scholarly journals Diagnostic possibilities of accurate determination of the time since death on the concentration of electrolytes in the vitreous body of the human eye

2021 ◽  
pp. 79-85
Author(s):  
Yuliia Sarkisova
Keyword(s):  
Accurate Determination ◽  
Vitreous Body ◽  
Statistical Processing ◽  
Test Material ◽  
Main Task ◽  
Time Since Death ◽  
Exclusion Criteria ◽  
Cardiovascular Pathology ◽  
Human Eye

In this paper the results of modern scientific researches are analyzed and the possibilities of the method of establishing the amount of K+ and Na+ in the vitreous body (VB) of a person for solving problems of practical forensic medicine are studied. The aim of the work. To investigate the possibilities of accurately establishing the time since death (TSD) by determining the amount of electrolytes (K+ and Na+) of human VB. Materials and methods. VB samples from 120 deaths due to cardiovascular pathology (exclusion criteria: eyeball injuries, traumatic brain injury, exogenous intoxications) were studied. The study of the test material was performed on an analyzer of electrolytes and gases ROCHE COBAS B121. The main task was to analyze and establish the dependence of the change in the amount of K+ and Na+ of the VB on the TSD. Statistical processing of the obtained results was performed using Statistica software. Results. In all cases, on average in the first 6 hours, its amount was 7,4 mmol/l, after 6-12 hours – 9,8 mmol/l, after 12-18 hours – 12,1 mmol/l, after 18-24 hours – 16,5 mmol/l, after 24-36 hours – 20,2 mmol/l, after 36-48 hours – 25,3 mmol/l. The amount of Na+ ranged from 120 to 200 mmol/l. Conclusions. It is established that the number of electrolytes of the VB of the human eye naturally changes with increasing postmortem interval, which allows to use this technique to determine the TSD. In particular, the accuracy of setting the DNS by the number of K+ – 4-6 hours between 1 and 18 hours after death. There is an increase in the range of accuracy at a later date of the TSD.

scholarly journals DIAGNOSTIC POSSIBILITIES OF ANALYSIS OF THE MAP OF LINEAR BIREFRINGENCE OF THE CRYSTAL FRACTION OF VITREOUS BODY FOR ACCURATE DETERMINATION OF THE TIME SINCE DEATH

2020 ◽  
Vol 1 ◽  
pp. 82-89
Author(s):  
Yuliia Sarkisova ◽  
Viktor Bachynskіy ◽  
Alina Palamar ◽  
Nadya Palibroda ◽  
Maryna Patratii
Keyword(s):  
Scientific Evidence ◽  
Accurate Determination ◽  
Vitreous Body ◽  
Linear Birefringence ◽  
Time Since Death ◽  
Polycrystalline Structure ◽  
Polarization Tomography ◽  
Sensitivity Range ◽  
Crystal Fraction ◽  
Definition Of

Introduction: This paper discusses the possibility of polarization microscopic tomography of polycrystalline structure of vitreous body (VB) for use in forensics and in determining the time since death (TSD). Objectives: The purpose of this study was to develop a new set of forensic criteria to enhance the functionality of the high-precision definition of TSD over a long period of time according to polarization microscopic tomography of the polycrystalline structure of the VB of the human eye by statistical and wavelet analysis. Results: We obtained the numerical values of the change in the magnitude of the statistical moments of the 1-4 orders, which characterize the coordinate distributions of the magnitude of the linear birefringence (LB) of the polycrystalline component of the VB by the magnitude of the TSD. The results from our research illustrate the differences between the optical anisotropy of fibrillar collagen networks of VB layers with different TSD. The sensitivity range (36 hours) and accuracy (15 minutes) of the method of polarization tomography of the LB distributions of the polycrystalline component of the VB layers in the determined TSD were established. Conclusion: These results confirm the experimental processes outlined accurately determine the time of death. In turn, will provide scientific evidence, specifications thereof, and objective expert opinion.

A quantitative approach to inner shell losses

1978 ◽  
Vol 36 (1) ◽  
pp. 526-527 ◽  
Author(s):  
R.D. Leapman ◽  
P. Rez ◽  
D.F. Mayers
Keyword(s):  
Energy Transfer ◽  
Cross Section ◽  
Cross Sections ◽  
Accurate Determination ◽  
Background Intensity ◽  
Core Excitation ◽  
Quantitative Basis ◽  
Cross Section Differential ◽  
Bound Electrons

Microanalysis by EELS has been developing rapidly and though the general form of the spectrum is now understood there is a need to put the technique on a more quantitative basis (1,2). Certain aspects important for microanalysis include: (i) accurate determination of the partial cross sections, σx(α,ΔE) for core excitation when scattering lies inside collection angle a and energy range ΔE above the edge, (ii) behavior of the background intensity due to excitation of less strongly bound electrons, necessary for extrapolation beneath the signal of interest, (iii) departures from the simple hydrogenic K-edge seen in L and M losses, effecting σx and complicating microanalysis. Such problems might be approached empirically but here we describe how computation can elucidate the spectrum shape.The inelastic cross section differential with respect to energy transfer E and momentum transfer q for electrons of energy E0 and velocity v can be written as

