The Experts below are selected from a list of 14526 Experts worldwide ranked by ideXlab platform
Chris Lennard - One of the best experts on this subject based on the ideXlab platform.
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Forensic Application of laser-induced breakdown spectroscopy for the discrimination of questioned documents
Forensic science international, 2015Co-Authors: Chris Lennard, Moteaa M. El-deftar, James RobertsonAbstract:Document examination is an important Forensic discipline and the legal system regularly needs the knowledge and skills of the scientific expert when questioned documents are involved in criminal or civil matters. Amongst the many aspects of the scientific examination of documents, elemental analysis can provide useful results. In this study, the evaluation of the analytical performance of a commercially available laser-induced breakdown spectroscopy (LIBS) instrument was conducted on office papers, writing inks, inkjet inks and laser printer toners. The paper sample set analysed consisted of 33 Australian paper specimens originating from the same production plant but representing different brands and/or batches. In addition, a total of 131 ink or toner samples were examined that included black and blue ballpoint inks, black inkjet inks, and black laser printer toners originating from several manufacturing sources, models and/or batches. Results from the LIBS method were compared against those obtained using more established elemental profiling method such as laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS). LIBS demonstrated detectable and significant differences between different batches of the same brand as well as between different brands of paper, ink and toner samples. The LIBS method provided comparable discrimination powers for the selected sample sets when compared to those obtained using LA-ICP-MS (discrimination from 99.8 and 100% of the sample pairs, depending on the sample subset under examination). LIBS is a suitable technique for the determination of elemental composition as part of a protocol for the examination of questioned documents.
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Stable isotope Forensics: an introduction to the Forensic Application of stable isotope analysis
Australian Journal of Forensic Sciences, 2012Co-Authors: Chris LennardAbstract:Stable isotope Forensics: an introduction to the Forensic Application of stable isotope analysis, by W. Meier-Augenstein, Chichester, UK, Wiley-Blackwell, 2010, 296 pp, $110 (hardback), ISBN 047051...
Suhua Zhang - One of the best experts on this subject based on the ideXlab platform.
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developmental validation of a custom panel including 273 snps for Forensic Application using ion torrent pgm
Forensic Science International-genetics, 2017Co-Authors: Suhua Zhang, Ying-nan Bian, Anqi Chen, Hancheng Zheng, Yuzhen Gao, Yiping HouAbstract: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.
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development of a new 26plex y strs typing system for Forensic Application
Forensic Science International-genetics, 2014Co-Authors: Suhua Zhang, Zheng Wang, Huaizhou Tian, Shumin ZhaoAbstract:In this study, 26plex Y-STRs typing system, including 17 Y-STRs (DYS19, DYS389I, DYS389II, DYS390, DYS391, DYS392, DYS393, DYS385ab, DYS437, DYS438, DYS439, DYS448, DYS456, DYS458, DYS635 and GATA H4) recommended as YHRD standard loci and nine new highly discriminating Y-STRs (DYS549, DYS643, DYS388, DYS570, DYS533, DYS576, DYS460, DYS481 and DYS449), was established with 5-dye fluorescences labelling. Developmental validation indicated that the 26plex Y-STRs typing system was reproducible, accurate, sensitive and robust. The sensitivity of the system was such that a full profile was obtainable even with 125pg of male DNA. Specificity testing was demonstrated by the lack of cross-reactivity with a variety of commonly encountered animal species and bacteria. Also, the multiplex is suitable for mixture study. An average of above 97% of the minor alleles detected with the male/male mixture with 1:3 and 3:1 ratios, while an average of above 70% of the minor alleles detected with the male/male mixture with 1:19 and 19:1 ratios. Full profiles are consistently detected with 125pg of male DNA, even in the presence of excessive amounts of female DNA. In addition, the whole PCR amplification of the 26 Y-STRs can finish in 1h, making the multiplex system suitable for fast-detection. For the Forensic evaluation of the multiplex system, 516 haplotypes were found among 517 unrelated males. HD of the multiplex system was 0.9999925 while DC was 0.9980658, which is suitable for Forensic Application.
