Showing papers in "Journal of Forensic Sciences in 2015"

Letter to the Editor- Context Management Toolbox: A Linear Sequential Unmasking (LSU) Approach for Minimizing Cognitive Bias in Forensic Decision Making.

Abstract: J Forensic Sci, July 2015, Vol. 60, No. 4 doi: 10.1111/1556-4029.12805 Available online at: onlinelibrary.wiley.com Letter to the Editor— Context Management Toolbox: A Linear Sequential Unmasking (LSU) Approach for Minimizing Cognitive Bias in Forensic Decision Making Sir, The 2009 NAS report (1) criticized forensic scientists for making insufficient efforts to reduce their vulnerability to cogni- tive and contextual bias. Over the past few years, however, the field has begun to take steps to address this issue. There have been major workshops on cognitive bias, and the Organization of Scientific Area Committees (OSAC), 1 as well as the National Commission on Forensic Science, have created committees on Human Factors that are specifically charged with examining this issue. 2 A number of tools and methods for minimizing bias are under consideration. Some of these tools have already been imple- mented in a few forensic laboratories. In general, these tools are designed to protect and enhance the independence of mind of forensic examiners, particularly those who rely on subjective judgment to make their decisions. Several types of contextual information are of concern, as illus- trated in Fig. 1. We organize them into a taxonomy of five levels (based on a four-level taxonomy suggested by Stoel et al. [2]). The five-level taxonomy differentiates task-irrelevant information that may be conveyed to an analyst by the trace evidence itself (Level 1), the reference samples (Level 2), the case information (Level 3), examiners’ base rate expectations that arise from their experience (e.g., when the examiner expects a particular result— Level 4), and organizational and cultural factors (Level 5). A variety of tools are available for addressing cognitive bias. Different tools are useful for managing exposure to each level of task-irrelevant information. For example, case managers (3,4) is a straightforward tool for dealing with bias from case informa- tion (Level 3). In general, these procedures are designed to pre- vent contextual bias by protecting the examiner from exposure to task-irrelevant information. However, it is important to note that some types of information, while potentially biasing, may also be task relevant (5). These types of biasing information are more difficult to deal with. For example, in some instances, evidence that analysts must examine to perform their duties may contain information that is potentially biasing. This can pertain to cases in which Level 1 information, the trace evidence being evaluated, contains contextual informa- tion (e.g., blood spatter patterns that contain information about the nature of the crime, or handwriting and voice samples in which the meaning of the words is potentially biasing). Reference samples are another example of relevant material that is also potentially biasing (Level 2). These samples are clearly relevant because the analyst must compare them to trace evidence samples to determine whether they are similar enough to conclude that they come from the same source. But it is pos- sible that an analyst’s interpretation of the trace evidence might inadvertently be influenced by knowing the characteristics of the See: http://www.nist.gov/forensics/osac/hfc.cfm. The authors of this letter are comprised primarily from members of the OSAC Human Factors Committee, the Human Factors Subcommittee of the National Commission on Forensic Science, and authors of the original Sequential Unmasking. © 2015 American Academy of Forensic Sciences Fig. 1––A taxonomy of the different levels at which task-irrelevant and potentially biasing contextual information may reach a forensic scientist. reference samples—a form of bias arising from circular reason- ing. To manage this type of bias, one must look to other tools in the context management toolbox. The most widely discussed tool for this purpose is sequential unmasking (6). In contrast to other context management tools (3,5), the sequential unmasking approach does not prevent exposure to biasing relevant information. However, it does mandate that this information be presented as late as possible in the exami- nation process and only when it is necessary. A critical ele- ment of sequential unmasking is that the forensic examiner must first examine and document the trace evidence from the crime scene (Level 1), before being exposed to the known reference material (Level 2). This approach is linear in the sense that one must begin with the trace evidence before being exposed to and working with the reference material, thus working from the evidence to the sus- pect, rather than from the suspect to the evidence. The trace evi- dence should be interpreted the same in this initial step, regardless of any suspect who is considered as a possible (or even likely) source of the trace evidence. However, according to sequential unmasking (6), examiners are permitted to revisit, as well as change, their initial analysis of the trace evidence once they have reviewed the reference material, provided that they document these changes. Sequential unmasking allows unlimited and unrestricted changes to the evidence once exposed to the reference material. We believe it is important to impose limits and restrictions for when examiners are permitted to revisit and alter their initial analysis of trace evidence. The analysis of traces is most objec- tive when the examination is “context free”—that is, prior to exposure to the known reference samples. However, seeing the reference samples could alert the examiner to a possible over- sight, error, or misjudgment in the analysis of the trace evidence. Here, we seek to strike a balance between restrictive proce- dures that forbid analysts from changing their opinion and those that allow unlimited and unrestricted changes. The requirement that changes be documented does not eliminate the possibility that such changes arose from bias—it only makes that possibility more transparent.

