POST-MORTEM INTERVAL ESTIMATION BY CEREBRO-SPINAL FLUID FILMS POLARIZATION IMAGES OPTICAL STRUCTURE CHANGING

INTRODUCTION: Post-mortem interval (PMI) estimation has been and remains one of the main issues of forensic medicine. Complex photometric, polarization, and correlation techniques of biological tissue (BT) structure are crucial in this area.OBJECTIVES: The purpose of this study is to develop and test two-dimensional Stokes-polarimetric mapping of biological layers to evaluate the accuracy of PMI assessments using statistical analysis of post-mortem changes and dynamics of the coordinate distributions for the polarization ellipticity (PE) images of polycrystalline films of liquor (PFL). Coordinate distributions of polarization ellipticity (PE) image values were estimated for each sample of PFL in the optical arrangement of the Stokes polarimeter using the method of two-dimensional distributions of Stokes-parameters.RESULTS: The most sensitive statistics to the post-mortem manifestations in terms of changes to liquor polycrystalline optical networks were those for the 3rd and 4th order. They characterized asymmetry and kurtosis (peak sharpness) of coordinate distributions for polarization ellipticity images of polycrystalline films of liquor. The optimal interval was 32 hours, with accuracy of 60 min, from the method of two-dimensional Stokes-polarimetric mapping used.

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POST-MORTEM INTERVAL ESTIMATION USING POLYCRYSTALLINE CEREBROSPINAL FLUID FILMS TWO-DIMENSIONAL CARTOGRAPHY OF MUTUAL LASER POLARIZATION DISTRIBUTION LEVELS

CBU International Conference Proceedings ◽

10.12955/cbup.v6.1267 ◽

2018 ◽

Vol 6 ◽

pp. 892-897

Author(s):

Marta Garazdiuk ◽

Oleh Wanchuliak ◽

Oleksandr Pavlyukovich ◽

Natalia Pavlyukovich ◽

Oleksandr Garazdiuk

Keyword(s):

Cerebrospinal Fluid ◽

Large Scale ◽

Interval Estimation ◽

Diagnostic Methods ◽

Two Dimensional ◽

Post Mortem ◽

Polycrystalline Films ◽

Fluid Films ◽

Microscopic Images ◽

Post Mortem Interval

Post-mortem interval estimation is one of the most important issues in forensic practice. Optical diagnostic methods of biological tissue structure assessment are perspective in this area.The objects of investigation are polycrystalline films of cerebrospinal fluid, taken from 64 corpses with accurately known times of death and 15 healthy volunteers.The method of two-dimensional stokes-polarimetric mapping of distributions of a complex degree of mutual polarization with spatial-frequency filtration of microscopic images of cerebrospinal fluid films in the time monitoring of post-mortem changes in optical manifestations of polycrystalline networks has been tested in order to estimate the post-mortem interval. The most sensitive post-mortem changes in the optical manifestations of polycrystalline cerebrospinal fluid networks are revealed - statistical moments of the third and fourth orders that characterize the asymmetry and the excess (severity of the peak) of the distributions of values of the complex degree of mutual polarization of large-scale components of cerebrospinal fluid polycrystalline films microscopic images.An interval of 48 hours with the accuracy of the post-mortem interval estimation in ± 30 minutes were established by the method of two-dimensional mapping of distributions of the values of a complex degree of mutual polarization of large-scale component of cerebrospinal fluid films microscopic images.

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Post-mortem interval estimation by laser-induced fluorescence of polycrystalline cerebro-spinal fluid films images

Forensic-medical examination ◽

10.24061/2707-8728.2.2016.7 ◽

2016 ◽

pp. 32-38

Author(s):

Marta Garazdiuk

Keyword(s):

Short Range ◽

Interval Estimation ◽

Statistical Processing ◽

Laser Induced Fluorescence ◽

Diagnostic Methods ◽

Postmortem Changes ◽

Two Dimensional ◽

Post Mortem ◽

Fluid Films ◽

Post Mortem Interval

There are many new optical diagnostic methods (photometric, polarization and correlation techniques) of biological tissue structure assessment, which are the most perspective in post-mortem interval determination. The purpose of the work. Development and testing of the two-dimensional Stokes-polarimetric mapping of biological layers own fluorescence to evaluate accuracy of the post-mortem interval (PMI) assessment using statistical analysis of postmortem changes dynamics of the coordinate distributions values of polycrystalline films of liquor (PFL) images laser-induced fluorescence polarization intensity (LIFPI). Materials and methods. Objects of investigation are PFL, taken in 72 corpses with accurately known time of death and 20 healthy volunteers. The cause of the death was cardiovascular accident. Coordinate distributions of LIFPI image values were determined for each sample of PFL in the optical arrangement of the Stokes polarimeter in short-range spectrum of optical radiation. The value of statistical points 1 - 4 th order was perfomed for each two-dimensional distribution of PFL images LIFPI values. Statistical processing of the calculated values of set of points that characterize the LIFPI distributions was carry out. The depending on the time change of the most sensitive points of statistical values were built. Results and conclusions. Two-dimensional Stokes-polarimetric mapping distributions LIFPI of PFL images may be used in determination of the PMI. Statistical points of the first and fourth order are the most sensitive PFL optical values to evaluate postmortem changes by short-range fluorescence.

