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691.
Liu JY Zhong C Holt A Lagace R Harrold M Dixon AB Brevnov MG Shewale JG Hennessy LK 《Journal of forensic sciences》2012,57(4):1022-1030
Abstract: The AutoMate Express? Forensic DNA Extraction System was developed for automatic isolation of DNA from a variety of forensic biological samples. The performance of the system was investigated using a wide range of biological samples. Depending on the sample type, either PrepFiler? lysis buffer or PrepFiler BTA? lysis buffer was used to lyse the samples. After lysis and removal of the substrate using LySep? column, the lysate in the sample tubes were loaded onto AutoMate Express? instrument and DNA was extracted using one of the two instrument extraction protocols. Our study showed that DNA was recovered from as little as 0.025 μL of blood. DNA extracted from casework‐type samples was free of detectable PCR inhibitors and the short tandem repeat profiles were complete, conclusive, and devoid of any PCR artifacts. The system also showed consistent performance from day‐to‐day operation. 相似文献
692.
Soderquist TJ Chesniak OM Witt MR Paramo A Keeling VA Keleher JJ 《Forensic science international》2012,218(1-3):101-105
Hair testing for drugs of abuse is performed in Lombardy by eleven analytical laboratories accredited for forensic purposes, the most frequent purposes being driving license regranting and workplace drug testing. Individuals undergoing hair testing for these purposes can choose the laboratory in which the analyses have to be carried out. The aim of our study was to perform an interlaboratory exercise in order to verify the level of standardization of hair testing for drugs of abuse in these accredited laboratories; nine out of the eleven laboratories participated in this exercise. Sixteen hair strands coming from different subjects were longitudinally divided in 3-4 aliquots and distributed to participating laboratories, which were requested to apply their routine methods. All the participants analyzed opiates (morphine and 6-acetylmorphine) and cocainics (cocaine and benzoylecgonine) while only six analyzed methadone and amphetamines (amphetamine, methamphetamine, MDMA, MDA and MDEA) and five Δ(9)-tetrahydrocannabinol (THC). The majority of the participants (seven labs) performed acidic hydrolysis to extract the drugs from the hair and analysis by GC-MS, while two labs used LC-MS/MS. Eight laboratories performed initial screening tests by Enzyme Multiplied Immunoassay Technique (EMIT), Enzyme-linked Immunosorbent Assay (ELISA) or Cloned Enzyme Donor Immunoassay (CEDIA). Results demonstrated a good qualitative performance for all the participants, since no false positive results were reported by any of them. Quantitative data were quite scattered, but less in samples with low concentrations of analytes than in those with higher concentrations. Results from this first regional interlaboratory exercise show that, on the one hand, individuals undergoing hair testing would have obtained the same qualitative results in any of the nine laboratories. On the other hand, the scatter in quantitative results could cause some inequalities if any interpretation of the data is required. 相似文献
693.
Chelsea E. Johnson M.S. Paul Martin Ph.D. Katherine A. Roberts Ph.D. Tatiana Trejos Ph.D. Ruthmara Corzo B.S. Jose R. Almirall Ph.D. Alan M. Safer Ph.D. 《Journal of forensic sciences》2018,63(1):66-79
This study applies Raman microspectroscopy to differentiate the chemical components in printing inks of different brands, colors, and type using the 532 nm and 785 nm excitation wavelengths. Spectra were collected from 319 inks (78 inkjet, 76 toner, 79 offset, and 86 intaglio) representing various colors. Comparisons were performed to calculate discrimination capability percentages for each ink type. Overall, Raman microspectroscopy differentiates according to the following hierarchy: intaglio (96%), inkjet (92%), offset (90%), and toner (61%). The ability of Raman microspectroscopy to differentiate between same‐colored inks from different brands was dependent on the color and ink analyzed. Based on ink color, the discrimination capability ranged from 75 to 94% (inkjet), 0 to 86% (toner), and 0 to 77% (offset). Copper phthalocyanine was detected in cyan inks and various intaglio inks, while carbon black was identified in black inkjet, offset, and intaglio inks. 相似文献
694.
Although Louis Brandeis is rightly regarded as a champion offederalism, this article suggests that his famous depictionof the American states as "laboratories" of democracy in facthas little to do with federalism and in fad rests on an understandingof public policy inimical to federal diversity. More specifically,it argues that Brandeis's choice of metaphor largely reflectshis hope for scientifically based public policy, which in turnreflected the influence of Scientific Management upon his thought.The article concludes that abandoning Brandeis's metaphor wouldbe useful in rethinking the relations among states in the diffusionof innovations. 相似文献
695.
