Inhibition of bleach-induced luminol chemiluminescence

The luminol chemiluminescence presumptive test for blood is based on the mild peroxidase activity of hemoglobin in basic peroxide solution. However, this test is subject to interference by strong oxidants, certain transition metal ions, and true peroxidases. This paper reports methods for reducing the interference caused by hypochlorite-containing bleaches. Amines such as 1,2-diaminoethane react rapidly with hypochlorite without interfering significantly with the hemoglobin-catalyzed oxidation. Thus, addition of 0.1 mol/L 1,2-diaminoethane to a standard luminol-peroxide spray lead to almost complete inhibition of hypochlorite-induced chemiluminescence while satisfactory chemiluminescence was still observed from bloodstains. If time allows, an alternative method for reducing interference from hypochlorite bleach is to wait several days until the bloodstains have dried thoroughly, by which time the hypochlorite will have decomposed.     

PCR-RFLP identification of Diptera (Calliphoridae,Muscidae and Sarcophagidae)--a generally applicable method

A simple, rapid method using restriction fragment length polymorphisms (RFLPs) within the internal transcribed spacer (ITS) regions of the ribosomal DNA gene repeat allows identification of insects and other organisms. We used the method to identify the morphologically similar Diptera larvae that are important in forensic entomology for estimating the time and location of death. Polymerase chain reaction (PCR) was used to amplify a region from the 18S to the 28S rRNA genes. The ITS1 and ITS2 regions provided variation between species and homogeneity within species, with the exception of Cochliomya macellaria. Combinations of the restriction enzymes DdeI, HinfI and Sau3AI provided diagnostic bands for identification of the ten species from three families of Diptera (Calliphoridae, Muscidae and Sarcophagidae).     

Daubert,Cognitive Malingering,and Test Accuracy

Daubert v. Merrell Dow Pharmaceuticals (1993) held that trial judges should permit expert scientific testimony only when the reasoning or methodology underlying the testimony is scientifically valid, and ... properly can be applied to the facts in issue. Vallabhajosula and van Gorp (V&vG, 2001) have suggested that when the Daubert standard is applied to tests for malingered cognitive deficits, courts should deem admissible only results that meet this mathematical standard: assuming a pretest probability of .3, a positive score on the malingering test should yield a posttest probability of at least .8. This paper shows that V&vG's criterion may lead to misunderstandings about the kind of information malingering measures provide. After reviewing cases that have discussed both the Daubert decision and malingered cognitive deficits, this paper uses data from the Test of Memory Malingering (T. N. Tombaugh, 1996) to provide a general characterization of the mathematical properties of malingering measures. The paper then describes how pretest knowledge about malingering is combined with knowledge about a test's performance to generate a posttest probability of malingering. The results can help mental health experts respond to Daubert-inspired challenges to conclusions based on malingering measures.     

Russian Authoritarian Pluralism: a Local and Global Trend?

Russia is a country that has witnessed increasingly authoritarian governance over the last decade. Civil liberties have been curtailed; local and regional political power has been usurped by the Kremlin. Russia remains a democracy insomuch as elections are conducted, but increasingly those elections are so heavily influenced by state control over the media and fiscal elements of social power that substantive Western notions of democracy have greatly atrophied. However, the decline in substantive democracy has received solid support from the Russian electorate. As such, under the leadership of Boris Yeltsin and Vladimir Putin, Russia has become an ‘authoritarian pluralist’ state that now expresses long-standing cultural affinity for a strong authoritarian rule under an increasingly thin veneer of democratic principles. Furthermore, variations of this new Russian model seem to be spreading globally.

Democracy is the dictatorship of the law. The stronger the state is, the freer the individual.

Vladimir Putin     

Analysis of artificial radiocarbon in different skeletal and dental tissue types to evaluate date of death

Radiocarbon dating, with special reference to the modern bomb-curve, can provide useful information to elucidate the date of death of skeletonized human remains. Interpretation can be enhanced with analysis of different types of tissues within a single skeleton because of the known variability of formation times and remodeling rates. Analysis of radiocarbon content of teeth, especially the enamel in tooth crowns, provides information about the date of formation in the childhood years and in consideration of the known timing of tooth formation can be used to estimate the birth date after 1950 ad. Radiocarbon analysis of modern cortical and trabecular bone samples from the same skeleton may allow proper placement on the pre-1963 or post-1963 sides of the bomb-curve as most trabecular bone generally undergoes more rapid remodeling than does most cortical bone. Pre-1963 bone formation would produce higher radiocarbon values for most trabecular bone than for most cortical bone. This relationship is reversed for formation after 1963. Radiocarbon analysis was conducted in this study on dental, cortical, and trabecular bone samples from two adult individuals of known birth (1925 and 1926) and death dates (1995 and 1959). As expected, the dental results correspond to prebomb-curve values reflecting conditions during the childhoods of the individuals. The radiocarbon content of most bone samples reflected the higher modern bomb-curve values. Within the bone sample analyses, the values of the trabecular bone were higher than those of cortical bone and supported the known placement on the pre-1963 side of the bomb-curve.     

The design and assessment of mock mass disasters for dental personnel

Mass disasters represent a significant challenge for dental personnel who are frequently called upon to provide identifications. Recently-published materials have highlighted the need to prepare such groups for the disaster challenge and to report inadequacies in existing preparation methods with an emphasis on team integration, organization, and the psychological and emotional effects of such work. Many studies have retrospectively reported errors that have been made in disaster situations, but few have addressed the issues proactively. In an effort to provide a prepared team of dental members, a mock disaster exercise (Operation: DENT-ID) is conducted annually in Vancouver, Canada. The present study analyzes the effectiveness of this exercise in relation to team organization, assessment of preparedness, and the emotional and psychological issues. An index of preparedness is developed and described. This index, in the form of a questionnaire, can be given to participants in mock disasters to assess the effectiveness of such exercises. While the focus of this paper is on the assessment of dental personnel, the indices and methods used can be applied to any group working within the disaster team. Results indicate that the increase in preparedness as a result of the exercise was highly significant.