Double exponential model of corpse cooling under conditions of linearly varying ambient temperature
- Authors: Nedugov G.V.1
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Affiliations:
- Samara State Medical University
- Issue: Vol 7, No 4 (2021)
- Pages: 19-28
- Section: ORIGINAL STUDY ARTICLES
- URL: https://journals.rcsi.science/2411-8729/article/view/122411
- DOI: https://doi.org/10.17816/fm429
- ID: 122411
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Abstract
BACKGROUND: The main condition for the correctness of determining the postmortem interval by the method of thermometry of the deep tissues of the corpse is the constancy of the ambient temperature. This condition significantly limits the range of application of the method. The priority of thermometry of the core of the body in the diagnosis of prescription of death is explained by the slower cooling of deep tissues, which allows to increase the duration of the postmortem interval available for diagnosis, and less exposure to the influence of various random factors on the cooling process. The finite element models proposed recently can take into account almost all essential cooling conditions, including changes in ambient temperature, however, due to their high complexity, they require serious physical and mathematical training and technical skills, expensive software and postmortem computed tomography. For these reasons, they have not yet found wide application in expert practice.
In this article, a mathematical model of cooling the core of a corpse at a linearly varying ambient temperature is proposed.
AIMS: Construction a mathematical model of cooling the core of a corpse based on the Marshall-Hoare phenomenological law under conditions of linearly varying external temperature, to find a numerical algorithm for solving the model and to develop a computer program that implements it.
MATERIAL AND METHODS: A direct analytical modeling of the corpse cooling under conditions of linearly varying ambient temperature was carried out, performed on the basis of the Marshall-Hoare phenomenological cooling law and focused on solving the problem of determination of the postmortem interval by rectal or cranioencephalic temperature.
RESULTS: A mathematical model of cooling the core of a corpse under conditions of linearly varying ambient temperature has been developed. The chord method is proposed as a numerical algorithm for solving this model. The developed mathematical model and an iterative algorithm for its solution, as well as procedures for calculating interval estimates of the postmortem interval, are implemented in the C# language in the format of the Warm Bodies MHNH computer program.
CONCLUSIONS: It is advisable to use the proposed model and the program implementing it in forensic medical expert practice when determining the postmortem interval by the rectal or cranioencephalic temperature of a corpse in conditions of linearly varying ambient temperature.
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##article.viewOnOriginalSite##About the authors
German V. Nedugov
Samara State Medical University
Author for correspondence.
Email: nedugovh@mail.ru
ORCID iD: 0000-0002-7380-3766
SPIN-code: 3828-8091
Scopus Author ID: 25947646500
ResearcherId: ABH-5590-2020
MD, Dr. Sci. (Med.), Associate Professor
Russian Federation, 89 Chapaevskaya street, Samara, 443099References
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