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Forensic Application of 30 InDel loci in Han and She nationalities of Eastern China
Fa yi xue za zhi, 2014Co-Authors: Zheng Wang, Suhua Zhang, Ruxin Zhu, Shumin Zhao, Kuan SunAbstract:OBJECTIVE To evaluate the Forensic Application value of 30 insertion/deletion (InDel) loci included in Investigator DIPplex Kit in Han and She nationalities of Eastern China. METHODS A total of 565 unrelated individuals in Han nationality and 119 ones in She nationality of Eastern China were investigated using Investigator DIPplex Kit. Allele frequencies, population genetics parameters of the 30 InDel loci were statistically calculated. RESULTS In Han nationality, the mean Ho was 0.413 3, the mean DP was 0.551 1, the mean PIC was 0.320 0. And in She nationality, the mean Ho was 0.389 6, the mean DP was 0.543 3, the mean PIC was 0.310 0. No deviation from Hardy-Weinberg equilibrium was observed in Han and She nationalities (P > 0.05). CONCLUSION The 30 loci in Investigator DIPplex Kit show good genetic diversity in Han and She nationalities, and could be used as a supplemental tool for some special paternity cases.
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a new multiplex assay of 17 autosomal strs and amelogenin for Forensic Application
PLOS ONE, 2013Co-Authors: Suhua Zhang, Huaizhou Tian, Shumin ZhaoAbstract:This paper describes a newly devised autosomal short tandem repeat (STR) multiplex polymerase chain reaction (PCR) systems for 17 autosomal loci (D1S1656, D2S441, D3S1358, D3S3045, D6S477, D7S3048, D8S1132, D10S1435, D10S1248, D11S2368, D13S325, D14S608, D15S659, D17S1290, D18S535, D19S253 and D22-GATA198B05) and Amelogenin. Primers for the loci were designed and optimized so that all of the amplicons were distributed from 50 base pairs (bp) to less than 500 bp within a five-dye chemistry design with the fifth dye reserved for the sizing standard. Strategies were developed to overcome challenges that encountered in creating the final assay. The limits of the multiplex were tested, resulting in the successful amplification of genomic DNA range from 0.25–4 ng with 30 PCR cycles. A total of 681 individuals from the Chinese Han population were studied and Forensic genetic data were present. No significant deviations from Hardy–Weinberg equilibrium were observed. A total of 180 alleles were detected for the 17 autosomal STRs. The cumulative mean exclusion chance in duos (CMECD) was 0.999967, and cumulative mean exclusion chance in trios (CMECT) was 0.99999995. We conclude that the present 17plex autosomal STRs assay provides an additional powerful tool for Forensic Applications.
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Forensic Application of investigator HDplex kit in Han nationality of Eastern China
Fa yi xue za zhi, 2012Co-Authors: Suhua Zhang, Zheren Zhang, Kuan Sun, Zhenmin ZhaoAbstract:OBJECTIVE To investigate the genetic data of 12 autosomal STR loci included in Investigator HDplex kit and to evaluate its Forensic Application in Han nationality of Eastern China. METHODS A total of 484 unrelated healthy individuals in Han nationality of Eastern China were investigated with Investigator HDplex kit. Allele frequencies, population genetics parameters and linkage disequilibrium information of the 12 autosomal STR loci were statistically analyzed. RESULTS No deviations from Hardy-Weinberg equilibrium were detected and all loci were independent form each other within the studied 484 unrelated healthy individuals. DP values of the 12 autosomal STR loci were all above 0.8, and CDP was 0.999 999 999 92. The cumulative probability of paternity exclusion in duo and in trio were 0.999 82 and 0.999 998 6, respectively. CONCLUSION Investigator HDplex kit with 12 highly polymorphic STR loci in Han nationality of Eastern China could be used effectively for Forensic DNA genotyping.
Janet M Hurley - One of the best experts on this subject based on the ideXlab platform.