Estimating Time Since Death from Postmortem Human Gut Microbial Communities

Abstract: Postmortem succession of human-associated microbial communities ("human microbiome") has been suggested as a possible method for estimating postmortem interval (PMI) for forensic analyses. Here we evaluate human gut bacterial populations to determine quantifiable, time-dependent changes postmortem. Gut microflora were repeatedly sampled from the proximal large intestine of 12 deceased human individuals as they decayed under environmental conditions. Three intestinal bacterial genera were quantified by quantitative PCR (qPCR) using group-specific primers targeting 16S rRNA genes. Bacteroides and Lactobacillus relative abundances declined exponentially with increasing PMI at rates of Nt=0.977e(-0.0144t) (r2=0.537, p<0.001) and Nt=0.019e(-0.0087t) (r2=0.396, p<0.001), respectively, where Nt is relative abundance at time (t) in cumulative degree hours. Bifidobacterium relative abundances did not change significantly: Nt=0.003e(-0.002t) (r2=0.033, p=0.284). Therefore, Bacteroides and Lactobacillus abundances could be used as quantitative indicators of PMI.

Potential Use of Bacterial Community Succession in Decaying Human Bone for Estimating Postmortem Interval

Abstract: Bacteria are taphonomic agents of human decomposition, potentially useful for estimating postmortem interval (PMI) in late-stage decomposition. Bone samples from 12 individuals and three soil samples were analyzed to assess the effects of decomposition and advancing time on bacterial communities. Results indicated that partially skeletonized remains maintained a presence of bacteria associated with the human gut, whereas bacterial composition of dry skeletal remains maintained a community profile similar to soil communities. Variation in the UniFrac distances was significantly greater between groups than within groups (p < 0.001) for the unweighted metric and not the weighted metric. The members of the bacterial communities were more similar within than between decomposition stages. The oligotrophic environment of bone relative to soft tissue and the physical protection of organic substrates may preclude bacterial blooms during the first years of skeletonization. Therefore, community membership (unweighted) may be better for estimating PMI from skeletonized remains than community structure (weighted).

The Potential of High‐throughput Metagenomic Sequencing of Aquatic Bacterial Communities to Estimate the Postmortem Submersion Interval

Abstract: Human remains can be discovered in freshwater or marine ecosystems, circumstances where insects and other invertebrates have infrequently been used for understanding the time of postmortem submersion. In this study, the identification and succession of epinecrotic bacterial communities on vertebrate remains were described during decomposition in a temperate headwater stream during two seasons (summer and winter). Bacterial communities were characterized with 454 pyrosequencing and analyzed at phyletic and generic taxonomic resolutions. There was a significant increase in genera richness over decomposition during both seasons. Additionally, multivariate statistical modeling revealed significant differences in bacterial communities between seasons at both taxonomic resolutions and siginificant genera differences among sampling days within each season, suggesting a succession of these communities. These data are the first to describe aquatic bacterial succession using high-throughput metagenomic sequencing on vertebrate remains submerged in a freshwater habitat, and provide initial evidence for their potential use in forensic investigations.

Determination of sex: interest of frontal sinus 3D reconstructions.

