them. To fill this knowledge gap, we explored the experiences of homelessness families in Detroit, Michigan. We targeted homeless mothers and their caseworkers for study to see if the perceptions of needs and services were in alignment. Using focus groups and content analysis, we identified four overarching themes that illustrate homeless mothers' experience with homelessness. We then analyzed data from caseworkers to look specifically for similarities and differences in their perceptions. Key findings included reports of family histories of violence, poverty, social isolation, and a lack of informal support as contributing to homelessness. The differing perspectives of mothers and their caseworkers regarding how best to move forward highlight how current programs and services may not be meeting the needs of this growing and vulnerable cohort. © The Author(s) 2014.

Under What Conditions Does Caseworker-Caregiver Racial/Ethnic Similarity Matter for Housing Service Provision? An Application of Representative Bureaucracy Theory

PubMed Central

McBeath, Bowen; Chuang, Emmeline; Bunger, Alicia; Blakeslee, Jennifer

2014-01-01

In this article, we examine child welfare caseworkers’ housing-related service strategies when they serve culturally similar versus culturally dissimilar clients. Testing hypotheses drawn from representative bureaucracy theory and using data from the second cohort of the National Survey of Child and Adolescent Well-Being, we find that when non-Caucasian caseworkers share the same racial/ethnic background as caregivers, caseworkers use more active strategies to connect caregivers to needed housing services. The relationship between racial/ethnic matching and frontline workers’ repertoire of service strategies is most pronounced when the need for housing has been registered formally via referrals and case plans and thus legitimated institutionally. These results reinforce basic tenets of representative bureaucracy theory and provide evidence of the benefits of racial and ethnic diversity in the human service workforce. Our findings also highlight the need for research identifying institutional and frontline organizational factors that enhance the quality of service provision. PMID:25745270

Application of HLA-DRB1 genotyping by oligonucleotide micro-array technology in forensic medicine.

PubMed

Jiang, Bin; Li, Yao; Wu, Hai; He, Xianmin; Li, Chengtao; Li, Li; Tang, Rong; Xie, Yi; Mao, Yumin

2006-10-16

The human leukocyte antigen (HLA) system is known to be the most complex polymorphic system in the human genome. Among all of the HLA loci, HLA-DRB1 has the second largest number of alleles. The purpose of this study is to develop an oligonucleotide micro-array based HLA-DRB1 typing system for use in forensic identification, anthropology, tissue transplantation, and other genetic research fields. The system was developed by analyzing the HLA-DRB1 (DRB1) genotypes in 1198 unrelated healthy Chinese Han individuals originating from various parts of China and residing in Shanghai, China. Polymerase chain reaction (PCR) coupled with the oligonucleotide micro-array technology was used to detect and type HLA-DRB1 alleles of the sample individuals. The reliability, sensitivity, consistency and specificity were evaluated for use in forensic identification. Furthermore, a meta-analysis was carried out by comparing the allele frequencies of the HLA-DRB1 locus with those of other Chinese Han groups, Chinese minorities and other ethnic populations. All the DNA samples yielded a 273 bp amplification product, with no other amplification products in this length range. The minimum quantity of DNA detected by this method is 15 ng in a PCR reaction system of 25 microl. The population studied appeared to be not in Hardy-Weinberg equilibrium. Observed heterozygosity (Ho), expected heterozygosity (He), expected probability of exclusion (PE), polymorphic information content (PIC), and discrimination power (DP) of the HLA-DRB1 locus from the Shanghai Han ethnic group were evaluated to be 0.8022, 0.8870, 0.7741, 0.8771, 0.9750, respectively. A total of 25 HLA-DRB1 alleles were identified. HLA-DRB1*09XX, *04XX, *12XX and *15XX were the most frequent DRB1 alleles, which were observed in 58.76% of the sample. One hundred and sixteen genotypes were found. The five most frequent genotypes were: *04XX/*04XX (0.0626), *09XX/*09XX (0.0593), *04XX/*09XX (0.0551), *09XX/*15XX (0.0384) and *08XX/*12XX (0.0351). The meta-analysis showed that there were uniquely distributed features of DRB1 alleles among various ethnic populations and among the studied population groups from various regions with the same ethnic origin. An HLA-DRB1 genotyping system has been developed and established based on the oligonucleotide micro-array technology. The HLA-DRB1 typing of the Han population in Shanghai has revealed a relatively high heterogeneity. Information obtained in this study will be useful for medical and forensic applications as well as in anthropology research. Large-scale micro-array detection is highly accurate and reliable for DNA-based HLA-DRB1 genotyping. These results suggest that HLA-DRB1 DNA polymorphisms and the database of the Shanghai Han group have useful applications in processing forensic casework (as personal identification, paternity test), tracing population migration and genetic diagnosis.

Maltreatment type and behaviors: does listening matter?

PubMed

Merritt, Darcey H; Snyder, Susan M

2014-12-01

This article presents an exploratory assessment of whether children's perceptions of caseworker support (e.g. feeling listened to) moderates the relationship between the type of maltreatment and problematic behaviors. Relying on data collected for the National Survey of Child and Adolescent Well-Being (NSCAW I), this research measures how often children felt listened to by their caseworkers and the effect on the relationship between two types of maltreatment (e.g. physical abuse and neglect) and problematic child behaviors. Results indicate that whereas children reported feeling listened to most of the time, there are significant differences in the probabilities of problematic behavior scores between physically abused and neglected children according to how often they felt listened to. With the exception of those children who felt listened to all of the time, physically abused children have a higher probability of problematic behaviors than neglected children. Comparisons between the two maltreatment types indicate a greater impact of listening on physically abused children across the continuum of feeling listened to (e.g. never to all of the time), than for neglected children, except for at the highest level of listening, as results indicate a small, but significant difference indicating neglected children are more positively impacted by listening than physically abused kids. Implications for practice are that children's perceptions of support from caseworkers may influence behavioral outcomes differently according to maltreatment type. Additionally, these findings encourage the inclusion of children's perspectives regarding the relationships they have with caseworkers. Copyright © 2014. Published by Elsevier Ltd.

Simultaneous LC-MS/MS determination of JWH-210, RCS-4, ∆(9)-tetrahydrocannabinol, and their main metabolites in pig and human serum, whole blood, and urine for comparing pharmacokinetic data.

PubMed

Schaefer, Nadine; Kettner, Mattias; Laschke, Matthias W; Schlote, Julia; Peters, Benjamin; Bregel, Dietmar; Menger, Michael D; Maurer, Hans H; Ewald, Andreas H; Schmidt, Peter H

2015-05-01

A series of new synthetic cannabinoids (SC) has been consumed without any toxicological testing. For example, pharmacokinetic data have to be collected from forensic toxicological case work and/or animal studies. To develop a corresponding model for assessing such data, samples of controlled pig studies with two selected SC (JWH-210, RCS-4) and, as reference, ∆(9)-tetrahydrocannabinol (THC) should be analyzed as well as those of human cases. Therefore, a method for determination of JWH-210, RCS-4, THC, and their main metabolites in pig and human serum, whole blood, and urine samples is presented. Specimens were analyzed by liquid-chromatography tandem mass spectrometry and multiple-reaction monitoring with three transitions per compound. Full validation was carried out for the pig specimens and cross-validation for the human specimens concerning precision and bias. For the pig studies, the limits of detection were between 0.05 and 0.50 ng/mL in serum and whole blood and between 0.05 and 1.0 ng/mL in urine, the lower limits of quantification between 0.25 and 1.0 ng/mL in serum and 0.50 and 2.0 ng/mL in whole blood and urine, and the intra- and interday precision values lower than 15% and bias values within ±15%. The applicability was tested with samples taken from a pharmacokinetic pilot study with pigs following intravenous administration of a mixture of 200 μg/kg body mass dose each of JWH-210, RCS-4, and THC. The cross-validation data for human serum, whole blood, and urine showed that this approach should also be suitable for human specimens, e.g., of clinical or forensic cases.

Performance of the ForenSeqTM DNA Signature Prep kit on highly degraded samples.

PubMed

Fattorini, Paolo; Previderé, Carlo; Carboni, Ilaria; Marrubini, Giorgio; Sorçaburu-Cigliero, Solange; Grignani, Pierangela; Bertoglio, Barbara; Vatta, Paolo; Ricci, Ugo

2017-04-01

Next generation sequencing (NGS) is the emerging technology in forensic genomics laboratories. It offers higher resolution to address most problems of human identification, greater efficiency and potential ability to interrogate very challenging forensic casework samples. In this study, a trial set of DNA samples was artificially degraded by progressive aqueous hydrolysis, and analyzed together with the corresponding unmodified DNA sample and control sample 2800 M, to test the performance and reliability of the ForenSeq TM DNA Signature Prep kit using the MiSeq Sequencer (Illumina). The results of replicate tests performed on the unmodified sample (1.0 ng) and on scalar dilutions (1.0, 0.5 and 0.1 ng) of the reference sample 2800 M showed the robustness and the reliability of the NGS approach even from sub-optimal amounts of high quality DNA. The degraded samples showed a very limited number of reads/sample, from 2.9-10.2 folds lower than the ones reported for the less concentrated 2800 M DNA dilution (0.1 ng). In addition, it was impossible to assign up to 78.2% of the genotypes in the degraded samples as the software identified the corresponding loci as "low coverage" (< 50x). Amplification artifacts such as allelic imbalances, allele drop outs and a single allele drop in were also scored in the degraded samples. However, the ForenSeq TM DNA Sequencing kit, on the Illumina MiSeq, was able to generate data which led to the correct typing of 5.1-44.8% and 10.9-58.7% of 58 of the STRs and 92 SNPs, respectively. In all trial samples, the SNP markers showed higher chances to be typed correctly compared to the STRs. This NGS approach showed very promising results in terms of ability to recover genetic information from heavily degraded DNA samples for which the conventional PCR/CE approach gave no results. The frequency of genetic mistyping was very low, reaching the value of 1.4% for only one of the degraded samples. However, these results suggest that further validation studies and a definition of interpretation criteria for NGS data are needed before implementation of this technique in forensic genetics. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Forensic Entomology in Animal Cruelty Cases.

PubMed

Brundage, A; Byrd, J H

2016-09-01

Forensic entomology can be useful to the veterinary professional in cases of animal cruelty. A main application of forensic entomology is to determine the minimum postmortem interval by estimating the time of insect colonization, based on knowledge of the rate of development of pioneer colonizers and on insect species succession during decomposition of animal remains. Since insect development is temperature dependent, these estimates require documentation of the environmental conditions, including ambient temperature. It can also aid in the detection and recognition of wounds, as well as estimate the timing of periods of neglect. Knowledge of the geographic distribution of insects that colonize animal remains may suggest that there has been movement or concealment of the carcass or can create associations between a suspect, a victim, and a crime scene. In some instances, it can aid in the detection of drugs or toxins within decomposed or skeletonized remains. During animal cruelty investigations, it may become the responsibility of the veterinary professional to document and collect entomological evidence from live animals or during the necropsy. The applications of forensic entomology are discussed. A protocol is described for documenting and collecting entomological evidence at the scene and during the necropsy, with additional emphasis on recording geographic location, meteorological data, and collection and preservation of insect specimens. © The Author(s) 2016.

Using DNA-barcoding to make the necrobiont beetle family Cholevidae accessible for forensic entomology.

PubMed

Schilthuizen, Menno; Scholte, Cindy; van Wijk, Renske E J; Dommershuijzen, Jessy; van der Horst, Devi; Zu Schlochtern, Melanie Meijer; Lievers, Rik; Groenenberg, Dick S J

2011-07-15

The beetle family Cholevidae (Coleoptera: Staphylinoidea), sometimes viewed as the subfamily Cholevinae of the Leiodidae, consists of some 1700 species worldwide. With the exception of specialized cave-dwelling species and species living in bird and mammal nests and burrows, the species are generalized soil-dwellers that, at least in temperate regions, are mostly found on vertebrate cadavers. Although they have been regularly reported from human corpses, and offer potential because of many species' peak activity in the cold season, they have not been a focus of forensic entomologists so far. This is probably due to their small size and the difficulty in identifying the adults and their larvae. In this paper, we show that DNA-barcoding can help make this group of necrobiont beetles available as a tool for forensic research. We collected 86 specimens of 20 species of the genera Catops, Fissocatops, Apocatops, Choleva, Nargus, Ptomaphagus, and Sciodrepoides from the Netherlands and France and show that a broad "barcoding gap" allows almost all species to be easily and unambiguously identified by the sequence of the "barcoding gene" cytochrome c oxidase I (COI). This opens up the possibility of adding Cholevidae to the set of insect taxa routinely used in forensic entomology. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

Lucilia silvarum Meigen, 1826 (Diptera: Calliphoridae)--a new species of interest for forensic entomology in Europe.

PubMed

Fremdt, Heike; Szpila, Krzysztof; Huijbregts, Johannes; Lindström, Anders; Zehner, Richard; Amendt, Jens

2012-10-10

In Europe, the blowfly genus Lucilia is represented in Forensic Entomology mainly by the species L. ampullacea, L. caesar, L. illustris and L. sericata. In the US, Lucilia silvarum is rarely recorded as a carrion breeding species but usually as a more or less exclusive parasite of frogs and toads. We present three forensic cases from different European countries reporting, for the first time, L. silvarum on human bodies that were found close to lakes, wetlands, or riversides. To use this species for post-mortem interval estimations, thermal development data is needed. The first step is accurate identification by morphological and molecular means. Therefore, we analysed a 611 bp part of the mitochondrial COI region for 23 specimens of L. silvarum from 9 different geographical regions, all of which give the same haplotype. Differences within the haplotype varied by up to 0.2%. Comparison between the haplotype found and those published on GenBank showed up to 1.2% variance. Moreover, we present an updated key for the morphological identification of the third larval instars of European Lucilia spp. of forensic importance, adding not only L. silvarum, but also L. cuprina which was recorded in Europe for the first time about 20 years ago. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

Evaluation of the on-site immunoassay drug-screening device Triage-TOX in routine forensic autopsy.

PubMed

Tominaga, Mariko; Michiue, Tomomi; Maeda, Hitoshi

2015-11-01

Instrumental identification of drugs with quantification is essential in forensic toxicology, while on-site immunoassay urinalysis drug-screening devices conveniently provide preliminary information when adequately used. However, suitable or sufficient urine specimens are not always available. The present study evaluated the efficacy of a new on-site immunoassay drug-screening device Triage-TOX (Alere Inc., San Diego, CA, USA), which has recently been developed to provide objective data on the one-step automated processor, using 51 urine and 19 pericardial fluid samples from 66 forensic autopsy cases, compared with Triage-Drug of Abuse (DOA) and Monitect-9. For benzodiazepines, the positive predictive value and specificity of Triage-TOX were higher than those of Triage-DOA; however, sensitivity was higher with Monitect-9, despite frequent false-positives. The results for the other drugs with the three devices also included a few false-negatives and false-positives. These observations indicate the applicability of Triage-TOX in preliminary drug screening using urine or alternative materials in routine forensic autopsy, when a possible false-negative is considered, especially for benzodiazepines, providing objective information; however, the combined use of another device such as Monitect-9 can help minimize misinterpretation prior to instrumental analysis. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Probing the Potential of Neutron Imaging for Biomedical and Biological Applications

NASA Astrophysics Data System (ADS)

Watkin, K. L.; Bilheux, H. Z.; Ankner, J. F.

Neutron imaging of biological specimens began soon after the discovery of the neutron by Chadwick in 1932. The first samples included tumors in tissues, internal organs in rats, and bones. These studies mainly employed thermal neutrons and were often compared with X-ray images of the same or equivalent samples. Although neutron scattering is widely used in biological studies, neutron imaging has yet to be exploited to its full capability in this area. This chapter summarizes past and current research efforts to apply neutron radiography to the study of biological specimens, in the expectation that clinical and medical research, as well as forensic science, may benefit from it.

Molecular Auditing: An Evaluation of Unsuspected Tissue Specimen Misidentification.

PubMed

Demetrick, Douglas J

2018-06-18

Context Specimen misidentification is the most significant error in laboratory medicine, potentially accounting for hundreds of millions of dollars in extra health care expenses and significant morbidity in patient populations in the United States alone. New technology allows the unequivocal documentation of specimen misidentification or contamination; however, the value of this technology currently depends on suspicion of the specimen integrity by a pathologist or other health care worker. Objective To test the hypothesis that there is a detectable incidence of unsuspected tissue specimen misidentification among cases submitted for routine surgical pathology examination. Design To test this hypothesis, we selected specimen pairs that were obtained at different times and/or different hospitals from the same patient, and compared their genotypes using standardized microsatellite markers used commonly for forensic human DNA comparison in order to identify unsuspected mismatches between the specimen pairs as a trial of "molecular auditing." We preferentially selected gastrointestinal, prostate, and skin biopsies because we estimated that these types of specimens had the greatest potential for misidentification. Results Of 972 specimen pairs, 1 showed an unexpected discordant genotype profile, indicating that 1 of the 2 specimens was misidentified. To date, we are unable to identify the etiology of the discordance. Conclusions These results demonstrate that, indeed, there is a low level of unsuspected tissue specimen misidentification, even in an environment with careful adherence to stringent quality assurance practices. This study demonstrates that molecular auditing of random, routine biopsy specimens can identify occult misidentified specimens, and may function as a useful quality indicator.

Influence of pellet seating on the external ballistic parameters of spring-piston air guns.

PubMed

Werner, Ronald; Schultz, Benno; Frank, Matthias

2016-09-01

In firearm examiners' and forensic specialists' casework as well as in air gun proof testing, reliable measurement of the weapon's muzzle velocity is indispensable. While there are standardized and generally accepted procedures for testing the performance of air guns, the method of seating the diabolo pellets deeper into the breech of break barrel spring-piston air guns has not found its way into standardized test procedures. The influence of pellet seating on the external ballistic parameters was investigated using ten different break barrel spring-piston air guns. Test shots were performed with the diabolo pellets seated 2 mm deeper into the breech using a pellet seater. The results were then compared to reference shots with conventionally loaded diabolo pellets. Projectile velocity was measured with a high-precision redundant ballistic speed measurement system. In eight out of ten weapons, the muzzle energy increased significantly when the pellet seater was used. The average increase in kinetic energy was 31 % (range 9-96 %). To conclude, seating the pellet even slightly deeper into the breech of spring-piston air guns might significantly alter the muzzle energy. Therefore, it is strongly recommended that this effect is taken into account when accurate and reliable measurements of air gun muzzle velocity are necessary.

Direct qPCR quantification using the Quantifiler(®) Trio DNA quantification kit.

PubMed

Liu, Jason Yingjie

2014-11-01

The effectiveness of a direct quantification assay is essential to the adoption of the combined direct quantification/direct STR workflow. In this paper, the feasibility of using the Quantifiler(®) Trio DNA quantification kit for the direct quantification of forensic casework samples was investigated. Both low-level touch DNA samples and blood samples were collected on PE swabs and quantified directly. The increased sensitivity of the Quantifiler(®) Trio kit enabled the detection of less than 10pg of DNA in unprocessed touch samples and also minimizes the stochastic effect experienced by different targets in the same sample. The DNA quantity information obtained from a direct quantification assay using the Quantifiler(®) Trio kit can also be used to accurately estimate the optimal input DNA quantity for a direct STR amplification reaction. The correlation between the direct quantification results (Quantifiler(®) Trio kit) and the direct STR results (GlobalFiler™ PCR amplification kit(*)) for low-level touch DNA samples indicates that direct quantification using the Quantifiler(®) Trio DNA quantification kit is more reliable than the Quantifiler(®) Duo DNA quantification kit for predicting the STR results of unprocessed touch DNA samples containing less than 10pg of DNA. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

Pharmacokinetics of reduced iso-α-acids in volunteers following clear bottled beer consumption.

PubMed

Rodda, Luke N; Gerostamoulos, Dimitri; Drummer, Olaf H

2015-05-01

Reduced iso-α-acids (reduced IAA) consisting of the rho-, tetrahydro- and hexahydro-IAA groups (RIAA, TIAA and HIAA, respectively) are ingredient congeners specific to beer and generally found in clear and also occasionally green bottled beer. Concentrations of reduced IAA were determined in the blood and urine of five volunteers over 6h following the consumption of small volumes of beer containing each of the reduced IAA. The reduced IAA were absorbed and bioavailable with peak concentrations at 0.5h followed by a drop of generally fivefold by 2h. Preliminary pharmacokinetics of these compounds in humans shows relatively small inter-individual differences and an estimated short half-life varying between ∼38 and 46min for the three groups. Comparison of RIAA analyte ratios within the group indicate that some analytes eliminate relatively faster than others and the formation of metabolite products was observed. Preliminary urine analysis showed only unmodified RIAA analytes were detectable throughout 6h and suggests extensive phase I metabolism of TIAA and HIAA analytes. In authentic forensic casework where clear or green bottled beers are consumed, the identification of reduced IAA groups may provide a novel method to target ingredient congeners consistent with beer ingestion and suggest the type of beer consumed. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Electrostatic sampling of trace DNA from clothing.

PubMed

Zieger, Martin; Defaux, Priscille Merciani; Utz, Silvia

2016-05-01

During acts of physical aggression, offenders frequently come into contact with clothes of the victim, thereby leaving traces of DNA-bearing biological material on the garments. Since tape-lifting and swabbing, the currently established methods for non-destructive trace DNA sampling from clothing, both have their shortcomings in collection efficiency and handling, we thought about a new collection method for these challenging samples. Testing two readily available electrostatic devices for their potential to sample biological material from garments made of different fabrics, we found one of them, the electrostatic dust print lifter (DPL), to perform comparable to well-established sampling with wet cotton swabs. In simulated aggression scenarios, we had the same success rate for the establishment of single aggressor profiles, suitable for database submission, with both the DPL and wet swabbing. However, we lost a substantial amount of information with electrostatic sampling, since almost no mixed aggressor-victim profiles suitable for database entry could be established, compared to conventional swabbing. This study serves as a proof of principle for electrostatic DNA sampling from items of clothing. The technique still requires optimization before it might be used in real casework. But we are confident that in the future it could be an efficient and convenient contribution to the toolbox of forensic practitioners.

Library Search Prefilters for Vehicle Manufacturers to Assist in the Forensic Examination of Automotive Paints.

PubMed

Lavine, Barry K; White, Collin G; Ding, Tao

2018-03-01

Pattern recognition techniques have been applied to the infrared (IR) spectral libraries of the Paint Data Query (PDQ) database to differentiate between nonidentical but similar IR spectra of automotive paints. To tackle the problem of library searching, search prefilters were developed to identify the vehicle make from IR spectra of the clear coat, surfacer-primer, and e-coat layers. To develop these search prefilters with the appropriate degree of accuracy, IR spectra from the PDQ database were preprocessed using the discrete wavelet transform to enhance subtle but significant features in the IR spectral data. Wavelet coefficients characteristic of vehicle make were identified using a genetic algorithm for pattern recognition and feature selection. Search prefilters to identify automotive manufacturer through IR spectra obtained from a paint chip recovered at a crime scene were developed using 1596 original manufacturer's paint systems spanning six makes (General Motors, Chrysler, Ford, Honda, Nissan, and Toyota) within a limited production year range (2000-2006). Search prefilters for vehicle manufacturer that were developed as part of this study were successfully validated using IR spectra obtained directly from the PDQ database. Information obtained from these search prefilters can serve to quantify the discrimination power of original automotive paint encountered in casework and further efforts to succinctly communicate trace evidential significance to the courts.

Raman spectroscopy for forensic examination of β-ketophenethylamine "legal highs": reference and seized samples of cathinone derivatives.