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applying the principles of isotope analysis in plant and animal ecology to Forensic science in the americas
Oecologia, 2018Co-Authors: Lesley A Chesson, Janet E Barnette, Gabriel J Bowen, Renee J Brooks, John F Casale, Thure E Cerling, Craig S Cook, C B Douthitt, John D Howa, Janet M HurleyAbstract:The heart of Forensic science is Application of the scientific method and analytical approaches to answer questions central to solving a crime: Who, What, When, Where, and How. Forensic practitioners use fundamentals of chemistry and physics to examine evidence and infer its origin. In this regard, ecological researchers have had a significant impact on Forensic science through the development and Application of a specialized measurement technique—isotope analysis—for examining evidence. Here, we review the utility of isotope analysis in Forensic settings from an ecological perspective, concentrating on work from the Americas completed within the last three decades. Our primary focus is on combining plant and animal physiological models with isotope analyses for source inference. Examples of the Forensic Application of isotopes—including stable isotopes, radiogenic isotopes, and radioisotopes—span from cotton used in counterfeit bills to anthrax shipped through the U.S. Postal Service and from beer adulterated with cheap adjuncts to human remains discovered in shallow graves. Recent methodological developments and the generation of isotope landscapes, or isoscapes, for data interpretation promise that isotope analysis will be a useful tool in ecological and Forensic studies for decades to come.
Shumin Zhao - One of the best experts on this subject based on the ideXlab platform.
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development of a new 26plex y strs typing system for Forensic Application
Forensic Science International-genetics, 2014Co-Authors: Suhua Zhang, Zheng Wang, Huaizhou Tian, Shumin ZhaoAbstract:In this study, 26plex Y-STRs typing system, including 17 Y-STRs (DYS19, DYS389I, DYS389II, DYS390, DYS391, DYS392, DYS393, DYS385ab, DYS437, DYS438, DYS439, DYS448, DYS456, DYS458, DYS635 and GATA H4) recommended as YHRD standard loci and nine new highly discriminating Y-STRs (DYS549, DYS643, DYS388, DYS570, DYS533, DYS576, DYS460, DYS481 and DYS449), was established with 5-dye fluorescences labelling. Developmental validation indicated that the 26plex Y-STRs typing system was reproducible, accurate, sensitive and robust. The sensitivity of the system was such that a full profile was obtainable even with 125pg of male DNA. Specificity testing was demonstrated by the lack of cross-reactivity with a variety of commonly encountered animal species and bacteria. Also, the multiplex is suitable for mixture study. An average of above 97% of the minor alleles detected with the male/male mixture with 1:3 and 3:1 ratios, while an average of above 70% of the minor alleles detected with the male/male mixture with 1:19 and 19:1 ratios. Full profiles are consistently detected with 125pg of male DNA, even in the presence of excessive amounts of female DNA. In addition, the whole PCR amplification of the 26 Y-STRs can finish in 1h, making the multiplex system suitable for fast-detection. For the Forensic evaluation of the multiplex system, 516 haplotypes were found among 517 unrelated males. HD of the multiplex system was 0.9999925 while DC was 0.9980658, which is suitable for Forensic Application.
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Forensic Application of 30 InDel loci in Han and She nationalities of Eastern China
Fa yi xue za zhi, 2014Co-Authors: Zheng Wang, Suhua Zhang, Ruxin Zhu, Shumin Zhao, Kuan SunAbstract:OBJECTIVE To evaluate the Forensic Application value of 30 insertion/deletion (InDel) loci included in Investigator DIPplex Kit in Han and She nationalities of Eastern China. METHODS A total of 565 unrelated individuals in Han nationality and 119 ones in She nationality of Eastern China were investigated using Investigator DIPplex Kit. Allele frequencies, population genetics parameters of the 30 InDel loci were statistically calculated. RESULTS In Han nationality, the mean Ho was 0.413 3, the mean DP was 0.551 1, the mean PIC was 0.320 0. And in She nationality, the mean Ho was 0.389 6, the mean DP was 0.543 3, the mean PIC was 0.310 0. No deviation from Hardy-Weinberg equilibrium was observed in Han and She nationalities (P > 0.05). CONCLUSION The 30 loci in Investigator DIPplex Kit show good genetic diversity in Han and She nationalities, and could be used as a supplemental tool for some special paternity cases.