Abstract: Frontal sinuses (FSs) have been studied in radiology, anthropology, and forensic anthropology. This study aimed to determine whether it was possible to predict the age and sex of an individual using FS volume. Sixty-nine anonymized CT scans were imported to MIM-ICS 10.01r software (Materialise N.V.), and each FS volume was calculated in mm3. There was an absence of significant difference between right and left FS volume (p = 0.173) and an absence of correlation between age and FS volume (Pearson’s test; p = 0.705). Sexual dimorphism was significantly different (p = 0.001). However, the most discriminant datum for determining sex was found to be the total FS volume (sum of an individual’s right and left FS volumes) with linear discriminant Fisher’s function coefficients of -2.759 for the male group and -1.275 for the female group. With this model, 72.5% of our sample was correctly classified according to sex.

Taxonomy of Challenges for Digital Forensics.

Abstract: Since its inception, over a decade ago, the field of digital forensics has faced numerous challenges. Despite different researchers and digital forensic practitioners having studied and analysed various known digital forensic challenges, as of 2013, there still exists a need for a formal classification of these challenges. This article therefore reviews existing research literature and highlights the various challenges that digital forensics has faced for the last 10 years. In conducting this research study, however, it was difficult for the authors to review all the existing research literature in the digital forensic domain; hence, sampling and randomization techniques were employed to facilitate the review of the gathered literature. Taxonomy of the various challenges is subsequently proposed in this paper based on our review of the literature. The taxonomy classifies the large number of digital forensic challenges into four well-defined and easily understood categories. The proposed taxonomy can be useful, for example, in future developments of automated digital forensic tools by explicitly describing processes and procedures that focus on addressing specific challenges identified in this paper. However, it should also be noted that the purpose of this paper was not to propose any solutions to the individual challenges that digital forensics face, but to serve as a survey of the state of the art of the research area.

Forensic Entomology and the Estimation of the Minimum Time Since Death in Indoor Cases

Abstract: Eight cases that occurred indoors in which the insects played an important role in the mPMI estimation are presented. The bodies of socially isolated people and old people living alone were discovered in central Italy between June and November. mPMI ranged from a few days to several weeks. Insects were collected during the body recovery and the postmortem. Climatic data were obtained from the closest meteorological stations and from measurements performed on the site. Sarcophagidae and Calliphoridae species were present in 75% of the cases with Lucilia sericata and Chrysomya albiceps collected in 50% of the cases. Chrysomya albiceps was always found in association with Lucilia species. Scuttle flies (Phoridae) were found in 37.5% of the cases, confirming the ability of these species in indoor body colonization. We show that if sealed environment may delay, the insect arrival dirty houses may create the environment where sarcosaprophagous insects are already present.

Forensic Evidence in Homicide Investigations and Prosecutions

Abstract: Even though forensic evidence is collected at virtually every homicide scene, only a few studies have examined its role in investigation and prosecution. This article adds to the literature by providing the results of a study of 294 homicide cases (315 victims) occurring in Cleveland, Ohio, between 2008 and 2011. Through a logistic regression on open versus closed cases, the collection of knives, administration of gunshot residue (GSR) kits, and clothing at the scene were positively and significantly related to case closures, while collection of ballistics evidence and DNA evidence were statistically significant in the opposite direction. With regard to analysis, the clearance rate for cases with probative results (i.e., matches or exclusions) was 63.1% compared to a closure rate of 56.3% for cases without probative results. However, only 23 cases had probative results prior to arrest compared to 128 cases with probative results after arrest.

The Impact of Daubert on the Admissibility of Forensic Anthropology Expert Testimony

Abstract: Forensic anthropologists anticipated a significant impact from the 1993 Supreme Court Daubert decision, which addressed the standard of admissibility for expert testimony. In response, many forensic articles cited Daubert in the search for objective techniques or a critique of established subjective methods. This study examines challenges to forensic anthropological expert testimony to evaluate whether Daubert has actually affected the admissibility of such testimony. Thirty cases were identified that addressed the admissibility of the testimony, including 14 cases prior to Daubert and 16 after Daubert. Examination of these cases indicates that post-Daubert cases do not result in more exclusions. Yet, this lack of exclusions may instead be viewed as a manifestation of the field's overall surge toward more objective and quantifiable techniques in a self-regulating response to Daubert.

