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Stalking ve světě elektronických médií / Stalking in the world of electronic mediaSmolík, Viktor January 2012 (has links)
Stalking is extremely complicated phenomenon, which exists in our society. Despite the fact it's the subject of psychology studies for a long time, the knowledge about this phenomenon has spread to the public in the last few decades. This circulation was supported by the growth of electronic media, because in connection with this penetration it becomes easier a faster than before and stalkers gained new instruments to their hands. Victims were becoming constantly more vulnerable and society became fully conscious of the need of criminalization of this phenomenon. Stalking is a multidisciplinary phenomenon, which pervades many branches of research. Despite the knowledge about this phenomenon in public, information science and information management deal with stalking minimally. Therefore this thesis analyses stalking as a multidisciplinary phenomenon from the view not only informatics, but also from the view of other sciences. This thesis points to individual aspects of attacks through electronic media, to simplicity of their use and to the methods of defence against them. It points to the need of protection of personal data not only in a private life, but also in a professional life.
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Uneasy bodies femininity and death : representing the female corpse in fashion photography and selected contemporary artworksVan Rensburg, Thelma January 2016 (has links)
This mini-dissertation serves as a framework for my own creative practice. In this
research paper my intention is to explore, within a feminist reading, representations of
the female corpse in fashion photography and art. The cultural theorist Stuart Hall's
theories on the concept of representation are utilised to critically analyse and
interogate selected images from fashion magazines, which depicts the female corpse
in an idealised way. Such idealisation manifests in Western culture, in fashion
magazines, as expressed in depictions of the attractive/ seductive/fine-looking female
corpse. Fashion photographs that fit this description are critically contrasted and
challenged to selected artworks by Penny Siopis and Marlene Dumas, alongside my
own work, to explore how the female corpse can be represented, as strategy to
undermine the aesthetic and cultural objectification of the female body. Here the
study also explores the selected artists' utilisation of the abject and the grotesque in
relation to their use of artistic mediums and modes of production as an attempt to
create ambiguous and conflicting combinations of attraction and repulsion (the
sublime aesthetic of delightful horror), thereby confronting the viewer with the notion
of the objectification of the decease[d] feminine body as object to-be-looked-at. This
necessitated the inclusion of seminal theories developed by the French theorist, Julia
Kristeva (1982) on the abject and the Russian theorist, Mikhail Bakhtin (1968) on the
grotesque. / Dissertation (MA)--University of Pretoria, 2016. / Visual Arts / MA / Unrestricted
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Effectiveness of various cleaning agents at removing detectable traces of bloodGomez Marquez, Juan Gabriel 21 February 2021 (has links)
Forensic investigation television shows such as police procedurals, rooted in both fact and fiction, have become an ever-popular staple of modern television in the last 20 years. The popularity of these shows has been blamed for generating higher expectations for forensic evidence by juries across America and may also have had the effect of inspiring criminals attempt to cover up their crimes by destroying potential evidence, particularly bloodstains.
Luminol is a popular blood detection technique because it can be sprayed throughout an area in a dark room and will chemiluminesce when it interacts with hemoglobin. This chemiluminescence is a signal to investigators that latent blood may be located in that spot. Luminol’s specificity and sensitivity have long been studied. Luminol is a stable molecule that becomes oxidized when it comes in contact with an oxidant such as hydrogen peroxide and a catalyst. In this excited state, the molecule is unstable and forms 3-aminophthalate. This molecule produces light, and the luminescence slowly dies out as the molecule returns to its ground state.
Chemicals that disrupt the luminol reaction can be considered interferents. These include cleaning agents, biological agents, foods, and drinks, among others. Compounds such as sodium hypochlorite, sodium percarbonate, and hydrogen peroxide are commonly
used as primary cleaning products or as components in popular brands of household cleaners. Such multisurface cleaners, extra strength detergents or other chemicals are readily accessible to someone attempting to clean up a crime scene. Sodium hypochlorite, also known as bleach, has previously been found to cross react with luminol, generating a chemiluminescent reaction whether heme is present or not. Sodium percarbonate is also known as active oxygen and is used in detergents to improve their stain removing capabilities. It can affect the luminol and Bluestar® Forensic tests by causing a negative result, even in the presence of blood. Hydrogen peroxide is a common disinfectant and a necessary component of most presumptive blood tests, however, bulk quantities of it in the luminol reaction stop the reaction from proceeding. Antioxidants, found in many foods and drinks, can inhibit luminescence by preventing heme from being degraded, an important step in order for the luminol reaction to proceed.
