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291.
Anagen hairs are in the active growth phase, and when forcefully removed, may contain an intact root or sheathing. The hair root or sheathing is a source of nucleic DNA and can be amplified using direct PCR. Human identification STR kits are optimised to a small range of input DNA for PCR. Anagen hairs are unable to be quantified prior to amplification and can exhibit characteristics of an over-loaded DNA sample when analysed. The aim of this study was to optimise direct PCR for anagen hair sampling. Two separate modifications to the downstream processes were carried out in order to determine the most effective method at minimising PCR artefacts. Decreasing the cycle number from the standard 29 cycles to 27 cycles when using the NGM™ kit displayed the best results for this method. However, decreasing the cycle number may increase allelic drop-out and would be costly for laboratories to perform an in-house validation. Diluting the PCR product during electrophoresis analysis minimises the effects of PCR artefacts in the same way decreasing the cycle number does. Diluting the PCR product is the most cost-effective method and does not increase the chance of allelic drop-out.  相似文献   
292.
The House of Commons select committees witnessed some of the most constructive political theatre of the 2010‐2015 Parliament. Recall Rupert Murdoch's public contrition, Margaret Hodge's assault on MNC tax evasion and Keith Vaz's timely interrogations of G4S, etc. The committees also embraced social media and adopted public engagement as a key task. These developments all reflect a newly emboldened system. In recent months, four reports have been published which reflect on these developments. They also look forward to the further substantial development of committee activity. The system thus sets sail with an abundance of specific suggestions, including ideas that could have far wider and more far‐reaching democratic implications.  相似文献   
293.
《Science & justice》2022,62(3):284-287
Forensic DNA profiling is a globally accepted method for human identification, however, obtaining full DNA profiles from trace DNA can be challenging. The optimal recovery of DNA from trace DNA swabs is therefore crucial. Methods for extracting DNA from swabs often make use of a spin basket combined with a centrifugation step, to enhance the release of cells from the swab prior to DNA extraction. The NucleoSpin® Forensic Filter (Macherey-Nagel, Düren) is a type of spin basket, but it has not been thoroughly assessed on trace DNA samples. This study aimed to assess if the inclusion of the NucleoSpin® Forensic Filter significantly improved DNA recovery and DNA profiling success from cotton and flocked swabs used to collect trace DNA and buccal cells (control). Buccal cells and trace DNA samples were collected from 25 volunteers using each swab type (cotton and flocked) in duplicate. DNA was extracted from the samples using the NucleoSpin® DNA Forensic kit, one set with, and the other set without, NucleoSpin® Forensic Filters. DNA concentration was assessed using real time PCR, and DNA profiling was done using the PowerPlex® ESX 16 system. The inclusion of the NucleoSpin® Forensic Filters significantly improved DNA concentration for buccal cells that were collected using flocked swabs (p = 0.035). However, no significant differences were noted for trace DNA samples for either swab type. There was also no significant difference in DNA profiling success when NucleoSpin® Forensic Filters were used, regardless of swab and sample type. These results may be helpful for laboratories that are considering the NucleoSpin® Forensic Filters in the DNA extraction workflow, particularly for trace DNA samples.  相似文献   
294.
Analysis of impurities in seized MDMA tablets can be used to determine the synthesis method used and to identify links among exhibits. However, no standardized method exists to generate impurity profiles, limiting comparisons among different laboratories. This research investigated the effect of extraction procedure and gas chromatography temperature program on the resulting impurity profiles. Five exhibits were extracted using liquid–liquid extraction (LLE) and headspace solid‐phase microextraction (HS‐SPME), then analyzed using two different temperature programs. Profiles were statistically assessed using principal components analysis. While LLE was more reproducible, more compounds were extracted using HS‐SPME, thus providing more informative chemical profiles. The longer temperature program (53 min vs. 36 min) allowed greater discrimination of exhibits, due to improved precision as a result of an extended hold time (12 min). This research further highlights the need for standardized extraction and analysis procedures to allow comparison of chemical profiles generated in different laboratories.  相似文献   
295.
Automated profiling of groups and individuals is a common practice in our information society. The increasing possibilities of data mining significantly enhance the abilities to carry out such profiling. Depending on its application, profiling and data mining may cause particular risks such as discrimination, de-individualisation and information asymmetries. In this article we provide an overview of the risks associated with data mining and the strategies that have been proposed over the years to mitigate these risks. From there we shall examine whether current safeguards that are mainly based on privacy and data protection law (such as data minimisation and data exclusion) are sufficient. Based on these findings we shall suggest alternative policy options and regulatory instruments for dealing with the risks of data mining, integrating ideas from the field of computer science and that of law and ethics.  相似文献   
296.
Poaching is a crime that occurs worldwide and can be extremely difficult to investigate and prosecute due to the nature of the evidence available. If a species is protected by international legislation such as the Convention on International Trade in Endangered Species of Wild Fauna and Flora then simply possessing any part of that species is illegal. Previous studies have focused on the identification of endangered species in cases of potential poaching. Difficulties arise if the poached animal is not endangered. Species such as deer have hunting seasons whereby they can legally be hunted however poaching is the illegal take of deer, irrespective of season. Therefore, identification of deer alone has little probative value as samples could have originated from legal hunting activities in season. After a deer is hunted it is usual to remove the innards, head and lower limbs. The limbs are removed through manual force and represent a potential source of human touch DNA.We investigate the potential to recover and profile human autosomal DNA from poached deer remains. Samples from the legs of ten culled deer were obtained (40 in total) using minitapes. DNA from samples was extracted, quantified and amplified to determine if it would be possible to recover human STR profiles.Low quantification data led to the use of an extended PCR cycling protocol of 34 cycles. Samples from seven deer amplified, however some samples were excluded from further analysis due to ‘drop in’ alleles or the low level of successfully amplified loci. Samples from five deer could be further analysed and gave match probabilities ranging from 6.37 × 10− 3 to 9.53 × 10− 11.This study demonstrates the potential of recovering human touch DNA from poached animal remains. There is the potential for this test to be used in relation to other species of poached remains or other types of wildlife crimes. This is the first time, to our knowledge, that human STR profiling has been successfully applied to touch DNA in regards to simulated wildlife crime.  相似文献   
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