Identification of different forms of cocaine and substances used in adulteration using near-infrared Raman spectroscopy and infrared absorption spectroscopy.

Abstract: Identification of cocaine and subsequent quantification immediately after seizure are problems for the police in developing countries such as Brazil. This work proposes a comparison between the Raman and FT-IR techniques as methods to identify cocaine, the adulterants used to increase volume, and possible degradation products in samples seized by the police. Near-infrared Raman spectra (785 nm excitation, 10 sec exposure time) and FT-IR-ATR spectra were obtained from different samples of street cocaine and some substances commonly used as adulterants. Freebase powder, hydrochloride powder, and crack rock can be distinguished by both Raman and FT-IR spectroscopies, revealing differences in their chemical structure. Most of the samples showed characteristic peaks of degradation products such as benzoylecgonine and benzoic acid, and some presented evidence of adulteration with aluminum sulfate and sodium carbonate. Raman spectroscopy is better than FT-IR for identifying benzoic acid and inorganic adulterants in cocaine.

Suicidal or homicidal sharp force injuries? A review and critical analysis of the heterogeneity in the forensic literature

Abstract: The differential diagnosis between self-inflicted and nonself-inflicted, suicidal and homicidal, injuries is difficult or impossible in many cases and, above all, cannot be made on the basis of information obtained solely from the autopsy or the medicolegal clinical examination. The purpose of this study is to analyze the literature on suicidal and homicidal sharp force injuries and identify the relevant parameters that may help differentiate between suicidal and homicidal deaths. To achieve this goal, a review of 595 potentially relevant articles was performed. After excluding the nonrelevant papers by screening the titles, all abstracts were reviewed, and articles meeting the inclusion criteria underwent a full-text review. The following parameters were compiled into a table: number of cases, localization of the injuries, and number of injuries. The data were statistically analyzed and compared with those available in the forensic literature. On the basis of the heterogeneity of data revealed by the present review, a simple and short checklist of the parameters that should be included when reporting suicides and homicides by sharp force has been proposed.

Fat Transfer and Fatal Macroembolization

Abstract: Fat embolism is usually associated with long bone fractures or other trauma. The diagnosis is usually clinical, and in most cases, emboli are not fatal and not usually seen on gross examination. At the Los Angeles County Coroner's Office, we autopsied the victim of fatal macroscopic fat embolization to the lungs. The patient died during buttock enhancement surgery when fat from liposuction was injected into her buttocks. Fat embolism from liposuction and fat injection is reportedly rare, and macroscopic embolization is rarer still. Varicose veins can occur in the area of the sciatic notch and are known to cause painful sciatica symptoms. We suggest them as a potential conduit for macroscopic fat to reach the lungs. Simple pre-operative questioning for sciatica symptoms and possible radiologic study to rule out sciatic varices seem prudent before undertaking buttock-enhancing surgery. Careful fat injection with pre-aspiration is always advised.

Direct PCR Improves the Recovery of DNA from Various Substrates.

Abstract: This study reports on the comparison of a standard extraction process with the direct PCR approach of processing low-level DNA swabs typical in forensic investigations. Varying concentrations of control DNA were deposited onto three commonly encountered substrates, brass, plastic, and glass, left to dry, and swabbed using premoistened DNA-free nylon FLOQswabs(™) . Swabs (n = 90) were either processed using the DNA IQ(™) kit or, for direct PCR, swab fibers (~2 mm(2) ) were added directly to the PCR with no prior extraction. A significant increase in the height of the alleles (p < 0.005) was observed when using the direct PCR approach over the extraction methodology when controlling for surface type and mass of DNA deposited. The findings indicate the potential use of direct PCR for increasing the PCR product obtained from low-template DNA samples in addition to minimizing contamination and saving resources.