PubMed

Stewart, Samantha P; Bell, Steven E J; Fletcher, Nicholas C; Bouazzaoui, Samira; Ho, Yen Cheng; Speers, S James; Peters, K Laota

2012-01-20

Raman spectra of a representative range of β-ketophenethylamine (β-KP), the rapidly growing family of cathinone-related "legal high" recreational drugs, have been recorded. These spectra showed characteristic changes that were associated with the pattern of substitution on the aromatic rings, for example, the compounds carrying substituents at the 4- position could be distinguished from 3,4-methylenedioxy "ecstasy" derivatives. They also showed small but detectable changes with differences in substitution on the ethylamine substituent. These features allowed the β-KPs present in seized casework samples to be identified. The seized samples typically contained only small amounts of bulking agents, which meant that the band intensities of these components within averaged data were very small. In contrast, grid sampling normally gave at least some spectra which had a higher than average proportion of the bulking agent(s), which allowed them to also be identified. This study therefore demonstrates that Raman spectroscopy can be used both to provide a rapid, non-destructive technique for identification of this class of drugs in seized samples and to detect minor constituents, giving a composition profile which can be used for drugs intelligence work. Crown Copyright © 2011. Published by Elsevier B.V. All rights reserved.

Proteomic analysis of hair shafts from monozygotic twins: Expression profiles and genetically variant peptides.

PubMed

Wu, Pei-Wen; Mason, Katelyn E; Durbin-Johnson, Blythe P; Salemi, Michelle; Phinney, Brett S; Rocke, David M; Parker, Glendon J; Rice, Robert H

2017-07-01

Forensic association of hair shaft evidence with individuals is currently assessed by comparing mitochondrial DNA haplotypes of reference and casework samples, primarily for exclusionary purposes. Present work tests and validates more recent proteomic approaches to extract quantitative transcriptional and genetic information from hair samples of monozygotic twin pairs, which would be predicted to partition away from unrelated individuals if the datasets contain identifying information. Protein expression profiles and polymorphic, genetically variant hair peptides were generated from ten pairs of monozygotic twins. Profiling using the protein tryptic digests revealed that samples from identical twins had typically an order of magnitude fewer protein expression differences than unrelated individuals. The data did not indicate that the degree of difference within twin pairs increased with age. In parallel, data from the digests were used to detect genetically variant peptides that result from common nonsynonymous single nucleotide polymorphisms in genes expressed in the hair follicle. Compilation of the variants permitted sorting of the samples by hierarchical clustering, permitting accurate matching of twin pairs. The results demonstrate that genetic differences are detectable by proteomic methods and provide a framework for developing quantitative statistical estimates of personal identification that increase the value of hair shaft evidence. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Insects and associated arthropods analyzed during medicolegal death investigations in Harris County, Texas, USA: January 2013- April 2016

PubMed Central

2017-01-01

The application of insect and arthropod information to medicolegal death investigations is one of the more exacting applications of entomology. Historically limited to homicide investigations, the integration of full time forensic entomology services to the medical examiner’s office in Harris County has opened up the opportunity to apply entomology to a wide variety of manner of death classifications and types of scenes to make observations on a number of different geographical and species-level trends in Harris County, Texas, USA. In this study, a retrospective analysis was made of 203 forensic entomology cases analyzed during the course of medicolegal death investigations performed by the Harris County Institute of Forensic Sciences in Houston, TX, USA from January 2013 through April 2016. These cases included all manner of death classifications, stages of decomposition and a variety of different scene types that were classified into decedents transported from the hospital (typically associated with myiasis or sting allergy; 3.0%), outdoor scenes (32.0%) or indoor scenes (65.0%). Ambient scene air temperature at the time scene investigation was the only significantly different factor observed between indoor and outdoor scenes with average indoor scene temperature being slightly cooler (25.2°C) than that observed outdoors (28.0°C). Relative humidity was not found to be significantly different between scene types. Most of the indoor scenes were classified as natural (43.3%) whereas most of the outdoor scenes were classified as homicides (12.3%). All other manner of death classifications came from both indoor and outdoor scenes. Several species were found to be significantly associated with indoor scenes as indicated by a binomial test, including Blaesoxipha plinthopyga (Wiedemann) (Diptera: Sarcophagidae), all Sarcophagidae (including B. plinthopyga), Megaselia scalaris Loew (Diptera: Phoridae), Synthesiomyia nudiseta Wulp (Diptera: Muscidae) and Lucilia cuprina (Wiedemann) (Diptera: Calliphoridae). The only species that was a significant indicator of an outdoor scene was Lucilia eximia (Wiedemann) (Diptera: Calliphoridae). All other insect species that were collected in five or more cases were collected from both indoor and outdoor scenes. A species list with month of collection and basic scene characteristics with the length of the estimated time of colonization is also presented. The data presented here provide valuable casework related species data for Harris County, TX and nearby areas on the Gulf Coast that can be used to compare to other climate regions with other species assemblages and to assist in identifying new species introductions to the area. This study also highlights the importance of potential sources of uncertainty in preparation and interpretation of forensic entomology reports from different scene types. PMID:28604832

Insects and associated arthropods analyzed during medicolegal death investigations in Harris County, Texas, USA: January 2013- April 2016.

PubMed

Sanford, Michelle R

2017-01-01

The application of insect and arthropod information to medicolegal death investigations is one of the more exacting applications of entomology. Historically limited to homicide investigations, the integration of full time forensic entomology services to the medical examiner's office in Harris County has opened up the opportunity to apply entomology to a wide variety of manner of death classifications and types of scenes to make observations on a number of different geographical and species-level trends in Harris County, Texas, USA. In this study, a retrospective analysis was made of 203 forensic entomology cases analyzed during the course of medicolegal death investigations performed by the Harris County Institute of Forensic Sciences in Houston, TX, USA from January 2013 through April 2016. These cases included all manner of death classifications, stages of decomposition and a variety of different scene types that were classified into decedents transported from the hospital (typically associated with myiasis or sting allergy; 3.0%), outdoor scenes (32.0%) or indoor scenes (65.0%). Ambient scene air temperature at the time scene investigation was the only significantly different factor observed between indoor and outdoor scenes with average indoor scene temperature being slightly cooler (25.2°C) than that observed outdoors (28.0°C). Relative humidity was not found to be significantly different between scene types. Most of the indoor scenes were classified as natural (43.3%) whereas most of the outdoor scenes were classified as homicides (12.3%). All other manner of death classifications came from both indoor and outdoor scenes. Several species were found to be significantly associated with indoor scenes as indicated by a binomial test, including Blaesoxipha plinthopyga (Wiedemann) (Diptera: Sarcophagidae), all Sarcophagidae (including B. plinthopyga), Megaselia scalaris Loew (Diptera: Phoridae), Synthesiomyia nudiseta Wulp (Diptera: Muscidae) and Lucilia cuprina (Wiedemann) (Diptera: Calliphoridae). The only species that was a significant indicator of an outdoor scene was Lucilia eximia (Wiedemann) (Diptera: Calliphoridae). All other insect species that were collected in five or more cases were collected from both indoor and outdoor scenes. A species list with month of collection and basic scene characteristics with the length of the estimated time of colonization is also presented. The data presented here provide valuable casework related species data for Harris County, TX and nearby areas on the Gulf Coast that can be used to compare to other climate regions with other species assemblages and to assist in identifying new species introductions to the area. This study also highlights the importance of potential sources of uncertainty in preparation and interpretation of forensic entomology reports from different scene types.

FDSTools: A software package for analysis of massively parallel sequencing data with the ability to recognise and correct STR stutter and other PCR or sequencing noise.

PubMed

Hoogenboom, Jerry; van der Gaag, Kristiaan J; de Leeuw, Rick H; Sijen, Titia; de Knijff, Peter; Laros, Jeroen F J

2017-03-01

Massively parallel sequencing (MPS) is on the advent of a broad scale application in forensic research and casework. The improved capabilities to analyse evidentiary traces representing unbalanced mixtures is often mentioned as one of the major advantages of this technique. However, most of the available software packages that analyse forensic short tandem repeat (STR) sequencing data are not well suited for high throughput analysis of such mixed traces. The largest challenge is the presence of stutter artefacts in STR amplifications, which are not readily discerned from minor contributions. FDSTools is an open-source software solution developed for this purpose. The level of stutter formation is influenced by various aspects of the sequence, such as the length of the longest uninterrupted stretch occurring in an STR. When MPS is used, STRs are evaluated as sequence variants that each have particular stutter characteristics which can be precisely determined. FDSTools uses a database of reference samples to determine stutter and other systemic PCR or sequencing artefacts for each individual allele. In addition, stutter models are created for each repeating element in order to predict stutter artefacts for alleles that are not included in the reference set. This information is subsequently used to recognise and compensate for the noise in a sequence profile. The result is a better representation of the true composition of a sample. Using Promega Powerseq™ Auto System data from 450 reference samples and 31 two-person mixtures, we show that the FDSTools correction module decreases stutter ratios above 20% to below 3%. Consequently, much lower levels of contributions in the mixed traces are detected. FDSTools contains modules to visualise the data in an interactive format allowing users to filter data with their own preferred thresholds. Copyright © 2016 The Authors. Published by Elsevier B.V. All rights reserved.

Mortuary operations in the aftermath of the 2009 Victorian bushfires.

PubMed

Leditschke, Jodie; Collett, Sarsha; Ellen, Rebecca

2011-02-25

On the day of the 2009 Victorian bushfires the Victorian Institute of Forensic Medicine activated its emergency plan. Within 48 h a temporary body storage facility was constructed adjacent to the existing mortuary. This temporary facility had the capacity to store up to 300 deceased persons. Pathologists, anthropologists, odontologists, police and mortuary assistants responded from all around Australia, New Zealand and Indonesia. The existing forensic mortuary and staff were divided into two areas: DVI (disaster victim identification) and "routine operations". A high priority for the mortuary was to ensure the casework of the "routine" deceased persons (those cases which were not related to the bushfires) was handled concurrently and in a timely manner. On admission each set of victim remains was given both a Coroner's case number in addition to the DVI number allocated at the scene. The case was CT scanned, examined by a pathologist, an anthropologist, and odontologist and in some instances a fingerprint expert. Where possible a DNA sample was taken. All processes, samples, labels and paperwork underwent a quality assurance check prior to the case completion. Regular audits were conducted. All of post mortem examinations were completed within 20 days of admission. Occupational health and safety issues of the staff were a high priority; this included correct manual handling, infection control and psychological debriefings. During the operation it was found that some remains were contaminated with asbestos. Procedures were set in place to manage these cases individually and each was isolated to reduce the risk of exposure by staff to asbestos. This overall mortuary operation identified a number of significant challenges, in particular the management of multiple parts of human remains for one individual. A new procedure was developed to ensure that all human remains, where possible, were reconciled with identified deceased persons prior to the release to the funeral director. It also highlighted the need to have well documented plans in place including plans for temporary mortuary facilities. Copyright © 2010 Elsevier Ireland Ltd. All rights reserved.

Bona fide colour: DNA prediction of human eye and hair colour from ancient and contemporary skeletal remains

PubMed Central

2013-01-01

Background DNA analysis of ancient skeletal remains is invaluable in evolutionary biology for exploring the history of species, including humans. Contemporary human bones and teeth, however, are relevant in forensic DNA analyses that deal with the identification of perpetrators, missing persons, disaster victims or family relationships. They may also provide useful information towards unravelling controversies that surround famous historical individuals. Retrieving information about a deceased person’s externally visible characteristics can be informative in both types of DNA analyses. Recently, we demonstrated that human eye and hair colour can be reliably predicted from DNA using the HIrisPlex system. Here we test the feasibility of the novel HIrisPlex system at establishing eye and hair colour of deceased individuals from skeletal remains of various post-mortem time ranges and storage conditions. Methods Twenty-one teeth between 1 and approximately 800 years of age and 5 contemporary bones were subjected to DNA extraction using standard organic protocol followed by analysis using the HIrisPlex system. Results Twenty-three out of 26 bone DNA extracts yielded the full 24 SNP HIrisPlex profile, therefore successfully allowing model-based eye and hair colour prediction. HIrisPlex analysis of a tooth from the Polish general Władysław Sikorski (1881 to 1943) revealed blue eye colour and blond hair colour, which was positively verified from reliable documentation. The partial profiles collected in the remaining three cases (two contemporary samples and a 14th century sample) were sufficient for eye colour prediction. Conclusions Overall, we demonstrate that the HIrisPlex system is suitable, sufficiently sensitive and robust to successfully predict eye and hair colour from ancient and contemporary skeletal remains. Our findings, therefore, highlight the HIrisPlex system as a promising tool in future routine forensic casework involving skeletal remains, including ancient DNA studies, for the prediction of eye and hair colour of deceased individuals. PMID:23317428

Bona fide colour: DNA prediction of human eye and hair colour from ancient and contemporary skeletal remains.

PubMed

Draus-Barini, Jolanta; Walsh, Susan; Pośpiech, Ewelina; Kupiec, Tomasz; Głąb, Henryk; Branicki, Wojciech; Kayser, Manfred

2013-01-14

DNA analysis of ancient skeletal remains is invaluable in evolutionary biology for exploring the history of species, including humans. Contemporary human bones and teeth, however, are relevant in forensic DNA analyses that deal with the identification of perpetrators, missing persons, disaster victims or family relationships. They may also provide useful information towards unravelling controversies that surround famous historical individuals. Retrieving information about a deceased person's externally visible characteristics can be informative in both types of DNA analyses. Recently, we demonstrated that human eye and hair colour can be reliably predicted from DNA using the HIrisPlex system. Here we test the feasibility of the novel HIrisPlex system at establishing eye and hair colour of deceased individuals from skeletal remains of various post-mortem time ranges and storage conditions. Twenty-one teeth between 1 and approximately 800 years of age and 5 contemporary bones were subjected to DNA extraction using standard organic protocol followed by analysis using the HIrisPlex system. Twenty-three out of 26 bone DNA extracts yielded the full 24 SNP HIrisPlex profile, therefore successfully allowing model-based eye and hair colour prediction. HIrisPlex analysis of a tooth from the Polish general Władysław Sikorski (1881 to 1943) revealed blue eye colour and blond hair colour, which was positively verified from reliable documentation. The partial profiles collected in the remaining three cases (two contemporary samples and a 14th century sample) were sufficient for eye colour prediction. Overall, we demonstrate that the HIrisPlex system is suitable, sufficiently sensitive and robust to successfully predict eye and hair colour from ancient and contemporary skeletal remains. Our findings, therefore, highlight the HIrisPlex system as a promising tool in future routine forensic casework involving skeletal remains, including ancient DNA studies, for the prediction of eye and hair colour of deceased individuals.

The Distribution of Fluoxetine and Norfluoxetine in Postmortem Fluids and Tissues

DTIC Science & Technology

2007-06-01

of fluoxetine and nor- fluoxetine in dogs following oral administration of fluoxetine hydrochloride ( Prozac ). J Forensic Sci, 42(5):812-6, 1997. 6...flight crews are submitted to the Federal Aviation Administration’s Civil Aerospace Medical Institute for toxicological analysis. Fluoxetine ( Prozac ...heart muscle, and brain. Specimens were extracted using solid-phase extraction and analyzed by GC/MS. Deuterated fluoxetine and norfluoxetine were

Disposable pipette extraction for gas chromatographic determination of codeine, morphine, and 6-monoacetylmorphine in vitreous humor.

PubMed

Kovatsi, Leda; Rentifis, Konstantinos; Giannakis, Dimitrios; Njau, Samuel; Samanidou, Victoria

2011-07-01

The availability of a sensitive and rapid analytical method for the determination of opiates, and other substances of forensic interest, in a variety of biological specimens is of utmost importance to forensic laboratories. Solid-phase extraction is very popular in the pre-treatment of forensic samples. Nevertheless, a new approach, disposable pipette extraction (DPX), is gaining increasing interest in sample preparation. DPX has already been applied to the analysis of drugs of abuse in common biological matrices, such as urine and blood, but has not yet been evaluated on alternative biological samples, such as vitreous humor. The objective of this study was to evaluate the applicability of DPX on the analysis of opiates in vitreous humor. The currently developed method is fast, reliable, and easy to perform. The sensitivity, precision, and accuracy are satisfactory. Recoveries obtained are within the range of 72-91%, whereas the sample volume of vitreous humor required is only 100 μL. Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Laser mass spectrometry for DNA fingerprinting for forensic applications

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chen, C.H.; Tang, K.; Taranenko, N.I.

The application of DNA fingerprinting has become very broad in forensic analysis, patient identification, diagnostic medicine, and wildlife poaching, since every individual`s DNA structure is identical within all tissues of their body. DNA fingerprinting was initiated by the use of restriction fragment length polymorphisms (RFLP). In 1987, Nakamura et al. found that a variable number of tandem repeats (VNTR) often occurred in the alleles. The probability of different individuals having the same number of tandem repeats in several different alleles is very low. Thus, the identification of VNTR from genomic DNA became a very reliable method for identification of individuals.more » DNA fingerprinting is a reliable tool for forensic analysis. In DNA fingerprinting, knowledge of the sequence of tandem repeats and restriction endonuclease sites can provide the basis for identification. The major steps for conventional DNA fingerprinting include (1) specimen processing (2) amplification of selected DNA segments by PCR, and (3) gel electrophoresis to do the final DNA analysis. In this work we propose to use laser desorption mass spectrometry for fast DNA fingerprinting. The process and advantages are discussed.« less

Capturing and displaying microscopic images used in medical diagnostics and forensic science using 4K video resolution - an application in higher education.

PubMed

Maier, Hans; de Heer, Gert; Ortac, Ajda; Kuijten, Jan

2015-11-01

To analyze, interpret and evaluate microscopic images, used in medical diagnostics and forensic science, video images for educational purposes were made with a very high resolution of 4096 × 2160 pixels (4K), which is four times as many pixels as High-Definition Video (1920 × 1080 pixels). The unprecedented high resolution makes it possible to see details that remain invisible to any other video format. The images of the specimens (blood cells, tissue sections, hair, fibre, etc.) are recorded using a 4K video camera which is attached to a light microscope. After processing, this resulted in very sharp and highly detailed images. This material was then used in education for classroom discussion. Spoken explanation by experts in the field of medical diagnostics and forensic science was also added to the high-resolution video images to make it suitable for self-study. © 2015 The Authors. Journal of Microscopy published by John Wiley & Sons Ltd on behalf of Royal Microscopical Society.

A checklist of beetles (Insecta, Coleoptera) on pig carcasses in the suburban area of southwestern China: A preliminary study and its forensic relevance.

PubMed

Lyu, Zhou; Wan, Li-Hua; Yang, Yong-Qiang; Tang, Rui; Xu, Lyu-Zi

2016-07-01

Examining the succession pattern of carrion insects on vertebrate carcasses is widely accepted as an effective method to estimate the postmortem interval (PMI) of decayed bodies. Investigation of the community of sarcosaprophagous insects, especially flies and beetles, is the foundation of the succession pattern study. This study aimed to investigate the sarcosaprophagous beetles succession on animal carcasses in the suburban area of southwestern China and to establish a basic catalog for forensic application. The present study was conducted in 2013 in a mountain in Chongqing municipality with modified Schoenly traps. Carcasses of miniature pig were used to simulate human bodies. For most carcasses, five decomposition stages were observed. A total of 2108 adult coleopterans belonging to at least 61 species and 18 families were collected in the study, and most of the specimens occurred at the advanced decay stage. Omosita colon (Linnaeus, 1758), Necrodes nigricornis (Harold, 1875), Necrobia ruficollis (Fabricius, 1775) and Neosilusa ceylonica (Kraatz, 1857) were the dominant species. Copyright © 2016 Elsevier Ltd and Faculty of Forensic and Legal Medicine. All rights reserved.

Framework for culturally competent decisionmaking in child welfare.

PubMed

Cohen, Elena P

2003-01-01

This article provides a framework to understand the cultural, social, political, and economic factors that affect decisionmaking when working with ethnically and racially diverse families in the child welfare system. The article describes external factors affecting the decisionmaking process, including community environment, agency structure, and family characteristics. It then reviews the core stages of the casework process, describing key decisions during intake, assessment, service planning, implementation, evaluation, and closure. Although the framework is based on casework process in the child welfare system, it can be adapted to other child-serving systems, including education, mental health, and juvenile justice.

Simultaneous determination of LSD and 2-oxo-3-hydroxy LSD in hair and urine by LC-MS/MS and its application to forensic cases.

PubMed

Jang, Moonhee; Kim, Jihyun; Han, Inhoi; Yang, Wonkyung

2015-11-10

Lysergic acid diethylamide (LSD) is administered in low dosages, which makes its detection in biological matrices a major challenge in forensic toxicology. In this study, two sensitive and reliable methods based on liquid chromatography-tandem mass spectrometry (LC-MS/MS) were established and validated for the simultaneous determination of LSD and its metabolite, 2-oxo-3-hydroxy-LSD (O-H-LSD), in hair and urine. Target analytes in hair were extracted using methanol at 38°C for 15h and analyzed by LC-MS/MS. For urine sample preparation, liquid-liquid extraction was performed. Limits of detection (LODs) in hair were 0.25pg/mg for LSD and 0.5pg/mg for O-H-LSD. In urine, LODs were 0.01 and 0.025ng/ml for LSD and O-H-LSD, respectively. Method validation results showed good linearity and acceptable precision and accuracy. The developed methods were applied to authentic specimens from two legal cases of LSD ingestion, and allowed identification and quantification of LSD and O-H-LSD in the specimens. In the two cases, LSD concentrations in hair were 1.27 and 0.95pg/mg; O-H-LSD was detected in one case, but its concentration was below the limit of quantification. In urine samples collected from the two suspects 8 and 3h after ingestion, LSD concentrations were 0.48 and 2.70ng/ml, respectively, while O-H-LSD concentrations were 4.19 and 25.2ng/ml, respectively. These methods can be used for documenting LSD intake in clinical and forensic settings. Copyright © 2015 Elsevier B.V. All rights reserved.

Hymenopteran parasitoids of forensic importance: host associations, seasonality, and prevalence of parasitoids of carrion flies in Western Australia.

PubMed

Voss, Sasha C; Spafford, Helen; Dadour, Ian R

2009-09-01

A 2-yr survey of hymenopteran parasitoids associated with carrion-breeding flies was conducted to establish the parasitoid species of potential forensic significance in Western Australia. Host associations, seasonality, and rates of parasitism in the field were examined to assess the value of the identified parasitoids as forensic indicators of time since death. Four species of parasitoid emerged from dipteran specimens collected from carcasses: Tachinaephagus zealandicus Ashmead (Encryptidae), Nasonia vitripennis Walker (Pteromalidae), Spilomicrus sp. (Diapriidae), and Aphaereta sp. (Braconidae). Overall parasitism of carrion-breeding flies was 11.8%. T. zealandicus and N. vitripennis were the predominant species, accounting for 86.3 and 11.5% of parasitism observed, respectively. In contrast, Aphaereta sp. and Spilomicrus sp. were intermittently collected from carcasses throughout the study and the parasitism rates of both species were low (< or = 3.0%). Our findings provide forensically important biological and behavioral data of parasitoid-host interactions within carcass environments. The cosmopolitan parasitoids T. zealandicus and N. vitripennis have the greatest potential as indicators of time since death in forensic investigations based on their broad host ranges, rates of parasitism, and seasonal prevalence. In combination, these two species are present throughout the year and they parasitized nearly all of the dipteran species that colonize carcasses. Because both are cosmopolitan species, the data presented here are applicable to regions experiencing a similar Mediterranean climate. This work reports the first incidence of T. zealandicus and N. vitripennis parasitizing the dipteran species Calliphora albifrontalis Malloch (Calliphoridae), Calliphora dubia Macquart (Calliphoridae), and Hydrotaea rostrata Robineau-Desvoidy (Muscidae).

Assessing the Organizational Social Context (OSC) of child welfare systems: implications for research and practice.

