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151.
PENDULUM--a guideline-based approach to the interpretation of STR mixtures   总被引:2,自引:0,他引:2  
Several years ago, a theory to interpret mixed DNA profiles was proposed that included a consideration of peak area using the method of least squares. This method of mixture interpretation has not been widely adopted because of the complexity of the associated calculations. Most reporting officers (RO) employ an experience and judgement based approach to the interpretation of mixed DNA profiles. Here we present an approach that has formalised the thinking behind this experience and judgement. This has been written into a computer program package called PENDULUM. The program uses a least squares method to estimate the pre-amplification mixture proportion for two potential contributors. It then calculates the heterozygous balance for all of the potential sets of genotypes. A list of "possible" genotypes is generated using a set of heuristic rules. External to the programme the candidate genotypes may then be used to formulate likelihood ratios (LR) that are based on alternative casework propositions. The system does not represent a black box approach; rather it has been integrated into the method currently used by the reporting officers at the Forensic Science Service (FSS). The time saved in automating routine calculations associated with mixtures analysis is significant. In addition, the computer program assists in unifying reporting processes, thereby improving the consistency of reporting.  相似文献   
152.
The use of a new technique, Fourier transform infrared (FTIR) chemical imaging, has been demonstrated for the enhancement of latent fingermarks on a number of surfaces. Images of untreated fingermarks on glass backgrounds with excellent ridge detail were acquired using infrared chemical imaging. High quality fingermarks on glass backgrounds were also developed using ethyl cyanoacrylate (super glue) fuming and subsequent infrared chemical imaging. This new method allows the collection of images from backgrounds that traditionally pose problems for current fingermark detection methods. The background may, for example, be highly colored, have a complex pattern, or possess other pattern or image characteristics that make it difficult to separate fingermark ridges using traditional optical or luminescent visualization. One background that has proven to be a challenging surface for the development of latent fingermarks is the Australian polymer banknote. To demonstrate the power and applicability of infrared chemical imaging, fingermarks fumed with ethyl cyanoacrylate were successfully imaged from Australian polymer banknotes.  相似文献   
153.
Suicide is second only to accidents as the most common cause of death for children and adolescents age 10 to 19 in Canada. All of the pediatric cases that were referred to the Hamilton Regional Forensic Pathology Unit from 1993 to 2002 were reviewed. For the purpose of this study, pediatric deaths were defined as deaths in the age group of 1 day up to and including 19 years of age. Specific criteria for suicide were applied to each case, independent of the manner of death issued by the coroner. The criteria were 3-fold. First, homicide had to be ruled out by the police investigation and autopsy findings. Second, the method had to be consistent with self-infliction. Finally, there had to be some evidence of suicidal intent. Questionable cases were discussed among the authors, and if reasonable intent could not be established, then the case was excluded. The autopsy and police reports were examined in detail regarding age, sex, location and method of suicide, presence of suicide notes, and any contributing psychologic factors or stressors. Of the 501 pediatric autopsies performed during the 10-year period, 31 (6%) met the criteria of suicide. The majority of cases (87%) were in older adolescents (age 15 to 19), and the male to female ratio was 2.4:1. Psychologic factors were identified in some of the cases, including depressed mood (77%), suicidal ideation (45%), previous suicide attempts (23%), and drug or alcohol problems (19%). Most of the suicides (61%) occurred in the victim's home, and 12 (39%) cases left a suicide note. In 9 cases (29%), alcohol or street drugs were detected postmortem, though in 8 cases toxicology was not performed. Hanging (48%) was the most common method of suicide, followed by firearms (13%), poisoning (10%), drowning (10%), and blunt force vehicular trauma (10%). Almost 60% of the male suicides were by hanging. No specific trend was identified in the 9 female suicides. These results were compared with similar studies within Canada and other countries. Overall, the method of suicide is dictated by what is convenient and readily available, though the acceptance of various suicide methods can change over time. Suicide prevention efforts should be tailored to address local trends.  相似文献   
154.
Forensic analysis of glass samples was performed in different laboratories within the NITE-CRIME (Natural Isotopes and Trace Elements in Criminalistics and Environmental Forensics) European Network, using a variety of Laser Ablation Inductively Coupled Plasma Mass Spectrometry (LA-ICP-MS) systems. The main objective of the interlaboratory tests was to cross-validate the different combinations of laser ablation systems with different ICP-MS instruments. A first study using widely available samples, such as the NIST SRM 610 and NIST SRM 612 reference glasses, led to deviations in the determined concentrations for trace elements amongst the laboratories up to 60%. Extensive discussion among the laboratories and the production of new glass reference standards (FGS 1 and FGS 2) established an improved analytical protocol, which was tested on a well-characterized float glass sample (FG 10-1 from the BKA Wiesbaden collection). Subsequently, interlaboratory tests produced improved results for nearly all elements with a deviation of < 10%, demonstrating that LA-ICP-MS can deliver absolute quantitative measurements on major, minor and trace elements in float glass samples for forensic and other purposes.  相似文献   
155.
Infectious microorganisms are important to multiple communities engaged in biodefense and biosecurity, including the agencies responsible for health, defense, law enforcement, agriculture, and drug and food safety. Many agencies have created lists of high priority infectious microorganisms to prioritize research efforts or to formally control the possession and distribution of specific organisms or toxins. However, the biological classification of infectious microorganisms is often complex and ambiguous, leading to uncertainty and confusion for scientists involved in biosecurity work. To address this problem, we created a database, known as the Microbial Rosetta Stone, which resolves many of these ambiguities and includes links to additional information on the microbes, such as gene sequence data and scientific literature. Here we discuss the efforts to coordinate organism names from pathogen lists from various governmental agencies according to biological relatedness and show the overlap of high-priority organisms from multiple agencies. To our knowledge, this is the first comprehensive coordination of pathogens, synonyms, and correct taxonomic names. The organized tables and visual aids are freely available at http://www.microbialrosettastone.com. This website provides a single location where access to information on a broad range of disease-causing organisms and toxins is available to members of the biosecurity community.  相似文献   
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158.
This is the latest edition of Baker & McKenzie's column on developments in EU law relating to IP, IT and telecommunications. This article summarises recent developments that are considered important for practitioners, students and academics in a wide range of information technology, e-commerce, telecommunications and intellectual property areas. It cannot be exhaustive but intends to address the important points. This is a hard copy reference guide, but links to outside web sites are included where possible. No responsibility is assumed for the accuracy of information contained in these links.  相似文献   
159.
The growth of mass media has complicated the relatioship between the courts and the media. Free press and fair trial rights are kept in balance by the use of judicial restraints and remedies such asvoir dire, change of venue, and gag orders. This balance has shifted back and forth during the past two decades. Current case law and legal codes are inconsistent and provide insufficient guidance to judges in their use of restraints and remedies. Nor is there a body of empirical research on the impact of news coverage and juror behavior capable of informing the courts at this time. In this paper, we review and critically assess the empirical social science literature as it pertains to the legal issues involving free press and fair trial. We argue that carefully conducted empirical research could provide important information to the courts. We suggest research directions and methodological caveats to increase legal relevance and scientific validity.  相似文献   
160.
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