An investigation of red fox (Vulpes vulpes) and Eurasian badger (Meles meles) scavenging, scattering, and removal of deer remains: forensic implications and applications

Abstract: Within northwest Europe, especially the United Kingdom, the red fox (Vulpes vulpes) and the Eurasian Badger (Meles meles) are the largest wild scavengers capable of modifying a set of remains through scavenging. Knowledge of region-specific and species-typical scavenging behaviors of scavengers within the crime scene area and surroundings can aid in more efficient and accurate interpretations. The scavenging behaviors of captive and wild foxes and badgers were recorded and compared through actualistic methods and direct observation. The scavenging by wild foxes and badgers of surface-deposited baits and whole deer (Cervus nippon; Capreolus capreolus) in a woodland was observed and analyzed. Wild foxes were found to scavenge deer more frequently than badgers. The scavenging of deer remains by foxes was also compared with forensic cases. The scavenging pattern and recovery distances of deer and human remains scavenged by foxes were similar but were potentially affected by the condition and deposition of a body, and the presence of clothing.

Modeling Bone Surface Morphology: A Fully Quantitative Method for Age-at-Death Estimation Using the Pubic Symphysis.

Abstract: The pubic symphysis is widely used in age estimation for the adult skeleton. Standard practice requires the visual comparison of surface morphology against criteria representing predefined phases and the estimation of case-specific age from an age range associated with the chosen phase. Known problems of method and observer error necessitate alternative tools to quantify age-related change in pubic morphology. This paper presents an objective, fully quantitative method for estimating age-at-death from the skeleton, which exploits a variance-based score of surface complexity computed from vertices obtained from a scanner sampling the pubic symphysis. For laser scans from 41 modern American male skeletons, this method produces results that are significantly associated with known age-at-death (RMSE = 17.15 years). Chronological age is predicted, therefore, equally well, if not, better, with this robust, objective, and fully quantitative method than with prevailing phase-aging systems. This method contributes to forensic casework by responding to medico-legal expectations for evidence standards.

Fatal intoxication with methoxetamine.

Abstract: Methoxetamine (MXE) is a new synthetic drug of abuse structurally related to ketamine and phencyclidine. A case of a 29-year-old male with acute toxicity related to the analytically confirmed use of MXE is reported. The man was found dead at his residence. Biological material was analyzed using liquid chromatography-tandem mass spectrometry. The concentration of MXE in urine of the deceased was 85 μg/mL. Despite the vial containing the blood sample being destroyed during transportation and the blood leaking out into the cardboard packaging, the blood level of MXE was estimated. After determination of the cardboard grammage (approx. 400 g/m(3) ) and the mean mass of the blood obtained after drying (0.1785 ± 0.0173 g per 1 mL), the estimated blood concentration of MXE was found to be 5.8 μg/mL. The high concentration of MXE in blood and urine and the circumstances of the case indicate an unintentional, fatal intoxication with this substance.

Age estimation in forensic anthropology: quantification of observer error in phase versus component-based methods.

Abstract: The purpose of this study was to assess observer error in phase versus component-based scoring systems used to develop age estimation methods in forensic anthropology. A method preferred by forensic anthropologists in the AAFS was selected for this evaluation (the Suchey–Brooks method for the pubic symphysis). The Suchey–Brooks descriptions were used to develop a corresponding component-based scoring system for comparison. Several commonly used reliability statistics (kappa, weighted kappa, and the intraclass correlation coefficient) were calculated to assess observer agreement between two observers and to evaluate the efficacy of each of these statistics for this study. The linear weighted kappa was determined to be the most suitable measure of observer agreement. The results show that a component-based system offers the possibility for more objective scoring than a phase system as long as the coding possibilities for each trait do not exceed three states of expression, each with as little overlap as possible.

