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In this jurisdiction, scene and laboratory forensic services are delivered within short time frames with a focus on providing impartial scientific and investigative services to assist criminal investigations conducted by police. https://www.selleckchem.com/products/abt-199.html The current dataset was highly skewed in terms of criminal justice outcomes and was not suitable for conducting the planned statistical analyses. Nonetheless, the pattern of findings obtained suggested that the inclusion of forensic evidence which supported the prosecution of arson may be associated with an increased likelihood of suspects being charged and defendants found guilty. Examination of the decision-making process of the forensic fire examiners has provided insight into the variety of evidence that is considered by forensic experts in reaching the important conclusion about the origin and cause of structural fires.The recovery of three-dimensional footwear impressions at crime scenes can be a challenge but can also yield important investigative data. Traditional methods involve casting 3D impressions but these methods have limitations the trace is usually destroyed during capture; the process can be time consuming, with a risk of failure; and the resultant cast is bulky and therefore difficult to share and store. The use of Structure from Motion (SfM) photogrammetry has been used widely to capture fossil footprints in the geological record and while there is a small body of work advocating its use in forensic practice the full potential of this technique has yet to be realised in an operational context. The availability of affordable software is one limiting factor and here we report the availability of a bespoke freeware for SfM recovery and subsequent analysis of for footwear evidence (DigTrace). Our aim here is not to provide a rigorous comparison of SfM methods to other recovery methods, but more to illustrate the potential while also documenting the typical workflows and potential errors associated with an SfM based approach. By doing so we hope to encourage further research, experimentation and ultimately adoption by practitioners.Glass is a common type of physical evidence in forensic science. Broken glass recovered from a suspect may have similar physical characteristics to glass collected at a crime scene and therefore can be used as evidence. Statistical treatment of this evidence involves computing a measure of the weight of evidence. This may be done in a Bayesian framework that incorporates information from the circumstances of the crime. One of the most crucial quantities in this calculation is the assessment of the relative rarity of the characteristics of the glass, essentially the probability distribution used to model the physical characteristics of recovered glass. Typical characteristics used in casework are the elemental composition of glass and the refractive index measurement. There is a considerable body of scientific literature devoted to the modelling of this information. For example a kernel density estimation has been used to model the background population of glass based on the refractive index measurement and a multivariate Gaussian finite mixture model has been used to model the elemental composition of glass. In this paper, we present an alternative approach, the Dirichlet Process Mixture Model, to model the glass refractive index measurement in a Bayesian methodology. A key advantage is that using this method allows us to model the probability density distribution of refractive index measurements in a more flexible way.When a body is decomposed, hard tissues such as teeth may provide the only DNA source for human identification. There is currently no consensus as to the best DNA extraction method, and there is a lack of empirical data regarding tooth morphotype and condition that may impact DNA recovery. Therefore, this study sought to investigate which variables significantly improved DNA concentration, integrity and profiling success. A total of 52 human teeth were assessed, representing all tooth morphotypes from three deceased individuals. DNA was extracted using both the QIAamp® DNA Investigator Kit and the phenol-chloroform method. DNA concentration and degradation index were assessed using real time PCR, prior to conventional DNA profiling. Contrary to international guidelines promoting the use of molars, DNA profiling from molars was the least successful, with premolars, followed by canines, performing the best. The presence of fillings reduced the DNA quantity and quality obtained and may explain the poor performance of molars. DNA from the maxillae were significantly less degraded when the QIAamp® was used, although this did not influence DNA profiling success. A significant increase in DNA concentration, integrity and profiling success was observed in diseased teeth (periodontitis) compared to those without disease. This may be due to increased white blood cell presence at the site. There was no significant difference in DNA profiling success between the two DNA extraction methods. However, different teeth yielded failed DNA profiles for each extraction method, suggesting that repeated attempts, using alternative DNA extraction methods, is recommended. The recovery of additional DNA profiling information from degraded samples may help to ultimately reduce the burden of unidentified human remains.Identification of incinerated human remains may rely on genetic analysis of burned bone which can prove far more challenging than fresh tissues. Severe thermal insult results in the destruction or denaturation of DNA in soft tissues, however genetic material may be preserved in the skeletal tissues. Considerations for DNA retrieval from these samples include low levels of exogenous DNA, the dense, mineralised nature of bone, and the presence of contamination, and qPCR inhibitors. This review collates current knowledge in three areas relating to optimising DNA recovery from burned bone 1) impact of burning on bone and subsequent effects on sample collection, 2) difficulties of preparing burned samples for DNA extraction, and 3) protocols for bone decalcification and DNA extraction. Bone decalcification and various DNA extraction protocols have been tested and optimised for ancient bone, suggesting that prolonged EDTA (Ethylenediaminetetraacetic acid) demineralisation followed by solid-phased silica-based extraction techniques provide the greatest DNA yield.