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171.
The Journal of Technology Transfer - Despite the growing interest in understanding innovative activities, an important limitation of the current literature on innovation—both public and... 相似文献
172.
Nicole Loper B.Sc. Jack Garland B.Med. Benjamin Ondruschka M.D. Charley Glenn M.D. Kilak Kesha M.D. Simon Stables M.B.Ch.B. Rexson Tse M.D. 《Journal of forensic sciences》2020,65(5):1563-1567
Correctly assessing heart weight can be critical at postmortem examination. The current international guidelines advocate using the short-axis method in dissecting the heart and the heart weighed when the blood is emptied. However, it did not specify at what point the heart should be weighed or how the blood should be emptied. This study compared heart weights at three different time points during the heart examination (immediately after dissecting out of the pericardial sac with blood still in chambers, blood washed/removed from heart chambers without the heart opened, and the heart completely opened, blood emptied, and pad dried). This was to illustrate the variation in measurement and potential errors when the heart is weighed at different time of dissection. The results show that there were statistical and clinical significant differences between the heart weights at each weighing points. We recommend the heart to be completely dissected with any blood and residual washing/rinsing water emptied before being weighed. Although performed in this study, the effect of pad drying the heart on heart weight was not explored and was a limitation in this study. 相似文献
173.
Marloes E. M. Vester M.D. Ph.D. Kurt B. Nolte M.D. Ph.D. Gary M. Hatch M.D. Chandra Y. Gerrard M.P.H. B.S. Reinoud D. Stoel Ph.D. Rick R. van Rijn M.D. Ph.D. 《Journal of forensic sciences》2020,65(5):1568-1573
Postmortem computed tomography (PMCT) is integrated into the evaluation of decedents in several American medical examiner offices and medicolegal death investigative centers in many other countries. We retrospectively investigated the value of PMCT in a series of firearm homicide cases from a statewide centralized medical examiner’s office that occurred during 2016. Autopsies were performed or supervised by board-certified forensic pathologists who reviewed the PMCT scans prior to autopsy. PMCT scans were re-evaluated by a forensic radiologist blinded to the autopsy findings and scored by body region (head–neck, thoracoabdominal, and extremities). Injury discrepancies were scored using a modified Goldman classification and analyzed with McNemar’s test. We included 60 males and 20 females (median age 31 years, range 3–73). Based on PMCT, 56 (79.1%) cases had injuries relevant to the cause of death in a single body region (24 head–neck region, 32 thoracoabdominal region). Out of these 56 cases, 9 had a missed major diagnosis by PMCT outside that region, including 6 extremity injuries visible during standard external examination. Yet all had evident lethal firearm injury. We showed that PMCT identifies major firearm injuries in homicide victims and excludes injuries related to the cause of death in other regions when a single body region is injured. Although PMCT has a known limited sensitivity for soft tissue and vascular pathology, it can be combined with external examination to potentially reduce or focus dissections in some of these cases depending on the circumstances and medicolegal needs. 相似文献
174.
Adam Lanzarotta Ph.D. Michael D. Thatcher B.S. Lisa M. Lorenz B.S. JaCinta S. Batson M.S. 《Journal of forensic sciences》2020,65(5):1443-1449
A simple, quick, selective, sensitive, and effective field-friendly method capable of being used by nonexperts has been developed for detecting mitragynine in Mitragyna speciosa (kratom) using surface-enhanced Raman spectroscopy (SERS). Over 100 samples and blanks (known to be either positive or negative for the presence of mitragynine) were examined in duplicate using five identical handheld Raman spectrometers, which provided a data set of over 1,000 examinations. Based on the results of these analyses, the method yielded a true-positive rate of 99.3%, a true-negative rate of 97.9%, a false-positive rate of 2.1%, and a false-negative rate of 0.7%. The average minimum detectable concentration (Cm) of mitragynine that reproducibly yielded a match for one of the library spectra on all five instruments was determined to be 342 ng/mL (ppb). This Cm value is a conservative estimate considering that the extraction process was not fully optimized by this study, which was not necessary since the Cm value achieved was well below typical mitragynine concentrations in kratom (1.3–2.3%). The method is ideal (i) for prioritizing samples for additional testing using other more time-consuming laboratory-based techniques needed to detect and quantify mitragynine and (ii) for field use at international mail facility (IMF) satellite laboratories to help interdict kratom and prevent this dangerous product from reaching the U.S. supply chain. 相似文献
175.