Development of Latent Fingermarks on Various Surfaces Using ZnO‐SiO2 Nanopowder

Abstract: Fingermarks are one of the most useful forms of evidence in identification and can provide generalized proof of identity in crime investigation. They are developed using various conventional powders. The novel nanopowder ZnO-SiO2 was synthesized via the conventional heating method and characterized by Fourier transform infrared spectroscopy (FTIR), scanning electron microscope (SEM), energy-dispersive X-ray (EDX) analysis, transmission electron microscope (TEM), and X-ray diffraction (XRD). The mean particle size of ZnO-SiO2 nanopowder calculated through TEM was 32.9 nm. The development of fingermarks was carried out by powder dusting and small particle reagent (SPR) methods. Powder dusting method was used for the development of latent fingermarks on various dry, nonporous, and semi-porous surfaces. The SPR method was also applied to wet nonporous surface. The developed latent fingermarks using ZnO-SiO2 nanopowder were found to have excellent quality with very clear third-level ridges detail and had better visibility than commercially available white powder.

Morphological Assessment of Ancestry using Cranial Macromorphoscopics

Abstract: Ancestry estimation is essential for biological profile estimation in forensic anthropology. Hefner (2009) and Osteoware (Smithsonian Institution, 2011) presented 16 macromorphoscopic traits that can be scored for standardized data collection and can also be used within a statistical framework to estimate ancestry. The primary purpose of this research was to examine the utility of these traits for assessing ancestry. Tests of observer agreement and the range of variation in trait expression were evaluated. A sample of 208 American whites and blacks from the Hamann-Todd Collection were scored, and several classification methods were utilized in accordance with Hefner (2009). Correct classifications for the pooled sex analyses ranged from 73.3% to 86.6% and from 46.7% to 64.3% when the sexes were analyzed independently. Interobserver agreement was variable and was found to be lower than that presented in Hefner (2009). Trait expression was variable in both groups and was generally consistent with Hefner's findings.

The variability of ecstasy tablets composition in Brazil.

Abstract: The content of ecstasy tablets has been changing over the years, and nowadays 3,4-methylenedioxymethamphetamine (MDMA) is not always present in the tablets The aim of this study was to investigate the chemical composition in the seized tablets labeled as ecstasy We analyzed samples from 150 different seizures made by Sao Paulo's State Police by gas chromatography-mass spectrometry MDMA was present in 447% of the analyzed samples, and another twenty different active substances were identified in these tablets, such as caffeine, 2C-B, piperazines, amphetamines, phencyclidine, and others Methamphetamine was present in 22% of these samples The results demonstrate a huge shift in the pattern of trafficking of synthetic drugs, where MDMA has been replaced in tablets mostly by illicit psychoactive substances, in a clear attempt to bypass the law The great variability in the tablets composition may lead to an increased risk of drug poisoning

Quantitative Analysis of the Morphological Changes of the Pubic Symphyseal Face and the Auricular Surface and Implications for Age at Death Estimation

Abstract: Age estimation methods are often based on the age-related morphological changes of the auricular surface and the pubic bone. In this study, a mathematical approach to quantify these changes has been tested analyzing the curvature variation on 3D models from CT and laser scans. The sample consisted of the 24 Suchey–Brooks (SB) pubic bone casts, 19 auricular surfaces from the Buckberry and Chamberlain (BC) “recording kit” and 98 pelvic bones from the Terry Collection (Smithsonian Institution). Strong and moderate correlations between phases and curvature were found in SB casts (q 0.60–0.93) and BC “recording kit” (q 0.47–0.75), moderate and weak correlations in the Terry Collection bones (pubic bones: q 0.29–0.51, auricular surfaces: q 0.33– 0.50) but associated with large individual variability and overlap of curvature values between adjacent decades. The new procedure, requiring no expert judgment from the operator, achieved similar correlations that can be found in the classic methods.

A Comprehensive and Harmonized Digital Forensic Investigation Process Model.

