STR analysis of artificially degraded DNA-results of a collaborative European exercise

Degradation of human DNA extracted from forensic stains is, in most cases, the result of a natural process due to the exposure of the stain samples to the environment. Experiences with degraded DNA from casework samples show that every sample may exhibit different properties in this respect, and that it is difficult to systematically assess the performance of routinely used typing systems for the analysis of degraded DNA samples. Using a batch of artificially degraded DNA with an average fragment size of approx. 200 bp a collaborative exercise was carried out among 38 forensic laboratories from 17 European countries. The results were assessed according to correct allele detection, peak height and balance as well as the occurrence of artefacts. A number of common problems were identified based on these results such as strong peak imbalance in heterozygous genotypes for the larger short tandem repeat (STR) fragments after increased PCR cycle numbers, artefact signals and allelic drop-out. Based on the observations, strategies are discussed to overcome these problems. The strategies include careful balancing of the amount of template DNA and the PCR cycle numbers, the reaction volume and the amount of Taq polymerase. Furthermore, a careful evaluation of the results of the fragment analysis and of automated allele calling is necessary to identify the correct alleles and avoid artefacts.     

Death by chainsaw: fatal kickback injuries to the neck

Each year over 3 million new chainsaws are sold in the United States. The operation of these newer saws combined with the millions of older chainsaws in circulation results in over 28,000 chainsaw-related injures annually. The majority of the injuries involve the hands and lower extremities with less than 10% involving injuries to the head and neck regions. Deaths while operating a chainsaw are extremely rare. The most common hazards associated with chainsaws are injuries caused by kickback, pushback, and pull-in. Kickback is the most common and poses the greatest hazard. Kickback occurs when the rotating chain is stopped suddenly by contact with a more solid area throwing the saw rapidly backward toward the operator. The cause of most injuries can be traced to improper use of the saw or poor judgment on part of the operator. We present two fatal chainsaw deaths; one with an older style saw, and the other with a modern type. In both cases the victims died from fatal injuries received to the neck region from a chainsaw kickback. The first case involved a 49-year-old white male operating an older style chainsaw with limited safety features. The second case involved a 38-year old white male who was operating a newer model chainsaw equipped with a low kickback chain in an unsafe manner.     

Cardiac concussion: definition, differential diagnosis, and cases presentation and the legal ramification of a misdiagnosis

A cardiac concussion is caused by a sudden, nonpenetrating, localized impact to the chest that is theorized to result in almost simultaneous sudden death from a disruption to the conductive system. The detailed external/internal forensic examination of the body reveals no evidence of structural, pathologic, or histologic signs of trauma to the heart. A cardiac concussion is a rare and often overlooked cause of sudden death. This type of sudden death is typically seen among younger individuals participating in sports involving projectiles and, to a lesser degree, where collisions occur. Cardiac concussions are clinically, pathologically, and chemically different from a cardiac contusion. The objective of this paper will be to define cardiac concussion, differentiate between cardiac concussion and cardiac contusion, and describe the clinical and pathologic features of a 32-year-old white male who died of a cardiac concussion following a collision with a catcher during a softball game. The civil ramification of incorrectly diagnosing the manner of death in cases of death involving a cardiac concussion will also be addressed.     

About the Authors

Biography

About the Authors     

Analysis and classification of common vegetable oils

The analysis of fatty acids from common vegetable oils was investigated for application to forensic casework. A base-catalyzed transesterification of the fatty acids to fatty acid methyl esters using tetramethylammonium hydroxide was simple, rapid, straightforward and inexpensive. Canola, corn, olive, peanut, safflower, soybean and sunflower oils were able to be classified based on their fatty acid methyl ester profiles. Using gas chromatography-mass spectrometry, the detection limits for canola, corn, olive, peanut and safflower oils were determined to be 0.4 mg/mL or less and 0.2 mg/mL or less for soybean and sunflower oils.     

Drawings of the opposite sex: Continued use of the draw a person test and young state hospital patients

The Draw A Person test has continued to be one of the most frequently utilized psychological tests with children and adolescents. This is especially true for the child/adolescent populations in state hospitals. Because of the frequent criticism leveled against the DAP's validity, this study was undertaken in order to provide normative data for the DAP with this particular clinical population. Previous research has focused on the drawings of the same sex as the subjects; this study deals with the characteristics of the drawings of the opposite sex. The subjects were 84 male and 66 female psychiatric patients from the Adolescent Unit (AU) at Rusk State Hospital. As each patient was admitted to the AU, he was scheduled for psychological testing, with the DAP, the Revised Beta, and the MMPI being a part of this testing. The results of this study indicate that IQ ranking is the most significant factor affecting DAP test performance by male subjects. IQ ranking was not found to significantly influence the drawings by females. Neither MMPI test performance nor social background factors were shown to significantly affect DAP test performance. It is suggested that in order for the DAP to become a more objectively utilized personality technique, a scoring method should be developed that takes into account the overall quality of the drawing in conjunction with the individual details of each area of the figure drawn. More focus should also be given to the characteristics of the opposite-sex figure drawn by the subjects and its potential interpretation.Received his M.S. degree in psychology from North Texas State University in 1968. Current interests include establishment of residential psychiatric facilties for children and adolescents, development of new treatment modalities for children and adolescents (i.e., Wilderness Camping Programs for emotionally disturbed children and adolescents), and understanding and developing working knowledge of the criminally insane child or adolescent.Received his Ph.D. in experimental psychology from the University of Alabama. His research interests include program evaluation and psychometric studies of psychological tests.Received his B.A. degree in mathematics at the University of South Florida in 1968 and his M.S. degree in statistics from Virginia Polytechnic Institute in 1970. His current interest is mental health statistics.Received his Ph.D. from Texas Tech University in 1975. His current interest is in assertion training.     

Not All are Aboard: Decolonizing Exodus in Joon-ho Bong’s Snowpiercer

This article interprets Joon-ho Bong’s Snowpiercer (2013) as a political allegory. First, we compare Bong’s film to Danny Boyle’s Sunshine (2007) and Christopher Nolan’s Interstellar (2014), two contemporaneous films about ecological crises. We argue that Snowpiercer exposes the limits of technocratic environmentalisms that obscure the links between ecological degradation, capitalist development, and colonial domination. Second, we put Bong’s film into conversation with autonomist Marxist and postcolonial accounts of social domination and transformation. We argue that Snowpiercer is about whether or not contemporary political economy has rendered the emancipatory strategies of recent centuries obsolete. Framed this way, the film proposes that global order is still capitalist and colonialist, but that Left projects must surpass state socialism and anti-colonial nationalism. What we call Bong’s “decolonial exodus” is the demand for a real alternative to both the ideology that there is no alternative to the existing order and the pseudo-alternative of authoritarian populism.