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241.
Chengzhi Li Ph.D. Dong Ma Ph.D. Kaifei Deng B.Sc. Yijiu Chen M.Sc. Ping Huang Ph.D. Zhenyuan Wang Ph.D. 《Journal of forensic sciences》2017,62(5):1345-1350
Estimating the postmortem interval (PMI) is very important in the forensic sciences. Although many approaches have been used for estimating the PMI, accurate PMI calculations are still difficult. In this study, four Sprague Dawley (SD) rats were sacrificed by suffocation, and muscle samples were collected by dissection at various time intervals (0, 48, 96, and 144 h) after death. All samples were probed using matrix‐assisted laser desorption/ionization time‐of‐flight mass spectrometry (MALDI‐TOFMS) to obtain molecular images and data for principal component analysis (PCA). The results showed that the peaks at m/z 1511, 1543, 1564, 1586 clearly decreased in intensity from 0 to 144 h postmortem and that the time groups were separated from each other on the PCA score plot. The prediction model showed high recognition capability (95.93%) and cross‐validation (83.72%). Our work suggests that MALDI‐TOF MS can be used to determine the PMI. 相似文献
242.
James W. Rajotte M.Sc. Jean‐Paul F.P. Palmentier M.Sc. Helena Rachelle Wallage M.Sc. 《Journal of forensic sciences》2017,62(5):1410-1413
This case report details an individual arrested for drug‐impaired driving after leaving the scene of multiple motor vehicle collisions and evading police. The driver was examined by a drug recognition expert and failed the drug recognition evaluation. The driver admitted to using cocaine, marijuana, an antidepressant medication and “N‐bomb,” a novel psychoactive substance that possesses hallucinogenic properties. Toxicological analyses at the Centre of Forensic Sciences’ Toronto laboratory revealed only the substance 2‐[4‐chloro‐2,5‐dimethoxyphenyl]‐N‐[(2‐methoxyphenyl)methyl]ethanamine (25C‐NBOMe) in the accused's urine. This is the first report in which 25C‐NBOMe was identified through DRE and toxicological analyses in a drug‐impaired driver. 相似文献
243.
A Computational Framework for Age‐at‐Death Estimation from the Skeleton: Surface and Outline Analysis of 3D Laser Scans of the Adult Pubic Symphysis 下载免费PDF全文
Bridget F. B. Algee‐Hewitt Ph.D. Jieun Kim Ph.D. Dennis E. Slice Ph.D. 《Journal of forensic sciences》2017,62(6):1434-1444
In forensic anthropology, age‐at‐death estimation typically requires the macroscopic assessment of the skeletal indicator and its association with a phase or score. High subjectivity and error are the recognized disadvantages of this approach, creating a need for alternative tools that enable the objective and mathematically robust assessment of true chronological age. We describe, here, three fully computational, quantitative shape analysis methods and a combinatory approach that make use of three‐dimensional laser scans of the pubic symphysis. We report a novel age‐related shape measure, focusing on the changes observed in the ventral margin curvature, and refine two former methods, whose measures capture the flatness of the symphyseal surface. We show how we can decrease age‐estimation error and improve prior results by combining these outline and surface measures in two multivariate regression models. The presented models produce objective age‐estimates that are comparable to current practices with root‐mean‐square‐errors between 13.7 and 16.5 years. 相似文献
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246.
Predictors of Initial Court Agreement and 1‐Year Relitigation in Title IV‐D Contested Paternity Cases 下载免费PDF全文
Ani R. Poladian Brittany N. Rudd Amy Holtzworth‐Munroe Amy G. Applegate Brian M. D'Onofrio 《Family Court Review》2017,55(2):243-259
We examined potential predictors of initial court agreement and 1‐year relitigation in a sample of contested paternity cases involving unmarried parents coming to court to establish paternity, child support, and other issues. Cases participated in an RCT of a parent program and of a waiting period between establishment of paternity and court hearing. We controlled for RCT study factors and used baseline assessment data to predict likelihood of reaching full agreement in the initial court hearing and relitigation in the following year. Findings suggest that cases in which parents get along better outside of court are more likely to reach agreement and less likely to return to court. Additionally, particular parent demographics predict lower likelihood of reaching initial agreement (e.g., parents are non‐White, father earns below $10,000 yearly), more relitigation (e.g., parents are non‐White, mother earns above $10,000 yearly, father has children with others), and less relitigation (e.g., father earns above $10,000 yearly). Child demographics and most parent relationship characteristics did not predict outcomes. We discuss findings and offer suggestions for court interventions. 相似文献
247.