Fast calibration of CBED patterns for quantitative analysis

1993 ◽  
Vol 51 ◽  
pp. 674-675
Author(s):  
M.A. Gribelyuk ◽  
M. Rühle
Keyword(s):  
Reciprocal Lattice ◽  
Accurate Determination ◽  
Incident Beam ◽  
Crystal Thickness ◽  
Structure Model ◽  
Beam Direction ◽  
Transmitted Beam ◽  
Reciprocal Vector ◽  
On Line

A new method is suggested for the accurate determination of the incident beam direction K, crystal thickness t and the coordinates of the basic reciprocal lattice vectors V1 and V2 (Fig. 1) of the ZOLZ plans in pixels of the digitized 2-D CBED pattern. For a given structure model and some estimated values Vest and Kest of some point O in the CBED pattern a set of line scans AkBk is chosen so that all the scans are located within CBED disks.The points on line scans AkBk are conjugate to those on A0B0 since they are shifted by the reciprocal vector gk with respect to each other. As many conjugate scans are considered as CBED disks fall into the energy filtered region of the experimental pattern. Electron intensities of the transmitted beam I0 and diffracted beams Igk for all points on conjugate scans are found as a function of crystal thickness t on the basis of the full dynamical calculation.

Computer-Assisted High-Re Solution TEM

1990 ◽  
Vol 48 (1) ◽  
pp. 162-163
Author(s):  
F.A. Ponce ◽  
H. Hikashi
Keyword(s):  
Signal To Noise Ratio ◽  
Accurate Determination ◽  
Computer Software ◽  
Video Camera ◽  
Image Contrast ◽  
Objective Lens ◽  
Computer Assisted ◽  
Optical Parameters ◽  
Astigmatism Correction

The determination of the atomic positions from HRTEM micrographs is only possible if the optical parameters are known to a certain accuracy, and reliable through-focus series are available to match the experimental images with calculated images of possible atomic models. The main limitation in interpreting images at the atomic level is the knowledge of the optical parameters such as beam alignment, astigmatism correction and defocus value. Under ordinary conditions, the uncertainty in these values is sufficiently large to prevent the accurate determination of the atomic positions. Therefore, in order to achieve the resolution power of the microscope (under 0.2nm) it is necessary to take extraordinary measures. The use of on line computers has been proposed [e.g.: 2-5] and used with certain amount of success.We have built a system that can perform operations in the range of one frame stored and analyzed per second. A schematic diagram of the system is shown in figure 1. A JEOL 4000EX microscope equipped with an external computer interface is directly linked to a SUN-3 computer. All electrical parameters in the microscope can be changed via this interface by the use of a set of commands. The image is received from a video camera. A commercial image processor improves the signal-to-noise ratio by recursively averaging with a time constant, usually set at 0.25 sec. The computer software is based on a multi-window system and is entirely mouse-driven. All operations can be performed by clicking the mouse on the appropiate windows and buttons. This capability leads to extreme friendliness, ease of operation, and high operator speeds. Image analysis can be done in various ways. Here, we have measured the image contrast and used it to optimize certain parameters. The system is designed to have instant access to: (a) x- and y- alignment coils, (b) x- and y- astigmatism correction coils, and (c) objective lens current. The algorithm is shown in figure 2. Figure 3 shows an example taken from a thin CdTe crystal. The image contrast is displayed for changing objective lens current (defocus value). The display is calibrated in angstroms. Images are stored on the disk and are accessible by clicking the data points in the graph. Some of the frame-store images are displayed in Fig. 4.

The New Swedish Cyprus Expedition 2010. Excavations at Dromolaxia Vizatzia/Hala Sultan Tekke. Preliminary results

2011 ◽  
Vol 4 ◽  
pp. 69-98 ◽  
Author(s):  
Peter M. Fischer ◽  
Patrik Klingborg ◽  
Fanny Kärfve ◽  
Fredrika Kärfve ◽  
C. Hagberg ◽  
...  
Keyword(s):  
Ground Penetrating Radar ◽  
Main Task ◽  
Phase 2 ◽  
The North ◽  
12Th Century ◽  
Area 6 ◽  
Recent Phase ◽  
The Rich ◽  
Ground Penetrating

Determination of the complete occupational sequence of the site, including investigation of pre-12th century levels which were thoroughly studied by P. Åström since the 1970s, is the main task of the planned project. During the course of the expedition (NSCE11) in spring 2010 a ground-penetrating radar survey (GPR) was carried out at Dromolaxia Vizatzia/Hala Sultan Tekke in Area 6, leading to the discovery of a large Late Cypriote complex. The compound is bordered to the north by a substantial wall, against which nine rooms (so far) could be exposed. Two occupational phases have been verified but there are indications of a third. The suggested functions of the various structures of the most recent phase are: living, working, storage and administration spaces. The rich find contexts point to the production of textiles and metal objects, and the locally produced pottery is generally of a high quality. There are also many imports, mainly from the Mycenaean sphere of culture. The locally produced vessels from Phase 2 include the “Creature krater” which is a masterpiece of a high artistic standard. Another piece of elevated artistry is the piece of a “Warrior vase”.

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