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Sampling of biological material for forensic examinations
Bartková, Viktória ; Vaněk, Daniel (advisor) ; Tomášek, Petr (referee)
This bachelor's thesis discusses the basic methods and procedures for securing biological material, subsequent analysis of which is an essential component in the process of investigating crime offences, but also mass fatality inccidents. Due to the risk of contamination and degradation of biological material, it is necessary to follow certain rules and procedures for secure sampling suitable for subsequent forensic examination. The main goal of securing a trace of biological material is to enable its DNA analysis, for which it is necessary to ensure a certain degree of integrity of the material itself as well as the nucleic acid. Stability can be achieved by using stabilizing agents that slow DNA degradation, allowing it to be analyzed immediately but also reexamined over time. Keywords: wildlife crime, forensic, DNA, species and individual identification, sampling
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The influence of tanning chemical agens on DNA degradation
Hebenstreitová, Kristýna ; Vaněk, Daniel (advisor) ; Novák, Jindřich (referee)
The illegal wildlife trade is currently on the rise, and it is becoming the fourth most lucrative sector of crime. The traded commodities of this sector are, for example, various animal artefacts from skins, teeth, scales, tusks, claws to whole animal bodies, as well as eggs of endangered birds (parrots and birds of prey) or amphibians and snakes. The rarer the species is, the higher the demand for it grows. Wildlife trade is regulated (among other things) under the international CITES convention (Convention on International Trade in Endangered Species of Wild Fauna and Flora). Proving that this convention has been violated, is complex process and can be very difficult to achieve. In many cases a DNA analysis of the artefact, is the only way to prove, that it originates from a protected animal species and not from a species with which it is legal to trade. This thesis deals with a specific type of animal artefact - tanned skins. With this type of biological material, it is often problematic to obtain amplifiable DNA (deoxyribonucleic acid). This thesis is investigating the influence of the chemicals used in the tanning process on the DNA degradation. Furthermore, it analyses, the influence of these substances on the inhibition of the polymerase chain reaction. The quantity of DNA is determined...
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The impact of chimerism in DNA-based forensic analysis
Kalousková, Martina ; Šimková, Halina (advisor) ; Vaněk, Daniel (referee)
The presence of two or more zygotically distinct lineages in a single person refers to chimerism. All types of chimerism have positive as well as negative impact on health of human chimeras. Both congenital and acquired chimerism must be taken into account in diagnostics, genetics but also in the forensic DNA analysis. This phenomenon has impact on the results of individual identification and kinship determination. With the forensic analysis it is possible to detect chimerism of people under investigation. Even though these situations are rare, some cases of wrong identification proving the consequences of the chimerism are recorded.
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Návrh silového členu simulátoru zátěže pro dlouhodobé zkoušky VTG aktuátoru
VANĚK, Daniel
The topic of diploma thesis is focused on the design of the life of the power member of the preparation with springs (the load simulator). The preparation is used for long-term testing of VTG (Variable Turbinen Geometrie) actuators. The diploma thesis follows the author's bachelor's thesis (Vaněk, 2019). The theoretical part is focused on the fatigue of the material, the geometry of the used springs, the decomposition of the test profile using the Rain flow method and the Matlab (interactive software). The practical part of that thesis deals with the analysis of the test profile, the calculation of the accumulation of damage and the statistical evaluation of the service life of the used springs.
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Biological age prediction using DNA analysis
Stokičová, Linda ; Vaněk, Daniel (advisor) ; Tomášek, Petr (referee)
Eye colour, hair colour and biogeographical origin can be predicted based on DNA analysis. This is used in forensic genetics when an unknown perpetrator leaves a biological material on a crime scene. Prediction of biological age is the subject of further research. Nowadays, there is no standardised model, which can be used for accurate prediction. The best option for biological age prediction is DNA methylation - stable epigenetic modification. Many markers have been evaluated. Methylation of these markers correlates with biological age positively or negatively. Methylation has tissue specificity, so one model cannot be applied on all types of tissues. Model for biological age prediction can be applied during investiganting of a criminal activity, when the identity of a person commiting a crime is unknown. Key words: methylation, chronological age, biological age, DNA analysis, forensic genetics
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Determination of mtDNA sequence variation in czech population for the usage in forensic genetics.
