Biomedical subjects
Publications and source records attributed to Mark Benecke.
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Wounds of living persons are a potential target for the same flies that live, or feed early on corpses. This can lead to complications in estimation of PMI but also allows to determine additional information that might be valuable in a trial, or during the investigations [e.g., M. Benecke, R. Lessig, Child neglect and forensic entomology, Forensic Sci. Int. 120 (2001) 155-159]. With forensic entomology, and forensic entomologists being more and more present, even lower profile cases like the neglect of elderly people (without violence being used against them; i.e., natural death) comes to our attention. Furthermore, much more people grow older than in the past years which leads to increased awareness of malpractice of caregivers in the professional, and personal environment [DPA (German Press Agency), Studie an 17000 Leichen: Jeder Siebte vor Tod falsch gepflegt (Every seventh elderly person not cared for sufficiently), German Press Agency dpa # 051402, Jan 3, Jan 5, 2003] . We briefly sketch three cases in which forensic entomology helped to better understand the circumstances of death, and the type and intensity of neglect before death.
The hypervariable tetranucleotide STR polymorphism DXS10011 is a powerful marker for forensic purposes. Investigation of this STR led to an allele nomenclature which is in consensus with the ISFG recommendations. DXS10011 is located at Xq28 and genetically closely linked to DXS7423 and DXS8377 but is unlinked to HPRTB and more distant X-chromosomal STRs. DXS10011 is a very complex marker exhibiting some structural variants within alleles of identical length. Two types of repeat structure (regular and inter-alleles) are known and described as types A and B. Two SNPs which are in strong linkage disequilibrium to the different sequence types were found in the repeat flanking region. The type A sequence consists of a long stretch of uninterrupted homogenous repeats which is highly susceptible to slippage mutation during male meiosis.
Forensic scientists may encounter blood spatter at a scene which may be pure or a mixture of fly artifacts and human bloodstains. It is important to be able to make an informed identification, or at least advanced documentation of such stains since the mechanics of production of fly artifacts are not determinable to the crime scene reconstructionist from regular police forces. We describe three cases in which experiments and crime scene reconstruction led to additional information. Case 1: Above the position of a victim, numerous blood stains of the low-high-velocity type were found. Exclusion of these stains being caused by force (but instead caused by the activity of adult blow flies) by use of the following observations that were confirmed in experiments: (a) sperm-/tadpole-like structure with length > width, (b) random directionality, and (c) mixture of round symmetrical and teardrop shaped stains. Case 2: A reddish spatter field was found on a fan chain two rooms away from the place where a dead woman was found. Localization of the spatter on the bottom end of the surface hinted strongly towards fly activity. Case 3: Double homicide; submillimeter stains were found on a lamp between the two corpses. Activity of flies was less likely compared to alternative scenario of moving lampshade and violent stabbing.
For several years Y-chromosomal microsatellites (short tandem repeats, STRs) have been well established in forensic practice. In this context, the genetic characteristics of the Y chromosome (i.e. its paternal inheritance and lack of recombination) render STRs particularly powerful. However, genetic differences between male populations appear to be larger for Y-STRs than for autosomal STRs, a fact that is most likely due to the higher sensitivity of Y-chromosomal lineages to genetic drift (Forensic Sci Int 118 (2001) 153). The assessment of probabilities for matches between haplotyped male persons or traces/persons requires the typing of a large number of haplotypes in the appropriate reference populations. The haplotype data of a large number of European as well as South and North American populations have been collected and are continuously published online (Y-STR Haplotype Reference Database--YHRD; http://www.ystr.org). The most recent multicentric effort has led to the establishment of an Asian YHRD (http://www.ystr.org/asia) which has been available since January 2002. All databases are maintained and curated at the Institute of Legal Medicine, Humboldt-University, Berlin and will soon be fused to a global repository including populations from all continents.
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The movie genre "snuff" appeared in the late 70s and shows the allegedly real, often cruel killing of people. More recently, a growing number of short video clips have been distributed via the internet, which also belong into this category and were clearly recognized as fictional on the basis of technical details by two study groups at the 80th Annual Meeting of the German Society of Legal Medicine held in Interlaken from 25 to 29 September 2001 (Schyma/Seidl). By means of a brief review of film history the article shows that "snuff movies" originated from a certain prevailing trend, examples of which are the murder of the actress Sharon Tate by the group around Charles Manson, the development of B horror movies, a promotional campaign for a film which flopped in 1971 (renamed several times by the distribution company from "American Cannibal" to "Snuff" to "Big Snuff") and elements of urban legends. Retrospectively there are no clues that Snuff films--i.e. movies openly distributed and actually available to the public, which were not private documentations found by the police at the homes of killers during investigations of homicides (such as in the murder series of the couple Bernardo/Homolka)--show real killings.
This is the first scientific report on the crimes of the homosexual paedophile sadist Luis Alfredo Garavito Cubillos, based on a research stay of the authors in Columbia, and including discussions with the investigators, and the offender. Between 1992 and 1999, Garavito killed more than 200 children in the core age span between 8 and 13 years (as an exception, 6 to 16 years). His modus operandi remained stable. During daytime, he lured children of a lower social status out of crowded parts of the city into hidden areas that were overgrown with high plants. Garavito promised either payment for easy work, or drugs, or made other socially believable offers. The children were tied up, tortured, raped, and killed by at least one cut in the lateral part of the neck, or by decapitation. During the killings, Garavito was drunk. Even after his arrest (for attempted sexual abuse under a wrong identity) it was not immediately possible to track his crimes since Garavito had frequently changed his places of stay and his jobs. He also grew different hairdos and used wrong names. During his still ongoing confessions, he directs the investigators correctly to all scenes of crime spread over large parts of Columbia. In our report, we give an overview over the course of investigations, hint to similarities in the cases of the German serial killer Denke (1920's) and homosexual paedophile serial killer Jürgen Bartsch (1960's), and give preliminary impressions on the offender's personality. Furthermore, the violent environment and juridical peculiarities in Columbia are discussed. In spite of a total penalty of 2600 years in prison, it is formally well possible that Garavito will be released out of prison within the next 10 to 20 years, i.e. even before the maximum sentence of 40 years will be over.
The forensic luminol test is used to screen large areas for the presence of blood. The heme-induced reduction of hydrogen peroxide is coupled to the oxidation of luminol resulting in luminescence. However, photographic documentation of the relatively weak and short-lived luminescence is difficult and luminol is now often replaced by other chemicals. In this study, we investigated reports from the Rostock police department that the addition of "Fit", a dishwashing detergent from former Eastern Germany, could both intensify and prolong the luminescence of luminol on blood stains. Even though this effect was reported only for the original composition of Fit but not the currently sold version, we found that both the old and the new version of Fit increase the brightness of the luminescence while decreasing its duration. This may be due to detergents in the dishwashing liquid, which permeabilize the plasma membrane of the erythrocytes, exposing the Fe3+ inside the cell and speeding up the entire reaction. We did not find any evidence of special ingredients in the old version of Fit that would cause both the increased brightness and prolonged duration of luminescence as reported by the Rostock PD.