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771.
Porcine bone is often used as a substitute for human bone in forensic trauma studies, but little has been published on its comparative mechanical behavior. The factors affecting mechanical properties and therefore selection of bone models are complex and include the age of the animal at death, and physiological loading conditions, the latter being of particular relevance when using a quadrupedal animal as a human substitute. The regional variation in hardness of adult and infant porcine bones was investigated using Vickers’ indentation tests and compared to published data for human limb bones to relate differences to inherent genetic effects and loading influences, and to examine the validity of the porcine‐human model. Significant differences in hardness were observed both along and around the adult porcine humerus and femur, but no significant differences were found along the length of the infant bones. Significant differences were found between the forelimb and hindlimb, but only in the infant specimens. The hardness values for porcine adult cortical bone from the femur (52.23 ± 1.00 kg mm?2) were comparable to those reported in the literature for adult human cortical bone from the fibula, ilium, and calcaneus. These data will help inform subject selection in terms of both species and bone type for use in future trauma studies. 相似文献
772.
Christopher Maier PhD Alba Craig BA Donovan M. Adams PhD 《Journal of forensic sciences》2021,66(1):11-24
Recent discussions have revolved around the concept of ancestry and ancestry estimation; however, the associated terminology and its theoretical underpinnings have not been similarly examined. This research evaluates the concepts (e.g., race, ancestry, ethnicity) currently in use, examines if they are consistent with the groups employed to illustrate them (e.g., Black, European, Hispanic), and looks for patterns in language usage. Articles in the Anthropology, Odontology, and General sections of the Journal of Forensic Sciences between 2009 and 2019 were evaluated for ancestry‐related language use. For each article, the concepts, examples, and bibliographic information were recorded, and the relationship between concept and example was examined. These data were cross‐tabulated to evaluate relationships between the variables. Cramer's V was used to assess the strength of association of these relationships. In this sample, ancestry predominates, especially recently The concept used is significantly associated with all variables except publication date and authors’ institution(s). Despite the prevalence of the ancestry concept, racially based terms for individual groups were common. The use of ancestry, over race, in forensic contexts has been suggested to be a primarily linguistic change; these results may support that assertion. Inconsistent language usage leads to a lack of clarity in meaning among researchers and misinterpretation of the data. It is critical to recognize that inconsistencies exist, but also to understand why they exist. These results underscore the long overdue need for the inclusion of diverse perspectives in forensic anthropology, especially in the current conversations surrounding ancestry and ancestry estimation. 相似文献
773.
Joong Lee PhD Hongseok Kim MSc Tae-Yi Kang MSc Simyub Yook MSc 《Journal of forensic sciences》2023,68(5):1800-1807
We investigated pattern-modified marked cards used in fraudulent gambling cases in Korea. These cards are printed with modifications to some of the repeated marks on the back, revealing the hand on the front and enabling fraudsters to deceive their victims. We proposed a method for identifying the modified part by first enhancing the card's color difference using an image processing technique and then calculating the similarity between the repeated basic patterns with a Siamese network. This method is fast and convenient, as it can determine the deformation with only 1 or 2 cards and can be implemented in mobile applications, allowing law enforcement officers to investigate quickly. The proposed method serves as a useful tool to aid document examiners in making judgments, as it does not require expensive equipment and effectively visualizes the alterations. 相似文献
774.
Li Yen Candy Lee PhD Jiayu Tan BSc Yong Sheng Lee BSc Christopher Kiu-Choong Syn PhD 《Journal of forensic sciences》2023,68(4):1292-1301
The shedder status of a person is an important consideration when evaluating probabilities of DNA transfer during activity-level assessments. As an extension of our previously published study, the shedder statuses of 38 individuals were reassessed 1 year later. The study found that shedder status may change over time for some individuals and was associated with one's gender, number of items touched, and mobile phone usage. In 29% of touch events, no DNA allele was detected and in 99% of touch events, the amount of DNA deposited was <2 ng. The study also found that in 0.6% of touch events, the participant could be excluded as a contributor of the observed DNA profile, with another person being included. Additionally, our investigations suggest that the current three-category system for shedder status classification may require further refinement to better represent the individuals' shedder status in a population. 相似文献
775.
Richard A. Crocombe PhD Greg Giuntini BS David W. Schiering PhD Luisa T. M. Profeta PhD Michael D. Hargreaves PhD Pauline E. Leary PhD Christopher D. Brown PhD Jessamyn Ward Chmura MS 《Journal of forensic sciences》2023,68(5):1570-1600
The need to detect fentanyl and its analogs in the field is an important capability to help prevent unintentional exposure or overdose on these substances, which may result in death. Many portable methods historically used in the field by first responders and other field users to detect and identify other chemical substances, such as hazardous materials, have been applied to the detection and identification of these synthetic opioids. This paper describes field portable spectroscopic methods used for the detection and identification of fentanyl and its analogs. The methods described are automated colorimetric tests including lateral flow assays; vibrational spectroscopy (mid-infrared and Raman); gas chromatography–mass spectrometry; ion mobility spectrometry, and high-pressure mass spectrometry. In each case the background and key details of these technologies are outlined, followed by a discussion of the application of the technology in the field. Attention is paid to the analysis of complex mixtures and limits of detection, including the required spectral databases and algorithms used to interrogate these types of samples. There is also an emphasis on providing actionable information to the (likely) non-scientist operators of these instruments in the field. 相似文献
776.