Dalia M. Al-Saif M.B.B.S. S.B.F.L.M. Maram A. Al-Farayedhi M.B.B.S. S.B.F.L.M Ghadah A. Al-Shamsi M.B.B.S. S.B.F.L.M. Marwah I. Al-Bayat M.B.B.S. S.B.F.L.M. Osama M. Almadani M.D. Ph.D. F.F.F.L.M. Magdy A. Kharoshah M.B.Bch. M.Sc. M.D F.F.F.L.M. 《Journal of forensic sciences》2020,65(5):1574-1578
Examination of the female external genitalia to assess for sexual abuse is performed in living individuals, and the interpretation of the findings is based on evidence-based studies. However, in the deceased, no such studies are available, and postmortem changes could present as suspicious findings that can be mistaken for trauma. Patches of discoloration in the hymen were reported previously in one case as hypostasis (i.e., livor and lividity), and based on this finding, it was listed as a finding that is not associated with trauma. This was a retrospective study that was conducted in the Center of Forensic and Legal Medicine in Dammam, Saudi Arabia over a 4-year period. The study included 30 deceased women in whom photographic documentation of their external genitalia was assessed for postmortem changes. The postmortem interval ranged from less than 24 h to more than 100 days, and the ages of these deceased women were in the 20–40 year-old age group. In cases where the hymen, vagina, and/or fossa navicularis were clearly visible, none of these areas showed any hypostatic discoloration. A comparison between antemortem and postmortem appearance of the hymen in one case clearly showed the absence of hypostatic changes in the hymen. In conclusion, any discoloration of the external genitalia that is detected in a female decedent requires serious consideration. 相似文献
176.
When a bullet punctures a surface, it leaves behind a bullet impact, which can be analyzed in order to determine the origin and trajectory path from which a bullet was discharged using many different scientific methods to reconstruct a shooting scene. The purpose of the research was to test the accuracy and repeatability of reconstructing the impact angle of single bullet impacts using the ellipse method. The research was conducted by firing various calibers of ammunition into drywall panels positioned at varying angles of incidence from 88° until ricochet occurred. This was done in order to determine which caliber type and angle of incidence are most accurate and precise for reconstructing a shooting scene. The study examined four caliber types fired into drywall panels, with 5 repeated shots for each of the 11 angles of incidence (n = 220). Furthermore, 31 participants partook in the study to estimate a bullet impact angle of incidence utilizing the ellipse method. The results show that the best performance (accuracy and repeatability) is seen with the measurements of the 0.45 caliber ammunition. When angle of incidences is low (<64°), the performance (accuracy and repeatability) was seen to be better in all caliber ammunitions. Overall, the data provided for single bullet impacts deposited in drywall show that the ellipse method is useful in providing measurements for most crime scene reconstruction purposes and has also demonstrated that results vary depending on the type of ammunition, firearm, and angle of incidence being examined. 相似文献
177.
178.