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a new multiplex assay of 17 autosomal strs and amelogenin for Forensic Application
PLOS ONE, 2013Co-Authors: Suhua Zhang, Huaizhou Tian, Shumin ZhaoAbstract:This paper describes a newly devised autosomal short tandem repeat (STR) multiplex polymerase chain reaction (PCR) systems for 17 autosomal loci (D1S1656, D2S441, D3S1358, D3S3045, D6S477, D7S3048, D8S1132, D10S1435, D10S1248, D11S2368, D13S325, D14S608, D15S659, D17S1290, D18S535, D19S253 and D22-GATA198B05) and Amelogenin. Primers for the loci were designed and optimized so that all of the amplicons were distributed from 50 base pairs (bp) to less than 500 bp within a five-dye chemistry design with the fifth dye reserved for the sizing standard. Strategies were developed to overcome challenges that encountered in creating the final assay. The limits of the multiplex were tested, resulting in the successful amplification of genomic DNA range from 0.25–4 ng with 30 PCR cycles. A total of 681 individuals from the Chinese Han population were studied and Forensic genetic data were present. No significant deviations from Hardy–Weinberg equilibrium were observed. A total of 180 alleles were detected for the 17 autosomal STRs. The cumulative mean exclusion chance in duos (CMECD) was 0.999967, and cumulative mean exclusion chance in trios (CMECT) was 0.99999995. We conclude that the present 17plex autosomal STRs assay provides an additional powerful tool for Forensic Applications.
John R. Lombardi - One of the best experts on this subject based on the ideXlab platform.
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Application of raman spectroscopy and surface enhanced raman scattering to the analysis of synthetic dyes found in ballpoint pen inks
Journal of Forensic Sciences, 2009Co-Authors: B S Irina Geiman, Marco Leona, John R. LombardiAbstract:The applicability of Raman spectroscopy and surface-enhanced Raman scattering (SERS) to the analysis of synthetic dyes commonly found in ballpoint inks was investigated in a comparative study. Spectra of 10 dyes were obtained using a dispersive system (633 nm, 785 nm lasers) and a Fourier transform system (1064 nm laser) under different analytical conditions (e.g., powdered pigments, solutions, thin layer chromatography [TLC] spots). While high fluorescence background and poor spectral quality often characterized the normal Raman spectra of the dyes studied, SERS was found to be generally helpful. Additionally, dye standards and a single ballpoint ink were developed on a TLC plate following a typical ink analysis procedure. SERS spectra were successfully collected directly from the TLC plate, thus demonstrating a possible Forensic Application for the technique.
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Application of Raman Spectroscopy and Surface‐Enhanced Raman Scattering to the Analysis of Synthetic Dyes Found in Ballpoint Pen Inks*
Journal of forensic sciences, 2009Co-Authors: B S Irina Geiman, Marco Leona, John R. LombardiAbstract:The applicability of Raman spectroscopy and surface-enhanced Raman scattering (SERS) to the analysis of synthetic dyes commonly found in ballpoint inks was investigated in a comparative study. Spectra of 10 dyes were obtained using a dispersive system (633 nm, 785 nm lasers) and a Fourier transform system (1064 nm laser) under different analytical conditions (e.g., powdered pigments, solutions, thin layer chromatography [TLC] spots). While high fluorescence background and poor spectral quality often characterized the normal Raman spectra of the dyes studied, SERS was found to be generally helpful. Additionally, dye standards and a single ballpoint ink were developed on a TLC plate following a typical ink analysis procedure. SERS spectra were successfully collected directly from the TLC plate, thus demonstrating a possible Forensic Application for the technique.