PubMed

Glisson, Charles; Green, Philip; Williams, Nathaniel J

2012-09-01

The study: (1) provides the first assessment of the a priori measurement model and psychometric properties of the Organizational Social Context (OSC) measurement system in a US nationwide probability sample of child welfare systems; (2) illustrates the use of the OSC in constructing norm-based organizational culture and climate profiles for child welfare systems; and (3) estimates the association of child welfare system-level organizational culture and climate profiles with individual caseworker-level job satisfaction and organizational commitment. The study applies confirmatory factor analysis (CFA) and hierarchical linear models (HLM) analysis to a US nationwide sample of 1,740 caseworkers from 81 child welfare systems participating in the second National Survey of Child and Adolescent Wellbeing (NSCAW II). The participating child welfare systems were selected using a national probability procedure reflecting the number of children served by child welfare systems nationwide. The a priori OSC measurement model is confirmed in this nationwide sample of child welfare systems. In addition, caseworker responses to the OSC scales generate acceptable to high scale reliabilities, moderate to high within-system agreement, and significant between-system differences. Caseworkers in the child welfare systems with the best organizational culture and climate profiles report higher levels of job satisfaction and organizational commitment. Organizational climates characterized by high engagement and functionality, and organizational cultures characterized by low rigidity are associated with the most positive work attitudes. The OSC is the first valid and reliable measure of organizational culture and climate with US national norms for child welfare systems. The OSC provides a useful measure of Organizational Social Context for child welfare service improvement and implementation research efforts which include a focus on child welfare system culture and climate. Copyright © 2012 Elsevier Ltd. All rights reserved.

Analysis and comparison of glass fragments by laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) and ICP-MS.

PubMed

Trejos, Tatiana; Montero, Shirly; Almirall, José R

2003-08-01

The discrimination potential of Laser Ablation Inductively Coupled Plasma Mass Spectrometry (LA-ICP-MS) is compared with previously reported solution ICP-MS methods using external calibration (EC) with internal standardization and a newly reported solution isotope dilution (ID) method for the analysis of two different glass populations. A total of 91 different glass samples were used for the comparison study; refractive index and elemental composition were measured by the techniques mentioned above. One set consisted of 45 headlamps taken from a variety of automobiles that represents a range of 20 years of manufacturing dates. A second set consisted of 46 automotive glasses (side windows, rear windows, and windshields) representing casework glass from different vehicle manufacturers over several years. The element menu for the LA-ICP-MS and EC-ICP-MS methods include Mg, Al, Ca, Mn, Ce, Ti, Zr, Sb, Ga, Ba, Rb, Sm, Sr, Hf, La, and Pb. The ID method was limited to the analysis of two isotopes each of Mg, Sr, Zr, Sb, Ba, Sm, Hf, and Pb. Laser ablation analyses were performed with a Q switched Nd:YAG, 266 nm, 6 mJ output energy laser. The laser was used in depth profile mode while sampling using a 50 microm spot size for 50 sec at 10 Hz (500 shots). The typical bias for the analysis of NIST 612 by LA-ICP-MS was less than 5% in all cases and typically better than 5% for most isotopes. The precision for the vast majority of the element menu was determined generally less than 10% for all the methods when NIST 612 was measured (40 microg x g(-1)). Method detection limits (MDL) for the EC and LA-ICP-MS methods were similar and generally reported as less than 1 microg x g(-1) for the analysis of NIST 612. While the solution sample introduction methods using EC and ID presented excellent sensitivity and precision, these methods have the disadvantages of destroying the sample, and also involve complex sample preparation. The laser ablation method was simpler, faster, and produced comparable discrimination to the EC-ICP-MS and ID-ICP-MS. LA-ICP-MS can offer an excellent alternative to solution analysis of glass in forensic casework samples.

DNA decontamination of fingerprint brushes.

PubMed

Szkuta, Bianca; Oorschot, Roland A H van; Ballantyne, Kaye N

2017-08-01

Genetic profiling of DNA collected from fingerprints that have been exposed to various enhancement techniques is routine in many forensic laboratories. As a result of direct contact with fingermark residues during treatment, there is concern around the DNA contamination risk of dusting fingermarks with fingerprint brushes. Previous studies have demonstrated the potential for cross-contamination between evidentiary items through various mechanisms, highlighting the risk of using the same fingerprint brush to powder multiple surfaces within and between crime-scenes. Experiments were performed to assess the contamination risk of reused fingerprint brushes through the transfer of dried saliva and skin deposits from and to glass surfaces with new unused squirrel hair and fiberglass brushes. Additional new unused brushes and brushes previously used in casework were also tested for their ability to contaminate samples. In addition, the ability to eradicate DNA from used squirrel hair and fiberglass fingerprint brushes was assessed using a 1% sodium hypochlorite solution and a 5% solution of a commercially available alternative, Virkon. DNA profiling results from surfaces contacted by treated and untreated brushes were compared to determine the effectiveness of the devised cleaning protocol. Brush durability was also assessed over multiple wash/rinse/dry cycles with both agents. Varying amounts of DNA-containing material were collected and transferred by squirrel hair and fiberglass brushes, with detectability on the secondary surface dependent on the biological nature of the material being transferred. The impact of DNA contamination from dirty fingerprint brushes was most apparent in simulations involving the transfer of dried saliva and brushes previously used in casework, while minimal transfer of touch DNA was observed. Alarmingly, large quantities of DNA were found to reside on new unused squirrel hair brushes, while no DNA was detected on new unused fiberglass brushes or brushes sold as DNA-free. Squirrel hair brushes were easily and effectively cleaned with both hypochlorite and Virkon, with no evidence of DNA transfer between exhibits by treated brushes. Brushes were still deemed useable after multiple cleaning cycles with either agent. In contrast, fiberglass bristles became tangled and matted when wet and could not be cleaned effectively using either method. It is recommended they are disposed of following use. Each laboratory should consider their current circumstances before adapting a cleaning method. The implementation of a program to monitor the effectiveness of the cleaning regime is also advised. Copyright © 2017 Elsevier B.V. All rights reserved.

Magazine Influence on Cartridge Case Ejection Patterns with Glock Pistols.

PubMed

Kerkhoff, Wim; Alberink, Ivo; Mattijssen, Erwin J A T

2018-01-01

In this study, the cartridge case ejection patterns of six different Glock model pistols (one specimen per model) were compared under three conditions: firing with a loaded magazine, an empty magazine, and without magazine. The distances, covered by the ejected cartridge cases given these three conditions, were compared for each of the six models. A significant difference was found between the groups of data for each of the tested specimens. This indicates that it is important that, to reconstruct a shooting scene incident based on the ejection patterns of a pistol, test shots are fired with the same pistol type and under the correct magazine condition. © 2017 American Academy of Forensic Sciences.

Advances in the use of odour as forensic evidence through optimizing and standardizing instruments and canines

PubMed Central

Furton, Kenneth G.; Caraballo, Norma Iris; Cerreta, Michelle M.; Holness, Howard K.

2015-01-01

This paper explores the advances made in identifying trace amounts of volatile organic compounds (VOCs) that originate from forensic specimens, such as drugs, explosives, live human scent and the scent of death, as well as the probative value for detecting such odours. The ability to locate and identify the VOCs liberated from or left by forensic substances is of increasing importance to criminal investigations as it can indicate the presence of contraband and/or associate an individual to a particular location or object. Although instruments have improved significantly in recent decades—with sensitivities now rivalling that of biological detectors—it is widely recognized that canines are generally still more superior for the detection of odourants due to their speed, versatility, ruggedness and discriminating power. Through advancements in the detection of VOCs, as well as increased standardization efforts for instruments and canines, the reliability of odour as evidence has continuously improved and is likely to continue to do so. Moreover, several legal cases in which this novel form of evidence has been accepted into US courts of law are discussed. As the development and implementation of best practice guidelines for canines and instruments increase, their reliability in detecting VOCs of interest should continue to improve, expanding the use of odour as an acceptable form of forensic evidence. PMID:26101287

A forensic entomology case from the Amazon rain forest of Brazil.

PubMed

Pujol-Luz, José R; Marques, Helder; Ururahy-Rodrigues, Alexandre; Rafael, José Albertino; Santana, Fernando H A; Arantes, Luciano C; Constantino, Reginaldo

2006-09-01

The first case of application of forensic entomology in the Brazilian Amazonia is described. The corpses of 26 men were found in the rainforest in Rondonia State, Brazil. Fly larvae collected on the bodies during autopsy were identified as Paralucilia fulvinota (Diptera, Calliphoridae). No data or specimens were collected at the crime scene. At the laboratory, the larvae developed into pupae in 58 h and into adults in 110.5 h. The total development time for P. fulvinota was measured in field experiments inside the forest. The age of the larvae when collected from the bodies was estimated as the difference between the time required for them to become adults and the total development time for this species. The estimated age of the maggots and the minimum postmortem interval was 5.7 days.

A validated method for the quantitation of 1,1-difluoroethane using a gas in equilibrium method of calibration.

PubMed

Avella, Joseph; Lehrer, Michael; Zito, S William

2008-10-01

1,1-Difluoroethane (DFE), also known as Freon 152A, is a member of a class of compounds known as halogenated hydrocarbons. A number of these compounds have gained notoriety because of their ability to induce rapid onset of intoxication after inhalation exposure. Abuse of DFE has necessitated development of methods for its detection and quantitation in postmortem and human performance specimens. Furthermore, methodologies applicable to research studies are required as there have been limited toxicokinetic and toxicodynamic reports published on DFE. This paper describes a method for the quantitation of DFE using a gas chromatography-flame-ionization headspace technique that employs solventless standards for calibration. Two calibration curves using 0.5 mL whole blood calibrators which ranged from A: 0.225-1.350 to B: 9.0-180.0 mg/L were developed. These were evaluated for linearity (0.9992 and 0.9995), limit of detection of 0.018 mg/L, limit of quantitation of 0.099 mg/L (recovery 111.9%, CV 9.92%), and upper limit of linearity of 27,000.0 mg/L. Combined curve recovery results of a 98.0 mg/L DFE control that was prepared using an alternate technique was 102.2% with CV of 3.09%. No matrix interference was observed in DFE enriched blood, urine or brain specimens nor did analysis of variance detect any significant differences (alpha = 0.01) in the area under the curve of blood, urine or brain specimens at three identical DFE concentrations. The method is suitable for use in forensic laboratories because validation was performed on instrumentation routinely used in forensic labs and due to the ease with which the calibration range can be adjusted. Perhaps more importantly it is also useful for research oriented studies because the removal of solvent from standard preparation eliminates the possibility for solvent induced changes to the gas/liquid partitioning of DFE or chromatographic interference due to the presence of solvent in specimens.

Tau protein (MAPT) as a possible biochemical marker of traumatic brain injury in postmortem examination.

PubMed

Olczak, Mieszko; Niderla-Bielińska, Justyna; Kwiatkowska, Magdalena; Samojłowicz, Dorota; Tarka, Sylwia; Wierzba-Bobrowicz, Teresa

2017-11-01

MAPT is a neuronal protein that plays an important role in axonal stabilization, neuronal development, and neuronal polarity. MAPT release into the CSF and blood has been interpreted as indicative of axonal injury as its elevated levels were observed in olympic boxers even after a mild head trauma suggesting minor CNS injuries. In our study we wanted to check the potential relevance of MAPT examination for forensic purposes. The study was carried out using cases of head injury group and cases of sudden death (cardiopulmonary failure, no injuries of the head - control group) provided by forensic pathologists at the Department of Forensic Medicine, Medical University of Warsaw. CSF and blood were collected within 24h after death using suboccipital puncture and femoral vein puncture. Serum and cerebrospinal fluid Tau protein concentrations were compared using an enzyme-linked immunosorbent assay (elisa). Brain specimens (frontal cortex) were collected during forensic autopsies. Sections were stained histologically (hematoxylin-eosin) and immunohistochemically with anti human Tau antibody, anti glial fibrillary acid protein (GFAP), anti human macrosialin (CD68) or anti human endothelial cells (CD34). In our study we documented that elevated levels of serum and CSF MAPT may also be considered a marker for mild traumatic brain injury and traumatic brain injury (mTBI and TBI). An increase in CSF and serum levels of MAPT in the absence of visible macroscopic traumatic CNS changes indicates that even minor head injuries may result in changes at the neuronal level that could remain undiagnosed during regular forensic autopsy and routine histopathological examination. Copyright © 2017 Elsevier B.V. All rights reserved.

An unusual occupational accident: fall into a sewage plant tank with lethal outcome.

PubMed

Padosch, Stephan A; Dettmeyer, Reinhard B; Kröner, Lars U; Preuss, Johanna; Madea, Burkhard

2005-04-20

Occupational accidents, often presenting with lethal outcomes, are a rarely reported issue in forensic literature. However, these incidents are part of medicolegal casework with special regard to reconstruction, liabilities and insurance law-related issues, respectively. We report on a lethal occupational accident in a metropolitan sewage plant. When performing routine controls, a technician fell into an overflow sewer and was immediately pulled into a 30 cm diameter drain. Rescue efforts were initiated immediately, but had to be terminated due to gas warning. Rescue teams continued the search, however, the body remained undiscoverable. Forty-eight hours later, the cadaver was found in an adjacent digester tank, from where it was finally rescued. It was concluded, that the body had been transported between the overflow sewer and the digester tank through a 120 m pipeline with several 90 degrees bendings and branch connections with a minimum diameter of 25 cm at the discharge valve. On medicolegal examination, the cadaver showed marked signs of advanced decomposition caused by anaerobic microorganisms in the 37 degrees C biomass environment. Moreover, as a consequence of the passage of the pipeline system, signs of massive trauma (several comminuted and compound fractures) were disclosed at autopsy. To us, this is the first report on a lethal occupational accident in a sewage plant; our observations demonstrate the rapid progress of putrefaction in a warm anaerobic bacterial environment and the massive trauma sustained.

First practical applications of eye temperature measurements for estimation of the time of death in casework. Report of three cases.

PubMed

Kaliszan, Michał

2012-06-10

This paper presents first three successive cases of death where at scene measurements of the internal eyeball temperature soon after death allowed to precisely estimate the times of deaths based on this data (33.1°C, 32.2°C and 29.5°C, respectively), which were later confirmed during the police investigation. Simultaneously the rectal temperatures in all three cases were measured and appeared to be between 36.3 and 36.8°C-reflecting a living individual's body temperature. Thanks to a significantly faster postmortem decrease of the eye temperature and a residual or nonexistent plateau effect affecting the eye, using the formula developed in previous comprehensive studies in pigs, the time of death in real cases could be estimated with good precision: 1 h 33 min, 2 h 24 min and 3 h 17 min since death respectively. The actual TOD established during investigation appeared to be: between 1 h 30 min and 1 h 50 min in case 1; 1 h 55 min in case 2 and between 2 h 55 min and 3 h 05 min in case 3. Such precise estimation, mainly due to the plateau effect lasting up to a few hours, could not have been done based only on rectal temperature, commonly measured in forensic practice. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

Quantification of suvorexant in blood using liquid chromatography-quadrupole/time of flight (LC-Q/TOF) mass spectrometry.

PubMed

Skillman, Britni; Kerrigan, Sarah

2018-08-01

Suvorexant is a novel drug for the treatment of insomnia that is marketed under the trade name Belsomra®. Unlike other hypnotics, suvorexant is a dual orexin receptor antagonist that is believed to have a lower abuse potential compared to other therapeutics. Although sedative hypnotics feature prominently in forensic toxicology investigations, there have been limited reports that describe the analysis of suvorexant in biological samples. Following a 10-mg oral dose, peak concentrations are typically <200 ng/mL. A highly sensitive assay is required because forensic toxicology laboratories are often required to identify a drug several hours after a single dose. A new analytical procedure for the quantification of suvorexant in whole blood was developed that will aid in the identification of this new drug in forensic toxicology casework. A simple acidic/neutral liquid-liquid extraction (LLE) was used to isolate suvorexant from whole blood followed by liquid chromatography-quadrupole/time of flight (LC-Q/TOF) mass spectrometry analysis using positive electrospray ionization (ESI). The extraction efficiencies of various solvents in blood were evaluated in addition to limit of detection, limit of quantitation, precision, accuracy and bias, calibration model, matrix effects, interferences, and carryover. The recovery of suvorexant was evaluated using four different extraction solvents (N-butyl chloride, ether/toluene (1:1), hexane/ethyl acetate (9:1), and methyl tert-butyl ether (MTBE). Although no significant differences in analytical recovery were observed, N-butyl chloride demonstrated improved reproducibility, efficiency and convenience. A weighted (1/x) quadratic calibration model was selected over a range of 2-200 ng/mL (R 2  = 0.995). Using only 0.5 mL whole blood, limits of detection and quantification were 0.5 ng/mL. Intra-assay (n = 5) and inter-assay (n = 15) precision (% CV) were ≤ 13% and bias ranged from -5 to 2% at concentrations of 5, 50, and 160 ng/mL. Matrix effects were 16% (9% CV) and 15% (8% CV) for 20 ng/mL and 100 ng/mL (n = 20), respectively. No qualitative interferences or carryover were observed; however, a quantitative interference with the internal standard (estazolam-D5) could be attributed to sertraline when present at a 10-fold higher concentration. In the absence of a commercially available deuterated internal standard, the potential for quantitative interferences using LC-based methods are discussed. Copyright © 2018 Elsevier B.V. All rights reserved.

Isolation of the Male-Specific Transformer Exon as a Method for Immature Specimen Sex Identification in Chrysomya megacephala (Diptera: Calliphoridae).

PubMed

Smith, J L; Wells, J D

2017-03-01

Being able to efficiently differentiate between male and female individuals in the immature forms of insects allows for investigations into sexually dimorphic patterns of growth rates and gene expression. For species lacking sex-specific morphological characteristics during these periods, alternative methods must be devised. Commonly, isolation of sex determination genes reveals sex-specific band patterns and allows for markers that can be used in insect control. For blow flies, a family that includes flies of medical and forensic importance, sex has previously been identified in some members using the male-specific exon in the transformer gene. This gene is relatively conserved between members of the genera Cochliomyia and Lucilia (Diptera: Calliphoridae), and we isolated a portion of this gene in an additional forensically and medically important blow fly genus using the widespread Chrysomya megacephala (F.). We found a relatively high level of conservation between exons 1 and 2 of transformer and were able to amplify a region containing the male-specific exon in C. megacephala. A sex-specific molecular diagnostic test based on the presence of sexually dimorphic PCR product bands showed the expected genotype for adults and intrapuparial period specimens of known sex. The same result could be obtained from single third-instar larval specimens, opening up the possibility to not only determine if development rates are sex dependent, but also to investigate the development of sexually dimorphic traits of interest in C. megacephala. © The Authors 2016. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Medico-legal significance of the identification of offending snake in a fatal snake bite: a case report.

PubMed

Silva, Anjana; Gamlaksha, Dayal; Waidyaratne, Dhananjaya

2013-11-01

A 19 year old male was admitted to a tertiary care centre in Sri Lanka, with a history of snake bite while sleeping at night. A killed specimen of a snake was brought with the patient. It had been identified as a non-venomous snake by the doctor and handed over to relatives, with a comment to that effect. Patient had no clinical or laboratory evidence of envenoming on admission. Patient developed bilateral ptosis six hours after alleged snake bite, soon followed by respiratory paralysis and was treated with Indian polyvalent anti-venom serum. After 12 h of the bite, patient had developed hypotension that did not respond to ionotropes. Despite intensive management, patient had become deeply comatose and deceased 46 h following the snake bite. Autopsy revealed features suggestive of disseminated intravascular coagulation. Since an allegation of medical negligence too had been levelled by the relations of the patient against the clinical staff, the buried specimen of the snake was recovered by police, on a judicial order, a week later. It was found to be almost completely disintegrated and only the scales and bones were remaining. According to the scale characters, the reconstructed specimen was identified as Indian krait (Bungarus caeruleus). Authentication of snake is important in investigating a death due to snake bite, especially when the snake was initially claimed to be a non-venomous snake. This case suggests the usefulness of forensic identification of species of the snake in investigating suspected snake bite cases. Copyright © 2013 Elsevier Ltd and Faculty of Forensic and Legal Medicine. All rights reserved.

Problems in Mitochondrial DNA forensics: while interpreting length heteroplasmy conundrum of various Sindhi and Baluchi ethnic groups of Pakistan.

PubMed

Bhatti, Shahzad; Aslam Khan, Muhammad; Abbas, Sana; Attimonelli, Marcella; Gonzalez, Gerardo Rodriguez; Aydin, Hikmet Hakan; de Souza, Erica Martinha Silva

2018-05-01

The insight heterodox genetics of mtDNA infer new perspectives at the level of human mitochondrial control region heteroplasmy, which is substantial in evolutionary as well as forensic interpretation. The main goal of this study is to interrogate the recurrence and resolve the ambiguity of blurry spectrum of heteroplasmy in the human mtDNA control region of 50 Baluchi and 116 Sindhi unrelated individuals. Sanger sequencing was employed classically, that was further investigated by minisequencing. Only 20% Baluchi and 25.8% Sindhi were homoplasmic, whereas rest of 80% Baluchi and 74.1% Sindhi exhibited at least one heteroplasmy within the specimen. In total, 166 individuals have length heteroplasmy (LH) found at positions 16189, 303-315, 568-573, and 514-524, whilst point mutation heteroplasmy (PMH) was detected at positions 73, 16093, 16189, and 16234, respectively. Overall LH was observed albeit high frequency in Sindhi ethnic group (82%) rather than Baluchi's (37%), whereas PMH accumulation was relatively extensive (24%) in Baluchi's than Sindhi's (11.2%). The obtained results ascertained that growing knowledge of heteroplasmy assisted to develop consciences in the forensic community that heteroplasmy plays a pivotal role in the legal interpretation on a regular basis and knowledge of its biological underpinnings has a vital niche in the forensic science. Limited studies have focused on heteroplasmy, yet scientific attention should be given, in order to determine its magnitude in different ethnic boundaries.

[The physician as Sherlock Holmes. Accident, murder by poisoning or suicide?].

PubMed

Penning, R

2001-12-06

Any case of unclear or atypical clinical presentation must arouse a suspicion of poisoning. Although pathognomonic findings are rare, there may nevertheless be an accumulation of signs and symptoms. These include impairment of consciousness, vertigo, headache, circulatory disorders, cramps/convulsions, vomiting, diarrhea and abdominal pains. Forensic terminology differentiates between outside influence, self-poisoning and accidental poisoning. In the former case, substances are used that are deadly in small amounts, and are unremarkable in appearance, smell and taste. The poisons used by suicides are usually commonly used poisonous substances that are freely available to purchasers. For forensic purposes, it is essential that specimens of blood, urine or stomach contents be obtained for toxicological investigations. Inspection of the corpse must routinely include a search for unusual signs (e.g. traces of powder around the mouth, foam at the mouth and nose, desiccation, unusual postmortem lividity, hair loss, etc.).

Hair: a complementary source of bioanalytical information in forensic toxicology.

PubMed

Barroso, Mário; Gallardo, Eugenia; Vieira, Duarte Nuno; López-Rivadulla, Manuel; Queiroz, João António

2011-01-01

Hair has been used for years in the assessment and documentation of human exposure to drugs, as it presents characteristics that make it extremely valuable for this purpose, namely the fact that sample collection is performed in a noninvasive manner, under close supervision, the possibility of collecting a specimen reflecting a similar timeline in the case of claims or suspicion of a leak in the chain of custody, and the increased window of detection for the drugs. For these reasons, testing for drugs in hair provides unique and useful information in several fields of toxicology, from which the most prominent is the possibility of studying individual drug use histories by means of segmental analysis. This paper will review the unique role of hair as a complementary sample in documenting human exposure to drugs in the fields of clinical and forensic toxicology and workplace drug testing.

[Research Progress on Forensic Toxicology of Z-drugs].

PubMed

Zhang, Yong-zhi; He, Hong-yuan; She, Cai-meng; Lian, Jie

2015-08-01

The Z-drugs (zolpidem, zopiclone, and zaleplon), as the innovative hypnotics, have an improvement over the traditional benzodiazepines in the management of insomnia. Z-drugs have significant hypnotic effects by reducing sleep latency and improving sleep quality, though duration of sleep may not be significantly increased. As benzodiazepines, Z-drugs exert their effects through increasing the transmission of γ-aminobutyric acid. Z-drugs overdose are less likely to be fatal, more likely would result in poisoning. Z-drugs can be detected in blood, urine, saliva, and other postmortem specimens through liquid chromatography-mass spectrometry techniques. Zolpidem and zaleplon exhibit significant postmortem redistribution. Z-drugs have improved pharmacokinetic profiles, but incidence of neuropsychiatric sequelae, poisoning, and death may prove to be similar to the other hypnotics. This review focuses on the pharmacology and toxicology of Z-drugs with respect to their adverse effect profile and toxicity and toxicology data in the field of forensic medicine.