Abstract: Performing a digital forensic investigation (DFI) requires a standardized and formalized process. There is currently neither an international standard nor does a global, harmonized DFI process (DFIP) exist. The authors studied existing state-of-the-art DFIP models and concluded that there are significant disparities pertaining to the number of processes, the scope, the hierarchical levels, and concepts applied. This paper proposes a comprehensive model that harmonizes existing models. An effort was made to incorporate all types of processes proposed by the existing models, including those aimed at achieving digital forensic readiness. The authors introduce a novel class of processes called concurrent processes. This is a novel contribution that should, together with the rest of the model, enable more efficient and effective DFI, while ensuring admissibility of digital evidence. Ultimately, the proposed model is intended to be used for different types of DFI and should lead to standardization.

DNA in the criminal justice system: the DNA success story in perspective

Abstract: Current figures on the efficiency of DNA as an investigative tool in criminal investigations only tell part of the story. To get the DNA success story in the right perspective, we examined all forensic reports from serious (N = 116) and high-volume crime cases (N = 2791) over the year 2011 from one police region in the Netherlands. These data show that 38% of analyzed serious crime traces (N = 384) and 17% of analyzed high-volume crime traces (N = 386) did not result in a DNA profile. Turnaround times (from crime scene to DNA report) were 66 days for traces from serious crimes and 44 days for traces from high-volume crimes. Suspects were truly identified through a match with the Offender DNA database of the Netherlands in 3% of the serious crime cases and in 1% of the high-volume crime cases. These data are important for both the forensic laboratory and the professionals in the criminal justice system to further optimize forensic DNA testing as an investigative tool.

Child sexual abuse in Turkey: an analysis of 1002 cases

Abstract: This study investigated the characteristics of abuse suffered by children, the dimensions of the psychiatric effects associated with abuse, and the factors affecting these. One thousand two cases aged under 18, exposed to sexual abuse, and referred over a 7-year period were assessed. Girls represented 80.8% of cases, and the numbers rose with age. The aggressors were all male, and 88.2% were known to their victim. Approximately half the children were exposed to sexual abuse involving penetration. Psychological pathology was identified in 62.1%. Female gender, the presence of penetration, physical violence, and incest significantly increased the development of psychological pathology. Levels of awareness in people close to and trusted by the child must be raised to minimize the adverse effects of trauma in the long term, preventive measures must be taken, and medical and social support units from which victims can receive assistance need to be established.

Postcranial sex estimation criteria for Mexican Hispanics

Abstract: Population-specific reference data are necessary for sex estimation in forensic anthropological practice. Currently, there are no population-specific data for Hispanics equivalent to data available for American Blacks and Whites. Individuals of Mexican origin represent the largest group of Hispanics in the United States (Spradley and Jantz. 2011. J Forensic Sci;56:289). This paper presents new population-specific sex estimation criteria for postcranial measurements for Mexican Hispanics. Metric data come from positively identified border-crossing fatalities at the Pima County Office of the Medical Examiner and documented cemetery collections curated at Universidad Nacional Autonoma de Mexico and Universidad Autonoma de Yucatan. Stepwise variable selection procedures and discriminant function analyses were utilized to generate classification functions for postcrania. Sectioning points were also created for select measurements. Both the cross-validated classification rates and sectioning points achieved accuracy rates as high as 95% and 92%, respectively. These new criteria will improve sex estimation for US Mexico border crossers and Hispanics in the US.

Sex Determination by Discriminant Function Analysis of Lumbar Vertebrae

Abstract: Sex determination is critical for developing the biological profile of unidentified skeletal remains. When more commonly used elements (os coxa, cranium) for sexing are not available, methods utilizing other skeletal elements are needed. This study aims to assess the degree of sexual dimorphism of the lumbar vertebrae and develop discriminant functions for sex determination from them, using a sample of South African blacks from the Raymond A. Dart Collection (47 males, 51 females). Eleven variables at each lumbar level were subjected to univariate and multivariate discriminant function analyses. Univariate equations produced classification rates ranging from 57.7% to 83.5%, with the highest accuracies associated with dimensions of the vertebral body. Multivariate stepwise analysis generated classification rates ranging from 75.9% to 88.7%. These results are comparable to other methods for sexing the skeleton and indicate that measures of the lumbar vertebrae can be used as an effective tool for sex determination.