The purpose of this investigation is to evaluate the effectiveness of common cleaning agents for removing detectable traces of blood based on published studies. Additionally, an attempt was made to determine if cleaning agents completely remove blood or if they disrupt the luminol reaction when a negative luminol result is obtained. To supplement the literature, a limited experiment was carried out and preliminary data was obtained. This investigation finds that some cleaners interfere with the luminol reaction by altering one or more components in a way that prevents the reaction from fully proceeding, even when blood is still present.
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Mineral absorption by submerged bone in marine environments as a potential PMSI indicatorMammano, Kristina Lynn 24 February 2021 (has links)
Human remains enter marine environments in a number of ways ranging from homicides, suicides, accidental drownings, shipwrecks, to burials at sea. Once the remains are discovered, a legal and forensic investigation begins. A key component to this investigation is the postmortem submergence interval (PMSI). Determining this range on skeletonized remains is a complicated process in which there is no accurate test; although barnacle growth data was previously used to determine PMSI, there are still limitations with that method. Therefore, a more reliable component of bone needs to be used as a potential PMSI indicator, such as its elemental composition.
Diagenesis starts affecting bones immediately and continues for thousands of years. Although diagenesis is a slow process, an exchange of elements between bone and the marine environment continually occurs. The purpose of the present study is to determine whether an increase in marine elements is found within the composition of bone after being submerged in a marine environment for up to 20 months. The present study will also determine whether bones submerged in different aquatic environments have significantly different elemental concentrations.
For the time trials, pig femora were submerged in lobster cages off the coast of the University of Massachusetts Boston for 2-20 months. For the salinity trials, pig femora were submerged in a freshwater pond (Holliston, MA), the Inner Boston Harbor, and an ocean inlet near Woods Hole, MA for 18 months. All bone samples were dried, milled, homogenized, and analyzed by ED-XRF under He purge. The initially produced mass percentages of the identified elements were corrected with certified values of standard reference materials (NIST 1486, 1646a, and 2702). A Pearson’s correlation test determined that the concentrations for K, Fe, Zn, Sr, Si, S, Cr, Mn, Cl, Br, Ta, and W were significantly correlated to the amount of time submerged in the water. An ANCOVA analysis was applied to the significant elements noted above. After adjusting for the amount of time submerged, the concentrations of K, Fe, Sr, Si, S, Cl, Br, and Ta were determined to be significantly different between the control samples (never submerged) and the submerged samples (submerged for 2-20 months). K was the only element that had greater concentrations in the control samples than the submerged samples, most likely because of the decrease in mass percent as other environmental elements were incorporated into the bone. S and W were significantly related to the number of months submerged, with S being positively influenced and W being negatively.
A multivariable linear regression was run in order to identify a means of predicting the amount of time submerged from the elemental concentrations of an unknown bone from a marine environment. The regression produced an equation that used the concentrations for K, Sr, Si, S, Cr, Cl, and Br to predict the PMSI in months.
For the salinity trials, a one-way ANOVA was performed on all the elemental concentrations from the different salinity environments. Post hoc tests determined significant differences in elemental concentrations for K, Fe, Si, S, Al, Ti, Cr, Ni, Mn, Cl and Br among the different submergence locations; elemental concentrations of S, Fe, Mn, Cl, K, and Br were either significantly different between the fresh, brackish, and saltwaters or the freshwater and some form of marine water (brackish and salt). The trends in the other elemental concentrations were less obvious due to the impact of pollution within the surrounding environments.
The linear regression equation created in the present study accounted for the majority of the variance in the outcome (R2 = 80.2%); however, this equation should not currently be applied in forensic investigations. The study needs to be repeated a number of times with other bone samples from the same and different submergence locations, in order to determine the accuracy and usefulness of the equation. Although not verified, this regression equation may be useful in analyzing samples from brackish and saltwater environments, because the majority of the variables within the equation (K, Sr, S, Cl, Br) were consistent among the fresh, brackish, and saltwater samples.
Time constraints, small sample sizes, and variance among samples were the major limitations of the present study. Even with limitations, significant results were produced by the ED-XRF analysis. Future research should expand upon the methodologies of XRF analyses of bones, especially those from marine environments. Because of their relevance to forensic investigations and PMSI, future research should include longer experimental periods, more salinity locations, more information on the surrounding water components, and more comparisons among instrumentation.