Hiroki Segawa PhD Yuko T. Iwata PhD Yuki Okada MS Tadashi Yamamuro PhD Kenji Kuwayama PhD Kenji Tsujikawa PhD Tatsuyuki Kanamori PhD 《Journal of forensic sciences》2023,68(4):1352-1358
Zopiclone (ZOP) is a hypnotic drug prescribed to treat insomnia. Due to the chiral nature of ZOP, the psychologically active S-form and inactive R-form need to be determined enantiomerically in a forensic drug analysis. In the present study, a supercritical fluid chromatography (SFC) method was designed with a faster analysis ability than that of previously reported techniques. The SFC–tandem mass spectrometry (SFC–MS/MS) method was optimized using a column with a chiral polysaccharide stationary phase (Trefoil CEL2). ZOP was extracted from pooled human serum using solid-phase extraction (Oasis HLB) and analyzed. The developed SFC–MS/MS method achieved the baseline separation of S-ZOP and R-ZOP within 2 min. The fit-for-purpose method validation indicated that the optimized solid-phase extraction achieved near complete recovery and approximately 70% of the matrix effect. Both the retention time and peak area showed sufficient precision. The lower and upper limits of quantification (LOQ) were 5.7 × 10−2 ng/mL and 25 ng/mL for R-ZOP, and 5.2 × 10−2 ng/mL and 25 ng/mL for S-ZOP. The calibration line was linear in the range from lower LOQ to upper LOQ. The stability test indicated that ZOP in serum stored in a refrigerator (4°C) degraded and about 55% remained in 31 days. The quick analysis of the SFC–MS/MS method makes it a valid option for the enantiomeric analysis of ZOP. 相似文献
777.
Michelle D. Miranda PhD Patrick Buzzini PhD Peter R. De Forest DCrim Sheila Willis PhD 《Journal of forensic sciences》2023,68(5):1835-1842
In forensic science, scientific problem-solving is characterized by the recognition of traces as part of iterative reasoning processes to assign meaning to those traces in order to interpret and reconstruct events. Through a set of fundamental principles, the Sydney Declaration presents a foundation of forensic science through the lens of a scientist. The distinction between a scientist and a technician may require clarification—where a prototypical technician follows a prescribed set of ‘standard operating procedures’ and may be limited in the interpretation of the resultant data, the scientist utilizes knowledge, skills, experience and imagination to identify the issue at hand and develop lines of inquiry for testing and interpretation. This case report draws on the Sydney Declaration in order to highlight the importance of learning about events from careful consideration of both obvious and less obvious traces. A case involving the assault of a police officer is examined to illustrate the use of the Principles: the problem originally defined by investigators at the scene and later by prosecutors resulted in incorrect analysis and interpretation of traces, hampering efforts at an accurate reconstruction of events. This exercise serves to demonstrate that in order to engage in scientific problem-solving, it is necessary to apply observation and reasoning in forensic investigations in order to yield an outcome that can be clearly articulated. The overarching goal is to support the drive to improve forensic science practice, education, and research through a case illustrating the value of the principles of the Sydney Declaration. 相似文献
778.
779.
Does Spending More Get More? Health Care Delivery and Fiscal Implications From a Medicare Fee Bump
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Alice J. Chen Amy J. Graves Matthew J. Resnick Michael R. Richards 《Journal of policy analysis and management》2018,37(4):706-731
While salient features of the Affordable Care Act include insurance expansions and private coverage reforms, various other provisions are embedded within the law. We focus on a temporary 10 percent fee increase for primary care visits supplied to publicly insured (Medicare) beneficiaries. Using administrative and survey data, we assess the price shock's impact on service volume, physician labor supply, and quality of care. Primary care physicians (PCPs) in independent practices demonstrate, at most, a marginal 2 percent increase in new patient visits while horizontally and vertically integrated PCPs show no change. Both PCP organizational types witness declines in established patient visits, on average, but there is marked heterogeneity: established patient visits increase by 1 to 2 percent among PCPs with fewer Medicare claims in the pre‐period. The Medicare fee bump did not observably impact other labor supply outcomes and quality of care margins. We estimate that the policy introduced a $1.5 billion transfer from taxpayers to providers during the initiative's first three years. 相似文献
780.