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971.
The recent formation of a United Kingdom and Irish working group, the Body Fluids Forum (BFF), highlighted the need to investigate different working practices prior to any inter-laboratory comparison work and identification of best practice. Various dilutions of semen were seeded onto swabs and cloth samples for each BFF member laboratory to test using their standard techniques. The results showed that the detection of acid phosphatase on swabs is best achieved using direct testing rather than on an extract from the swab. Extraction methods for spermatozoa require a balance to be achieved between using a sufficient volume of water to ensure optimal release and minimal volume to ensure a concentrated extract. PSA tests were investigated and found to be more sensitive than Choline. DNA profiles were obtained from samples in which no spermatozoa had been detected during microscopic examination.  相似文献   
972.
973.
The testing of oral fluid for drugs of abuse has increased significantly over recent years and is now commonplace in drug rehabilitation clinics, the workplace, prisons and custody suites. The global problem of identifying drugged drivers has also led to an increase in oral fluid testing at the roadside. The main requirements for the implementation of roadside drug testing are a rapid sample collection time, collection of a known sample volume and recovery of drugs from the collection device. We report here the development of the Cozart® DDS oral fluid collector, an oral fluid collector that combines rapid and adequate sample collection with satisfactory drug recovery. Oral fluid was collected from drug users (n = 134) and drug-free individuals (n = 137), using the Cozart® DDS oral fluid collector. The mean time for the completion of collection (full coloration of the sample presence indicator) was 34 s for drug-free individuals and 44 s for drug users. The average volume collected was 0.34 mL (n = 271). No chemical stimulant (to induce salivation) was used to achieve the collection times observed in either the drug-free or the drug-taking sample populations. Drugs were extracted from the collector using the Cozart® DDS buffer and drug recovery was determined by Cozart® enzyme immunoassays. The recovery studies showed that for amphetamine, Δ9THC, cocaine, methadone, methamphetamine, morphine and temazepam over 90% of the drug in the sample was eluted from the collector. The Cozart® DDS oral fluid collector provides a reliable mechanism for the collection of oral fluid at the roadside that achieves the rapid collection times required.  相似文献   
974.
Bites of Trombiculid mites implicated a suspect during a homicide investigation. Clinical documentation of the bites, correlation with entomological studies, and submission of evidence at trial are reported. Insects that have a discrete geographic distribution and leave bites of a characteristic nature may have important forensic science implications.  相似文献   
975.
The limited literature on the topic speculates that the rate of ADHD would be higher among incarcerated youth than found in the general population. However, to our knowledge no such published figures exist for juveniles in the United States. This study investigates the likelihood of ADHD diagnosis among 453 incarcerated youth and compares and contrasts a variety of demographic, social, educational, psychological, and criminal characteristics to the general literature on ADHD. Both similarities and differences are reported. This project was supported by Grant #99-RT-VX-K020 awarded by the National Institute of Justice. Points of view in this document are those of the author and do not necessarily represent the official position or policies of the U.S. Department of Justice. An early version of the paper was presented at the annual meeting of the Academy of Criminal Justice Science in Chicago, Illinois.  相似文献   
976.
After its victory in World War II, it was clear that United States should move beyond the disastrous policies of the 1930s, but it was less clear how. Ultimately, a lasting postwar strategy was forged under President Truman. Appreciating how Truman moved well beyond Roosevelt's guiding assumptions is essential to understanding the evolution of American grand strategy. One sees that wartime planning and grand strategy formulation can prove quite inadequate for dealing with postwar challenges. An administration cannot be locked into assumptions, but must constantly test them. Thus, the Truman administration eventually developed and adopted containment and moved far beyond FDR's approach. More substantively, the fundamental geopolitical lesson of World War II and the early Cold War was that the United States must assume the essential balancing role relative to other major powers.  相似文献   
977.
978.
979.
A decade of spectacular progress in functional magnetic resonance imaging (fMRI) technology and systems neuroscience research has so far yielded few changes in our daily lives. The dearth of clinical applications of this prolific and academically promising research tool began raising the eyebrows of the public and the research funding agencies. This may be one of the reasons for the enthusiasm and interest paid to the growing body of literature suggesting that blood oxygenation level‐dependent (BOLD) fMRI of the brain could be sensitive to the differences between lie and truth. The word ‘differences’ is critical here since it refers to the often‐ignored core concept of BOLD fMRI: it is only sensitive to differences between two brain states. Thus, available studies report using fMRI to discriminate between lie and truth or some other comparative state rather than to positively identify deception. This nuance is an example of the extent to which applied neuroscience research does not lend itself to the type of over‐simplification that has plagued the interpretation of fMRI‐based lie detection by the popular press and the increasingly vocal academic critics. As an early contributor to the modest stream of data on fMRI‐based lie detection, I was asked by Dr Aldert Vrij to write a piece in favour of fMRI‐based lie detection, to be contrasted with a piece by Dr Sean Spence presenting an opposite point of view ( Spence, 2008 ). This seemingly straightforward task presented two hurdles: having to respond to the popular as well as scientific view of what lie detection with fMRI is and present a wholly positive view of evolving experimental data.  相似文献   
980.
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