Validation of a DNA IQ-based extraction method for TECAN robotic liquid handling workstations for processing casework.

PubMed

Frégeau, Chantal J; Lett, C Marc; Fourney, Ron M

2010-10-01

A semi-automated DNA extraction process for casework samples based on the Promega DNA IQ™ system was optimized and validated on TECAN Genesis 150/8 and Freedom EVO robotic liquid handling stations configured with fixed tips and a TECAN TE-Shake™ unit. The use of an orbital shaker during the extraction process promoted efficiency with respect to DNA capture, magnetic bead/DNA complex washes and DNA elution. Validation studies determined the reliability and limitations of this shaker-based process. Reproducibility with regards to DNA yields for the tested robotic workstations proved to be excellent and not significantly different than that offered by the manual phenol/chloroform extraction. DNA extraction of animal:human blood mixtures contaminated with soil demonstrated that a human profile was detectable even in the presence of abundant animal blood. For exhibits containing small amounts of biological material, concordance studies confirmed that DNA yields for this shaker-based extraction process are equivalent or greater to those observed with phenol/chloroform extraction as well as our original validated automated magnetic bead percolation-based extraction process. Our data further supports the increasing use of robotics for the processing of casework samples. Crown Copyright © 2009. Published by Elsevier Ireland Ltd. All rights reserved.

Practice-Informed Approaches to Addressing Substance Abuse and Trauma Exposure in Urban Native Families Involved with Child Welfare.

PubMed

Lucero, Nancy M; Bussey, Marian

2015-01-01

Similar to families from other groups, urban-based American Indian and Alaska Native ("Native") family members involved with the child welfare system due to substance abuse issues are also often challenged by untreated trauma exposure. The link between these conditions and the history of genocidal policies aimed at destroying Native family ties, as well as experiences of ongoing discrimination, bring added dimensions for consideration when pro- viding services to these families. Practice-based evidence indicates that the trauma-informed and culturally responsive model developed by the Denver Indian Family Resource Center (DIFRC) shows promise in reducing out-of-home placements and re-referrals in urban Native families with substance abuse and child welfare concerns, while also increasing caregiver capabilities, family safety, and child well-being. This article provides strategies from the DIFRC approach that non-Native caseworkers and supervisors can utilize to create an environment in their own agencies that supports culturally based practice with Native families while incorporating a trauma-informed understanding of service needs of these families. Casework consistent with this approach demonstrates actions that meet the Active Efforts requirement of the Indian Child Welfare Act (ICWA) as well as sound clinical practice. Intensive and proactive case management designed specifically for families with high levels of service needs is a key strategy when combined with utilizing a caseworker brief screening tool for trauma exposure; training caseworkers to recognize trauma symptoms, making timely referrals to trauma treatment by behavioral health specialists experienced in working with Native clients, and providing a consistent service environment that focuses on client safety and worker trustworthiness. Finally, suggestions are put forth for agencies seeking to enhance their cultural responsiveness and include increasing workers' understanding of cultural values, worldview, and historical issues; working from a relational perspective; listening deeply to families' experiences; and being open to incorporating traditional healing and cultural practice into service plans.

DNA Barcode Authentication and Library Development for the Wood of Six Commercial Pterocarpus Species: the Critical Role of Xylarium Specimens.

PubMed

Jiao, Lichao; Yu, Min; Wiedenhoeft, Alex C; He, Tuo; Li, Jianing; Liu, Bo; Jiang, Xiaomei; Yin, Yafang

2018-01-31

DNA barcoding has been proposed as a useful tool for forensic wood identification and development of a reliable DNA reference library is an essential first step. Xylaria (wood collections) are potentially enormous data repositories if DNA information could be extracted from wood specimens. In this study, 31 xylarium wood specimens and 8 leaf specimens of six important commercial species of Pterocarpus were selected to investigate the reliability of DNA barcodes for authentication at the species level and to determine the feasibility of building wood DNA barcode reference libraries from xylarium specimens. Four DNA barcodes (ITS2, matK, ndhF-rpl32 and rbcL) and their combination were tested to evaluate their discrimination ability for Pterocarpus species with both TaxonDNA and tree-based analytical methods. The results indicated that the combination barcode of matK + ndhF-rpl32 + ITS2 yielded the best discrimination for the Pterocarpus species studied. The mini-barcode ndhF-rpl32 (167-173 bps) performed well distinguishing P. santalinus from its wood anatomically inseparable species P. tinctorius. Results from this study verified not only the feasibility of building DNA barcode libraries using xylarium wood specimens, but the importance of using wood rather than leaves as the source tissue, when wood is the botanical material to be identified.

FT Raman microscopy of untreated natural plant fibres

NASA Astrophysics Data System (ADS)

Edwards, H. G. M.; Farwell, D. W.; Webster, D.

1997-11-01

The application of FT-Raman microscopy to the non-destructive analysis of natural plant fibres is demonstrated with samples of flax, jute, ramie, cotton, kapok, sisal and coconut fibre. Vibrational assignments are proposed and characteristic features of each material are presented. Samples were not pre-treated chemically before analysis and were used directly from their respective storage collection; the adaptation of the Raman microscopic technique to the identification of specimens of natural fibres in archaeological burial sites is explored for its forensic potential.

Comparison of hard tissues that are useful for DNA analysis in forensic autopsy.

PubMed

Kaneko, Yu; Ohira, Hiroshi; Tsuda, Yukio; Yamada, Yoshihiro

2015-11-01

Forensic analysis of DNA from hard tissues can be important when investigating a variety of cases resulting from mass disaster or criminal cases. This study was conducted to evaluate the most suitable tissues, method and sample size for processing of hard tissues prior to DNA isolation. We also evaluated the elapsed time after death in relation to the quantity of DNA extracted. Samples of hard tissues (37 teeth, 42 skull, 42 rib, and 39 nails) from 42 individuals aged between 50 and 83 years were used. The samples were taken from remains following forensic autopsy (from 2 days to 2 years after death). To evaluate the integrity of the nuclear DNA isolated, the percentage of allele calls for short tandem repeat profiles were compared between the hard tissues. DNA typing results indicated that until 1 month after death, any of the four hard tissue samples could be used as an alternative to teeth, allowing analysis of all of the loci. However, in terms of the sampling site, collection method and sample size adjustment, the rib appeared to be the best choice in view of the ease of specimen preparation. Our data suggest that the rib could be an alternative hard tissue sample for DNA analysis of human remains. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Forensic entomology cases in Thailand: a review of cases from 2000 to 2006.

PubMed

Sukontason, Kom; Narongchai, Paitoon; Kanchai, Chaturong; Vichairat, Karnda; Sribanditmongkol, Pongruk; Bhoopat, Tanin; Kurahashi, Hiromu; Chockjamsai, Manoch; Piangjai, Somsak; Bunchu, Nophawan; Vongvivach, Somsak; Samai, Wirachai; Chaiwong, Tarinee; Methanitikorn, Rungkanta; Ngern-Klun, Rachadawan; Sripakdee, Duanghatai; Boonsriwong, Worachote; Siriwattanarungsee, Sirisuda; Srimuangwong, Chaowakit; Hanterdsith, Boonsak; Chaiwan, Khankam; Srisuwan, Chalard; Upakut, Surasak; Moopayak, Kittikhun; Vogtsberger, Roy C; Olson, Jimmy K; Sukontason, Kabkaew L

2007-10-01

This paper presents and discusses 30 cases of cadavers that had been transferred for forensic entomology investigations to the Department of Forensic Medicine, Faculty of Medicine, Chiang Mai University, northern Thailand, from 2000 to 2006. Variable death scenes were determined, including forested area and suburban and urban outdoor and indoor environments. The fly specimens found in the corpses obtained were the most commonly of the blow fly of family Calliphoridae, and consisted of Chrysomya megacephala (F.), Chrysomya rufifacies (Macquart) Chrysomya villeneuvi Patton, Chrysomya nigripes Aubertin, Chrysomya bezziana Villeneuve, Chrysomya chani Kurahashi, Lucilia cuprina (Wiedemann), Hemipyrellia ligurriens (Wiedemann), and two unknown species. Flies of the family Muscidae [Hydrotaea spinigera Stein, Synthesiomyia nudiseta (Wulp)], Piophilidae [Piophila casei (L.)], Phoridae [Megaselia scalaris (Loew)], Sarcophagidae [Parasarcophaga ruficornis (F.) and three unknown species], and Stratiomyiidae (Sargus sp.) were also collected from these human remains. Larvae and adults of the beetle, Dermestes maculatus DeGeer (Coleoptera: Dermestidae), were also found in some cases. Chrysomya megacephala and C. rufifacies were the most common species found in the ecologically varied death scene habitats associated with both urban and forested areas, while C. nigripes was commonly discovered in forested places. S. nudiseta was collected only from corpses found in an indoor death scene.

Development of modern human subadult age and sex estimation standards using multi-slice computed tomography images from medical examiner's offices

NASA Astrophysics Data System (ADS)

Stock, Michala K.; Stull, Kyra E.; Garvin, Heather M.; Klales, Alexandra R.

2016-10-01

Forensic anthropologists are routinely asked to estimate a biological profile (i.e., age, sex, ancestry and stature) from a set of unidentified remains. In contrast to the abundance of collections and techniques associated with adult skeletons, there is a paucity of modern, documented subadult skeletal material, which limits the creation and validation of appropriate forensic standards. Many are forced to use antiquated methods derived from small sample sizes, which given documented secular changes in the growth and development of children, are not appropriate for application in the medico-legal setting. Therefore, the aim of this project is to use multi-slice computed tomography (MSCT) data from a large, diverse sample of modern subadults to develop new methods to estimate subadult age and sex for practical forensic applications. The research sample will consist of over 1,500 full-body MSCT scans of modern subadult individuals (aged birth to 20 years) obtained from two U.S. medical examiner's offices. Statistical analysis of epiphyseal union scores, long bone osteometrics, and os coxae landmark data will be used to develop modern subadult age and sex estimation standards. This project will result in a database of information gathered from the MSCT scans, as well as the creation of modern, statistically rigorous standards for skeletal age and sex estimation in subadults. Furthermore, the research and methods developed in this project will be applicable to dry bone specimens, MSCT scans, and radiographic images, thus providing both tools and continued access to data for forensic practitioners in a variety of settings.

Poisons Implicated In Homicidal, Suicidal And Accidental Cases In North-West Pakistan.

PubMed

Jan, Adil; Khan, Muhammad Jaffar; Humayun Khan, Muhammad Tariq; Masood Khan, Muhammad Tariq; Fatima, Sadia

2016-01-01

Pakistan has one of the highest prevalence of poisoning in the world. However, limited data exist on the frequency of poisons implicated in homicidal, suicidal, and accidental cases in North-West Pakistan (Khyber Pakhtunkhwa). This retrospective study of 353 cases and biological specimens of poisoning received at the department of Forensic medicine and toxicology, Khyber Medical College Peshawar from 13 districts of Khyber Pakhtunkhwa. Frequency of poisoning was assessed by testing each specimen for 17 different poisons. Of all the specimens, 250 (70.8%) specimens tested positive and the rest didn't show any indication of poisoning (n=103, 29.2%). The most frequent poisons detected were benzodiazepines (total n=75), organophosphates (total n=58), phencyclidine (total n=30) and morphine (total n=23). Gender had a significant association with benzodiazepines (p=0.011), tricyclic antidepressants (p=0.001), and organophosphates (p<0.001). Organophosphates were the most common cause of poisoning in females while benzodiazepines were the most common cause of poisoning in males. Poisoning by benzodiazepines, organophosphates and phencyclidine are the most common causes of intoxication in population of Khyber Pakhtunkhwa. Source of poisoning varies with gender for organophosphates, benzodiazepines and tricyclic antidepressants.

The Qiagen Investigator® Quantiplex HYres as an alternative kit for DNA quantification.

PubMed

Frégeau, Chantal J; Laurin, Nancy

2015-05-01

The Investigator® Quantiplex HYres kit was evaluated as a potential replacement for dual DNA quantification of casework samples. This kit was determined to be highly sensitive with a limit of quantification and limit of detection of 0.0049ng/μL and 0.0003ng/μL, respectively, for both human and male DNA, using full or half reaction volumes. It was also accurate in assessing the amount of male DNA present in 96 mock and actual casework male:female mixtures (various ratios) processed in this exercise. The close correlation between the male/human DNA ratios expressed in percentages derived from the Investigator® Quantiplex HYres quantification results and the male DNA proportion calculated in mixed AmpFlSTR® Profiler® Plus or AmpFlSTR® Identifiler® Plus profiles, using the Amelogenin Y peak and STR loci, allowed guidelines to be developed to facilitate decisions regarding when to submit samples to Y-STR rather than autosomal STR profiling. The internal control (IC) target was shown to be more sensitive to inhibitors compared to the human and male DNA targets included in the Investigator® Quantiplex HYres kit serving as a good quality assessor of DNA extracts. The new kit met our criteria of enhanced sensitivity, accuracy, consistency, reliability and robustness for casework DNA quantification. Crown Copyright © 2015. Published by Elsevier Ireland Ltd. All rights reserved.

Biomechanical Studies on Patterns of Cranial Bone Fracture Using the Immature Porcine Model.

PubMed

Haut, Roger C; Wei, Feng

2017-02-01

This review was prepared for the American Society of Mechanical Engineers Lissner Medal. It specifically discusses research performed in the Orthopaedic Biomechanics Laboratories on pediatric cranial bone mechanics and patterns of fracture in collaboration with the Forensic Anthropology Laboratory at Michigan State University. Cranial fractures are often an important element seen by forensic anthropologists during the investigation of pediatric trauma cases litigated in courts. While forensic anthropologists and forensic biomechanists are often called on to testify in these cases, there is little basic science developed in support of their testimony. The following is a review of studies conducted in the above laboratories and supported by the National Institute of Justice to begin an understanding of the mechanics and patterns of pediatric cranial bone fracture. With the lack of human pediatric specimens, the studies utilize an immature porcine model. Because much case evidence involves cranial bone fracture, the studies described below focus on determining input loading based on the resultant bone fracture pattern. The studies involve impact to the parietal bone, the most often fractured cranial bone, and begin with experiments on entrapped heads, progressing to those involving free-falling heads. The studies involve head drops onto different types and shapes of interfaces with variations of impact energy. The studies show linear fractures initiating from sutural boundaries, away from the impact site, for flat surface impacts, in contrast to depressed fractures for more focal impacts. The results have been incorporated into a "Fracture Printing Interface (FPI)," using machine learning and pattern recognition algorithms. The interface has been used to help interpret mechanisms of injury in pediatric death cases collected from medical examiner offices. The ultimate aim of this program of study is to develop a "Human Fracture Printing Interface" that can be used by forensic investigators in determining mechanisms of pediatric cranial bone fracture.

A preliminary study on postmortem interval estimation of suffocated rats by GC-MS/MS-based plasma metabolic profiling.

PubMed

Sato, Takako; Zaitsu, Kei; Tsuboi, Kento; Nomura, Masakatsu; Kusano, Maiko; Shima, Noriaki; Abe, Shuntaro; Ishii, Akira; Tsuchihashi, Hitoshi; Suzuki, Koichi

2015-05-01

Estimation of postmortem interval (PMI) is an important goal in judicial autopsy. Although many approaches can estimate PMI through physical findings and biochemical tests, accurate PMI calculation by these conventional methods remains difficult because PMI is readily affected by surrounding conditions, such as ambient temperature and humidity. In this study, Sprague-Dawley (SD) rats (10 weeks) were sacrificed by suffocation, and blood was collected by dissection at various time intervals (0, 3, 6, 12, 24, and 48 h; n = 6) after death. A total of 70 endogenous metabolites were detected in plasma by gas chromatography-tandem mass spectrometry (GC-MS/MS). Each time group was separated from each other on the principal component analysis (PCA) score plot, suggesting that the various endogenous metabolites changed with time after death. To prepare a prediction model of a PMI, a partial least squares (or projection to latent structure, PLS) regression model was constructed using the levels of significantly different metabolites determined by variable importance in the projection (VIP) score and the Kruskal-Wallis test (P < 0.05). Because the constructed PLS regression model could successfully predict each PMI, this model was validated with another validation set (n = 3). In conclusion, plasma metabolic profiling demonstrated its ability to successfully estimate PMI under a certain condition. This result can be considered to be the first step for using the metabolomics method in future forensic casework.

Developmental validation of the PowerPlex(®) Fusion System for analysis of casework and reference samples: A 24-locus multiplex for new database standards.

PubMed

Oostdik, Kathryn; Lenz, Kristy; Nye, Jeffrey; Schelling, Kristin; Yet, Donald; Bruski, Scott; Strong, Joshua; Buchanan, Clint; Sutton, Joel; Linner, Jessica; Frazier, Nicole; Young, Hays; Matthies, Learden; Sage, Amber; Hahn, Jeff; Wells, Regina; Williams, Natasha; Price, Monica; Koehler, Jody; Staples, Melisa; Swango, Katie L; Hill, Carolyn; Oyerly, Karen; Duke, Wendy; Katzilierakis, Lesley; Ensenberger, Martin G; Bourdeau, Jeanne M; Sprecher, Cynthia J; Krenke, Benjamin; Storts, Douglas R

2014-09-01

The original CODIS database based on 13 core STR loci has been overwhelmingly successful for matching suspects with evidence. Yet there remain situations that argue for inclusion of more loci and increased discrimination. The PowerPlex(®) Fusion System allows simultaneous amplification of the following loci: Amelogenin, D3S1358, D1S1656, D2S441, D10S1248, D13S317, Penta E, D16S539, D18S51, D2S1338, CSF1PO, Penta D, TH01, vWA, D21S11, D7S820, D5S818, TPOX, DYS391, D8S1179, D12S391, D19S433, FGA, and D22S1045. The comprehensive list of loci amplified by the system generates a profile compatible with databases based on either the expanded CODIS or European Standard Set (ESS) requirements. Developmental validation testing followed SWGDAM guidelines and demonstrated the quality and robustness of the PowerPlex(®) Fusion System across a number of variables. Consistent and high-quality results were compiled using data from 12 separate forensic and research laboratories. The results verify that the PowerPlex(®) Fusion System is a robust and reliable STR-typing multiplex suitable for human identification. Copyright © 2014 The Authors. Published by Elsevier Ireland Ltd.. All rights reserved.

A panel of 130 autosomal single-nucleotide polymorphisms for ancestry assignment in five Asian populations and in Caucasians.

PubMed

Hwa, Hsiao-Lin; Lin, Chih-Peng; Huang, Tsun-Ying; Kuo, Po-Hsiu; Hsieh, Wei-Hsin; Lin, Chun-Yen; Yin, Hsiang-I; Tseng, Li-Hui; Lee, James Chun-I

2017-06-01

Ancestry informative single-nucleotide polymorphism (AISNP) panels for differentiating between East and Southeast Asian populations are scarce. This study aimed to identify AISNPs for ancestry assignment of five East and Southeast Asian populations, and Caucasians. We analyzed 145 autosomal SNPs of the 627 DNA samples from individuals of six populations (234 Taiwanese Han, 91 Filipinos, 79 Indonesians, 60 Thais, 71 Vietnamese, and 92 Caucasians) using arrays. The multiple logistic regression model and a multi-tier approach were used for ancestry classification. We observed that 130 AISNPs were effective for classifying the ethnic origins with fair accuracy. Among the 130 AISNPs, 122 were useful for stratification between these five Asian populations and 64 were effective for differentiating between Caucasians and these Asian populations. For differentiation between Caucasians and Asians, an accuracy rate of 100% was achieved in these 627 subjects with 50 optimal AISNPs among the 64 effective SNPs. For classification of the five Asian populations, the accuracy rates of ancestry inference using 20 to 57 SNPs for each of the two Asian populations ranged from 74.1% to 100%. Another 14 degraded DNA samples with incomplete profiling were analyzed, and the ancestry of 12 (85.7%) of those subjects was accurately assigned. We developed a 130-AISNP panel for ethnic origin differentiation between the five East and Southeast Asian populations and Caucasians. This AISNP set may be helpful for individual ancestral assignment of these populations in forensic casework.

Ivory species identification using electrophoresis-based techniques.

PubMed

Kitpipit, Thitika; Thanakiatkrai, Phuvadol; Penchart, Kitichaya; Ouithavon, Kanita; Satasook, Chutamas; Linacre, Adrian

2016-12-01

Despite continuous conservation efforts by national and international organizations, the populations of the three extant elephant species are still dramatically declining due to the illegal trade in ivory leading to the killing of elephants. A requirement to aid investigations and prosecutions is the accurate identification of the elephant species from which the ivory was removed. We report on the development of the first fully validated multiplex PCR-electrophoresis assay for ivory DNA analysis that can be used as a screening or confirmatory test. SNPs from the NADH dehydrogenase 5 and cytochrome b gene loci were identified and used in the development of the assay. The three extant elephant species could be identified based on three peaks/bands. Elephas maximus exhibited two distinct PCR fragments at approximate 129 and 381 bp; Loxodonta cyclotis showed two PCR fragments at 89 and 129 bp; and Loxodonta africana showed a single fragment of 129 bp. The assay correctly identified the elephant species using all 113 ivory and blood samples used in this report. We also report on the high sensitivity and specificity of the assay. All single-blinded samples were correctly classified, which demonstrated the assay's ability to be used for real casework. In addition, the assay could be used in conjunction with the technique of direct amplification. We propose that the test will benefit wildlife forensic laboratories and aid in the transition to the criminal justice system. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

The transfer of diatoms from freshwater to footwear materials: An experimental study assessing transfer, persistence, and extraction methods for forensic reconstruction.

PubMed

Levin, E A; Morgan, R M; Scott, K R; Jones, V J

2017-09-01

In recent years there has been growing interest in environmental forms of trace evidence, and ecological trace evidence collected from footwear has proved valuable within casework. Simultaneously, there has been growing awareness of the need for empirical experimentation to underpin forensic inferences. Diatoms are unicellular algae, and each cell (or 'frustule') consists of two valves which are made of silica, a robust material that favours their preservation both in sediments and within forensic scenarios. A series of experiments were carried out to investigate the transfer and persistence of diatoms upon common footwear materials, a recipient surface that has historically been overlooked by studies of persistence. The effectiveness of two novel extraction techniques (jet rinsing, and heating and agitation with distilled water) was compared to the established extraction technique of hydrogen peroxide digestion, for a suite of five common footwear materials: canvas, leather, and 'suede' (representing upper materials), and rubber and polyurethane (representing sole materials). It was observed that the novel extraction technique of heating and agitation with distilled water did not extract fewer diatom valves, or cause increased fragmentation of valves, when compared to peroxide digestion, suggesting that the method may be viable where potentially hazardous chemical reactions may be encountered with the peroxide digestion method. Valves could be extracted from all five footwear materials after 3min of immersion, and more valves were extracted from the rougher, woven upper materials than the smoother sole materials. Canvas yielded the most valves (a mean of 2511/cm 2 ) and polyurethane the fewest (a mean of 15/cm 2 ). The persistence of diatoms on the three upper materials was addressed with a preliminary pilot investigation, with ten intervals sampled between 0 and 168h. Valves were seen to persist in detectable quantities after 168h on all three upper materials. However, some samples produced slides with no valves, and the earliest time after which no diatom valves were found was 4h after the transfer. Analysis of the particle size distributions over time, by image analysis, suggests that the retention of diatoms may be size-selective; after 168h, no particles larger than 200μm 2 could be found on the samples of canvas, and >95% of the particles on the samples of suede were less than or equal to 200μm 2 . A pilot investigation into the effects of immersion interval was carried out upon samples of canvas. Greater numbers of valves were extracted from the samples with longer immersion intervals, but even after 30s, >500 valves could be recovered per cm 2 , suggesting that footwear may be sampled for diatoms even if the contact with a water body may have been brief. These findings indicate that, if the variability within and between experimental runs can be addressed, there is significant potential for diatoms to be incorporated into the trace analysis of footwear and assist forensic reconstructions. Copyright © 2017 The Authors. Published by Elsevier B.V. All rights reserved.

