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951.
This study developed a composite machine learning algorithm for attribution of materials of forensic interest (like ammonium nitrate) to original sources. k-nearest neighbor and random forest models were used for source elimination and classification, respectively, in a two-step, composite algorithm based on particle color, size/shape, and trace element concentration features. Novel approaches for simulation to supplement within-source reference features based on empirically measured multi-lot analyses, an improved hold-one-lot-out method for cross-validation, an assessment of the likelihood of the presence of a reference sample, fusion of the source probabilities from the respective classification models, and the calculation of metrics for assessing ensemble sourcing performance are described. Excellent sourcing predictions were obtained; the sourcing algorithm identified the correct source as the top choice 89% of the time, and the correct source was identified to be an average of 2.7 times more likely than the most likely incorrect source. 相似文献
952.
Jessica E. Sanger Ciarleglio M.A. Kristen M. Perez M.S. Haley L. Motola M.S. Elizabeth A. DiGangi Ph.D. 《Journal of forensic sciences》2020,65(5):1698-1703
Dermestid beetles (Dermestes maculatus De Geer 1774) are small carrion insects characterized by a rounded or oval-shaped body and white abdomen with black markings. Given their natural propensity to consume soft tissue throughout various stages of decomposition, biological anthropologists have sought to use dermestids as a forensic processing method in addition to traditional chemical tissue removal techniques. Although useful, most of the existing academic literature regarding the upkeep of dermestid colonies for skeletal remains processing either lack specificity or are outdated. Additionally, nonacademic sources that contain information regarding dermestid maintenance are often disjointed, resulting in a difficulty to replicate habitat construction and ideal environmental conditions. Therefore, this technical note presents recommendations for anthropologists interested in establishing and maintaining a D. maculatus population. These recommendations are based on our experiences using several dermestid colonies to process five unembalmed human heads, procured from an anatomical gift company for a larger study on gunshot trauma. Aspects of the dermestids’ environment that are crucial for the management of a healthy colony include the type of bedding, food, water, and containment method used, in addition to maintaining appropriate temperature ranges (24–27°C) and humidity levels (35–73%). Although habitat construction and dermestid maintenance involve materials that are relatively inexpensive and readily available, setting up and maintaining a D. maculatus colony can be laborious and time consuming and should only be undertaken when the volume of casework is such that this investment would be offset. 相似文献
953.
Douwe van der Heide M.D. Irena Boskovic Ph.D. Peter van Harten M.D. Ph.D. Harald Merckelbach Ph.D. 《Journal of forensic sciences》2020,65(4):1371-1375
Clinicians tend to overestimate their ability to recognize feigning behavior in psychiatric patients, especially if it concerns patients who have been admitted for observation. Feigning can be either externally motivated (e.g., for financial compensation, known as malingering) or internally motivated (e.g., to assume the “sick role,” known as factitious disorder). Persistent presentation of severe symptoms is usually associated with the factitious disorder. We present two patients with strong external incentives who consistently and convincingly feigned severe psychiatric symptoms during a protracted period of inpatient observation in a specialized center; both were engaged in a procedure for medical asylum. The first case presented with the clinical picture of a psychotic depression with severe motor symptoms, and the second case showed symptoms of a chronic post-traumatic stress disorder with secondary psychotic symptoms. Both cases were thoroughly investigated but feigning was overlooked, and unnecessary and harmful treatment interventions were given. To prevent iatrogenic damage, we recommend a critical attitude that takes malingering as an option into account in settings where patients are often involved in high stake legal procedures. A clinical sign that might indicate feigning is therapy-resistant symptoms. To rule out feigning a comprehensive, multimethod approach is required, but an active stance toward collateral information is essential. Specialized psychological tests may be useful for preliminary screening, but for their use in culturally diverse populations as in refugee mental health more research is needed. 相似文献
954.