Řadová, Marie ; Coufalová, Pavla (advisor) ; Vaněk, Daniel (referee)
In forensic research and practice is used an analysis of nuclear DNA commonly. However, in some cases we can use only mitochondrial DNA. The mtDNA is maternally inherited and it is located in the each cell approximately in 500 copies. Barring mutation in special noncoding segments, the mtDNA sequence of siblings and all maternal relatives is identical. This unique haplotyp can be helpful in forensic cases, such as analyzing the remains of a missing person, where known maternal relatives can provide reference samples for direct comparison to the questioned mtDNA type. MtDNA is also very resistant to the external influences, so in the cases where the amount of extracted DNA is very small or degraded it is more likely that a DNA typing result can be obtained by typing mtDNA than by typing polymorphic markers found in nuclear DNA. If we want to have a certain probability to exclude or confirm the match of two samples, classify suspect or missing person into a population, we need some enough wide comparison by the population databases. Then we can study the frequencies of different haplotypes in particular population. The aim of this thesis is summery of history of DNA analysis, mtDNA sequencing and comparison of data available in published databases in the world and mainly in the Czech Republic. There is also...
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IS in identification genetics
Dorčáková, Terézia ; Vaněk, Daniel (advisor) ; Formanová, Dominika (referee)
DNA analysis serves as a highly efficient identification tool when the biological material to be identified is heavily damaged or does not carry sufficient morphological characteristics. It is employed for human, but also for non-human identification in numerous cases such as crime investigation and prevention, populational studies, kinship analysis, paternity testing, mass grave body recognition or endangered species rescue. For successful identification, it is necessary to collect and maintain DNA profile databases. Such databases hold records of people involved in criminal activity or sequences from non-human sources. This work intends to review how identification and kinship analysis using genetic material works. Next, the most important databases collecting DNA profiles are summarised. Although the benefits of such databases are vast, there are many ethical concerns about misuse of such private information. For convenient database queries, a dedicated set of command line tools has been implemented by the author. These are used for an exemplary species identification of an unknown sequence.
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CITES organisms and traditional Chinese medicine
Chromková, Dominika ; Vaněk, Daniel (advisor) ; Říhová, Pavla (referee)
The illegal trade of wildlife animal and plant species is one of the most lucrative crimes in the world. The driving force behind this unfair practice of threatening many species for survival is the largely increasing demand for raw materials used to prepare traditional Chinese medicine (TCM). Its medicinal preparations include, among others, organisms with which trade is prohibited or regulated under the CITES convention (the Convention on International Trade in Endangered Species of Wild Fauna and Flora). This international agreement clearly defines the rules of trade of wild species and products thereof, the violation of which is punishable on the basis of the legislation of a particular country. Easily standardized and accurate species identification techniques are needed to make more effective the prosecution of this type of crime. In my bachelor's thesis I am representing a summary and evaluation of DNA identification methods, which are based on the principle of hybridization, polymerase chain reaction or sequencing, including samples with degraded DNA or complex samples containing a mixture of different species. DNA barcoding is currently proven to be an optimal tool to detect the source organisms of Chinese medicine. The text is supplemented by the list of the most commonly confiscated...
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Návrh simulátoru zátěže pro dlouhodobé zkoušky VTG aktuátoru
VANĚK, Daniel
This bachelor thesis is focused on the design of simulator for power load. The simulator is used for long-term actuator testing at Robert Bosch Czech Budweis. At firtst is shown turbocharger, variable turbo geometry and GPA (general purpose actuator). The main part of this bachelor thesis deals with the preparation of the springs, which was designed according to the requirements of the customer. The required power load was measured and found during normal use of the car.
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