696.
Levinton-Shamuilov G Cohen Y Azoury M Chaikovsky A Almog J 《Journal of forensic sciences》2005,50(6):1367-1371
Genipin, a hydrolytic product of geniposide extracted from gardenia fruit, was thoroughly studied as a potential fingerprint reagent, and optimal conditions for fingerprint development have been determined. Latent fingerprints on paper items that have been treated with a non-ink running formulation containing 0.17% of the reagent, showed up as both colored and fluorescent images. On brown wrapping paper and on papers with highly luminescent backgrounds, genipin developed more visible and clearer prints than did classical reagents such as ninhydrin or DFO. Another potential advantage of genipin is that it is totally harmless and an environmentally friendly reagent. 相似文献
697.
Carr A 《Journal of interpersonal violence》2005,20(4):426-435
The prevention of future violence through engaging violent adolescents in multisystemic therapy and the treatment of trauma with exposure therapy are two of the most important scientific advances in the field of interpersonal violence in the past 20 years. A particularly significant methodological innovation is the development of reliable and valid measures of childhood and adult attachment because attachment deficits and their remediation are central to understanding and treating perpetrators of violence. In the coming decades, we need to refine existing treatment programs to make them effective for cases currently classified as treatment resistant. This will involve psychotherapy process research on the interaction between therapeutic mechanisms of change and unique personal vulnerabilities of treatment-resistant cases. 相似文献
698.
Subrata?Ghatak Alan?MulhernEmail author Chris?Stewart 《Economic Change and Restructuring》2005,38(2):129-146
Employing a probit, logit and gompit model this paper demonstrates that small firm development, represented by a group of
structural, behavioral and performance variables determine regional location in Poland. The paper uses original data that
samples the small firm stratum in two contrasting regions, Pomorskie and Lubelskie. The following variables were shown to
be significantly correlated with regional location: legal structure, subcontracting, technological level of the products of
the firm, average wage and intention to expand turnover. 相似文献
699.
A bullet signature measurement system based on a stylus instrument was developed at the National Institute of Standards and Technology (NIST) for the signature measurements of NIST RM (Reference Material) 8240 standard bullets. The standard bullets are developed as a reference standard for bullet signature measurements and are aimed to support the recently established National Integrated Ballistics Information Network (NIBIN) by the Bureau of Alcohol, Tobacco and Firearms (ATF) and the Federal Bureau of Investigation (FBI). The RM bullets are designed as both a virtual and a physical bullet signature standard. The virtual standard is a set of six digitized bullet signatures originally profiled from six master bullets fired at ATF and FBI using six different guns. By using the virtual signature standard to control the tool path on a numerically controlled diamond turning machine at NIST, 40 RM bullets were produced. In this paper, a comparison parameter and an algorithm using auto-and cross-correlation functions are described for qualifying the bullet signature differences between the RM bullets and the virtual bullet signature standard. When two compared signatures are exactly the same (point by point), their cross-correlation function (CCF) value will be equal to 100%. The measurement system setup, measurement program, and initial measurement results are discussed. Initial measurement results for the 40 standard bullets, each measured at six land impressions, show that the CCF values for the 240 signature measurements are higher than 95%, with most of them even higher than 99%. These results demonstrate the high reproducibility for both the manufacturing process and the measurement system for the NIST RM 8240 standard bullets. 相似文献
700.
In spite of increasing number of cremations in the U.S., little is known about weights of cremated remains. This research was undertaken in order to add to the limited literature on cremains weights and to explore variation. Weights of cremated remains were obtained from the East Tennessee Crematorium. The sample consists of 151 males and 155 females. Age, sex, and race were obtained for each individual. Males are about 1000 g heavier than females. Both sexes lose weight with age, but females lose weight at about twice the rate of males. East Tennessee cremation weights were compared with those from Florida reported by Warren and Maples, and those from Southern California reported by Sonek. East Tennessee results were also compared with an earlier study on ash weight of anatomical human skeletons carried out by Trotter and Hixon. East Tennessee cremations weigh about 500 g more than the samples from Florida and California, and about the same as the earlier anatomical samples. We hypothesize that variation reflects variation in body weight and activity. This variation must be taken into account when cremation weights are at issue. 相似文献