Injuries of the head from backface deformation of ballistic protective helmets under ballistic impact.

PubMed

Rafaels, Karin A; Cutcliffe, Hattie C; Salzar, Robert S; Davis, Martin; Boggess, Brian; Bush, Bryan; Harris, Robert; Rountree, Mark Steve; Sanderson, Ellory; Campman, Steven; Koch, Spencer; Dale Bass, Cameron R

2015-01-01

Modern ballistic helmets defeat penetrating bullets by energy transfer from the projectile to the helmet, producing helmet deformation. This deformation may cause severe injuries without completely perforating the helmet, termed "behind armor blunt trauma" (BABT). As helmets become lighter, the likelihood of larger helmet backface deformation under ballistic impact increases. To characterize the potential for BABT, seven postmortem human head/neck specimens wearing a ballistic protective helmet were exposed to nonperforating impact, using a 9 mm, full metal jacket, 124 grain bullet with velocities of 400-460 m/s. An increasing trend of injury severity was observed, ranging from simple linear fractures to combinations of linear and depressed fractures. Overall, the ability to identify skull fractures resulting from BABT can be used in forensic investigations. Our results demonstrate a high risk of skull fracture due to BABT and necessitate the prevention of BABT as a design factor in future generations of protective gear. © 2014 American Academy of Forensic Sciences.

Forensic entomology of decomposing humans and their decomposing pets.

PubMed

Sanford, Michelle R

2015-02-01

Domestic pets are commonly found in the homes of decedents whose deaths are investigated by a medical examiner or coroner. When these pets become trapped with a decomposing decedent they may resort to feeding on the body or succumb to starvation and/or dehydration and begin to decompose as well. In this case report photographic documentation of cases involving pets and decedents were examined from 2009 through the beginning of 2014. This photo review indicated that in many cases the pets were cats and dogs that were trapped with the decedent, died and were discovered in a moderate (bloat to active decay) state of decomposition. In addition three cases involving decomposing humans and their decomposing pets are described as they were processed for time of insect colonization by forensic entomological approach. Differences in timing and species colonizing the human and animal bodies were noted as was the potential for the human or animal derived specimens to contaminate one another at the scene. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

Chromatic variation of soot soiling: a possible marker for gunshot wounds in burnt bone.

PubMed

Amadasi, Alberto; Merli, Daniele; Brandone, Alberto; Cattaneo, Cristina

2014-01-01

Soot soiling is a crucial forensic parameter around gunshot lesions. Carbonization, however, can severely alter human tissues and mimic such clues. This study aims at evaluating the survival of soot soiling even after carbonization in bone. A total of 36 bovine ribs (half fleshed and half defleshed) were shot with two types of bullet (both 9-mm; full metal-jacketed and unjacketed) with a near-contact range. With unjacketed bullets, the shot left in every case a clear, black, and roughly round soot stain around the entrance wound, whereas full metal-jacketed bullets left no signs of soot. Every specimen then underwent calcination in an oven at 800°C. The analysis of the charred samples clearly showed the survival of the soot soiling in both fleshed and bony samples, with a clear correspondence with the former position, but with a different color (yellow). Thus, soot soiling may survive, although with a different color, even after charring. © 2013 American Academy of Forensic Sciences.

Determination of Fracture Patterns in Glass and Glassy Polymers.

PubMed

Baca, Allison C; Thornton, John I; Tulleners, Frederic A

2016-01-01

The study of fractures of glass, glassy-type materials, and plastic has long been of interest to the forensic community. The focus of this interest has been the use of glass and polymer fractures to associate items of evidence under the assumption that each fracture is different. Generally, it is well-accepted that deviations exist; however, the emphasis has been on classifying and predicting fracture rather than determining that each fracture is different. This study documented the controlled fracture patterns of 60 glass panes, 60 glass bottles, and 60 plastic tail light lens covers using both dynamic impact and static pressure methods under closely controlled conditions. Each pattern was intercompared, and based on the limited specimens tested in this study, the results illustrate that the fracture patterns are different. Further repetitive studies, under controlled conditions, will be needed to provide more statistical significance to the theory that each fracture forms a nonreproducible fracture pattern. © 2015 American Academy of Forensic Sciences.

Lessons Learned from Autopsying an Unidentified Body with Iodine-125 Seeds Implanted for Prostate Brachytherapy.

PubMed

Idota, Nozomi; Nakamura, Mami; Masui, Koji; Kakiuchi, Yasuhiro; Yamada, Kei; Ikegaya, Hiroshi

2017-03-01

We report here lessons learned from an autopsy case involving radioactive materials. We performed an autopsy of an unidentified mummified man with no available medical history whom from imaging findings we suspected had received radioactive seed implants for prostate brachytherapy. We returned the excised prostate and seeds to the body. A few days later, the body was identified by DNA matching and cremated. According to the man's medical record, he had undergone iodine-125 seeds implantation for prostate cancer 11 months earlier. We should have removed the radioactive seeds from the body to prevent radiation exposure to the bereaved family and/or environmental pollution due to cremation. Surprisingly, one seed was found in the stored prostate specimen. Forensic experts should be cognizant of the risk of both radiation exposure in the autopsy room and environmental pollution. We must remain abreast of the latest advances in medicine. © 2016 American Academy of Forensic Sciences.

Clinical Effects and Lethal and Forensic Aspects of Propofol*

PubMed Central

Levy, Richard J.

2010-01-01

Propofol is a potent intravenous anesthetic agent that rapidly induces sedation and unconsciousness. The potential for propofol dependency, recreational use and abuse has only recently been recognized and several cases of accidental overdose and suicide have emerged. In addition, the first documented case of murder using propofol was reported a few months ago and a high profile case of suspected homicide with propofol is currently under investigation. A number of analytical methods have been employed to detect and quantify propofol concentrations in biological specimens. The reported propofol related deaths and post-mortem blood and tissue levels are reviewed. Importantly, limitations of propofol detection are discussed and future considerations are presented. Because propofol has the potential for diversion with lethal consequences, the forensic scientist must have a basic understanding of its clinical indications and uses, pharmacologic properties, and detection methods. In addition, medical institutions should develop systems to prevent and detect diversion of this potential drug of abuse. PMID:20950316

DNA extraction and barcode identification of development stages of forensically important flies in the Czech Republic.

PubMed

Olekšáková, Tereza; Žurovcová, Martina; Klimešová, Vanda; Barták, Miroslav; Šuláková, Hana

2018-04-01

Several methods of DNA extraction, coupled with 'DNA barcoding' species identification, were compared using specimens from early developmental stages of forensically important flies from the Calliphoridae and Sarcophagidae families. DNA was extracted at three immature stages - eggs, the first instar larvae, and empty pupal cases (puparia) - using four different extraction methods, namely, one simple 'homemade' extraction buffer protocol and three commercial kits. The extraction conditions, including the amount of proteinase K and incubation times, were optimized. The simple extraction buffer method was successful for half of the eggs and for the first instar larval samples. The DNA Lego Kit and DEP-25 DNA Extraction Kit were useful for DNA extractions from the first instar larvae samples, and the DNA Lego Kit was also successful regarding the extraction from eggs. The QIAamp DNA mini kit was the most effective; the extraction was successful with regard to all sample types - eggs, larvae, and pupari.

Mesopancreas: myth or reality?

PubMed

Agrawal, Manish K; Thakur, Dilip Singh; Somashekar, Uday; Chandrakar, Shiv Kumar; Sharma, Dhananjaya

2010-05-05

A recently published study hypothesized the concept of 'mesopancreas', defining it as a firm, well-vascularized structure extending from the posterior surface of the pancreatic head to behind the mesenteric vessels. To verify and define mesopancreas from resection specimens obtained from fresh cadavers. Postmortem anatomical-pathological study. Department of Surgery in conjunction with the Departments of Forensic Medicine and Pathology, Government Medical College and Hospital, Jabalpur, MP, India. Twenty fresh adult cadavers without any intra-abdominal injury or gross intra-abdominal pathology. Specimens containing the entire duodenum, pancreatic head and neck, gallbladder, cystic duct, common bile duct, superior mesenteric vessels, inferior vena cava and aorta were removed en-bloc. Gross and histopathological examinations of the specimens were carried out. To look for a fibrous sheath or fascia around the retropancreatic structure purported to be a mesopancreas. Loose areolar tissue, adipose tissue, peripheral nerve, nerve plexus, lymphatic and capillaries were found in the retropancreatic tissue, extending from the head, neck and uncinate process of pancreas to the aorto-caval groove but no fibrous sheath or fascia was found around these structures. The concept of 'mesopancreas' is anatomically unfounded.

Benefit of STR-based chimerism analysis to identify TA-GVHD as a cause of death: Utility of various biological specimens.

PubMed

Raina, Anupuma; Chaudhary, Garima; Dogra, Tirath Das; Khandelwal, Deepchand; Balayan, Ajay; Jain, Vandana; Kanga, Uma; Seth, Tulika

2016-04-01

Transfusion-associated graft-versus-host disease (TA-GVHD) is a rare condition. It can occur after blood transfusion in immune-compromised and occasionally even in immune-competent patients, and is associated with a mortality rate of >90%. The diagnosis of TA-GVHD is often delayed because of its non-specific clinical features. A case of an immune-competent child who developed TA-GVHD is reported here. DNA profiling (short tandem repeat analysis), a technique that has a wide application in forensic medicine, was performed to detect the presence of donor cells in this patient. The findings suggest that more studies are needed with this tool, and the diagnostic potential of using other multiple biological specimens for DNA profiling such as the hair follicle and buccal swab should be evaluated. This is the first case report where the donor's DNA fingerprinting pattern was substantiated from a patient's hair follicle sample. Chimerism was also present in the blood and buccal swab specimens. © The Author(s) 2015.

DNA-barcoding of forensically important blow flies (Diptera: Calliphoridae) in the Caribbean Region

PubMed Central

Agnarsson, Ingi

2017-01-01

Correct identification of forensically important insects, such as flies in the family Calliphoridae, is a crucial step for them to be used as evidence in legal investigations. Traditional identification based on morphology has been effective, but has some limitations when it comes to identifying immature stages of certain species. DNA-barcoding, using COI, has demonstrated potential for rapid and accurate identification of Calliphoridae, however, this gene does not reliably distinguish among some recently diverged species, raising questions about its use for delimitation of species of forensic importance. To facilitate DNA based identification of Calliphoridae in the Caribbean we developed a vouchered reference collection from across the region, and a DNA sequence database, and further added the nuclear ITS2 as a second marker to increase accuracy of identification through barcoding. We morphologically identified freshly collected specimens, did phylogenetic analyses and employed several species delimitation methods for a total of 468 individuals representing 19 described species. Our results show that combination of COI + ITS2 genes yields more accurate identification and diagnoses, and better agreement with morphological data, than the mitochondrial barcodes alone. All of our results from independent and concatenated trees and most of the species delimitation methods yield considerably higher diversity estimates than the distance based approach and morphology. Molecular data support at least 24 distinct clades within Calliphoridae in this study, recovering substantial geographic variation for Lucilia eximia, Lucilia retroversa, Lucilia rica and Chloroprocta idioidea, probably indicating several cryptic species. In sum, our study demonstrates the importance of employing a second nuclear marker for barcoding analyses and species delimitation of calliphorids, and the power of molecular data in combination with a complete reference database to enable identification of taxonomically and geographically diverse insects of forensic importance. PMID:28761780

Combining autosomal and Y chromosome match probabilities using coalescent theory.

PubMed

Buckleton, John; Myers, Steven

2014-07-01

Walsh et al. outlined a method for adjusting autosomal coancestry values, θA, to take account of the existence of a Y chromosome match, θA|Y. The framework established by Walsh et al. is flexible and allows an investigation of some real world effects such as family structure. It also allows the effect of a Y chromosome match to be placed within the construct of existing casework practice. Most notable is the ability to deal with an assigned value for the autosomal coancestry coefficient and the fact that most casework statistics report a value for unrelated individuals unless case circumstances suggest differently. The values of θA|Y are not much larger than θA and a coherent argument could be made that any adjustment is unnecessary. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

Investigating drug-facilitated sexual assault at a dedicated forensic centre in Cape Town, South Africa.

PubMed

Tiemensma, Marianne; Davies, Bronwen

2018-04-23

Drug-facilitated sexual assault (DFSA) is a well-recognised public health concern. In South Africa however, epidemiological and toxicological data associated with suspected DFSA are not available. Toxicological screening is currently not routinely available in clinical forensic practice in the Western Cape, or elsewhere in South Africa. To preliminary investigate and characterize DFSA in a specific metropolitan setting in South Africa and to identify the drugs/xenobiotics associated with these reported DFSAs. In total, 107 survivors of suspected DFSA who reported to Victoria Hospital Clinical Forensic Unit in Cape Town, between 1 October 2013 and 30 June 2016, were included. Blood, urine, and/or hair specimens from survivors were screened for drugs of abuse using a targeted LC-MS/MS method. Breath alcohol measurements were conducted using the Dräger Alcotest 6820 after July 2015. Patient, incident and examination history were recorded on standardized data sheets. Of the 107 cases investigated, most of the patients were female (n=104, 97%), between the ages of 18-25years (n=54, 50%), and had reported to the Clinical Forensic Unit within 24h (n=78, 73%). Altogether, 30 patients (28%) reported a history of mental health issues, drugs and/or alcohol use, or prior sexual abuse. Most incidents took place in the late evening/early morning at the home of the assailant(s), a friend or of the patient (n=62, 58%), and most assailants were known to the victim (n=66, 62%). Specimens were positive for drugs and/or ethanol in 72 patients (67%), with drugs other than ethanol being detected in 60 patients (56%). Breath alcohol measurements were conducted in 58 cases during the prospective leg of the study with an average reading of 0.1mg/L (range not detected-0.98mg/L). DFSA in this setting is mostly opportunistic, with ethanol suggested to be the most commonly involved drug, despite limitations in detection due to delays in reporting. Other common drugs observed were methamphetamine, methaqualone and diphenhydramine either alone or in combinations. The complexity and current inadequacy surrounding investigation of these cases is highlighted in this study as well as the necessity for greater investment into the development of infrastructure to support systematic toxicological analyses and services to assist in the investigation and understanding of these intricate cases. Training and empowerment of role players dealing with the investigation and management of DFSA is required, and subsequent public health education and policy development is essential. Copyright © 2018 Elsevier B.V. All rights reserved.

Preventing Child Abuse and Neglect

MedlinePlus

... and Preservation Services Out-of-Home Care National Foster Care Month Overview Foster Care Group and Residential Care Kinship Care Casework ... Adulthood and Independent Living Placement Decisions Resources for Foster Families Achieving & Maintaining Permanency Overview Reunifying Families Recruiting ...

Keys to the blow flies of Taiwan, with a checklist of recorded species and the description of a new species of Paradichosia Senior-White (Diptera, Calliphoridae)

PubMed Central

Yang, Shih-Tsai; Kurahashi, Hiromu; Shiao, Shiuh-Feng

2014-01-01

Abstract Blow flies (Diptera: Calliphoridae) show a great diversity in behavior and ecology, play important roles in ecosystems, and have medical and forensic importance to humans. Despite this, the taxonomy and classification of Taiwan's Calliphoridae have rarely been studied. In this study, specimens of Taiwanese calliphorids were collected and carefully studied, and all 76 species recorded in Taiwan are listed following the identification keys. Dichotomous keys to all subfamilies, tribes, genera, and species of blow flies recorded in Taiwan are provided, including 16 species that are newly recorded from Taiwan. In addition, one new species of the genus Paradichosia Senior-White is described and illustrated. We also discuss the morphological differences between the specimens of Silbomyia hoeneana Enderlein collected from China and Taiwan, a species that has only been found previously in Southern China. PMID:25152681

Investigation of the elastic modulus, tensile and flexural strength of five skull simulant materials for impact testing of a forensic skin/skull/brain model.

PubMed

Falland-Cheung, Lisa; Waddell, J Neil; Chun Li, Kai; Tong, Darryl; Brunton, Paul

2017-04-01

Conducting in vitro research for forensic, impact and injury simulation modelling generally involves the use of a skull simulant with mechanical properties similar to those found in the human skull. For this study epoxy resin, fibre filled epoxy resin, 3D-printing filaments (PETG, PLA) and self-cure acrylic denture base resin were used to fabricate the specimens (n=20 per material group), according to ISO 527-2 IBB and ISO20795-1. Tensile and flexural testing in a universal testing machine was used to measure their tensile/flexural elastic modulus and strength. The results showed that the epoxy resin and fibre filled epoxy resin had similar tensile elastic moduli (no statistical significant difference) with lower values observed for the other materials. The fibre filled epoxy resin had a considerably higher flexural elastic modulus and strength, possibly attributed to the presence of fibres. Of the simulants tested, epoxy resin had an elastic modulus and flexural strength close to that of mean human skull values reported in the literature, and thus can be considered as a suitable skull simulant for a skin/skull/brain model for lower impact forces that do not exceed the fracture stress. For higher impact forces a 3D printing filament (PLA) may be a more suitable skull simulant material, due to its closer match to fracture stresses found in human skull bone. Influencing factors were also anisotropy, heterogeneity and viscoelasticity of human skull bone and simulant specimens. Copyright © 2017 Elsevier Ltd. All rights reserved.

National Foster Care and Adoption Directory Search

MedlinePlus

... Home Topics Family-Centered Practice Philosophy and Key Elements of Family-Centered Practice Family-Centered Practice Across the Service Continuum Engaging Families Family-Centered Casework Practice Family Group Decision-Making Engaging Communities to Support Families Creating a Family- ...

Relationship of risk assessment to placement characteristics in a statewide child welfare population.

PubMed

Huang, Cindy Y; Bory, Christopher T; Caron, Colleen; Tebes, Jacob Kraemer; Connell, Christian M

2014-11-01

Risk assessments allow child and youth services to identify children who are at risk for maltreatment (e.g., abuse, neglect) and help determine the restrictiveness of placements or need for services among youth entering a child welfare system. Despite the use of instruments by many agencies within the U.S. to determine the appropriate placements for youth, research has shown that placement decisions are often influenced by factors such as gender, age, and severity of social-emotional and behavior problems. This study examined ratings of risk across multiple domains using a structured assessment tool used by caseworkers in the Rhode Island child welfare system. The relationship between ratings of risk and placement restrictiveness was also examined. Risk levels varied across placement settings. Multivariate analyses revealed that lower caseworker ratings of parent risk and higher ratings of youth risk were associated with more restrictive placements for youth. Implications for the child welfare system are discussed.

Development of an instrument to understand the child protective services decision-making process, with a focus on placement decisions.

PubMed

Dettlaff, Alan J; Christopher Graham, J; Holzman, Jesse; Baumann, Donald J; Fluke, John D

2015-11-01

When children come to the attention of the child welfare system, they become involved in a decision-making process in which decisions are made that have a significant effect on their future and well-being. The decision to remove children from their families is particularly complex; yet surprisingly little is understood about this decision-making process. This paper presents the results of a study to develop an instrument to explore, at the caseworker level, the context of the removal decision, with the objective of understanding the influence of the individual and organizational factors on this decision, drawing from the Decision Making Ecology as the underlying rationale for obtaining the measures. The instrument was based on the development of decision-making scales used in prior decision-making studies and administered to child protection caseworkers in several states. Analyses included reliability analyses, principal components analyses, and inter-correlations among the resulting scales. For one scale regarding removal decisions, a principal components analysis resulted in the extraction of two components, jointly identified as caseworkers' decision-making orientation, described as (1) an internal reference to decision-making and (2) an external reference to decision-making. Reliability analyses demonstrated acceptable to high internal consistency for 9 of the 11 scales. Full details of the reliability analyses, principal components analyses, and inter-correlations among the seven scales are discussed, along with implications for practice and the utility of this instrument to support the understanding of decision-making in child welfare. Copyright © 2015 Elsevier Ltd. All rights reserved.

Systematic study for DNA recovery and profiling from common IED substrates: From laboratory to casework.

PubMed

Phetpeng, Sukanya; Kitpipit, Thitika; Thanakiatkrai, Phuvadol

2015-07-01

Improvised explosive devices (IEDs) made from household items are encountered in terrorist attacks worldwide. Assembling an IED leaves trace DNA on its components, but deflagration degrades DNA. To maximize the amount of DNA recovered, a systematic evaluation of DNA collection methods was carried out and the most efficient methods were implemented with IED casework evidence as a validation exercise. Six swab types and six moistening agents were used to collect dried buffy coat stains on four common IED substrates. The most efficient swab/moistening agent combinations were then compared with tape-lifting using three brands of adhesive tape and also with direct DNA extraction from evidence. The most efficient collection methods for different IED substrates (post-study protocol) were then implemented for IED casework and compared with the pre-study protocol using 195 pieces of IED evidence. There was no single best swab type or moistening agent. Swab type had the largest effect on DNA recovery percentages, but moistening agents, substrates, and the interactions between factors all affected DNA recovery. The most efficient swab/moistening agent combinations performed equally well when compared with the best adhesive tape and direct extraction. The post-study protocol significantly improved STR profiles obtained from IED evidence. This paper outlines a comprehensive study of DNA collection methods for trace DNA and the validation of the most efficient collection methods with IED evidence. The findings from both parts of this study emphasize the need to continuously re-evaluate standard operating protocols with empirical studies. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

77 FR 27071 - Submission for OMB Review; Comment Request

Federal Register 2010, 2011, 2012, 2013, 2014

2012-05-08

...: Families (parents, or permanent or foster caregivers; children), caseworkers, supervisors, service... DEPARTMENT OF HEALTH AND HUMAN SERVICES Administration for Children and Families Submission for....: New Collection. Description: The Administration for Children and Families (ACF), U.S. Department of...

Direct PCR amplification of DNA from human bloodstains, saliva, and touch samples collected with microFLOQ® swabs.

PubMed

Ambers, Angie; Wiley, Rachel; Novroski, Nicole; Budowle, Bruce

2018-01-01

Previous studies have shown that nylon flocked swabs outperform traditional fiber swabs in DNA recovery due to their innovative design and lack of internal absorbent core to entrap cellular materials. The microFLOQ ® Direct swab, a miniaturized version of the 4N6 FLOQSwab ® , has a small swab head that is treated with a lysing agent which allows for direct amplification and DNA profiling from sample collection to final result in less than two hours. Additionally, the microFLOQ ® system subsamples only a minute portion of a stain and preserves the vast majority of the sample for subsequent testing or re-analysis, if desired. The efficacy of direct amplification of DNA from dilute bloodstains, saliva stains, and touch samples was evaluated using microFLOQ ® Direct swabs and the GlobalFiler™ Express system. Comparisons were made to traditional methods to assess the robustness of this alternate workflow. Controlled studies with 1:19 and 1:99 dilutions of bloodstains and saliva stains consistently yielded higher STR peak heights than standard methods with 1ng input DNA from the same samples. Touch samples from common items yielded single source and mixed profiles that were consistent with primary users of the objects. With this novel methodology/workflow, no sample loss occurs and therefore more template DNA is available during amplification. This approach may have important implications for analysis of low quantity and/or degraded samples that plague forensic casework. Copyright © 2017 The Authors. Published by Elsevier B.V. All rights reserved.

Validation of a combined autosomal/Y-chromosomal STR approach for analyzing typical biological stains in sexual-assault cases.

PubMed

Purps, Josephine; Geppert, Maria; Nagy, Marion; Roewer, Lutz

2015-11-01

DNA testing is an established part of the investigation and prosecution of sexual assault. The primary purpose of DNA evidence is to identify a suspect and/or to demonstrate sexual contact. However, due to highly uneven proportions of female and male DNA in typical stains, routine autosomal analysis often fails to detect the DNA of the assailant. To evaluate the forensic efficiency of the combined application of autosomal and Y-chromosomal short tandem repeat (STR) markers, we present a large retrospective casework study of probative evidence collected in sexual-assault cases. We investigated up to 39 STR markers by testing combinations of the 16-locus NGMSElect kit with both the 23-locus PowerPlex Y23 and the 17-locus Yfiler kit. Using this dual approach we analyzed DNA extracts from 2077 biological stains collected in 287 cases over 30 months. To assess the outcome of the combined approach in comparison to stand-alone autosomal analysis we evaluated informative DNA profiles. Our investigation revealed that Y-STR analysis added up to 21% additional, highly informative (complete, single-source) profiles to the set of reportable autosomal STR profiles for typical stains collected in sexual-assault cases. Detection of multiple male contributors was approximately three times more likely with Y-chromosomal profiling than with autosomal STR profiling. In summary, 1/10 cases would have remained inconclusive (and could have been dismissed) if Y-STR analysis had been omitted from DNA profiling in sexual-assault cases. Copyright © 2015 The Authors. Published by Elsevier Ireland Ltd.. All rights reserved.

