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991.
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
992.
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literature regarding the upkeep of dermestid colonies for skeletal remains processing either lack specificity or are outdated.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
993.
Abu-Rus Ana Thompson Kenneth J. Naish Brandi L. Brown Cassie Dalenberg Constance 《Psychological injury and law》2020,13(2):167-177
Psychological Injury and Law - The Dissociative Experiences Scale (DES), the most commonly used scale for assessing dissociation across settings, lacks a validity scale. In this study, six methods... 相似文献
994.
Paolo Roma Luciano Giromini Franco Burla Stefano Ferracuti Donald J. Viglione Cristina Mazza 《Psychological injury and law》2020,13(1):57-65
The Inventory of Problems-29 (IOP-29; Viglione, Giromini, & Landis, Journal of Personality Assessment, 99(5), 534–544, 2017) is a 29-item, recently published, self-administered test aimed at assessing the credibility of various symptom presentations. Although available research strongly supports the use of this symptom validity test in malingering-related contexts, to date, only few studies have analyzed data from real-life forensic evaluations. To fill this gap and explore ecological and convergent validity, the current study analyzed data from 74 court-ordered evaluations aimed at establishing the possible presence of psychological injury. Such evaluations are high-stakes situations in which exaggeration or malingering occur relatively often. We used a research-supported and popular symptom validity test, i.e., the Structured Inventory of Malingered Symptomatology (SIMS; Smith & Burger, Journal of the American Academy on Psychiatry and Law, 25:180–183, 1997), as our criterion variable. The IOP-29 produced excellent area under the curve (AUC) values of .98 with a recommended SIMS total score cutoff (≥ 17) and .99 when eliminating too-close-to-classify cases (Rogers & Bender, 2018) and very large Cohen’s d effect sizes of 2.98 and 3.59, respectively. Crucially, when implementing established cut scores from previous research, the IOP-29 yielded very high specificity and sensitivity rates, and the predictions from the two tests were strikingly similar. Taken together, these findings support the strong convergent validity of the IOP-29 and its utility in applied clinical and forensic settings. 相似文献
995.
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
996.
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: |
997.
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
998.
Roger J. R. Levesque 《Journal of youth and adolescence》2009,38(10):1281-1281
999.
Self-determination theory emphasizes the importance of school-based autonomy and belongingness to academic achievement and psychological adjustment,
and the theory posits a model in which engagement in school mediates the influence of autonomy and belongingness on these
outcomes. To date, this model has only been evaluated on academic outcomes. Utilizing short-term longitudinal data (5-month
timeframe) from a set of secondary schools in the rural Midwest (N = 283, M age = 15.3, 51.9% male, 86.2% White), we extend the model to include a measure of positive adjustment (i.e., hope). We also
find a direct link between peer-related belongingness (i.e., peer support) and positive adjustment that is not mediated by
engagement in school. A reciprocal relationship between academic autonomy, teacher-related belongingness (i.e., teacher support)
and engagement in learning is supported, but this reciprocal relationship does not extend to peer-related belongingness. The
implications of these findings for secondary schools are discussed.
相似文献
Mark J. Van RyzinEmail: |
1000.
Jennifer E. Lansford Ley A. Killeya-Jones Shari Miller Philip R. Costanzo 《Journal of youth and adolescence》2009,38(8):1084-1095
Sociometric nominations, social cognitive maps, and self-report questionnaires were completed in consecutive years by 327
students (56% girls) followed longitudinally from grade 7 to grade 8 to examine the stability of social standing in peer groups
and correlates of changes in social standing. Social preference, perceived popularity, network centrality, and leadership
were moderately stable from grade 7 to grade 8. Alcohol use and relational aggression in grade 7 predicted changes in social
preference and centrality, respectively, between grade 7 and grade 8, but these effects were moderated by gender and ethnicity.
Changes in social standing from grade 7 to grade 8 were unrelated to grade 8 physical aggression, relational aggression, and
alcohol use after controlling for the grade 7 corollaries of these behaviors. Results are discussed in terms of their implications
for understanding links between social standing and problem behaviors during adolescence.
相似文献
Jennifer E. LansfordEmail: |