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Although the microscopical comparison of human hairs has been accepted in courts of law for over a century, recent advances in DNA technology have called this type of forensic examination into question. In a number of cases, post-conviction DNA testing has exonerated defendants who were convicted in part on the results of microscopical hair comparisons. A federal judge has held a Daubert hearing on the microscopical comparison of human hairs and has concluded that this type of examination does not meet the criteria for admission of scientific evidence in federal courts. A review of the available scientific literature on microscopical hair comparisons (including studies conducted by the Royal Canadian Mounted Police and the Federal Bureau of Investigation) leads to three conclusions: (1) microscopical comparisons of human hairs can yield scientifically defensible conclusions that can contribute to criminal investigations and criminal prosecutions, (2) the reliability of microscopical hair comparisons is strongly affected by the training of the forensic hair examiner, (3) forensic hair examiners cannot offer estimates of the probability of a match of a questioned hair with a hair from a randomly selected person. In order for microscopical hair examinations to survive challenges under the U.S. Supreme Court's Daubert decision, hair microscopists must be better trained and undergo frequent proficiency testing. More research on the error rates of microscopical hair comparisons should be undertaken, and guidelines for the permissible interpretations of such comparisons should be established. Until these issues have been addressed and satisfactorily resolved, microscopical hair comparisons should be regarded by law enforcement agencies and courts of law as merely presumptive in nature, and all microscopical hair comparisons should be confirmed by nuclear DNA profiling or mitochondrial DNA sequencing.

A model based on a Michaelis-Menten nonlinear kinetic approach was used to analyze the kinetics of elimination of an intravenously infused lipid emulsion in the dog. The emulsion was administered at doses of 0.3, 3, or 6 g of lipid/kg of body weight. The model was applicable to all data regardless of the kinetic order of the elimination process operating. This can be either zero (linear), mixed, or first order (exponential). Furthermore, it was also found that parameters derived with the model can be used to predict the kinetics of elimination at different dosages. However, it was also shown that elimination parameters for a single bolus dose of lipid emulsion cannot be used to predict the manner in which a continuously infused dose will be eliminated.

Investigated whether variations in method of presentation of anxiety items (Es voice, E's taped voice, S's taped voice) will result in differences in autonomic arousal (as measured by self-report, galvanic skin responses, cardiac rate, blood pressure). Ss were 24 Naval Academy midshipmen. The procedure involved (1) training in deep muscle relaxation; and (2) measuring arousal after the presentation of anxiety-eliciting stimuli. Statistical analysis indicated that the influence of method of presentation was significant for galvanic skin response and self-reported anxiety. Comparison of cell means showed that verbal presentations were more effective in eliciting autonomic arousal than taped presentations. The results of this study provide partial evidence to support the conventional form of systematic desensitization as more effective than the newer automated or taped versions.

A study was performed comparing the elimination kinetics of two soybean oil/egg phosphatide lipid emulsions (10% Travamulsion vs 10% Intralipid) from the vascular compartment of the dog. Elimination kinetics were evaluated after bolus injection and after continuous infusion studies. Evaluation of triglyceride and free fatty acid data indicates the emulsions are similar metabolic substrates. Phospholipid and cholesterol data indicate a possible difference in remnant particle removal. At the higher lipid dosages, remnant particles from Travamulsion injection were removed at a faster rate than those from Intralipid.

The ability of soybean oil lipid emulsions to affect essential fatty acid deficiency (EFAD) and plasma fatty acid distribution was studied in neonatal pigs. The test animals were maintained on a fat-free diet prior to administration of lipid emulsion. Plasma and red blood cell (RBC) membrane levels of essential [linoleic (C-18:2 omega 6) and arachidonic (C-20:4 omega 6)] and nonessential [palmitic (C-16, palmitoleic (C-16:1 omega 7), stearic (C-18), and oleic (C-18:1 omega 9)] fatty acids and the triene:tetraene ratio [5,8,11-eicosatrienoic acid (C-20:3 omega 9):arachidonic acid (C-20:4 omega 6)] were monitored to ascertain the establishment of EFAD and its correction. Nonessential fatty acids were studied, as these components of lipid therapy have received little attention. Results indicate that soybean oil emulsions are effective in reversing fatty acid profiles found in EFAD, and both essential and nonessential fatty acids are under strict metabolic control.