A rapid gas chromatographic method for the fingerprinting of illicit cocaine samples.

A gas chromatographic (GC) fingerprint method, based on the presence or absence of six congeners, was developed for illicit cocaine samples. The fingerprint utilizes the relative abundances of these congeners towards each other, disregarding cocaine as the main constituent, and can be expressed numerically or graphically in the form of pictograms for rapid visual comparison. The method can be applied directly to a solution of the sample in chloroform, without previous workup procedures. More than 70 unrelated samples were analyzed and a great variation was observed in the parameter composition. On the other hand, a remarkable similarity could be seen between related samples. The GC fingerprint method may be considered an important contribution for sample comparison, as is exemplified by a subdivision of the analyzed samples in different categories, based on the number and types of congeners found.     

Polymerase chain reaction (PCR) amplification and human leukocyte antigen (HLA)-DQ alpha oligonucleotide typing on biological evidence samples: casework experience.

The polymerase chain reaction (PCR) method of specific gene amplification was used in casework to synthesize millions of copies of the polymorphic second exon of the human leukocyte antigen (HLA)-DQ alpha (or DQA1) locus from a variety of evidence samples. The HLA-DQ alpha allelic variants in the amplified deoxyribonucleic acid (DNA) were determined in a rapid non-radioactive test by hybridization to sequence-specific oligonucleotide probes in both the dot-blot and reverse dot-blot formats. This genetic typing system has been subjected to blind proficiency testing; the performance of this test in the analysis of experimentally mixed samples was also evaluated. As of August 1990, over 250 cases have been tested and more than 2000 individual evidence (bloodstains, semen stains, individual hairs, bone fragments, and tissue sections) and reference samples have been analyzed. The first 198 of these cases are summarized in this paper; in 65% of the cases with conclusive results a suspect was included, and in 35%, all suspects were excluded. Individual cases as well as some of the general issues relating to forensic science analysis and this genetic typing system are discussed. The high rate of exclusion reported here combined with the ability of PCR to type old evidence samples suggests the relevance of this genetic test for postconviction review; two cases in which the convicted suspect was excluded are discussed.     

Finding audiences, changing beliefs: the structure of research use in Canadian health policy

The impact of research information depends on its ability to change beliefs or policy assumptions within the relevant audiences. As a hybrid of American and British systems, Canada's chosen decision-making structure for policy-making and its legislative framework for health insurance make these audiences unclear and not readily accessible. This factor and historical characteristics of the research community which made them only partially responsive to the values of decisionmakers provide an explanation for the limited past use of research information in Canadian health policy. More recently, improved responsiveness by researchers and an emerging definition of the audiences by legislative policymakers are bringing about a gradual increase in the potential impact of research at the levels of administrative and clinical policy. Because of continuing decision-making constraints on legislative policy, however, impact at this level is predicted to remain diffuse, with only cautious acceptance of the changes in beliefs implied by research.     

Chinese democracy: The lessons of failure

China's experiments with democracy in this century were few in number, short in duration, and limited in their democratic characteristics. Democratic institutions malfunctioned in numerous ways. Nine sets of causes for the failure of Chinese democracy can be suggested: ideology, internal and external war, military intervention, Chinese political culture, underdevelopment, a peasant mass, flaws in the design of Chinese constitutions, moral failures by democratic politicians, or the lack of transactional benefits for military‐based elites in the process of democratic transition. Each of these factors is reviewed critically with an eye to its possible lessons.     

Sudden death in angiodysplasia of the gastroesophageal junction.

A 22-year-old Korean soldier, who had received blows to the neck and epigastrium from an officer 10 h earlier, suddenly died after massive hematemesis. He had been in relatively good health except for episodes of blood-tinged vomiting approximately 5 and 7 months prior to this event. Postmortem examination revealed angiodysplasia involving the gastroesophageal junction, and the stomach was distended with blood. No abnormal findings were present around the whole viscera, and the duodenum was free of blood. The pathologic significance of upper gastrointestinal angiodysplasia as a potential source of bleeding and a chronologic correlation between the trauma and bleeding are discussed.