Age estimation standards for a Western Australian population using the coronal pulp cavity index.

PubMed

Karkhanis, Shalmira; Mack, Peter; Franklin, Daniel

2013-09-10

Age estimation is a vital aspect in creating a biological profile and aids investigators by narrowing down potentially matching identities from the available pool. In addition to routine casework, in the present global political scenario, age estimation in living individuals is required in cases of refugees, asylum seekers, human trafficking and to ascertain age of criminal responsibility. Thus robust methods that are simple, non-invasive and ethically viable are required. The aim of the present study is, therefore, to test the reliability and applicability of the coronal pulp cavity index method, for the purpose of developing age estimation standards for an adult Western Australian population. A total of 450 orthopantomograms (220 females and 230 males) of Australian individuals were analyzed. Crown and coronal pulp chamber heights were measured in the mandibular left and right premolars, and the first and second molars. These measurements were then used to calculate the tooth coronal index. Data was analyzed using paired sample t-tests to assess bilateral asymmetry followed by simple linear and multiple regressions to develop age estimation models. The most accurate age estimation based on simple linear regression model was with mandibular right first molar (SEE ±8.271 years). Multiple regression models improved age prediction accuracy considerably and the most accurate model was with bilateral first and second molars (SEE ±6.692 years). This study represents the first investigation of this method in a Western Australian population and our results indicate that the method is suitable for forensic application. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

DNA methylation-based variation between human populations.

PubMed

Kader, Farzeen; Ghai, Meenu

2017-02-01

Several studies have proved that DNA methylation affects regulation of gene expression and development. Epigenome-wide studies have reported variation in methylation patterns between populations, including Caucasians, non-Caucasians (Blacks), Hispanics, Arabs, and numerous populations of the African continent. Not only has DNA methylation differences shown to impact externally visible characteristics, but is also a potential biomarker for underlying racial health disparities between human populations. Ethnicity-related methylation differences set their mark during early embryonic development. Genetic variations, such as single-nucleotide polymorphisms and environmental factors, such as age, dietary folate, socioeconomic status, and smoking, impacts DNA methylation levels, which reciprocally impacts expression of phenotypes. Studies show that it is necessary to address these external influences when attempting to differentiate between populations since the relative impacts of these factors on the human methylome remain uncertain. The present review summarises several reported attempts to establish the contribution of differential DNA methylation to natural human variation, and shows that DNA methylation could represent new opportunities for risk stratification and prevention of several diseases amongst populations world-wide. Variation of methylation patterns between human populations is an exciting prospect which inspires further valuable research to apply the concept in routine medical and forensic casework. However, trans-generational inheritance needs to be quantified to decipher the proportion of variation contributed by DNA methylation. The future holds thorough evaluation of the epigenome to understand quantification, heritability, and the effect of DNA methylation on phenotypes. In addition, methylation profiling of the same ethnic groups across geographical locations will shed light on conserved methylation differences in populations.

Persistence of immersed blood and hair DNA: A preliminary study based on casework.

PubMed

Frippiat, Christophe; Gastaldi, Agathe; Van Grunderbeeck, Séverine

2017-10-01

In some cases, evidence is collected from rivers, canals, lakes or sink pipes. To determine the utility of analyzing these samples and for cases in which DNA was recovered from submerged bulletproof vest parts, we evaluated the time necessary to degrade the blood and, subsequently, DNA on bulletproof vests. In a second experiment, also based on cases, blood was diluted in water from a kitchen sink pipe and incubated at room temperature for different times. Subsequently, DNA quality was assessed. In a parallel experiment, hair roots were incubated in spring water for different time periods. This study demonstrates that after one week of immersion of the bulletproof vest parts in a canal only one sample from more than 100 samples gave a partial genetic profile. No genetic profile were obtained for the 99 other samples. After one month immersion and despite the finding that blood remained detectable on bulletproof vest parts, no genetic profile was obtained for all samples using the classical STR approach. For longer immersion times, no genetic profiles were obtained. In sink pipe water, an incubation time of 72 h (h) was necessary before significant blood degradation occurred. Nevertheless, high inter-sample variability was observed. This high variability may be explained by the variability of water composition coming from nine different sink pipes. For hair root cells incubated in water, we observed that more than 90% of the DNA was degraded after 72 h. Copyright © 2017 Elsevier Ltd and Faculty of Forensic and Legal Medicine. All rights reserved.

[Correlates of mental health in Japanese caseworkers employed at social welfare offices].

PubMed

Akama, Yumi; Morikagi, Yuko; Ohtake, Mariko; Suzuki, Ikuko; Kanoya, Yuka; Hosoya, Takiko; Kobayashi, Atsuko

2014-01-01

The aim of this study was to evaluate the correlation between the mental health status of caseworkers at welfare offices and factors affecting mental health (i.e., working conditions, participation in training courses and workshops, lifestyle habits, presence of illness, social support, and self-efficacy). The welfare offices in Japan (1,230 locations) were arranged in descending order according to their establishment and region. Systematic sampling was then conducted to select 20% (n =246) of the welfare institutions for this study. A total of 1,230 caseworkers on welfare (five from each institution) were administered anonymous self-completed questionnaires. The questionnaires involved the General Health Questionnaire (GHQ)-28 Japanese version and questions regarding basic attributes, working conditions, social support (i.e., family, friends, superiors, and colleagues), participation in training courses and workshops, presence of illness, lifestyle habits, mental health, and self-efficacy. Subjects were divided into the following 2 groups: low-score group (GHQ-28 score ≤5) and high-score group (GHQ-28 score ≥6). Data were analyzed using a t-test, χ(2) test, and Fisher's exact test. The GHQ-28 high- and low-score groups were considered gender-specific dependent variables due to the sex differences observed in the univariate analysis. Significant variables in the univariate analysis were considered independent variables in the multiple logistic regression analysis (forward stepwise selection). Five hundred and six people (410 male and 96 female) provided valid responses. Most respondents had poor mental health (66%, high-score group; 34%, low-score group). Both men and women who worked ≥10 hours/day had significantly poorer mental health than individuals who worked ≤9 hours/day. Individuals with low self-efficacy had significantly poorer mental health compared to people with high self-efficacy. Men who were able to maintain moderate hours of sleep and received support from colleagues, friends, and family had good mental health. Among women, mental health deteriorated with age. Furthermore, women who devoted most work time to home visit had good mental health. The mental health of caseworkers at welfare offices can be improved by reducing overtime work hours, ensuring sufficient hours of sleep for each worker, and fostering supportive communication and self-efficacy in the workplace. Furthermore, sex differences should be considered when assessing the mental health of workers at welfare offices in Japan.

Scanning electron microscope analysis of gunshot defects to bone: an underutilized source of information on ballistic trauma.

PubMed

Rickman, John M; Smith, Martin J

2014-11-01

Recent years have seen increasing involvement by forensic anthropologists in the interpretation of skeletal trauma. With regard to ballistic injuries, there is now a large literature detailing gross features of such trauma; however, less attention has been given to microscopic characteristics. This article presents analysis of experimentally induced gunshot trauma in animal bone (Bos taurus scapulae) using full metal jacket (FMJ), soft point (SP), and captive bolt projectiles. The results were examined using scanning electron microscopy (SEM). Additional analysis was conducted on a purported parietal gunshot lesion in a human cranial specimen. A range of features was observed in these samples suggesting that fibrolamellar bone response to projectile impact is analogous to that observed in synthetic composite laminates. The results indicate that direction of bullet travel can be discerned microscopically even when it is ambiguous on gross examination. It was also possible to distinguish SP from FMJ lesions. SEM analysis is therefore recommended as a previously underexploited tool in the analysis of ballistic trauma. © 2014 American Academy of Forensic Sciences.

Evolution of the content of THC and other major cannabinoids in drug-type cannabis cuttings and seedlings during growth of plants.

PubMed

De Backer, Benjamin; Maebe, Kevin; Verstraete, Alain G; Charlier, Corinne

2012-07-01

In Europe, authorities frequently ask forensic laboratories to analyze seized cannabis plants to prove that cultivation was illegal (drug type and not fiber type). This is generally done with mature and flowering plants. However, authorities are often confronted with very young specimens. The aim of our study was to evaluate when the chemotype of cannabis plantlets can be surely determined through analysis of eight major cannabinoids content during growth. Drug-type seedlings and cuttings were cultivated, sampled each week, and analyzed by high-performance liquid chromatography with diode array detection. The chemotype of clones was recognizable at any developmental stage because of high total Δ(9)-tetrahydrocannabinol (THC) concentrations even at the start of the cultivation. Conversely, right after germination seedlings contained a low total THC content, but it increased quickly with plant age up, allowing chemotype determination after 3 weeks. In conclusion, it is not necessary to wait for plants' flowering to identify drug-type cannabis generally cultivated in Europe. © 2012 American Academy of Forensic Sciences.

Gender differences in D-aspartic acid content in skull bone.

PubMed

Torikoshi-Hatano, Aiko; Namera, Akira; Shiraishi, Hiroaki; Arima, Yousuke; Toubou, Hirokazu; Ezaki, Jiro; Morikawa, Masami; Nagao, Masataka

2012-12-01

In forensic medicine, the personal identification of cadavers is one of the most important tasks. One method of estimating age at death relies on the high correlation between racemization rates in teeth and actual age, and this method has been applied successfully in forensic odontology for several years. In this study, we attempt to facilitate the analysis of racemized amino acids and examine the determination of age at death on the basis of the extent of aspartic acid (Asp) racemization in skull bones. The specimens were obtained from 61 human skull bones (19 females and 42 males) that underwent judicial autopsy from October 2010 to May 2012. The amount of D-Asp and L-Asp, total protein, osteocalcin, and collagen I in the skull bones was measured. Logistic regression analysis was performed for age, sex, and each measured protein. The amount of D-Asp in the female skull bones was significantly different from that in the male skull bones (p = 0.021), whereas the amount of L-Asp was similar. Thus, our study indicates that the amount of D-Asp in skull bones is different between the sexes.

Good Practices in Forensic Toxicology.

PubMed

Drummer, Olaf H

2017-01-01

This manuscript provides an overview for analysts, medical and scientific investigators, and laboratory administrators, the range of factors that should be considered to implement best practice forensic toxicology. These include laboratory influence over the collection of specimens, their proper transport and chain-of-custody before arrival in the laboratory. In addition, the laboratory needs to ensure properly trained staff use suitably validated and documented analytical procedures that meet the intended purpose and type of case in an accredited or suitably quality oriented management system. To assist the investigating officers laboratory results require an interpretation over their possible significance when sufficient details are available over the circumstances of the case. This requires a thorough understanding of the various factors that influence concentrations of substances and ultimately their likely physiological effect. These include consideration of the route of ingestion, influence over chronicity of usage on tissue concentrations and tolerance, possible combined drug effects or likely adverse reactions and consideration of relevant genetic factors that may have influenced pharmacokinetic or pharmacodynamic response. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

Insects found on a human cadaver in central Italy including the blowfly Calliphora loewi (Diptera, Calliphoridae), a new species of forensic interest.

PubMed

Vanin, S; Gherardi, M; Bugelli, V; Di Paolo, M

2011-04-15

In the case of unidentified bodies the estimation of the period since death or of the season of death plays an important role to focus the attention on a reduced number of people among the ones reported missing. Forensic entomology can be one of the most important methods for these estimations, as occurred in this case. Flies are typically the first insects to colonize a dead body. The case reported here concerns the colonisation by insects of a male body in advanced decay found during the winter in Central Italy. This case is of particular interest as few data are available on the entomological evidence in the cold season. In particular, in this case we recovered Calliphora loewi (Calliphoridae), a species never collected before on dead bodies in Southern Europe. Larvae of the black soldier fly Hermetia illucens (Stratiomyidae), pupae and larvae belonging to genus Hydrothea (Muscidae), and Necrobia rufipes (Cleridae) specimens were also collected. The estimated PMI enabled identification of the cadaver, confirmed by DNA analysis. Copyright © 2010 Elsevier Ireland Ltd. All rights reserved.

A Rapid and Inexpensive PCR-Based STR Genotyping Method for Identifying Forensic Specimens

DTIC Science & Technology

2006-06-01

this report) 20. Security Classif. (of this page) 21 . No. of Pages 22. Price Unclassified Unclassified 18 Form DOT F 1700.7 (8-72) Reproduction of...Promega PowerPlex 2.1 system (7) except that the buffer was 1x Amplitaq gold reaction buffer, 0.1% TritonX-100, and 0.2mM each dNTP in a 25µl final...electrophoresis were done using the PowerPlex 16 System (Promega Corp.; Madison, WI). rEsulTs ANd dIsCussION The goal of this study was to develop a simple DNA

Forensic toxicology.

PubMed

Drummer, Olaf H

2010-01-01

Forensic toxicology has developed as a forensic science in recent years and is now widely used to assist in death investigations, in civil and criminal matters involving drug use, in drugs of abuse testing in correctional settings and custodial medicine, in road and workplace safety, in matters involving environmental pollution, as well as in sports doping. Drugs most commonly targeted include amphetamines, benzodiazepines, cannabis, cocaine and the opiates, but can be any other illicit substance or almost any over-the-counter or prescribed drug, as well as poisons available to the community. The discipline requires high level skills in analytical techniques with a solid knowledge of pharmacology and pharmacokinetics. Modern techniques rely heavily on immunoassay screening analyses and mass spectrometry (MS) for confirmatory analyses using either high-performance liquid chromatography or gas chromatography as the separation technique. Tandem MS has become more and more popular compared to single-stage MS. It is essential that analytical systems are fully validated and fit for the purpose and the assay batches are monitored with quality controls. External proficiency programs monitor both the assay and the personnel performing the work. For a laboratory to perform optimally, it is vital that the circumstances and context of the case are known and the laboratory understands the limitations of the analytical systems used, including drug stability. Drugs and poisons can change concentration postmortem due to poor or unequal quality of blood and other specimens, anaerobic metabolism and redistribution. The latter provides the largest handicap in the interpretation of postmortem results.

[Dipterans of forensic interest in two vegetation profiles of cerrado in Uberlândia, State of Minas Gerais, Brazil].

PubMed

Rosa, Thiago A; Babata, Micaela L Y; De Souza, Carina M; De Sousa, Danielle; De Mello-Patiu, Cátia A; Mendes, Júlio

2009-01-01

Carrion breeding insects may be of great utility in crimes briefing. Studies on forensic entomology are restricted to few localities in Brazil and very few of them were done in the cerrado vegetation (a type of Savannah) until now. This work aimed to survey the main species of dipterans associated with the decomposition process of Sus scrofa and the insect succession pattern in carcasses in the Cerrado. The study was carried out in the dry and humid season of the year, in two cerrado vegetation profiles in Uberlândia, MG. Two pig carcasses were placed in each vegetation profile and time period of the year. The decomposition process was slower and insects were more abundant in the dry season. Differences in temperature, air humidity and pluvial precipitation seemed to be the main physical factors responsible for the differences in the time of decomposition of the pig carcasses between the two seasons. Fourteen species of dipterans (59,467 specimens) bred in the decomposing carcasses. Chrysomya albiceps (Wiedemann) was the species more abundantly breed in the two periods. The other species that breed in the carcasses were: C. putoria (Wiedemann), Hemilucilia segmentaria(Fabricius), Lucilia eximia(Wiedemann) (Calliphoridae), Peckia (Pattonella) intermutans(Walker), Peckia (Squamatoides) trivitatta(Curran), Sarcodexia lambens(Wiedemann) (Sarcophagidae), Musca domestica(L.), Ophyra aenescens(Wiedemann), Stomoxys calcitransL. (Muscidae), Fannia pusio(Wiedemann), Fannia sp. (Fanniidae), Hermetia illuscens L. (Stratiomyidae) and Phoridae sp. The Cerrado of this region presents many dipterans potential forensic indicators.

Tissue Microarray Analysis Applied to Bone Diagenesis

PubMed Central

Mello, Rafael Barrios; Silva, Maria Regina Regis; Alves, Maria Teresa Seixas; Evison, Martin Paul; Guimarães, Marco Aurelio; Francisco, Rafaella Arrabaca; Astolphi, Rafael Dias; Iwamura, Edna Sadayo Miazato

2017-01-01

Taphonomic processes affecting bone post mortem are important in forensic, archaeological and palaeontological investigations. In this study, the application of tissue microarray (TMA) analysis to a sample of femoral bone specimens from 20 exhumed individuals of known period of burial and age at death is described. TMA allows multiplexing of subsamples, permitting standardized comparative analysis of adjacent sections in 3-D and of representative cross-sections of a large number of specimens. Standard hematoxylin and eosin, periodic acid-Schiff and silver methenamine, and picrosirius red staining, and CD31 and CD34 immunohistochemistry were applied to TMA sections. Osteocyte and osteocyte lacuna counts, percent bone matrix loss, and fungal spheroid element counts could be measured and collagen fibre bundles observed in all specimens. Decalcification with 7% nitric acid proceeded more rapidly than with 0.5 M EDTA and may offer better preservation of histological and cellular structure. No endothelial cells could be detected using CD31 and CD34 immunohistochemistry. Correlation between osteocytes per lacuna and age at death may reflect reported age-related responses to microdamage. Methodological limitations and caveats, and results of the TMA analysis of post mortem diagenesis in bone are discussed, and implications for DNA survival and recovery considered. PMID:28051148

Forensic toxicology.

PubMed

Davis, Gregory G

2012-01-01

Toxicologic analysis is an integral part of death investigation, and the use or abuse of an unsuspected substance belongs in the differential diagnosis of patients who have a sudden, unexpected change in their condition. History and physical findings may alter suspicion that intoxication played a role in a patient's decline or death, but suspicions cannot be confirmed and is performed, analysis unless toxicologic no toxicologic analysis is possible unless someone collects the proper specimens necessary for analysis. In a hospital autopsy the only specimens that can rightfully be collected are those within the restrictions stated in the autopsy permit. Autopsies performed by the medical examiner do not have these restrictions. Sometimes the importance of toxicologic testing in a case is not evident until days or weeks after the change in the patient's status, thus retaining the appropriate specimens until investigation of that case has ended is important. Proper interpretation of toxicologic findings requires integrating the clinical setting and findings with the toxicologic results in a way that makes medical sense. If called upon to testify concerning findings, answer the questions truthfully, politely, and in a way that is understandable to someone who has no special training in toxicology.

Utilization of Offender Case Information by "Lenient" vs. "Punitive" Clinicians

ERIC Educational Resources Information Center

Holland, Terrill R.; Holt, Norman

1978-01-01

Presentence evaluations conducted by psychologists and psychiatrists (clinicians) and correctional counselors (caseworkers) were subjected to multiple regression analyses in order to specify the relative contribution of inmate characteristics (offense severity and recidivism probability) and decision-maker response biases to sentencing…

(210)Po poisoning as possible cause of death: forensic investigations and toxicological analysis of the remains of Yasser Arafat.

PubMed

Froidevaux, Pascal; Bochud, François; Baechler, Sébastien; Castella, Vincent; Augsburger, Marc; Bailat, Claude; Michaud, Katarzyna; Straub, Marietta; Pecchia, Marco; Jenk, Theo M; Uldin, Tanya; Mangin, Patrice

2016-02-01

The late president of the Palestinian Authority, Yasser Arafat, died in November 2004 in Percy Hospital, one month after having experienced a sudden onset of symptoms that included severe nausea, vomiting, diarrhoea and abdominal pain and which were followed by multiple organ failure. In spite of numerous investigations performed in France, the pathophysiological mechanisms at the origin of the symptoms could not be identified. In 2011, we found abnormal levels of polonium-210 ((210)Po) in some of Arafat's belongings that were worn during his final hospital stay and which were stained with biological fluids. This finding led to the exhumation of Arafat's remains in 2012. Significantly higher (up to 20 times) activities of (210)Po and lead-210 ((210)Pb) were found in the ribs, iliac crest and sternum specimens compared to reference samples from the literature (p-value <1%). In all specimens from the tomb, (210)Po activity was supported by a similar activity of (210)Pb. Biokinetic calculations demonstrated that a (210)Pb impurity, as identified in a commercial source of 3MBq of (210)Po, may be responsible for the activities measured in Arafat's belongings and remains 8 years after his death. The absence of myelosuppression and hair loss in Mr Arafat's case compared to Mr Litvinenko's, the only known case of malicious poisoning with (210)Po, could be explained by differences in the time delivery-scheme of intake. In conclusion, statistical Bayesian analysis combining all the evidence gathered in our forensic expert report moderately supports the proposition that Mr Arafat was poisoned by (210)Po. Copyright © 2015 The Authors. Published by Elsevier Ireland Ltd.. All rights reserved.

Determination of 32 cathinone derivatives and other designer drugs in serum by comprehensive LC-QQQ-MS/MS analysis.

PubMed

Swortwood, Madeleine J; Boland, Diane M; DeCaprio, Anthony P

2013-02-01

Recently, clandestine drug lab operators have attempted to bypass controlled substances laws and regulations with "designer" compounds chemically and pharmacologically similar to controlled substances. For example, "bath salts" have erupted onto the scene as "legal highs" containing cathinone analogs that have produced severe side effects in users worldwide. These products have sparked concern among law enforcement agencies, and emergency bans have been placed on the sale of such items. Despite the increasing number of designer drugs available, there are few comprehensive screening techniques for their detection and quantification in biological specimens. The liquid chromatography triple quadrupole tandem mass spectrometry (LC-QQQ-MS/MS) method presented here encompasses over thirty important compounds within the phenethylamine, tryptamine, and piperazine designer drug classes. Analytes were determined by LC-QQQ-MS/MS in the multiple-reaction monitoring mode after mixed-mode solid-phase extraction. The bioanalytical method was fully validated according to recommended international guidelines. The assay was selective for all analytes with acceptable accuracy and precision. Limits of quantification were in the range of 1-10 ng/mL for each compound with limits of detection near 10 pg/mL. In order to evaluate its applicability in a forensic toxicological setting, the validated method was used to analyze post-mortem specimens from two cases that were suspected of containing designer drugs. The method was able to identify and quantify seven of these compounds at concentrations as low as 11 ng/mL. The method should have wide applicability for rapid screening of important new drugs of abuse at high sensitivity in both post- and ante-mortem forensic analysis.

Ultrastructure of preimaginal stages of Piophila megastigmata McAlpine, 1978 (Diptera, Piophilidae): a fly of forensic importance.

PubMed

Paños, A; Arnaldos, M I; García, M D; Ubero-Pascal, N

2013-11-01

Piophila Fallén, 1810 is a genus of small flies composed of two species: Piophila casei (P. casei ) (Linnaeus, 1758), worldwide distributed, and Piophila megastigmata (P. megastigmata ) McAlpine, 1978, recently referred in the Palaearctic Region, from the Iberian Peninsula. Both species share ecological niche and are very interesting for forensic purposes, since they are present in carrion in advance stages of decay and have been found to be related to human corpses. The immature stages of P. megastigmata have ever been described, so this paper gives the ultrastructural morphologies of all preimaginal stages of P. megastigmata studied by light microscopy and scanning electron microscopy (SEM). Particular attention is given to pseudocephalon features—antenna, maxillary palps, facial mask, etc.—cephalopharyngeal skeleton, anterior and posterior spiracles, tegumentary sculpturing, and anal division among others. A comparative analysis of the main distinguishing features is made in order to understand how those features evolve along the developmental process, while larvae II and III are morphologically similar to each other, the larva I shows particular features. Larvae of all stages and pupae are easily distinguishable from other Diptera of forensic importance just based on the presence of trichoid sensilla associated to respiratory slits, instead of peristigmatig tufts, as well as on thewell-known disposition of anal papillae. The shapes of both dorsal edge at the basal part of mouthhook and dorsal bridge of cephalopharyngeal skeleton, and the tegumental ornamentationmay be considered as good features to distinguish the Piophila species, especially for P. megastigmata and P. casei . At the SEM level, shape, number, and arrangement of oral combs, oral ridges, sensilla of maxillary palpus, papillae of anterior spiracle, scales of spiracular field, and posterior spiracles represent good features to distinguish P. megastigmata from P. casei, but further studies will be necessary in West-Paleartic specimens of latter species. The key for identifying third instar larvae of forensically important Piophilidae in the Iberian Peninsula has been updated to include P. megastigmata.

