دانلود رایگان مقاله انگلیسی بهبود دمای صحنه جرم در پرونده حشره شناسی قانونی - الزویر 2017

Abstract

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.

4. Conclusion

The focus of this paper was to determine the relationship between ambient temperatures (measured by dataloggers in sun, shelter and SS) and ‘bodies’ (pig heads) in a similar range of environments. This study has clearly demonstrated the complexity of estimating accurate and precise temperatures experienced by insects feeding on a body, and the consequences of utilising inaccurate data for minPMI estimation models. Caution is advised regarding data logger placement at crime scenes, especially to measure the temperature of a body that has been lying in direct sunlight, when measurements of ambient temperatures, from unshielded data loggers or those in a SS, do not always reflect body temperatures. Although the placement of a data logger in a SS to estimate body temperatures showed no clear advantage over placing the data logger directly into the environment, it is recommended that a SS is used where possible and practical to comply with WMO recommendations [33]. For partially sheltered and sheltered bodies the differences between body temperatures and those of data loggers placed in the same situation are small; however, it is recommended that data loggers should be placed as close to and in as similar conditions as to where the body was found as possible, e.g., avoiding placement in front of windows if the body is shaded indoors.

The results of this study mark a necessary starting point for further research that is needed in this area to increase the accuracy of minPMI estimations, thereby leading to greater reliability of forensic entomology evidence presented in court.