Breana N. Peace M.S. James T. Pokines Ph.D. Peter M. Cummings M.Sc. M.D. Allen G. Harbaugh Ph.D. 《Journal of forensic sciences》2020,65(5):1416-1423
Hacking trauma is prevalent in forensic cases involving genocide and dismemberment, but research into the identification of this type of trauma is lacking. The present study examines characteristics of hacking and blunt force skeletal trauma in order to determine if there is a point at which blunt force trauma becomes distinguishable from hacking trauma. Ten implements with a range of blade angles (i.e., the striking surface of the implement) were used in conjunction with a controlled-force hacking device to impact 100 limb bones of white-tailed deer (Odocoileus virginianus). Observations of the trauma included the occurrence and degree of fragmentation, the entrance widths of the impacts, and composite scores of six hacking characteristics, especially the distinctive V-shaped kerf. ANOVA tests and regression analyses were used to assess the relationships between these characteristics and the blade angles. A significant relationship (p-value = 0.011) was found between the composite hacking scores and the blade angles, indicating that blunt force and hacking trauma can be distinguished. The entrance widths of the impacts exhibited a significant relationship with the blade angles (p-value = 0.037). There was also a significant relationship between the visibility of a V-shaped kerf in the bones (p-value = 0.003), with visibility decreasing around the 60° blade angle. These data should assist in establishing guidelines to differentiate hacking and blunt force skeletal trauma in cases where the implement is on a spectrum between sharp and blunt. 相似文献
955.
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
956.
ABSTRACTStudies have demonstrated the efficacy of the Scharff technique for gathering human intelligence, but little is known about how this efficacy might vary among different samples of practitioners. In this training study we examined a sample of military officers (n?=?37). Half was trained in the Scharff technique and compared against officers receiving no Scharff training. All officers received the same case file describing two sources holding information about a terrorist attack. University students (n?=?74) took the role of the semi-cooperative sources. Scharff-trained officers adhered to the training as they (1) aimed to establish the ‘knowing-it-all’ illusion, (2) posed claims as a means of eliciting information, and (3) asked fewer explicit questions. The ‘untrained’ officers asked many explicit questions, questioned the reliability of the provided information, pressured the source, and displayed disappointment with the source's contribution. Scharff-trained officers were perceived as less eager to gather information and left their sources with the impression of having provided comparatively less new information, but collected a similar amount of new information as their untrained colleagues. The present paper both replicates and advances previous work in the field, and marks the Scharff technique as a promising technique for gathering human intelligence. 相似文献
957.
Psychological Injury and Law - The extent to which persons may feign or malinger psychological symptoms is an important concern for civil litigation, specifically in the context of personal injury.... 相似文献
958.
苏联解体20年后,几乎所有的前共产主义国家都程度不同地完成了从计划经济向市场经济的转型.然而,仍然有些转型国家在这一进程中落在后面,其中就有前苏联的5个中亚加盟共和国.对于这些既不同于俄罗斯和东欧,更不同于西方发达国家的国家来说,实现转型没有明显的参照模式.本文的目的就是分析在东亚地区取得成功的"发展型政权"是否也能够为中亚经济体的发展提供一个参考模式. 相似文献
959.
Robert A. Lonardo Peggy C. Giordano Monica A. Longmore Wendy D. Manning 《Journal of youth and adolescence》2009,38(3):367-383
Adolescent networks include parents, friends, and romantic partners, but research on the social learning mechanisms related
to delinquency has not typically examined the characteristics of all three domains simultaneously. Analyses draw on data from
the Toledo Adolescent Relationships Study (n = 957), and our analytic sample contains 51% male and 49% female as well as 69% white, 24% African-American, and 7% Latino
respondents. Parents,’ peers,’ and partners’ deviance are each related to respondents’ delinquency, and affiliation with a
greater number of deviant networks is associated with higher self-reported involvement. Analyses that consider enmeshment
type indicate that those with both above average romantic partner and friend delinquency report especially high levels of
self-reported involvement. In all comparisons, adolescents with deviant romantic partners are more delinquent than those youths
with more prosocial partners, regardless of friends’ and parents’ behavior. Findings highlight the importance of capturing
the adolescent’s entire network of affiliations, rather than viewing these in isolation, and suggest the need for additional
research on romantic partner influences on delinquent behavior and other adolescent outcomes.
相似文献
Robert A. LonardoEmail: |
960.
Willeke A. Manders Jan M. A. M. Janssens William L. Cook Johan H. L. Oud Eric E. J. De Bruyn Ron H. J. Scholte 《Journal of youth and adolescence》2009,38(10):1328-1338
Considerable research has focused on the reliability and validity of informant reports of family behavior, especially maternal
reports of adolescent problem behavior. None of these studies, however, has based their orientation on a theoretical model
of interpersonal perception. In this study we used the social relations model (SRM) to examine family members’ reports of
each others’ externalizing and internalizing problem behavior. Two parents and two adolescents in 69 families rated each others’
behavior within a round-robin design. SRM analysis showed that within-family perceptions of externalizing and internalizing
behaviors are consistently due to three sources of variance; perceiver, target, and family effects. A family/contextual effect
on informant reports of problem behavior has not been previously reported. 相似文献