Comprehensive Family Services and Customer Satisfaction Outcomes

ERIC Educational Resources Information Center

Huebner, Ruth A.; Jones, Blake L.; Miller, Viola P.; Custer, Melba; Critchfield, Becky

2006-01-01

Comprehensive Family Services (CFS) is a strengths-based and partnership-oriented approach to casework implemented through multiple initiatives. This study examines the relationship between the practice of CFS and satisfaction of clients, foster parents, and community partners. CFS indicators are paired with statewide customer satisfaction survey…

The benefits of motivational interviewing and coaching for improving the practice of comprehensive family assessments in child welfare.

PubMed

Snyder, Elizabeth H; Lawrence, C Nicole; Weatherholt, Tara N; Nagy, Paul

2012-01-01

The engagement of families in child welfare services is critical for successful outcomes related to safety, permanency, and child and family well-being. Motivational interviewing (MI), an effective approach to working with individuals struggling with alcohol and drug addiction, has great appeal for use with families involved with the child welfare system. Consequently, many social service agencies are beginning to integrate MI into their training curriculum. However, research has shown that training in MI alone is not enough; ongoing coaching is crucial in order to transfer learned MI skills into practice.The current study employs qualitative interview data from case-workers in order to examine the implementation of MI and long-term coaching within the child welfare system. Findings showed that MI can be implemented successfully within the child welfare system, and that caseworkers believed MI, supported by ongoing coaching, to be a valuable tool in engaging families in the assessment process.

Examining internal and external job resources in child welfare: Protecting against caseworker burnout.

PubMed

He, Amy S; Phillips, Jon D; Lizano, Erica L; Rienks, Shauna; Leake, Robin

2018-07-01

Given intense job demands, it is not surprising that job burnout is a consistent threat to the well-being and retention of the child welfare workforce. Guided by central postulates of the Job Demands and Resources (JD-R) model which suggests that job burnout develops because of experiences of high work demands coupled with low resources in the workplace, we applied a conceptual model of job burnout (client and work related) that accounts for both internal and external resources available to child welfare workers. Findings among child welfare caseworkers from three states (N = 1917) indicate that job demands (stress and time pressure) were positively related to client- and work-related burnout. Additionally, both internal and external resources moderated the relationships between job demands and client- and work-related burnout. Study findings have workforce management implications in the child welfare sector, including the role resources might play in mitigating the negative impact of job demands on burnout in the child welfare workforce. Copyright © 2018 Elsevier Ltd. All rights reserved.

Challenges in using medicaid claims to ascertain child maltreatment.

PubMed

Raghavan, Ramesh; Brown, Derek S; Allaire, Benjamin T; Garfield, Lauren D; Ross, Raven E; Hedeker, Donald

2015-05-01

Medicaid data contain International Classification of Diseases, Clinical Modification (ICD-9-CM) codes indicating maltreatment, yet there is a little information on how valid these codes are for the purposes of identifying maltreatment from health, as opposed to child welfare, data. This study assessed the validity of Medicaid codes in identifying maltreatment. Participants (n = 2,136) in the first National Survey of Child and Adolescent Well-Being were linked to their Medicaid claims obtained from 36 states. Caseworker determinations of maltreatment were compared with eight sets of ICD-9-CM codes. Of the 1,921 children identified by caseworkers as being maltreated, 15.2% had any relevant ICD-9-CM code in any of their Medicaid files across 4 years of observation. Maltreated boys and those of African American race had lower odds of displaying a maltreatment code. Using only Medicaid claims to identify maltreated children creates validity problems. Medicaid data linkage with other types of administrative data is required to better identify maltreated children. © The Author(s) 2014.

How do abused elderly persons and their adult protective services caseworkers view law enforcement involvement and criminal prosecution, and what impact do these views have on case processing?

PubMed

Jackson, Shelly L; Hafemeister, Thomas L

2013-01-01

This study examined law enforcement and prosecution involvement in 71 cases of elder abuse where pure financial exploitation (PFE), physical abuse (PA), neglect (Neglect), or hybrid financial exploitation (HFE) (financial exploitation co-occurring with physical abuse and/or neglect) occurred in a domestic setting. Victims of elder abuse and assigned Adult Protective Services (APS) caseworkers were systematically interviewed. Law enforcement officials were involved in 54% of the cases, and 18% of the cases were prosecuted. PA was significantly more likely to trigger a law enforcement response and to be prosecuted than Neglect or PFE. HFE involved prosecution for assault rather than financial exploitation. Generally, the victims of elder abuse were not receptive to criminal justice involvement, which appears to have a significant impact upon the level of this involvement. The reasons for this reluctance are discussed, as well as the challenges and limitations of criminal justice system involvement and related implications for policy and practice.

Evaluation of different sources of DNA for use in genome wide studies and forensic application.

PubMed

Al Safar, Habiba S; Abidi, Fatima H; Khazanehdari, Kamal A; Dadour, Ian R; Tay, Guan K

2011-02-01

In the field of epidemiology, Genome-Wide Association Studies (GWAS) are commonly used to identify genetic predispositions of many human diseases. Large repositories housing biological specimens for clinical and genetic investigations have been established to store material and data for these studies. The logistics of specimen collection and sample storage can be onerous, and new strategies have to be explored. This study examines three different DNA sources (namely, degraded genomic DNA, amplified degraded genomic DNA and amplified extracted DNA from FTA card) for GWAS using the Illumina platform. No significant difference in call rate was detected between amplified degraded genomic DNA extracted from whole blood and amplified DNA retrieved from FTA™ cards. However, using unamplified-degraded genomic DNA reduced the call rate to a mean of 42.6% compared to amplified DNA extracted from FTA card (mean of 96.6%). This study establishes the utility of FTA™ cards as a viable storage matrix for cells from which DNA can be extracted to perform GWAS analysis.

Ballistics projectile image analysis for firearm identification.

PubMed

Li, Dongguang

2006-10-01

This paper is based upon the observation that, when a bullet is fired, it creates characteristic markings on the cartridge case and projectile. From these markings, over 30 different features can be distinguished, which, in combination, produce a "fingerprint" for a firearm. By analyzing features within such a set of firearm fingerprints, it will be possible to identify not only the type and model of a firearm, but also each and every individual weapon just as effectively as human fingerprint identification. A new analytic system based on the fast Fourier transform for identifying projectile specimens by the line-scan imaging technique is proposed in this paper. This paper develops optical, photonic, and mechanical techniques to map the topography of the surfaces of forensic projectiles for the purpose of identification. Experiments discussed in this paper are performed on images acquired from 16 various weapons. Experimental results show that the proposed system can be used for firearm identification efficiently and precisely through digitizing and analyzing the fired projectiles specimens.

Assessing Impact Direction in 3-point Bending of Human Femora: Incomplete Butterfly Fractures and Fracture Surfaces,.

PubMed

Isa, Mariyam I; Fenton, Todd W; Deland, Trevor; Haut, Roger C

2018-01-01

Current literature associates bending failure with butterfly fracture, in which fracture initiates transversely at the tensile surface of a bent bone and branches as it propagates toward the impact surface. The orientation of the resulting wedge fragment is often considered diagnostic of impact direction. However, experimental studies indicate bending does not always produce complete butterfly fractures or produces wedge fragments variably in tension or compression, precluding their use in interpreting directionality. This study reports results of experimental 3-point bending tests on thirteen unembalmed human femora. Complete fracture patterns varied following bending failure, but incomplete fractures and fracture surface characteristics were observed in all impacted specimens. A flat, billowy fracture surface was observed in tension, while jagged, angular peaks were observed in compression. Impact direction was accurately reconstructed using incomplete tension wedge butterfly fractures and tension and compression fracture surface criteria in all thirteen specimens. © 2017 American Academy of Forensic Sciences.

A new species of Oxelytrum Gistel (Coleoptera, Silphidae) from southern Argentina, with a key to the species of the genus

PubMed Central

Oliva, Adriana

2012-01-01

Abstract A new species of the forensically interesting genus Oxelytrum Gistel (Coleoptera, Silphidae), Oxelytrum selknan, is described from Santa Cruz and Tierra del Fuego provinces, Argentina. The new species resembles Oxelytrum biguttatum (Philippi) in outer aspect, but has different male genitalia, in particular a median lobe longer than the paramera. All the described species of Oxelytrum have the median lobe shorter than the paramera. The internal sac, as far as it could be reconstructed from dry-pinned specimens, also shows differences between the two species. A key to the species of Oxelytrum is given and illustrated. PMID:22773910

[Distribution of aconitum alkaloids in the corpse died of acute aconite intoxication].

PubMed

Liu, Wei; Shen, Min; Qin, Zhi-Qiang

2009-06-01

To investigate the distribution of aconite alkaloids in biological fluids and tissues in the corpse died of acute aconite intoxication and to provide information for sample selection and result evaluation in forensic identification. The content of aconite alkaloids in biological fluids and tissues were determined by liquid chromatography-tandem mass spectrometry. The content of aconite displayed in decending order of urine, bile, gastric content, heart blood, pancreas, heart, intestine, liver, kidney, stomach, lung, gallbladder and spleen, with no aconite detected in the brain. It was indicated that urine, bile and blood are the best specimens for the determination of aconite in body of the acute aconite intoxication.

76 FR 52575 - Health Care for Homeless Veterans Program

Federal Register 2010, 2011, 2012, 2013, 2014

2011-08-23

... environment must be conducive to social interaction, supportive of recovery models and the fullest development... that have multiple uses under one roof, providing shelters, social and health services * * *, and... community as healthy, productive citizens. We also note that VA social workers and caseworkers work closely...

Human autosomal DNA and X chromosome STR profiles obtained from Chrysomya albiceps (Diptera: Calliphoridae) larvae used as a biological trace.

PubMed

Oliveira, T C; Santos, A B R; Rabelo, K C N; Souza, C A; Santos, S M; Crovella, S

2016-11-03

The use of insects to answer questions in criminal investigations, as well as a combination of forensic genetic techniques to obtain human DNA from the organisms, especially necrophagous dipterians, have gained ground in recent decades among researchers and professionals in this area. The objective of our study was to evaluate and compare two methods of human DNA extraction, commonly used for forensic samples, to obtain human autosomal DNA and X chromosome short tandem repeat profiles from the digestive tract of Chrysomya albiceps (Diptera: Calliphoridae) larvae. Immature specimens were collected from corpses at the Institute of Forensic Medicine of Pernambuco and raised in bovine ground meat to allow stabilization of the colony. Groups of larvae in the third instar were provided with bovine ground meat plus human blood for 48 h, dissected, and then subjected to DNA extraction. DNA was extracted using two methods: a DNA IQ™ kit and a phenol-chloroform method. Genomic DNA was amplified using AmpFℓSTR ® Identifiler ® Plus PCR and Argus-X-12 ® kits, and samples were sequenced to determine if the two extraction techniques generated reliable profiles that were compatible with a reference sample. The existence of comparable profiles from both techniques demonstrates the usefulness of dipteran larvae for obtaining human DNA from corpses, which can be further used to correlate genetic profiles in a crime scene when other traces are not available. However, several variables still require revision; thus, the technique should be further investigated for its validity, security, and, in particular, its reproducibility.

Characterization and forensic analysis of soil samples using laser-induced breakdown spectroscopy (LIBS).

PubMed

Jantzi, Sarah C; Almirall, José R

2011-07-01

A method for the quantitative elemental analysis of surface soil samples using laser-induced breakdown spectroscopy (LIBS) was developed and applied to the analysis of bulk soil samples for discrimination between specimens. The use of a 266 nm laser for LIBS analysis is reported for the first time in forensic soil analysis. Optimization of the LIBS method is discussed, and the results compared favorably to a laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) method previously developed. Precision for both methods was <10% for most elements. LIBS limits of detection were <33 ppm and bias <40% for most elements. In a proof of principle study, the LIBS method successfully discriminated samples from two different sites in Dade County, FL. Analysis of variance, Tukey's post hoc test and Student's t test resulted in 100% discrimination with no type I or type II errors. Principal components analysis (PCA) resulted in clear groupings of the two sites. A correct classification rate of 99.4% was obtained with linear discriminant analysis using leave-one-out validation. Similar results were obtained when the same samples were analyzed by LA-ICP-MS, showing that LIBS can provide similar information to LA-ICP-MS. In a forensic sampling/spatial heterogeneity study, the variation between sites, between sub-plots, between samples and within samples was examined on three similar Dade sites. The closer the sampling locations, the closer the grouping on a PCA plot and the higher the misclassification rate. These results underscore the importance of careful sampling for geographic site characterization.

Forensic botany II, DNA barcode for land plants: Which markers after the international agreement?

PubMed

Ferri, G; Corradini, B; Ferrari, F; Santunione, A L; Palazzoli, F; Alu', M

2015-03-01

The ambitious idea of using a short piece of DNA for large-scale species identification (DNA barcoding) is already a powerful tool for scientists and the application of this standard technique seems promising in a range of fields including forensic genetics. While DNA barcoding enjoyed a remarkable success for animal identification through cytochrome c oxidase I (COI) analysis, the attempts to identify a single barcode for plants remained a vain hope for a longtime. From the beginning, the Consortium for the Barcode of Life (CBOL) showed a lack of agreement on a core plant barcode, reflecting the diversity of viewpoints. Different research groups advocated various markers with divergent set of criteria until the recent publication by the CBOL-Plant Working Group. After a four-year effort, in 2009 the International Team concluded to agree on standard markers promoting a multilocus solution (rbcL and matK), with 70-75% of discrimination to the species level. In 2009 our group firstly proposed the broad application of DNA barcoding principles as a tool for identification of trace botanical evidence through the analysis of two chloroplast loci (trnH-psbA and trnL-trnF) in plant species belonging to local flora. Difficulties and drawbacks that were encountered included a poor coverage of species in specific databases and the lack of authenticated reference sequences for the selected markers. Successful preliminary results were obtained providing an approach to progressively identify unknown plant specimens to a given taxonomic rank, usable by any non-specialist botanist or in case of a shortage of taxonomic expertise. Now we considered mandatory to update and to compare our previous findings with the new selected plastid markers (matK+rbcL), taking into account forensic requirements. Features of all the four loci (the two previously analyzed trnH-psbA+trnL-trnF and matK+rbcL) were compared singly and in multilocus solutions to assess the most suitable combination for forensic botany. Based on obtained results, we recommend the adoption of a two-locus combination with rbcL+trnH-psbA plastid markers, which currently best satisfies forensic needs for botanical species identification. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

Revisiting the Genetic Ancestry of Brazilians Using Autosomal AIM-Indels

PubMed Central

Saloum de Neves Manta, Fernanda; Pereira, Rui; Vianna, Romulo; Rodolfo Beuttenmüller de Araújo, Alfredo; Leite Góes Gitaí, Daniel; Aparecida da Silva, Dayse; de Vargas Wolfgramm, Eldamária; da Mota Pontes, Isabel; Ivan Aguiar, José; Ozório Moraes, Milton; Fagundes de Carvalho, Elizeu; Gusmão, Leonor

2013-01-01

There are many different studies that contribute to the global picture of the ethnic heterogeneity in Brazilian populations. These studies use different types of genetic markers and are focused on the comparison of populations at different levels. In some of them, each geographical region is treated as a single homogeneous population, whereas other studies create different subdivisions: political (e.g., pooling populations by State), demographic (e.g., urban and rural), or ethnic (e.g., culture, self-declaration, or skin colour). In this study, we performed an enhanced reassessment of the genetic ancestry of ~ 1,300 Brazilians characterised for 46 autosomal Ancestry Informative Markers (AIMs). In addition, 798 individuals from twelve Brazilian populations representing the five geographical macro-regions of Brazil were newly genotyped, including a Native American community and a rural Amazonian community. Following an increasing North to South gradient, European ancestry was the most prevalent in all urban populations (with values up to 74%). The populations in the North consisted of a significant proportion of Native American ancestry that was about two times higher than the African contribution. Conversely, in the Northeast, Center-West and Southeast, African ancestry was the second most prevalent. At an intrapopulation level, all urban populations were highly admixed, and most of the variation in ancestry proportions was observed between individuals within each population rather than among population. Nevertheless, individuals with a high proportion of Native American ancestry are only found in the samples from Terena and Santa Isabel. Our results allowed us to further refine the genetic landscape of Brazilians while establishing the basis for the effective application of an autosomal AIM panel in forensic casework and clinical association studies within the highly admixed Brazilian populations. PMID:24073242

Technical note: developmental validation of a novel 6-dye typing system with 36 Y-STR loci.

PubMed

Du, Weian; Feng, Peipei; Huang, Hongyan; Wu, Weibin; Zhang, Lei; Guo, Yulin; Liu, Changhui; Liu, Hong; Liu, Chao; Chen, Ling

2018-05-30

Y-chromosomal short tandem repeats (Y-STRs) have proven to be very useful in investigating sexual assault cases and in paternity lineage differentiation. However, currently available commercial Y-STR multiplex amplification systems bear the limitations in the identification of related males from the same paternal lineage due to there being an insufficient number of loci in any single amplification kit. The aim of this study was to establish and validate a novel 6-dye, 36-plex Y-STR multiplex amplification system that incorporated all of the loci present in the Yfiler™ Plus kit (DYS19, DYS385a/b, DYF387S1, DYS389I/II, DYS390, DYS391, DYS392, DYS393, DYS437, DYS438, DYS439, DYS448, DYS449, DYS456, DYS458, DYS460, DYS481, DYS518, DYS533, DYS570, DYS576, DYS627, DYS635, Y_GATA_H4) as well as a further nine highly polymorphic Y-STR loci (DYS388, DYS444, DYS447, DYS522, DYS527a/b, DYS549, DYS596, DYS643). The novel system was optimized and validated by a series of studies that tested the effect of different PCR-based conditions as well as the species specificity, sensitivity, stability, stutter precision, suitability for use on DNA mixtures, reproducibility, and parallel testing of the system, as well as its performance on casework samples and population analysis, according to the SWGDAM developmental validation guidelines. A total of 246 haplotypes were found for the 36 Y-STRs among 247 Guangdong Han unrelated males. Collectively, the results demonstrate that the developed 36-plex Y-STR system is sensitive, robust, reliable, and highly informative for use in forensic genetics.

Male DNA under female fingernails after scratching: transfer and persistence evaluation by RT-PCR analysis and Y-STR typing.

PubMed

Iuvaro, Alessandra; Bini, Carla; Dilloo, Silvia; Sarno, Stefania; Pelotti, Susi

2018-04-17

The collection of biological debris beneath fingernails can be useful in forensic casework when a struggle between the victim and the offender is suspected. In the present study, we set up a controlled scratching experiment in which female volunteers scratched the male volunteers' forearms, simulating a defensive action during an assault. A total of 160 fingernail samples were collected: 80 "control samples" before the scratching, 40 samples immediately after the scratching (t = 0 h), and 40 samples 5 h after the scratching (t = 5 h). The aim was to evaluate, using a real-time PCR approach and Y-STR profiling, the transfer and the persistence of male DNA under female fingernails after scratching. A significant reduction in DNA yield was observed between fingernail samples collected immediately and those collected 5 h after scratching, with a corresponding decrease in Y-STR profile quality. Overall, 38/40 (95%) of the fingernail samples collected immediately (t = 0 h) and 24/40 (60%) of those collected 5 h later (t = 5 h) were suitable for comparison and the scratched male volunteers could not be excluded as donors of the foreign DNA from 37 (92.5%) of the t = 0 h and from 10 (25%) of the t = 5 h profiles. The analysis of male DNA under female fingernails showed that Y-chromosome STR typing may provide extremely valuable genetic information of the male contributor(s), although 5 h after scratching the profile of the scratched male was lost in three-quarters of samples.

Exclusion probabilities and likelihood ratios with applications to mixtures.

PubMed

Slooten, Klaas-Jan; Egeland, Thore

2016-01-01

The statistical evidence obtained from mixed DNA profiles can be summarised in several ways in forensic casework including the likelihood ratio (LR) and the Random Man Not Excluded (RMNE) probability. The literature has seen a discussion of the advantages and disadvantages of likelihood ratios and exclusion probabilities, and part of our aim is to bring some clarification to this debate. In a previous paper, we proved that there is a general mathematical relationship between these statistics: RMNE can be expressed as a certain average of the LR, implying that the expected value of the LR, when applied to an actual contributor to the mixture, is at least equal to the inverse of the RMNE. While the mentioned paper presented applications for kinship problems, the current paper demonstrates the relevance for mixture cases, and for this purpose, we prove some new general properties. We also demonstrate how to use the distribution of the likelihood ratio for donors of a mixture, to obtain estimates for exceedance probabilities of the LR for non-donors, of which the RMNE is a special case corresponding to L R>0. In order to derive these results, we need to view the likelihood ratio as a random variable. In this paper, we describe how such a randomization can be achieved. The RMNE is usually invoked only for mixtures without dropout. In mixtures, artefacts like dropout and drop-in are commonly encountered and we address this situation too, illustrating our results with a basic but widely implemented model, a so-called binary model. The precise definitions, modelling and interpretation of the required concepts of dropout and drop-in are not entirely obvious, and we attempt to clarify them here in a general likelihood framework for a binary model.

Combined use of ESI-QqTOF-MS and ESI-QqTOF-MS/MS with mass-spectral library search for qualitative analysis of drugs.

PubMed

Pavlic, Marion; Libiseller, Kathrin; Oberacher, Herbert

2006-09-01

The potential of the combined use of ESI-QqTOF-MS and ESI-QqTOF-MS/MS with mass-spectral library search for the identification of therapeutic and illicit drugs has been evaluated. Reserpine was used for standardizing experimental conditions and for characterization of the performance of the applied mass spectrometric system. Experiments revealed that because of the mass accuracy, the stability of calibration, and the reproducibility of fragmentation, the QqTOF mass spectrometer is an appropriate platform for establishment of a tandem-mass-spectral library. Three-hundred and nineteen substances were used as reference samples to build the spectral library. For each reference compound, product-ion spectra were acquired at ten different collision-energy values between 5 eV and 50 eV. For identification of unknown compounds, a library search algorithm was developed. The closeness of matching between a measured product-ion spectrum and a spectrum stored in the library was characterized by a value called "match probability", which took into account the number of matched fragment ions, the number of fragment ions observed in the two spectra, and the sum of the intensity differences calculated for matching fragments. A large value for the match probability indicated a close match between the measured and the reference spectrum. A unique feature of the library search algorithm-an implemented spectral purification option-enables characterization of multi-contributor fragment-ion spectra. With the aid of this software feature, substances comprising only 1.0% of the total amount of binary mixtures were unequivocally assigned, in addition to the isobaric main contributors. The spectral library was successfully applied to the characterization of 39 forensic casework samples.

An enhanced computational method for age-at-death estimation based on the pubic symphysis using 3D laser scans and thin plate splines.

