DNA analysis of digested tomato seeds in stomach contents

Examination of stomach contents is one of the important steps in medical legal autopsy. Vegetative materials such as stems, roots, and seeds in stomach contents can be valuable evidence for providing investigative leads in death investigation. Currently, the identification of plant materials relies on microscopic and morphologic examination. We have found that many seeds are often protected from acid degradation during stomach digestion by their tough exterior seed coat. Tomato seeds were selected as a model system to assess DNA analysis and plant variety marker identification. The DNA-amplified fragment length polymorphism method was performed to determine if the DNA obtained from single seeds could be used for PCR analysis. From the amplified fragment length polymorphism results, some candidate markers for individualizing seeds from morphologically distinct tomatoes were identified. These data on DNA analysis of tomato seeds indicate amplified fragment length polymorphism is a viable procedure for the individualization of seeds from stomach contents in forensic investigations.     

Standardization of method for the analysis of dextromethorphan in urine

Dextromethorphan (DMP), an antitussive, is one of the most popular drugs among the younger generation in Korea. It usually is taken for its hallucinogenic properties and overdoses have been responsible for the fatalities that have been reported frequently. To control the abuse of DMP, the authorities restricted its use through classifying it as a controlled drug on October 2003. The purpose of this study is to provide a standard method for the analysis of DMP and its main metabolite, dextrorphan (DTP) in biological specimens. At first we established a standard operating procedure (SOP) for DMP/DTP in urine, and a method validation was performed. We also quantified DMP from 16 drug abuser's urine samples all of which were positive in the screening test for DMP. For the detection of DMP/DTP, urine samples were adjusted with 6N NaOH (pH 11) and extracted with ethylacetate. Thin layer chromatography was used as the screening test, and the final identification for DMP/DTP was used by GC/MS. The ions (m/z 271 for DMP, m/z 257 for DTP and m/z 86 for lidocaine as internal standard) were extracted from the full scan mass spectrum and were used for quantification. The selectivity, linearity of calibration, accuracy, within- and between day precision, limit of detection and quantification, recovery and stability were examined as parts of the method validation. Extracted calibration curves were linear from 100 to 2000 ng/mL for DMP and DTP with correlation coefficients better than 0.999. Limit detection was 50 ng/mL for DMP and DTP. Within-run precision (%CV) for DMP and DTP at three different concentrations (100, 500 and 1000 ng/mL) was 6.10-18.85%, and between-run precision was 1.70-7.86% for DMP and DTP. Absolute recovery for DMP and DTP was 57-74%, and relative recovery (extraction efficiency) was 80-89%. For 16 drug abuser's urine samples, the concentrations of DMP and DTP were 0.16-52.63 and 0.41-23.75 microg/mL, respectively. Method validation is an important requirement in the practice of chemical analysis, and it will be particularly useful in verifying the reliability of analytical results in the field of forensic science.     

Recidivism among spousal abusers: predictions and program evaluation

The relative effectiveness of two interventions for dealing with 200 court-referred spousal abusers is examined. The overall failure rate is 17.5%, with most recidivism occurring during the first 6 months after treatment. Offenders who completed a 14-week group treatment program called SAFE manifest significantly lower rates of recidivism (10.6%) than do offenders who did not complete the mandated treatment (38.8%). Some high-risk clients are referred to a cognitive restructuring treatment program called R&R, and those completing both programs (despite their high-risk status) have a recidivism rate of only 23.5%. Prediction of recidivism is difficult, with the LSI-R scores correctly predicting only 66% of the outcomes, using a cut score of 11.5. The exploration of other predictors is encouraged.     

Individuality of handwriting

Motivated by several rulings in United States courts concerning expert testimony in general, and handwriting testimony in particular, we undertook a study to objectively validate the hypothesis that handwriting is individual. Handwriting samples of 1,500 individuals, representative of the U.S. population with respect to gender, age, ethnic groups, etc., were obtained. Analyzing differences in handwriting was done by using computer algorithms for extracting features from scanned images of handwriting. Attributes characteristic of the handwriting were obtained, e.g., line separation, slant, character shapes, etc. These attributes, which are a subset of attributes used by forensic document examiners (FDEs), were used to quantitatively establish individuality by using machine learning approaches. Using global attributes of handwriting and very few characters in the writing, the ability to determine the writer with a high degree of confidence was established. The work is a step towards providing scientific support for admitting handwriting evidence in court. The mathematical approach and the resulting software also have the promise of aiding the FDE.     

Blind field test evaluation of Raman spectroscopy as a forensic tool

Analytical instrumentation for Raman spectroscopy has advanced rapidly in recent years to the point where commercial field-portable instruments are available. Raman analysis with portable instrumentation is a new capability that can provide emergency response teams with on-site evaluation of hazardous materials. Before Raman analysis is accepted and implemented in the field, realistic studies applied to unknown samples need to be performed to define the reliability of this technique. Studies described herein provide a rigorous blind field test that utilizes two instruments and two operators to analyze a matrix that consists of 58 unknown samples. Samples were searched against a custom hazardous materials reference library (Hazardous Material Response Unit (HMRU) Spectral Library Database). Experimental design included a number of intentionally difficult situations including binary solvent mixtures and a variety of compounds that yield medium-quality spectra that were not contained in the HMRU library. Results showed that over 97% of the samples were correctly identified with no occurrences of false positive identifications (compounds that were not in the library were never identified as library constituents). Statistical analysis indicated equivalent performance for both the operators and instruments. These results indicate a high level of performance that should extrapolate to actual field situations. Implementation of Raman techniques to emergency field situations should proceed with a corresponding level of confidence.     

Attitudes of people with disabilities toward physician-assisted suicide legislation: broadening the dialogue

This article presents the methods, findings, and implications of a participatory action research project that attempted to shed additional light on the debate over death with dignity (DWD) or physician-assisted suicide (PAS) legislation. In-depth, qualitative interviews with forty-five physically disabled residents of the San Francisco Bay Area, conducted by others with disabilities, revealed a wide breadth of opinions about and attitudes toward such legislation. For close to half of the participants, the desire for autonomy in making end-of-life decisions was a primary concern, yet fear that PAS legislation could violate this autonomy in various ways was a deep concern as well. Also reported were widespread accounts of disability-based discrimination and frequent expressions of fear about openly discussing positions that diverge from the official, publicly held opinions of disability leaders who oppose such legislation. The findings support those of a recent Harris poll demonstrating considerable diversity of opinion about PAS legislation among people with disabilities. The findings further suggest the need for additional research on the apparent disjunction between the diversity of attitudes held by those interviewed and the more unified position taken by many disability activists. Use of the study findings to promote greater dialogue within the community and to better position people with disabilities to take their place at the policy table also is discussed. In addition, the findings are seen as reinforcing the need for the public health community to become more engaged in this central ethical debate.