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COMPARATIVE ANALYSIS OF LASER POLARIMETRY METHODS OF POLYCRYSTALLINE FILMS OF CEREBROSPINAL FLUID FOR POST-MORTEM INTERVAL ESTIMATION

CBU International Conference Proceedings ◽

10.12955/cbup.v7.1445 ◽

2019 ◽

Vol 7 ◽

Author(s):

Marta Garazdiuk ◽

Viktor Bachynskіy ◽

Oleh Vanchuliak ◽

Oleksandr Garazdiuk ◽

Yuliya Sarkisova

Keyword(s):

Cerebrospinal Fluid ◽

Interval Estimation ◽

Accurate Estimation ◽

Time Interval ◽

Two Dimensional ◽

Post Mortem ◽

Polycrystalline Films ◽

Technological Support ◽

Post Mortem Interval ◽

Stokes Polarimetry

Obtaining the most accurate information about an object during its evaluation is one of the most urgent tasks of current forensic medical examination. That is why the application of new technologies in forensic medical expertise becomes an integral part of the technological support of forensic examination institutions. Purpose: To compare the effectiveness of cerebrospinal fluid polycrystalline films, microscopic images, two-dimensional Stokes-polarimetry, and autofluorescent polarimetry in post-mortem interval estimation over long- and short-term time intervals. Material and methods. The object of the study is cerebrospinal fluid donated from 70 corpses (experimental group) and 20 living persons (control group). Methods used: two-dimensional Stokes-polarimetry, autofluorescent polarimetry. Results: Quantitative characteristics of the cerebrospinal fluid’s polycrystalline films statistical moments allows us to establish relations between them and the duration of the post-mortem interval at a significant time interval. However, this method does not consider the morphology of the film of the cerebrospinal fluid and its coordinate structure. In contrast to this method, fluorescence microscopy considers the biochemical composition of the biological fluid and carries information about the concentration of molecular complexes of proteins, NADH, flavins, porphyrins, etc. In the early post-mortem period, changes in the cerebrospinal fluid begin precisely with changes in the concentration of biochemical compounds, and crystalline changes are secondary, so it can be argued that this method is most effective for diagnosing the progression of the time in the first hours after death. Conclusions: Fluorescent laser polarimetric methods allow accurate estimation of the postmortem interval during the first hours after death. While, the polarization methods is more effective during the long-term periods of time, but has less precision.

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Post-Mortem Interval Estimation Based on Insect Evidence: Current Challenges

Insects ◽

10.3390/insects12040314 ◽

2021 ◽

Vol 12 (4) ◽

pp. 314

Author(s):

Szymon Matuszewski

Keyword(s):

Forensic Entomology ◽

Interval Estimation ◽

Review Literature ◽

Error Rates ◽

Post Mortem ◽

Post Mortem Interval ◽

Research Areas ◽

Pmi Estimation

During death investigations insects are used mostly to estimate the post-mortem interval (PMI). These estimates are only as good as they are close to the true PMI. Therefore, the major challenge for forensic entomology is to reduce the estimation inaccuracy. Here, I review literature in this field to identify research areas that may contribute to the increase in the accuracy of PMI estimation. I conclude that research on the development and succession of carrion insects, thermogenesis in aggregations of their larvae and error rates of the PMI estimation protocols should be prioritized. Challenges of educational and promotional nature are discussed as well, particularly in relation to the collection of insect evidence.

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The effect of cyanide exposure to larvae weight for post mortem interval estimation

INTERNATIONAL JOURNAL OF ETHICS TRAUMA & VICTIMOLOGY ◽

10.18099/ijetv.v2i1.11133 ◽

2016 ◽

Vol 2 (1) ◽

Author(s):

Idha Arfianti Wiraagni ◽

Yudha Nurhantari ◽

Siti Rahmah Umniyati

Keyword(s):

