Differentiation of black gel inks using optical and chemical techniques

Gel ink pens have become a common writing instrument in the United States. Questioned document examiners often attempt to optically differentiate gel inks from each other and from other non-ballpoint ink writings (e.g., those from roller-ball pens). Since early formulations were primarily pigment-based, they do not elute when analyzed by thin-layer chromatography. However, recent gel ink formulations (i.e., within the past five years) include dye-based inks that can be easily separated. This study differentiates black gel inks using optical and chemical techniques. The techniques include: microscopy, visible and near infrared reflectance, near infrared luminescence, thin-layer chromatography (TLC), spot tests, and gas chromatography/mass spectrometry (GC/MS). As a result of this study a flow chart has been developed allowing for a systematic determination of a questioned ink. In addition, an analysis of volatile compounds found in gel inks revealed that there are some unique ingredients that may be found in gel inks that are not typically found in other non-ballpoint inks.     

A selection of some of Dr. McCrone's high and low profile cases in the forensic analysis of art

Throughout Dr. McCrone's active professional career of over 60 years, he worked on many cases involving the forensic analysis of art. This is an overview of a small portion of these cases. Included (exposed as fakes) are the Shroud of Turin, the Vinland Map, Mayan pottery illustrations and Larionov pastels. Also included, with strong support for authentication, are three paintings attributed to Manet, Giorgione, and Leonardo da Vinci.     

Expert evaluation of the gunshot distance based on the volume of wound canal in flat bones

Different-distance experimental shots were made from a rifled gun at flat bones. Those shot distances were established, at which the wound canal had the smallest volume, and, at which entry and exit holes were virtually identical and matched the bullet diameter. A bigger shot distance was associated with an increasing volume of the wound canal caused by a bigger exit hole. A smaller shot distance led, also, to an increasing volume of the wound canal caused by bigger entry and exit holes. The volume of the wound canal in flat bones can be used as a reliable criterion in assessing the shot distance.     

The morphological specificity of relaxation of cardiomyocytes and their value in forensic medical diagnostics

The morphological specificity of different conditions of cardiomyocytes was studied in myocardia of 50 cadavers of men who died of a variety of reasons. All conditions, except for the normal relaxation of cardipmyocytes, were found to result from damages in the contractive apparatus. Morphological variations of relaxation of cardiomyocytes are described.     

Significance of changes in the myocardium for the forensic-medical diagnosis of death as a result of alcoholic cardiomyopathy

Significance, of the weight and dimensions of heart as well as of fat dystrophy of cardiomyocytes and of the related detection methods is demonstrated for the diagnosis of alcoholic cardiomyopathy (ACMP). When such patients die in a state of alcoholic intoxication, the diagnosis should be death of acute alcoholic intoxication. Lethality of ACMP can be diagnosed only in those who die in the sober condition or with an insignificant level of alcohol.     

Significance of tooth anomalies in personal identification

Described in the paper are the study results of the stomatological status of 385 cadavers, in whom the frequency rate of anomalies of separate teeth and of their varieties were evaluated as applicable to the personality identification tasks.     

A definition of the nomenclature of allele variants and a description of allele polymorphism within a molecular-genetic individualization system based on the pentanucleotide tandem replication of HUMCD4

While analyzing the available published data, we found significant differences in definition of alleles of the HUMCD4 polymorphic chromosome locus. It is an obstacle for comparing the expertise results obtained while using the locus as molecular individualization system in different laboratories and, as a consequence, it hinders the use of the said marker in building up a reference database. The structure of the HUMCD4 locus was analytically investigated and the distribution of the locus alleles was systemized in a sample of 407 persons (citizens of Russia who are not blood relatives) within the present case study for the purpose of a detailed definition of its allele's characteristics. We worked out recommendations related with the nomenclature standardization of alleles of the HIMCD4 locus and specified the main population features of the locus polymorphism on the bases of the studied sample of Russia's citizens. The results can be used as reference parameters in interpreting the findings of the molecular-genetic identification expertise and examinations and in building up databases.