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Corrosion characteristics of seven metals in three aqueous environments for forensic applicationsTong, Tianqi 03 November 2015 (has links)
Corrosion characteristics of seven varieties of metals—zinc, brass C260, stainless steel 302, stainless steel 316, stainless steel 420, stainless steel 430, and stainless steel 440—in three aqueous media—Atlantic Ocean, Charles River, and deionized waters—were assessed via mass loss methods over 32 weeks, with supplemental data in the form of photomicrographic records. Concurrently, tests were conducted to determine the degree of measurement error resulting from the analytical scale used during corrosion assessment. This was accomplished by using reference samples of each type of metal and a glass vial as the container that held the metal and water samples. These error tests indicated that while the mass error associated with the metal samples was low, the error in mass associated with the vial displayed error margins two orders of magnitude larger than the error margins for the smaller metal samples. Further, control tests and statistical analysis indicated that this variation was the result of some quality inherent to the vial.
The metal samples involved in the corrosion assessment experiment generally displayed corrosion characteristics in agreement with trends reported in the literature. Zinc produced the greatest quantity of corrosion residues out of all the metals studied. Brass C260 also developed visible corrosion. For example, brass C260 developed dark green/brown adherent residue and whitish blue-tinted nonadherent residue in Atlantic Ocean water, faint greenish tarnishing and some dark green spots and dots over time in Charles River water, and only faint greenish tarnish in deionized water. In contrast with zinc and brass C260, the stainless steels did not exhibit signs of significant corrosion rates excepting stainless steel 420 (SS420), which displayed pitted features surrounded by multi-colored rings on all of its Atlantic Ocean immersion samples and 25% of its Charles River immersion samples. Atlantic Ocean water generally caused the greatest degree of corrosion for all metals, followed by Charles River water, then deionized water, except in the case of zinc.
Residues found on zinc samples immersed in the three different water types were similar to each other in coloration. SS420 samples immersed in different waters also displayed similar-colored residues. Comparisons between the corrosion features of SS420 and the single stainless steel 430 and 440 samples that did show visible corrosion in Atlantic Ocean water suggested that minor compositional variations between stainless steels have little effect on the visual characteristics of the corrosion residues they form.
Corrosion rates were calculated using linear regressions of the mass loss data for all metal sample sets. While some of these corrosion rates approached literature-reported values for the metal in question, the distributions of the mass loss data sets indicated that any mass changes that resulted from corrosion were likely too small for the electronic scale to detect. Consequently, it is recommended that future corrosion studies using the mass loss method utilize metal samples similar in size to objects typically found at crime scenes.
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Acquiring chemical attribute signatures for gasoline: differentiation of gasoline utilizing direct analysis in real time - mass spectrometry and chemometric analysisDavis, Ashley 03 November 2015 (has links)
Gasoline is a substance commonly encountered in forensic settings. Unfortunately, gasoline is an easily obtainable ignitable liquid that arsonists commonly use to initiate or expedite the spread of an intentionally set fire. Fires claim the lives of many people each year in addition to causing widespread property damage. Many fire scene investigations result in charges of arson, which has the legal connotation of a committed crime. For this reason, extensive analysis and investigation must be undertaken before any suspected arson scene is deemed an actual case of arson. Although ignitable liquids, including gasoline, may be present at the scene of a fire, it does not necessarily mean they were intentionally used as accelerants. An accelerant is a fuel used to initiate a fire. These realities, in addition to several other factors, demonstrate why a rapid, reliable, gasoline analysis method is crucial to forensic applications. In this thesis, direct analysis in real time – mass spectrometry (DART-MS) is evaluated as a potential method that could better identify, distinguish and classify gasoline brands from one another. Techniques such as DART-MS could enable forensic laboratories to better identify questioned gasoline samples.
Many ignitable liquids share similar chemical properties, and forensically relevant evidence is often obtained from a crime scene in less than favorable conditions. Fire debris can encompass various materials, including burnt carpet, flooring, items of furniture and clothing, among others. If gasoline was used as an accelerant, it may be present in trace amounts after the termination of the fire. Materials submitted for laboratory analysis may be substrates with compositions that have components similar to those found in some ignitable liquids. These are just a few of the potential obstacles that could be encountered with analyzing fire debris in a forensic setting. Traditionally, gas chromatography – mass spectrometry (GC-MS) methods are utilized for gasoline analysis in the criminal laboratory setting.