Life Cycle ◽

Interval Estimation ◽

Wistar Rat ◽

Control Group ◽

Post Mortem ◽

Post Mortem Interval ◽

Cyanide Group ◽

Human Cadavers ◽

Pmi Estimation ◽

Third Instar Larvae

Flies are one type of insect, which decompose the organic component in animals, and human cadavers. Therefore, the insects can be used to help the investigators related to human law. One of the methods to determine Post Mortem Interval [PMI] was by identifying the insects that come in the decay process. Some chemicals can affect the development of the insect and its life cycle. Cyanide is widely used to commit murder in Indonesia. The effect of cyanide on the development and life cycle of insects is a very interesting field to study. The purpose of this study was to determine the effect of cyanide exposure to larvae weight for PMI estimation. This research was an experimental research that used larvae of Wistar rat carcass. The control group was killed by neck dislocation, while experimental group were killed by oral lethal doses of cyanide. Data were obtained from the measurement and examination of larvae, started from the 1st day until 4th day after death. Chrysomya, Sarcophaga, and Lucilia larvae were identified from this study. Sarcophaga larvae first appeared and next day followed by Chrysomya and Lucilia. There were significant differences in Chrysomya larvae weight. There were Chrysomya third instar larvae on the 4th day on cyanide group, with 56.4±16.8 mg of weight. There were Chrysomya third instar larvae on the 4th day on control group, with 30.4±5.5 mg of weight. The differences of larvae’s weight, among Sarcophaga and Lucilia larvae, could not be determined because there were not enough samples. Chrysomya third instar larvae of cyanide group significantly heavier than control group on 4th day. The differences of larvae weight, among Sarcophaga and Lucilia larvae, could not be determined because there were not enough samples.

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Time since deaht estimation by the method of the three- dimensional-frequency polarizing maping filtering of polycrystalline cerebro-spinal fluid films images

Forensic-medical examination ◽

10.24061/2707-8728.1.2017.15 ◽

2017 ◽

pp. 65-73

Author(s):

Marta Garazdiuk

Keyword(s):

Three Dimensional ◽

Stokes Parameters ◽

Small Scale ◽

Time Since Death ◽

Two Dimensional ◽

Post Mortem ◽

Polycrystalline Films ◽

Polarization Azimuth ◽

Optimal Interval ◽

Death Determination

There are many new methods ware researched in recent years for time since death estimation and laser polarimetric techniques are one of the most perspectiv of them. Thay have demonstrated the high accuracy and objectivity of biological tissue investigation for various intervals of post-mortem period. The purpose of the work. The post-mortem interval establishment by statistical analysis of the dynamics changes of coordinate distributions of values polarization azimuth (PA) of the polycrystalline films of liquor (PFL) using the three-dimensional-frequency filtering method of biological multiscale layers investigation. Materials and methods. Objects of investigation are PFL, taken in 67 corpses with accurately known time of death and 6 healthy volunteers. Coordinate distributions of PA image values were estimated for each sample of PFL in the optical arrangement of the Stokes polarimeter using the method of two-dimensional distributions of Stokes-parameters measurement. The value of statistical points of the 1 - 4 th order was perfomed for each two-dimensional distribution of PFL images PE values. Statistical processing of the calculated values of set of points that characterize the PA distributions within representative sampling was carry out. The depending on the time change of the most sensitive points of statistical values were built to achieve values stabilization. Results and conclusions. Optimal interval in 30 hours and the accuracy of the time since death determination 80 min for the large-scale component of polycrystalline films of liquor and optimal interval in 14 hours and the accuracy of the time since death determination 30 min for the small-scale component of polycrystalline films of liquor were established by the method of two- dimensional Stokes-polarimetric mapping of liquor images polarization azimuth values distribution.

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Caspase 9 and Caspase 3 Immunohistochemical Pattern in Skeletal and Cardiac Muscles at Different Times after Death: An Experimental Study on PMI Estimation

Diagnostics ◽

10.3390/diagnostics11061062 ◽

2021 ◽

Vol 11 (6) ◽

pp. 1062

Author(s):

Cristina Mondello ◽

Chiara Stassi ◽

Letteria Minutoli ◽

Gennaro Baldino ◽

Angela Alibrandi ◽

...

Keyword(s):

Caspase 3 ◽

Potential Role ◽

Interval Estimation ◽

Immunohistochemical Analysis ◽

Post Mortem ◽

Caspase 9 ◽

Post Mortem Interval ◽

Cardiac Muscles ◽

Preliminary Activation ◽

Pmi Estimation

(1) Background: The estimation of the post mortem interval (PMI) is a challenge for forensic pathologists because data emerging from methods commonly applied are not always conclusive, since several conditions exist that may affect the reliability of these parameters. Thus, new approaches have been proposed to overcome such a limit. In recent years, several studies have been performed on proteins analyzing their expression/degradation patterns in relation to the progressing of the post mortem interval. (2) Methods: The immunoreactivity patterns of two apoptosis mediators—Caspase 9 and Caspase 3—have been tested in order to evaluate their potential role as markers of the post mortem interval. The immunohistochemical analysis was performed on samples of skeletal and cardiac muscles obtained from rats at 0, 4, 8, 12, 24 and 72 h after death. (3) Results: The observed immunoreactivity patterns of both Caspase 9 and Caspase 3 showed a significant correlation with increasing post mortem interval either in skeletal or cardiac muscles, while the comparison of the immunoreactivity patterns of the two apoptotic mediators within each tissue appeared consistent with a preliminary activation of the “initiator” Caspase 9, which, in turn, subsequently activates the “executioner” Caspase 3. (4) Conclusion: The different expressions and decrease immunohistochemically observed on both caspases with progressing PMI support the usefulness of the combined analysis for post mortem interval estimation.

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