PubMed

Stoyanova, Detelina; Algee-Hewitt, Bridget F B; Slice, Dennis E

2015-11-01

The pubic symphysis is frequently used to estimate age-at-death from the adult skeleton. Assessment methods require the visual comparison of the bone morphology against age-informative characteristics that represent a series of phases. Age-at-death is then estimated from the age-range previously associated with the chosen phase. While easily executed, the "morphoscopic" process of feature-scoring and bone-to-phase-matching is known to be subjective. Studies of method and practitioner error demonstrate a need for alternative tools to quantify age-progressive change in the pubic symphysis. This article proposes a more objective, quantitative method that analyzes three-dimensional (3D) surface scans of the pubic symphysis using a thin plate spline algorithm (TPS). This algorithm models the bending of a flat plane to approximately match the surface of the bone and minimizes the bending energy required for this transformation. Known age-at-death and bending energy were used to construct a linear model to predict age from observed bending energy. This approach is tested with scans from 44 documented white male skeletons and 12 casts. The results of the surface analysis show a significant association (regression p-value = 0.0002 and coefficient of determination = 0.2270) between the minimum bending energy and age-at-death, with a root mean square error of ≈19 years. This TPS method yields estimates comparable to established methods but offers a fully integrated, objective and quantitative framework of analysis and has potential for use in archaeological and forensic casework. © 2015 Wiley Periodicals, Inc.

Northern Slavs from Serbia do not show a founder effect at autosomal and Y-chromosomal STRs and retain their paternal genetic heritage.

PubMed

Rębała, Krzysztof; Veselinović, Igor; Siváková, Daniela; Patskun, Erika; Kravchenko, Sergey; Szczerkowska, Zofia

2014-01-01

Studies on Y-chromosomal markers revealed significant genetic differentiation between Southern and Northern (Western and Eastern) Slavic populations. The northern Serbian region of Vojvodina is inhabited by Southern Slavic Serbian majority and, inter alia, Western Slavic (Slovak) and Eastern Slavic (Ruthenian) minorities. In the study, 15 autosomal STR markers were analysed in unrelated Slovaks, Ruthenians and Serbs from northern Serbia and western Slovakia. Additionally, Slovak males from Serbia were genotyped for 17 Y-chromosomal STR loci. The results were compared to data available for other Slavic populations. Genetic distances for autosomal markers revealed homogeneity between Serbs from northern Serbia and Slovaks from western Slovakia and distinctiveness of Serbian Slovaks and Ruthenians. Y-STR variation showed a clear genetic departure of the Slovaks and Ruthenians inhabiting Vojvodina from their Serbian neighbours and genetic similarity to the Northern Slavic populations of Slovakia and Ukraine. Admixture estimates revealed negligible Serbian paternal ancestry in both Northern Slavic minorities of Vojvodina, providing evidence for their genetic isolation from the Serbian majority population. No reduction of genetic diversity at autosomal and Y-chromosomal markers was found, excluding genetic drift as a reason for differences observed at autosomal STRs. Analysis of molecular variance detected significant population stratification of autosomal and Y-chromosomal microsatellites in the three Slavic populations of northern Serbia, indicating necessity for separate databases used for estimations of frequencies of autosomal and Y-chromosomal STR profiles in forensic casework. Our results demonstrate that regarding Y-STR haplotypes, Serbian Slovaks and Ruthenians fit in the Eastern European metapopulation defined in the Y chromosome haplotype reference database. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

Age estimation of bloodstains using smartphones and digital image analysis.

PubMed

Thanakiatkrai, Phuvadol; Yaodam, Alisa; Kitpipit, Thitika

2013-12-10

Recent studies on bloodstains have focused on determining the time since deposition of bloodstains, which can provide useful temporal information to forensic investigations. This study is the first to use smartphone cameras in combination with a truly low-cost illumination system as a tool to estimate the age of bloodstains. Bloodstains were deposited on various substrates and photographed with a smartphone camera. Three smartphones (Samsung Galaxy S Plus, Apple iPhone 4, and Apple iPad 2) were compared. The environmental effects - temperature, humidity, light exposure, and anticoagulant - on the bloodstain age estimation process were explored. The color values from the digital images were extracted and correlated with time since deposition. Magenta had the highest correlation (R(2)=0.966) and was used in subsequent experiments. The Samsung Galaxy S Plus was the most suitable smartphone as its magenta decreased exponentially with increasing time and had highest repeatability (low variation within and between pictures). The quantifiable color change observed is consistent with well-established hemoglobin denaturation process. Using a statistical classification technique called Random Forests™, we could predict bloodstain age accurately up to 42 days with an error rate of 12%. Additionally, the age of forty blind stains were all correctly predicted, and 83% of mock casework samples were correctly classified. No within- and between-person variations were observed (p>0.05), while smartphone camera, temperature, humidity, and substrate color influenced the age determination process in different ways. Our technique provides a cheap, rapid, easy-to-use, and truly portable alternative to more complicated analysis using specialized equipment, e.g. spectroscopy and HPLC. No training is necessary with our method, and we envision a smartphone application that could take user inputs of environmental factors and provide an accurate estimate of bloodstain age. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

Persistence of DNA on clothes after exposure to water for different time periods-a study on bathtub, pond, and river.

PubMed

Helmus, Janine; Zorell, Sarah; Bajanowski, Thomas; Poetsch, Micaela

2018-01-01

DNA traces on clothes of drowned bodies can provide important evidence for police investigations, especially in cases of suspected suicides or homicides. However, it is generally assumed that the water "erodes" a large part of the DNA depending especially on the exposure time. In forensic casework, DNA of suspects could be found frequently on clothes of drowned bodies after hours, sometimes days of exposure to water. This study was conducted to attempt a general statement about the conditions under which sufficient DNA remains can be expected for molecular genetic analysis. For this purpose, different scenarios were designed including DNA from three to five people, different types of waters (tap, pond, bathtub and river) for various time periods, with higher water pressure, different temperature, and soapy water (bathtub). Epithelial cells and blood cells were mounted on cotton cloths, and the DNA left after exposure was analyzed using the Powerplex® ESX17fast kit. In the indoor experiments, complete profiles could be seen even after 10 min rinsing of clothes under the tap and after 1 week in the bathtub. Outdoors, the results differed considerably between summer and winter as well as between pond and river. The longest exposure time still resulting in a complete profile was 2 weeks for a sample with skin cells in the pond during winter. In summer, the time period for erasing the bulk of DNA was 4 hours regarding epithelial samples and more than 1 day for blood samples in pond and river environments. All in all, the results demonstrate that DNA could still be recovered from clothes exposed to water for more than 1 week.

Investigation of Latent Traces Using Infrared Reflectance Hyperspectral Imaging

NASA Astrophysics Data System (ADS)

Schubert, Till; Wenzel, Susanne; Roscher, Ribana; Stachniss, Cyrill

2016-06-01

The detection of traces is a main task of forensics. Hyperspectral imaging is a potential method from which we expect to capture more fluorescence effects than with common forensic light sources. This paper shows that the use of hyperspectral imaging is suited for the analysis of latent traces and extends the classical concept to the conservation of the crime scene for retrospective laboratory analysis. We examine specimen of blood, semen and saliva traces in several dilution steps, prepared on cardboard substrate. As our key result we successfully make latent traces visible up to dilution factor of 1:8000. We can attribute most of the detectability to interference of electromagnetic light with the water content of the traces in the shortwave infrared region of the spectrum. In a classification task we use several dimensionality reduction methods (PCA and LDA) in combination with a Maximum Likelihood classifier, assuming normally distributed data. Further, we use Random Forest as a competitive approach. The classifiers retrieve the exact positions of labelled trace preparation up to highest dilution and determine posterior probabilities. By modelling the classification task with a Markov Random Field we are able to integrate prior information about the spatial relation of neighboured pixel labels.

Maryland Family Support Services Consortium. Final Report.

ERIC Educational Resources Information Center

Gardner, James F.; Markowitz, Ricka Keeney

The Maryland Family Support Services Consortium is a 3-year demonstration project which developed unique family support models at five sites serving the needs of families with a developmentally disabled child (ages birth to 21). Caseworkers provided direct intensive services to 224 families over the 3-year period, including counseling, liaison and…

Ethical Accountability and Routine Moral Stress in Special Educational Needs Professionals

ERIC Educational Resources Information Center

Hellawell, Beate

2015-01-01

This small-scale interview study considers experiences, difficulties and dilemmas of local Special Educational Needs (SEN) professionals such as SEN caseworkers, and examines the neglected ethical dimensions of their role. It argues that fostering "ethical knowledge" (Campbell, 2003), rather than an increase in prescriptive guidance,…

Patterns of Maternal Behavior among Neglectful Families: Implications for Research and Intervention

ERIC Educational Resources Information Center

Wilson, Samantha L.; Kuebli, Janet E.; Hughes, Honore M.

2005-01-01

Objective: The heterogeneity within neglecting caregivers has not been explored in an empirical fashion. The current study sought to address this limitation by utilizing archival data in order to explore variability of maternal behavior among neglectful families. Method: The current study utilized archival data containing caseworker and…

Changing Problem Behavior Using Solution Parenting.

ERIC Educational Resources Information Center

Schatz, Mona Struhsaker; Zimmerman, Toni Schindler; Watson, Catherine

Solution parenting is designed to provide both foster parents and caseworkers a new kind of parenting for difficult children and youth in placement. The specialized training program is for those who will teach solution parenting. Objectives for trainees include: (1) identify small, positive behavioral changes; (2) recognize and use pre-existing…

The Use of Genograms in Educational Psychology Practice

ERIC Educational Resources Information Center

Tobias, Adele

2018-01-01

This article explores the application of the genogram in educational psychology (EP) practice. It provides a brief overview of the historical and theoretical development of the genogram. It then reviews and critiques some of the current literature regarding clinical application of the genogram in casework with children and adolescents and their…

Frontline Worker Responses to Domestic Violence Disclosure in Public Welfare Offices

ERIC Educational Resources Information Center

Lindhorst, Taryn; Casey, Erin; Meyers, Marcia

2010-01-01

Although substantial numbers of women seeking Temporary Assistance for Needy Families (TANF) report domestic violence, few receive mandated services through the Family Violence Option (FVO). This study used transcripts of interviews between welfare caseworkers and their clients to identify and classify the responses made by workers to client…

What Does the Social Worker Do Anyway?

ERIC Educational Resources Information Center

Koocher, Robin C.

Social workers at the Boston Center for Blind Children function in the following areas: supportive casework with the parents of handicapped, visually-impaired children; coordination of services and resources to the children and families involved; and dissemination of information to the staffs of other agencies regarding Boston Center. The most…

STUDIES OF TROUBLESOME CHILDREN.

ERIC Educational Resources Information Center

STOTT, D.H.

TWO STUDIES ARE REPORTED AND THEIR IMPLICATIONS DISCUSSED. IN THE FIRST STUDY AN ATTEMPT WAS MADE TO AVERT DELINQUENCY IN CHILDREN (AGED 12 AND 13) BY IDENTIFYING THE DELINQUENCY PRONE AND TREATING A PORTION OF THEM BY FAMILY CASEWORK METHODS. THROUGH USE OF THE DELINQUENCY PREDICTION INSTRUMENT AND THE BRISTOL SOCIAL ADJUSTMENT GUIDES, 33…

A Clinical Consultation Model for Child Welfare Supervisors

ERIC Educational Resources Information Center

Strand, Virginia C.; Badger, Lee

2007-01-01

This article presents findings from a consultation project conducted by faculty from six schools of social work with approximately 150 child welfare supervisors over a two-year period. The purpose of the program was to assist supervisors with their roles as educators, mentors, and coaches for casework staff, specifically in relationship to case…

Family Assessment in Child Welfare: The Illinois DCFS Integrated Assessment Program in Policy and Practice

ERIC Educational Resources Information Center

Smithgall, Cheryl; Jarpe-Ratner, Elizabeth; Yang, Duck-Hye; DeCoursey, Jan; Brooks, LaShaun; Goerge, Robert

2009-01-01

Launched in 2005, the Illinois Integrated Assessment (IA) program partners child welfare caseworkers with licensed clinicians to provide better information about the functioning of children entering foster care and about child and family strengths, support systems, and service needs. The information-gathering activities and the collaborative…

A DEMONSTRATION PROJECT IN THE DEVELOPMENT OF RURAL CHILD CARE.

ERIC Educational Resources Information Center

1964

THIS DEMONSTRATION PROJECT WAS DESIGNED FOR SEVEN EASTERN KENTUCKY COUNTIES WHICH ARE AMONG THE MOST IMPOVERISHED IN THE UNITED STATES. IN ORDER TO ALLEVIATE THE PROBLEM, THREE PROGRAMS WERE TO BE IMPLEMENTED, INCLUDING--(1) DAY CARE FOR PRESCHOOL CHILDREN, (2) HOMEMAKER SERVICE FOR FAMILIES, AND (3) CASEWORK SERVICE WITH BOTH PARENTS AND…

Predicting and Managing Turnover in Human Service Agencies: A Case Study of an Organization in Crisis.

ERIC Educational Resources Information Center

Balfour, Danny L.; Neff, Donna M.

1993-01-01

A logistic regression model applied to data from 171 child service caseworkers identified variables determining job turnover during times of intense external criticism of the agency (length of service, professional commitment, level of education). A special training program did not significantly reduce the probability of turnover. (SK)

Organizational Climate, Services, and Outcomes in Child Welfare Systems

ERIC Educational Resources Information Center

Glisson, Charles; Green, Philip

2011-01-01

Objective: This study examines the association of organizational climate, casework services, and youth outcomes in child welfare systems. Building on preliminary findings linking organizational climate to youth outcomes over a 3-year follow-up period, the current study extends the follow-up period to 7 years and tests main, moderating and…

The Whole Child Matters: The Challenge of "Every Child Matters" for Pastoral Care

ERIC Educational Resources Information Center

Best, Ron

2007-01-01

Pastoral care embodies the idea that schools should not limit their activities to the transmission of knowledge but should educate the whole child. This paper outlines five "pastoral tasks", casework, preventive work, pastoral curriculum, community building and management, and considers how each might contribute to the five desired…

3 CFR 8481 - Proclamation 8481 of March 2, 2010. Women's History Month, 2010

Code of Federal Regulations, 2011 CFR

2011-01-01

.... Women from all walks of life have improved their communities and our Nation. Sylvia Mendez and her... a caseworker in city government, Dr. Dorothy Height has dedicated her life to building a more just... higher pay on average for the same work. Women also hold disproportionately fewer science and engineering...

Posttraumatic Stress Symptoms and Trajectories in Child Sexual Abuse Victims: An Analysis of Sex Differences Using the National Survey of Child and Adolescent Well-Being

PubMed Central

Koenen, Karestan C.; Jaffee, Sara R.

2011-01-01

Very few studies have prospectively examined sex differences in posttraumatic stress symptoms and symptom trajectories in youth victimized by childhood sexual abuse. This study addresses that question in a relatively large sample of children, drawn from the National Survey of Child and Adolescent Well-Being, who were between the ages of 8–16 years and who were reported to Child Protective Services for alleged sexual abuse. Sex differences were examined using t tests, logistic regression, and latent trajectory modeling. Results revealed that there were not sex differences in victims’ posttraumatic stress symptoms or trajectories. Whereas caseworkers substantiated girls’ abuse at higher rates than boys’ abuse and rated girls significantly higher than boys on level of harm, there were not sex differences in three more objective measures of abuse severity characteristics. Overall, higher caseworker ratings of harm predicted higher initial posttraumatic stress symptom levels, and substantiation status predicted shallower decreases in trauma symptoms over time. Implications for theory and intervention are discussed. PMID:19221872

Psychoanalytic application and psychoanalytic integrity.

PubMed

O'Neill, Sylvia

2005-02-01

In this article, the author offers an analysis of psychoanalytic application, defined as the breaking of new conceptual ground in some field of knowledge whereby the new idea is conceived, and later articulated, with the aid of reference to analogous phenomena in psychoanalysis. It requires apt analogy based on competent understanding of the applied field and of psychoanalysis. Only when the relevant differences between the applied and psychoanalytic fields are grasped can the extent of certain parallels emerge. The thinking by analogy that comprises psychoanalytic application may be intuitive and implicit, but should be susceptible of explicit theoretical elaboration that specifies, precisely, the point(s) of correspondence between psychoanalysis and the applied field in relation to a precise specification of their relevant differences. Applied psychotherapy at the interface of the internal and external worlds (historically rooted in casework) is employed as a model. By analogy with Donnet's concept of the analytic site, the author proposes the concept of the psychodynamic (case)work site, and elaborates it for that applied field in order to elucidate the proposed principles of psychoanalytic application.

Defense Forensics: Additional Planning and Oversight Needed to Establish an Enduring Expeditionary Forensic Capability

DTIC Science & Technology

2013-06-01

forensic pathology, forensic anthropology, and forensic toxicology . 13DOD’s forensic directive defines DOD components as the Office of the...DEFENSE FORENSICS Additional Planning and Oversight Needed to Establish an Enduring Expeditionary Forensic ...COVERED 00-00-2013 to 00-00-2013 4. TITLE AND SUBTITLE Defense Forensics : Additional Planning and Oversight Needed to Establish an Enduring

Bringing colour back after 70 years: Predicting eye and hair colour from skeletal remains of World War II victims using the HIrisPlex system.

PubMed

Chaitanya, Lakshmi; Pajnič, Irena Zupanič; Walsh, Susan; Balažic, Jože; Zupanc, Tomaž; Kayser, Manfred

2017-01-01

Retrieving information about externally visible characteristics from DNA can provide investigative leads to find unknown perpetrators, and can also help in disaster victim and other missing person identification cases. Aiming for the application to both types of forensic casework, we previously developed and forensically validated the HIrisPlex test system enabling parallel DNA prediction of eye and hair colour. Although a recent proof-of-principle study demonstrated the general suitability of the HIrisPlex system for successfully analysing DNA from bones and teeth of various storage times and conditions, practical case applications to human remains are scarce. In this study, we applied the HIrisPlex system to 49 DNA samples obtained from bones or teeth of World War II victims excavated at six sites, mostly mass graves, in Slovenia. PCR-based DNA quantification ranged from 4pg/μl to 313pg/μl and on an average was 41pg/μl across all samples. All 49 samples generated complete HIrisPlex profiles with the exception of one MC1R DNA marker (N29insA) missing in 83.7% of the samples. In 44 of the 49 samples (89.8%) complete 15-loci autosomal STR (plus amelogenin) profiles were obtained. Of 5 pairs of skeletal remains for which STR profiling suggested an origin in the same individuals, respectively, 4 showed the same HIrisPlex profiles and predicted eye and hair colours, respectively, while discrepancies in one pair (sample 26 and 43) are likely to be explained by DNA quantity and quality issues observed in sample 43. Sample 43 had the lowest DNA concentration of only 4pg/μl, producing least reliable STR results and could be misleading in concluding that samples 43 and 26 originate from the same individual. The HIrisPlex-predicted eye and hair colours from two skeletal samples, suggested to derive from two brothers via STR profiling together with a living sister, were confirmed by the living sister's report. Overall, we demonstrate that after more than 70 years, HIrisPlex-based eye and hair colour prediction from skeletal remains is feasible with high success rate. Our results further encourage the use of the HIrisPlex system in missing person/disaster victim identification to aid the identification process in cases where ante-mortem samples or putative relatives are not directly available, and DNA predicted eye and hair colour information provides leads for locating them, allowing STRbased individual identification. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Ultrastructure analysis of the immature stages of Ravinia belforti (Diptera: Sarcophagidae), a species of medical-veterinary and forensic importance, by scanning electron microscopy.

PubMed

da-Silva-Xavier, Alexandre; de Carvalho Queiroz, Margareth Maria

2016-07-01

The postmortem interval is related to the age of immature species of flies found on corpses and can be estimated using data available in the literature on the biology of the species. The flesh fly Ravinia belforti is a carrier of enteric pathogens that can affect human and animal health as well as being of forensic importance. As the morphology of many immature Sarcophagidae is unknown, these immature forms must be collected and characterized after the emergence of the adult male. Here we describe and analyze the morphological characteristics of the larvae stages L1, L2, L3 and the puparium of R. belforti by scanning electron microscopy (SEM). Ten specimens of each stage were analyzed. Larvae of R. belforti follow the typical muscoid vermiform pattern with 12 segments. The anterior region is pointed, while the posterior region is thicker. The spines of the cephalic collar are flattened and with double, triple or quadruple points, different from the spines along the body that only have a single point. In L2, the anterior spiracle is present with a varying number of papillae (16-22), differing from other species. The posterior spiracles are located within the peritreme. The spiracular cavity is internalized in the posterior region, following the pattern that differs Sarcophagidae from other families. L3 features more visible and developed spines around the cephalic collar, getting thicker and denser near to the first thoracic segment. Puparium is similar to other species of Sarcophagidae. This paper presents important data on this family which has both health and forensic importance. Furthermore, R. belforti shows significant differences from other species of Sarcophagidae. Copyright © 2016 Elsevier B.V. All rights reserved.

The presence of enterovirus, adenovirus, and parvovirus B19 in myocardial tissue samples from autopsies: an evaluation of their frequencies in deceased individuals with myocarditis and in non-inflamed control hearts.

PubMed

Nielsen, Trine Skov; Hansen, Jakob; Nielsen, Lars Peter; Baandrup, Ulrik Thorngren; Banner, Jytte

2014-09-01

Multiple viruses have been detected in cardiac tissue, but their role in causing myocarditis remains controversial. Viral diagnostics are increasingly used in forensic medicine, but the interpretation of the results can sometimes be challenging. In this study, we examined the prevalence of adenovirus, enterovirus, and parvovirus B19 (PVB) in myocardial autopsy samples from myocarditis related deaths and in non-inflamed control hearts in an effort to clarify their significance as the causes of myocarditis in a forensic material. We collected all autopsy cases diagnosed with myocarditis from 1992 to 2010. Eighty-four suicidal deaths with morphologically normal hearts served as controls. Polymerase chain reaction was used for the detection of the viral genomes (adenovirus, enterovirus, and PVB) in myocardial tissue specimens. The distinction between acute and persistent PVB infection was made by the serological determination of PVB-specific immunoglobulins M and G. PVB was detected in 33 of 112 (29 %) myocarditis cases and 37 of 84 (44 %) control cases. All of the samples were negative for the presence of adenovirus and enterovirus. Serological evidence of an acute PVB infection, determined by the presence of immunoglobulin M, was only present in one case. In the remaining cases, PVB was considered to be a bystander with no or limited association to myocardial inflammation. In this study, adenovirus, enterovirus, and PVB were found to be rare causes of myocarditis. The detection of PVB in myocardial autopsy samples most likely represents a persistent infection with no or limited association with myocardial inflammation. The forensic investigation of myocardial inflammation demands a thorough examination, including special attention to non-viral causes and requires a multidisciplinary approach.

Identification of Forensically Important Calliphoridae and Sarcophagidae Species Collected in Korea Using SNaPshot Multiplex System Targeting the Cytochrome c Oxidase Subunit I Gene

PubMed Central

Park, Ji Hye

2018-01-01

Estimation of postmortem interval (PMI) is paramount in modern forensic investigation. After the disappearance of the early postmortem phenomena conventionally used to estimate PMI, entomologic evidence provides important indicators for PMI estimation. The age of the oldest fly larvae or pupae can be estimated to pinpoint the time of oviposition, which is considered the minimum PMI (PMImin). The development rate of insects is usually temperature dependent and species specific. Therefore, species identification is mandatory for PMImin estimation using entomological evidence. The classical morphological identification method cannot be applied when specimens are damaged or have not yet matured. To overcome this limitation, some investigators employ molecular identification using mitochondrial cytochrome c oxidase subunit I (COI) nucleotide sequences. The molecular identification method commonly uses Sanger's nucleotide sequencing and molecular phylogeny, which are complex and time consuming and constitute another obstacle for forensic investigators. In this study, instead of using conventional Sanger's nucleotide sequencing, single-nucleotide polymorphisms (SNPs) in the COI gene region, which are unique between fly species, were selected and targeted for single-base extension (SBE) technology. These SNPs were genotyped using a SNaPshot® kit. Eleven Calliphoridae and seven Sarcophagidae species were covered. To validate this genotyping, fly DNA samples (103 adults, 84 larvae, and 4 pupae) previously confirmed by DNA barcoding were used. This method worked quickly with minimal DNA, providing a potential alternative to conventional DNA barcoding. Consisting of only a few simple electropherogram peaks, the results were more straightforward compared with those of the conventional DNA barcoding produced by Sanger's nucleotide sequencing. PMID:29682531