While traditional GC-MS methods are sensitive and able to classify samples as gasoline, they are time consuming in terms of both sample preparation and analysis. Additionally, they do not generate differential mass spectral data based on the brand of gasoline. Conversely, gasoline analysis in this research, utilizing the DART-MS method, demonstrated that five different brands of gasoline could be distinguished from one another both by visual examination of mass spectra and with methods of chemometric analysis. Advantageously, the DART-MS method, an ambient ionization technique, requires little sample preparation and a rapid sample analysis time, which could drastically increase the throughput of standard sample analysis with further method development. The goals and objectives of this research were to optimize the DART-MS parameters for gasoline analysis, determine if DART-MS analysis could distinguish gasoline by brand, develop chemometric models to appropriately classify gasoline samples, and finally lay groundwork for future studies that could further develop a more efficient and discriminating DART-MS gasoline analysis method for forensic casework.
Each brand of gasoline was observed to have a chemical attribute signature (CAS) consisting of not only low-mass ions, but also a variety of high-mass ions not usually observed with gasoline samples analyzed by GC-MS. Although variables including season, storage time, dilution and age of the gasoline were observed to contribute to the resulting mass spectral data, once the mass spectra are better understood, they could offer even more discriminating power between samples than simple analysis of the gasoline brand. In this research, DART-MS parameters were first optimized for gasoline analysis. Subsequently, the five acquired brands of gasoline: Shell, Sunoco, Irving, Cumberland Farms and Gulf, were analyzed both undiluted (or neat) and diluted utilizing the DART-MS analysis method. GC-MS data was generated and analyzed to show comparisons.
After analyzing the data generated by both approaches, it was apparent that the DART-MS method could generate CASs based on the gasoline brand and offer a degree of differentiation that traditional GC-MS does not.
Additional chemometric analyses utilizing principle component analysis (PCA) and the construction of models with Analyze IQ Lab software verified that the gasoline brands were distinguishable when samples were analyzed with this ambient ionization method. PCA plots of the neat gasoline demonstrated clustering based on brand. Additionally, models constructed from training samples generated from DART-MS analysis of the various brands were able to accurately classify gasoline samples as "yes" or "no" when a test set of gasoline was compared to all five brands. The lowest associated testing error rate for some of these models was 0%. However, additional analysis with greater sample sizes needs to be further carried out to more accurately evaluate this method of gasoline analysis and classification.
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Why Some Bodies Matter: Defacement and Narrative in Historical Forensic CasesDuncan, William N., Stojankowski, Christopher M. 05 March 2014 (has links)
Since the 1980s, ethnographers have increasingly explored the ways that dead bodies and body parts may have significant and dynamic afterlives by virtue of their psychological, social, political, and economic potential [...]
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A Fatal Drug Interaction Between Oxycodone and ClonazepamBurrows, David L., Hagardorn, Andrea N., Harlan, Gretel C., Wallen, Ellen D.B., Ferslew, Kenneth E. 01 January 2003 (has links)
A case is presented of a fatal drug interaction caused by ingestion of oxycodone (Oxycontin®) and clonazepam (Klonapin®). Oxycodone is an opium alkaloid used in long-term pain management therapy. Clonazepam is a benzodiazepine used for the treatment of seizures and panic disorders. The Drug Abuse Warning Network (DAWN) has reported an increase of 108% in the last two years of emergency department episodes related to Oxycontin®. Six billion prescriptions were written for Oxycontin® in the year 2000, an 18-fold increase from four years previous (1). Oxycontin has recently gained enormous notoriety at the local and national levels; however, there are very few previously documented cases of lethal drug interactions between oxycodone and clonazepam. Synergistic effects between these two drugs are postulated to arise from different agonistic mechanisms producing similar physiological changes. It is also theorized that clonazepam may inhibit the metabolism of oxycodone. A 38-year-old white female was found dead in Jefferson County, Tennessee in March of 2001. The deceased had physical evidence of previous drug abuse and positive serological findings of hepatitis B and C. Prescription pill bottles filled under the name of the deceased, as well as another name, were found with the body. Serum, urine and gastric contents from the deceased were screened for numerous drugs and metabolites using a combination of thin layer chromatography and immunoassay techniques (EMIT and FPIA). Analysis of biological specimens from the deceased revealed the presence of: benzodiazepines, opiates (oxycodone), and trazodone metabolites in the serum; cannabinoids, benzodiazepines, opiates (oxycodone), trazodone, trazodone metabolites, nicotine, and nicotine metabolite in the urine; and benzodiazepines, opiates (oxycodone), nicotine, and nicotine metabolite in the gastric contents. Quantitative analyses for clonazepam was performed by high performance liquid chromatography (HPLC) and revealed a plasma concentration of 1.41 μg/mL. Plasma oxycodone and urine 11-nor-carboxy-delta-9-tetrahydrocannabinol concentrations were determined by gas chromatography/mass spectrometry and revealed concentrations of 0.60 μg/mL and 27.9 ng/mL, respectively. The deceased had pathologies consistent with severe central nervous system (CNS) and respiratory depression produced by high concentrations of clonazepam and oxycodone including collapsed lungs, aspirated mucus, and heart failure. The pathologies were sufficient to cause death, which was officially attributed to a drug overdose; however, the manner of death was unknown.
