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281.
The photographic preservation of fingermark impression evidence found on ammunition cases remains problematic due to the cylindrical shape of the deposition substrate preventing complete capture of the impression in a single image. A novel method was developed for the photographic recovery of fingermarks from curved surfaces using digital imaging. The process involves the digital construction of a complete impression image made from several different images captured from multiple camera perspectives. Fingermark impressions deposited onto 9‐mm and 0.22‐caliber brass cartridge cases and a plastic 12‐gauge shotgun shell were tested using various image parameters, including digital stitching method, number of images per 360° rotation of shell, image cropping, and overlap. The results suggest that this method may be successfully used to recover fingermark impression evidence from the surfaces of ammunition cases or other similar cylindrical surfaces.  相似文献   
282.
The medical usefulness of smartphones continues to evolve as third‐party applications exploit and expand on the smartphones’ interface and capabilities. This technical report describes smartphone still‐image capture techniques and video‐sequence recording capabilities during postmortem monocular indirect ophthalmoscopy. Using these devices and techniques, practitioners can create photographic documentation of fundal findings, clinically and at autopsy, without the expense of a retinal camera. Smartphone image acquisition of fundal abnormalities can promote ophthalmological telemedicine—especially in regions or countries with limited resources—and facilitate prompt, accurate, and unbiased documentation of retinal hemorrhages in infants and young children.  相似文献   
283.
Fifty-three head hair specimens were collected from 38 males with a history of cannabis use documented by questionnaire, urinalysis and controlled, double blind administration of delta9-tetrahydrocannabinol (THC) in an institutional review board approved protocol. The subjects completed a questionnaire indicating daily cannabis use (N=18) or non-daily use, i.e. one to five cannabis cigarettes per week (N=20). Drug use was also documented by a positive cannabinoid urinalysis, a hair specimen was collected from each subject and they were admitted to a closed research unit. Additional hair specimens were collected following smoking of two 2.7% THC cigarettes (N=13) or multiple oral doses totaling 116 mg THC (N=2). Cannabinoid concentrations in all hair specimens were determined by ELISA and GCMSMS. Pre- and post-dose detection rates did not differ statistically, therefore, all 53 specimens were considered as one group for further comparisons. Nineteen specimens (36%) had no detectable THC or 11-nor-9-carboxy-THC (THCCOOH) at the GCMSMS limits of quantification (LOQ) of 1.0 and 0.1 pg/mg hair, respectively. Two specimens (3.8%) had measurable THC only, 14 (26%) THCCOOH only, and 18 (34%) both cannabinoids. Detection rates were significantly different (p<0.05, Fishers' exact test) between daily cannabis users (85%) and non-daily users (52%). There was no difference in detection rates between African-American and Caucasian subjects (p>0.3, Fisher's exact test). For specimens with detectable cannabinoids, concentrations ranged from 3.4 to >100 pg THC/mg and 0.10 to 7.3 pg THCCOOH/mg hair. THC and THCCOOH concentrations were positively correlated (r=0.38, p<0.01, Pearson's product moment correlation). Using an immunoassay cutoff concentration of 5 pg THC equiv./mg hair, 83% of specimens that screened positive were confirmed by GCMSMS at a cutoff concentration of 0.1 pg THCCOOH/mg hair.  相似文献   
284.
The findings from a growing body of research reveal that incarceration is detrimental for both physical and mental health. Incarceration, however, is typically conceptualized and operationalized as a dichotomy; individuals either have, or have not, been incarcerated. Considering that incarceration can range from one day to several years, a dichotomous measure may be overlooking important variations across lengths of exposure. In addition, most inmates are incarcerated more than once. In this study, we help to fill this gap by examining the relationship between incarceration dosage, measured as time served and number of spells, and mental health among a sample of young adults from the National Longitudinal Study of Youth 1997. By using fixed‐effects modeling, we find that the number of spells and the months incarcerated are positively related to mental health symptoms and the likelihood of depression. The association, however, is contingent on whether a respondent is currently or formerly incarcerated. Among current inmates, more time served is expected to improve mental health and the number of spells is unrelated to either outcome.  相似文献   
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