Adaptive and Maladaptive Gatekeeping Behaviors and Attitudes: Implications for Child Outcomes After Separation and Divorce 下载免费PDF全文
Gatekeeping has been used as a theory and a measure to describe and assess family dynamics within the context of separation and divorce. In this article, we explore adaptive and maladaptive gatekeeping behaviors and attitudes that can affect the other parent's relationship with the child. Implications are presented for connecting adaptive and maladaptive gatekeeping responses to child outcomes of safety, well‐being, and positive parent–child relationships following separation and divorce. We build on the recent attention to gatekeeping as a potential framework within the child custody context. 相似文献
248.
MARVIN D. KROHN JEFFREY T. WARD TERENCE P. THORNBERRY ALAN J. LIZOTTE REBEKAH CHU 《犯罪学》2011,49(4):991-1028
The short‐run deleterious effects of gang involvement during adolescence have been well researched. However, surprisingly little empirical attention has been devoted to understanding how gang involvement in adolescence influences life chances and criminal behavior in adulthood. Drawing on the life‐course perspective, this study argues that gang involvement will lead to precocious transitions that, in turn, will have adverse consequences on the fulfillment of adulthood roles and statuses in the economic and family spheres. Moreover, problems fulfilling these conventional roles are hypothesized then to lead to sustained involvement in criminal behavior in adulthood. Using data from a sample of males from the Rochester Youth Development Study, results from structural equation models support the indirect link between gang membership and noncriminal and criminal outcomes in adulthood. Specifically, gang involvement leads to an increase in the number of precocious transitions experienced that result in both economic hardship and family problems in adulthood. These failures in the economic and family realms, in turn, contribute to involvement in street crime and/or arrest in adulthood. Implications for the criminal desistance process are discussed. 相似文献
249.
Abstract: Use of immunochromatographic membranes for the detection of prostate‐specific antigen (PSA) has become commonplace in forensic laboratories. Experiments were designed to test the newly developed Seratec® SeraQuant? for accuracy, precision, and consistency in the quantitation of PSA. PSA standards were diluted with buffers and run on the instruments. Values obtained were examined for accuracy (was the correct value obtained?) and precision (were multiple sample values consistent?). To test for variation between instruments, large volumes of diluted PSA standard were run repeatedly on six units and the values obtained were plotted against the known PSA values to obtain a standard curve for each instrument. Fifty membranes having negative or weak positive results were then run on the six units, and the adjusted values were recorded and compared. Results of these experiments indicate that the instruments are accurate and precise in the quantitation of low levels of PSA. 相似文献
250.
Hughes CE Juarez CA Hughes TL Galloway A Fowler G Chacon S 《Journal of forensic sciences》2011,56(5):1094-1106
The nonmetric "trait list" methodology is widely used for estimating ancestry of skeletal remains. However, the effects of the method's embedded subjectivity on subsequent accuracy and consistency are largely unknown. We develop a mathematical simulation to test whether variation in the application of the "trait list" method alters the ancestry estimation for a given case. Our simulation explores how variations in (i) trait selection, (ii) number of traits employed, and (iii) ancestry choice thresholds affect the ancestry estimation of an unidentified skeleton. Using two temporally and geographically diverse samples, the simulation demonstrates that trait selection, trait quantity, threshold choices, and the exclusion of high-frequency traits had minimal effect on estimation of general ancestry. For all data sets and Runs, Accuracy(AS) was maintained above 90%. The authors close with a discussion on the logistical issues present when choosing traits, and how to avoid ancestry bias. 相似文献