Sophia K. Chiu M.D. M.P.H. Jessica F. Li M.S.P.H. Kurt B. Nolte M.D. 《Journal of forensic sciences》2020,65(4):1324-1327
Recent increases in deaths in the United States from synthetic opioids such as fentanyl and fentanyl analogues (fentanyls) have raised concerns about possible occupational exposures to these potent agents. Medicolegal death investigators and autopsy suite staff might perform job tasks involving exposure to fentanyls. The potential for exposure to fentanyls among medicolegal death investigators and autopsy technicians at a state medical examiner's office was evaluated through review of caseload characteristics, injury and illness logs, and procedures and policies and discussions with management and employee representatives. The evaluation showed that this medical examiner's office had low potential for work-related exposure to fentanyls; its standard operating procedures and personal protective equipment requirements should reduce the potential for occupational exposure. Medicolegal death investigation agencies can develop and implement guidance to control exposures and provide workforce education and training to reduce the potential for work-related exposure to fentanyls. 相似文献
179.
This article examines the well-documented relationship between early initiation or onset of criminal behavior and a heightened
risk of involvement in offending. Previous research examining this question conducted by Nagin and Farrington (Criminology
30:235–260, 1992a; Criminology 30:501–523, 1992b) used data from the Cambridge Study in Delinquent Development and found that: (1) onset age was correlated with offending
involvement; and (2) the correlation could be explained by stable individual differences in the propensity to offend rather
than a causal effect of early onset age. In this study, similar analytic methods are applied to data from the Second Philadelphia
Birth Cohort. This data set consists of all 13,160 males born in Philadelphia in 1958 who resided in the city continuously
from ages 10 to 18, slightly more than half of whom were non-white. Information from each of the youths was collected from
schools, juvenile justice agencies, other official sources and surveys. In a model that mimics previous analyses, we initially
found that an early age of onset is associated with greater subsequent involvement in delinquent behavior. When unobserved
criminal propensity was controlled, however, we found that a late rather than an early onset of delinquency was related to
future offending. In finding a state dependent effect for age of onset, our findings are contrary to propensity theory in
criminology. In finding that it is late rather early onset which puts youth at risk for future offending, our findings are
contrary to developmental/life course theory. Our results are more compatible with traditional criminological theory that
is friendly to state dependence processes, though they too have not to date articulated why a late onsetting of offending
might be particularly criminogenic.
Sarah Bacon is an Assistant Professor in the College of Criminology and Criminal Justice at the Florida State University, Tallahassee, Florida. She received her Ph.D. from the University of Maryland. Her research interests focus on quantitative methods, testing criminological theory, and capital punishment. This paper is an extension of work conducted for her M.A. thesis at the University of Maryland. Raymond Paternoster is Professor in the Department of Criminology and Criminal Justice at the University of Maryland and Faculty Affiliate of the Maryland Population Research Center, College Park, Maryland. He received his Ph.D. from Florida State University. His research interests focus on testing criminological theory, the relationship between events in adolescence and delinquency, and capital punishment. Robert Brame is Professor in the Department of Criminal Justice at the University of North Carolina Charlotte, Charlotte, North Carolina. He received his Ph.D. from the University of Maryland. His current research interests focus on domestic violence, the use of criminal records for screening purposes, linkages between adolescent employment and criminal behavior, and capital punishment. 相似文献
Raymond PaternosterEmail: |
Sarah Bacon is an Assistant Professor in the College of Criminology and Criminal Justice at the Florida State University, Tallahassee, Florida. She received her Ph.D. from the University of Maryland. Her research interests focus on quantitative methods, testing criminological theory, and capital punishment. This paper is an extension of work conducted for her M.A. thesis at the University of Maryland. Raymond Paternoster is Professor in the Department of Criminology and Criminal Justice at the University of Maryland and Faculty Affiliate of the Maryland Population Research Center, College Park, Maryland. He received his Ph.D. from Florida State University. His research interests focus on testing criminological theory, the relationship between events in adolescence and delinquency, and capital punishment. Robert Brame is Professor in the Department of Criminal Justice at the University of North Carolina Charlotte, Charlotte, North Carolina. He received his Ph.D. from the University of Maryland. His current research interests focus on domestic violence, the use of criminal records for screening purposes, linkages between adolescent employment and criminal behavior, and capital punishment. 相似文献
180.