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111.
Julie J. Jabaley John R. Lutzker Daniel J. Whitaker Shannon Self-Brown 《Journal of family violence》2011,26(5):377-385
Innovative handheld technologies are changing the possibilities for public health interventions. The present research describes a preliminary examination of the iPhone? when used as an assessment tool and an enhancement to an evidence-based, in-home child safety intervention. Three families with young children received an augmented version of the Safety module of SafeCare, a home-visiting child maltreatment prevention program. Specifically, parents were trained to use an iPhone to video rooms in their homes, as well as communicate feedback, logistics, and safety content between the home visitor and parent. The effectiveness of iPhone and video was examined using a multiple baseline design across in-home settings replicated across families. Home hazards were reduced dramatically across rooms and across participants. Face-to-face time of the home visitor was progressively reduced and replaced by video data collection. These data suggest smartphones are promising for data collection and for augmenting face-to-face interactions. Implications for reducing costs as smartphones become increasingly ubiquitous and for engaging and retaining participants are discussed. 相似文献
112.
In this paper we examine the legal aspects of corporate computer usage policies including their creation, management, and their relevance to corporate computer forensic investigations. Misuse of corporate computing facilities cannot only lead to a reduction in employee productivity and network bandwidth, but can also increase the risk of infection of such facilities by computer viruses and other malicious code. Moreover, it may lead to the risk of liability and legal action. 相似文献
113.
Shawn Donnelly Josette E. Marrero Trevor Cornell Kevin Fowler John Allison Ph.D. 《Journal of forensic sciences》2010,55(1):129-135
Abstract: Anyone with a computer, scanner, and color printer has the capability for creating documents such as identification cards, passports, and counterfeit currency. Laser desorption mass spectrometry (LDMS) has been demonstrated as a powerful tool for colorant analysis. Inkjet printers are now moving largely toward the use of pigments as colorants; their insolubility makes analysis by simpler methods such as thin‐layer chromatography no longer an option. Recent developments in pigmented inkjet printer inks, such as gloss optimizers that coat pigment particles, may prohibit colorant analysis by LDMS. We demonstrate here that pigments used in inks from two Epson printers can be detected and analyzed by LDMS. Also, LDMS spectra of various colors created using a 4‐cartridge (cyan/magenta/yellow/black, CMYK) inkset are evaluated, to begin to develop an approach for unraveling LDMS data from real samples, to determine the number of inks used by a printer, and the chemical composition of the colorants. 相似文献
114.
Wei Chu Ph.D. John Song M.S. Theodore Vorburger Ph.D. James Yen Ph.D. Susan Ballou M.S. Benjamin Bachrach Ph.D. 《Journal of forensic sciences》2010,55(2):341-347
Abstract: A procedure for automated bullet signature identification is described based on topography measurements using confocal microscopy and correlation calculation. Automated search and retrieval systems are widely used for comparison of firearms evidence. In this study, 48 bullets fired from six different barrel manufacturers are classified into different groups based on the width class characteristic for each land engraved area of the bullets. Then the cross‐correlation function is applied both for automatic selection of the effective correlation area, and for the extraction of a 2D bullet profile signature. Based on the cross‐correlation maximum values, a list of top ranking candidates against a ballistics signature database of bullets fired from the same model firearm is developed. The correlation results show a 9.3% higher accuracy rate compared with a currently used commercial system based on optical reflection. This suggests that correlation results can be improved using the sequence of methods described here. 相似文献
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With increasing frequency, relatively small, fragmentary evidence thought to be osseous or dental tissue of human origin is submitted to the forensic laboratory for DNA analysis with the request for positive identification. Prior to performing DNA analysis, however, it is prudent to first perform a presumptive test or "screen" to determine whether the questioned material may be eliminated from further consideration. When material is shown not to be consistent with bone/teeth, DNA testing is not performed. When such determinations cannot be made from gross morphological features, elemental analysis can be indicative. This presumptive test is made possible by applying scanning electron microscopy/energy dispersive X-ray spectroscopy (SEM/EDS) in conjunction with an X-ray spectral database recently developed by the FBI laboratory. This database includes spectra for many different materials including known examples of bone and tooth from many different contexts and representing the full range of taphonomic conditions. Results of SEM/EDS analysis of evidence can be compared to these standards to determine if they are consistent with bone and/or tooth and, if not, then what the material might represent. Analysis suggests that although the proportions and amounts of calcium and phosphorus are particularly important in differentiating bone and tooth from other materials, other minor differences in spectral profile can also provide significant discrimination. Analysis enables bone and tooth to be successfully distinguished from other materials in most cases. Exceptions appear to be ivory, mineral apatite, and perhaps some types of corals. 相似文献
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Evaluation of laser desorption mass spectrometry and UV accelerated aging of dyes on paper as tools for the evaluation of a questioned document 总被引:1,自引:0,他引:1
Laser desorption mass spectrometry (LDMS) may be used for the detection and identification of dyes found in inks. Naturally-aged and artificially-aged blue and black ballpoint pen inks containing the cationic dye methyl violet were analyzed on paper. The average molecular weight of the dye sample was calculated from LD mass spectral data and plotted versus time. The resulting aging curves demonstrate that, as dye degradation increases, the average molecular weight of the dye decreases. Typical variables involved in ink aging, such as the type of paper and ink formulation, were investigated. Results show that these variables influence the rate of dye degradation. Furthermore, UV accelerated aging has been developed and tested as an alternative to thermal approaches. 相似文献
120.