The Homicide-Suicide Phenomenon: Findings of Psychological Autopsies.

Abstract: Homicide-suicide represents a single episode of violence which may decimate an entire family. This study aimed to further describe motives and context of these tragedies. Psychological autopsies were completed for 18 homicide-suicide cases in Dallas, Texas. This included postevent interviews with surviving family members and review of police and coroner records. Two-thirds of perpetrators had made either verbal or written threats prior to the homicide-suicide. A simplified typology describing victim-perpetrator relationship and motive type is suggested for future studies and clinical ease. Two-thirds of perpetrators fell into the category of Intimate-Possessive, most of whom were depressed men who were abusing substances and undergoing separation. Additional categories included Intimate-Ailing, Filial-Revenge, Familial-Psychotic, and Friend-Psychotic. Further, implications from this psychological autopsy study regarding risk assessment include use of collateral interviews regarding threats and past violence.

Symptom Checklist-90-Revised Scores in Adult Children Exposed to Alienating Behaviors: An Italian Sample

Abstract: This study addresses a particular form of child psychological maltreatment, exposing a child to alienating behaviors in the context of a high degree of conflict between the parents. The objective of this research was to identify retrospectively the alienating behaviors that occurred in an Italian sample of children and the reported associated psychosocial symptoms. Seven hundred and thirty-nine adults in Chieti, Italy, completed an anonymous and confidential survey regarding their childhood exposure to parental alienating behaviors and measures of current symptomatology. About 75% of the sample reported some exposure to parental alienating behaviors; 15% of the sample endorsed the item, "tried to turn me against the other parent." The results revealed strong and statistically significant associations between reported exposure to parental alienating behaviors and reports of current symptomatology. Language: en

Volatile emission of decomposing pig carcasses (Sus scrofa domesticus L.) as an indicator for the postmortem interval.

Abstract: This study aimed at correlating selected carcass borne volatile organic compounds (VOCs) with the postmortem interval (PMI). Selected volatiles should 1st be reliably emitted during vertebrate decay, 2nd be emitted at high concentrations, and 3rd show a reproducible quantitative dynamic during the decaying process. Four pigs (Sus scrofa domesticus L.) were placed in a deciduous forest in different seasons and volatiles emitted during the decaying process were sampled. Seventeen compounds were identified and quantified by GC-MS. Electrophysiological experiments on the antenna of female Calliphora vicina and additional data of Dermestes maculans were used as an evolutionary tuned information filter to evaluate the 1st criterion. The relative quantitative emission of hexanal, nonanal, dimethyl disulfide, dimethyl trisulfide, 1-butanol, and phenol were correlated with the PMI, and the observed stages of decay and the limitations of this model were discussed.

Determination of herbicides paraquat, glyphosate, and aminomethylphosphonic acid in marijuana samples by capillary electrophoresis.

Abstract: In this work, two methods were developed to determine herbicides paraquat, glyphosate, and aminomethylphosphonic acid (AMPA) in marijuana samples by capillary electrophoresis. For paraquat analysis, sample was extracted with aqueous acetic acid solution and analyzed by capillary zone electrophoresis with direct UV detection. The running electrolyte was 50 mmol/L phosphate buffer (pH 2.50). For glyphosate and AMPA, indirect UV/VIS detection was used, as these substances do not present chromophoric groups. Samples were extracted with 5 mmol/L hydrochloric acid. The running electrolyte was 10 mmol/L gallic acid, 6 mmol/L TRIS, and 0.1 mmol/L CTAB (pH = 4.7). The methods presented good linearity, precision, accuracy, and recovery. Paraquat was detected in 12 samples (n = 130), ranging from 0.01 to 25.1 mg/g. Three samples were positive for glyphosate (0.15-0.75 mg/g), and one sample presented AMPA as well. Experimental studies are suggested to evaluate the risks of these concentrations to marijuana user.