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The Distribution of Sevoflurane in a Sevoflurane Induced DeathBurrows, David L., Nicolaides, Andrea, Stephens, Gretel C., Ferslew, Kenneth E. 01 January 2004 (has links)
The distribution of sevoflurane (fluoromethyl 2,2,2,-trifluoro-1-(trifluoromethyl) ethyl ether) in blood, urine, liver, kidney, vitreous humor, and tracheal aspirate is presented from a subject with a sevoflurane induced death. Sevoflurane is a nonflammable general anesthetic administered by inhalation of vaporized liquid. Although general inhalation anesthetics have the potential to be fatal if not properly administered, the incidence of abuse is minute in comparison to other illicit drugs (1). Currently, there are no citations in the literature defining the body distribution of sevoflurane in a sevoflurane induced death. The decedent was found lying in a bed with an oxygen mask containing a gauze pad secured to his face. Three empty bottles and one partially full bottle of Ultane™ (sevoflurane) were found with the body in addition to two pill boxes containing a variety of prescription and non-prescription drugs. Serum, urine and gastric contents from the deceased were screened for numerous drugs and metabolites using a combination of thin layer chromatographic, colorimetric and immunoassay techniques. Analysis of biological specimens from the deceased revealed the presence of: amphetamine, caffeine, pseudoephedrine, nicotine, nicotine metabolite, and valproic acid. Sevoflurane concentrations were determined by headspace gas chromatography with flame ionization detection and revealed concentrations of 26.2 μg/mL in the blood, 105 μg/mL in the urine, 31.9 μg/mL in the tracheal aspirate, 86.7 μg/mL in the vitreous humor, 30.8 mg/kg in the liver, and 12.8 mg/kg in the kidney. The decedent had pathologies consistent with respiratory suppression including pulmonary atelectasis, pulmonary edema, and neck vein distention. The official cause of death was respiratory suppression by sevoflurane and the manner of death was unclear.
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Analysis of heat-induced DNA damage during PCR and verification, validation and comparative analysis of two PCR megaplexesSaleem, Saman 03 November 2015 (has links)
Biological evidence collected at crime scenes are often subjected to forensic deoxyribonucleic acid (DNA) testing. During forensic DNA testing the DNA from the evidence and known samples are extracted, purified, amplified using Polymerase Chain Reaction (PCR), and analyzed using capillary electrophoresis (CE). In order to appropriately compare the profile of the suspect to the evidence, it is essential that interpretation parameters and optimized processing schemes are established. This study endeavors to accomplish this by: first, evaluating whether the PCR temperature cycling is detrimental to the amplification process; and second, by establishing and comparing interpretation parameters for two commonly employed short tandem repeat (STR) megaplexes.
To evaluate the effects of temperature cycling on downstream signal, a dynamic systems model was developed, validated, and used to test the effects of temperature on DNA damage and the subsequent fluorescence signal. Though DNA is generally thought to be a stable molecule, heat-induced damage does occur. Specifically, this model assesses the damage to the guanine and cytosine bases during temperature cycling. The model conducts the amplification of a single locus during PCR and generates the peak height observed after capillary electrophoresis. The model was designed to assess not only the effects of heat-induced DNA damage but to also incorporate variability in PCR efficiency. The simulated data indicate that heat-induced DNA damage does not significantly reduce the allelic signal. Also, although changes in PCR efficiency introduce variability in the peak heights at all targets, the peak heights observed with and without heat-induced DNA damage are not significantly different. In fact, the variation in PCR efficiency has a larger effect on the number of amplicons produced than does the heat-induced DNA damage.
The second part of this study compares two PCR amplification megaplexes, PowerPlex® Fusion and GlobalFiler®, by evaluating their sensitivities, limits of detection, presence of artifacts, heterozygous peak balance, and ability to amplify minor contributors in DNA mixtures. Analysis of single source samples using weighted least squares regression analysis indicates that PowerPlex® Fusion has greater analytical sensitivities and lower limits of detection at comparable dye channels, and both kits display similar heterozygous balance. However, the GlobalFiler® processing scheme produced fewer artifacts for the various single source samples analyzed, particularly at higher target amounts. Also, analysis of two and three person DNA mixtures indicates that both megaplexes perform equally well when detection of the minor contributor is the criterion.
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