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1.
Soil samples have potential to be useful in forensic investigations, but their utility may be limited due to the inherent variability of soil properties, the wide array of analytical methods, and complexity of data analysis. This study examined the differentiation of similar soils based on both gross (texture, color, mineralogy) and explicit soil properties (elemental composition, cation exchange, Fe‐oxyhydroxides). Soils were collected from Fallbrook and adjacent map units from Riverside and San Diego Counties in California. Samples were characterized using multiple techniques, including chemical extracts, X‐ray diffraction (XRD), and Fourier transform infrared spectroscopy. Results were analyzed using multiple analytical approaches to compare counties and land uses. Some analyses (XRD, extractions) were better at distinguishing among samples than others (color, texture). Ratios of rare earth elements were particularly useful for distinguishing samples between counties. This potential to “fingerprint” soils illustrates the usefulness of a comprehensive soil database for criminal investigators.  相似文献   

2.
Abstract: Current profiling of rough diamond source is performed using different physical and/or morphological techniques that require strong knowledge and experience in the field. More recently, chemical impurities have been used to discriminate diamond source and with the advance of laser ablation–inductively coupled plasma–mass spectrometry (LA‐ICP‐MS) empirical profiling of rough diamonds is possible to some extent. In this study, we present a LA‐ICP‐MS methodology that we developed for analyzing ultra‐trace element impurities in rough diamond for origin determination (“profiling”). Diamonds from two sources were analyzed by LA‐ICP‐MS and were statistically classified by accepted methods. For the two diamond populations analyzed in this study, binomial logistic regression produced a better overall correct classification than linear discriminant analysis. The results suggest that an anticipated matrix match reference material would improve the robustness of our methodology for forensic applications.  相似文献   

3.
Abstract: An LC–MS method was developed for benzylpiperazine (BZP) and trifluoromethylphenylpiperazine (TFMPP), constituents of “party pills” or “legal herbal highs,” and their metabolites in human blood plasma. Compounds were resolved using a mixture of ammonium formate (pH 4.5, 0.01 M) and acetonitrile (flow rate of 1.0 mL/min) with a C18 column. Calibration curves were linear from 1 to 50 ng/mL (R2 > 0.99); the lower limit of quantification (LLOQ) was 5 ng/mL; the accuracy was >90%; the intra‐ and interday relative standard deviations (R.S.D) were <5% and <10%, respectively. Human plasma concentrations of TFMPP were measured in blood samples taken from healthy adults (n = 6) over 24 h following a 60‐mg oral dose of TFMPP: these peaked at 24.10 ng/mL (±1.8 ng/mL) (Cmax) after 90 min (Tmax). Plasma concentrations of 1‐(3‐trifluoromethyl‐4‐hydroxyphenyl) piperazine peaked at 20.2 ng/mL (±4.6 ng/mL) after 90 min. TFMPP had two disposition phases (t½ = 2.04 h (±0.19 h) and 5.95 h (±1.63 h). Apparent clearance (Cl/F) was 384 L/h (±45 L/h).  相似文献   

4.
Jet‐propelled personal watercraft (PWC) or jet‐skis have become increasingly popular. The means of propulsion of PWC, which is a jet of water forced out of small nozzle at the rear of the craft, combined with a high risk of falling off of the seat and into close proximity with the water jet stream, raise the potential for a unique type of injury mechanism. The most serious injuries associated with PWC falls are those that occur when the perineum passes in close proximity to the jet nozzle and the high‐pressure water stream enters the vaginal or rectal orifice. We describe the forensic investigation into a case of an anovaginal “blowout” injury in a passenger who was ejected from the rear seat position of a PWC and subsequently suffered life‐threatening injuries to the pelvic organs. The investigation included a biomechanical analysis of the injury mechanism, a summary of prior published reports of internal pelvic injuries resulting from PWC falls as well as other water sports and activities, and a comparison of the severity of the injuries resulting from differing mechanisms using the New Injury Severity Score (NISS). The mean (±standard deviation [SD]) NISS values for reported PWC injuries [not including the NISS of 38 in this case study] were 11.2 (±9.5), while the mean value for reported water‐skiing falls was half that of the PWC group at 5.6 (±5.2). It was concluded that the analyzed injuries were unique to a PWC ejection versus other previously described non‐PWC‐associated water sport injuries. It is recommended that PWC manufacturers help consumers understand the potential risks to passengers with highly visible warnings and reduce injury risk with revised seat design, and/or passenger seat “deadman” switches.  相似文献   

5.
Abstract: This study provides forensic search teams with systematic geophysical monitoring data over simulated clandestine graves for comparison to active cases. Simulated “wrapped” and “naked” burials were created. Multigeophysical surveys were collected over a 3‐year monitoring period. Bulk ground resistivity, electrical resistivity imaging, multifrequency ground‐penetrating radar (GPR), and grave and background “soil‐water” conductivity data were collected. Resistivity surveys revealed the naked burial had consistently low‐resistivity anomalies, whereas the wrapped burial had small, varying high‐resistivity anomalies. GPR 110‐ to 900‐MHz frequency surveys showed the wrapped burial could be detected throughout, with the “naked” burial mostly resolved. Two hundred and twenty‐five megahertz frequency GPR data were optimal. “Soil‐water” analyses showed rapidly increasing (year 1), slowly increasing (year 2), and decreasing (year 3) conductivity values. Results suggest resistivity and GPR surveys should be collected if target “wrapping” is unknown, with winter to spring surveys optimal. Resistivity surveys should be collected in clay‐rich soils.  相似文献   

6.
This article provides a demographic exposition of the changes in the U.S prison population during the period of mass incarceration that began in the late twentieth century. By drawing on data from the Survey of Inmates in State Correctional Facilities (1974–2004) for inmates 17–72 years of age (N = 336), we show that the age distribution shifted upward dramatically: Only 16 percent of the state prison population was 40 years old or older in 1974; by 2004, this percentage had doubled to 33 percent with the median age of prisoners rising from 27 to 34 years old. By using an estimable function approach, we find that the change in the age distribution of the prison population is primarily a cohort effect that is driven by the “enhanced” penal careers of the cohorts who hit young adulthood—the prime age of both crime and incarceration—when substance use was at its peak. Period‐specific factors (e.g., proclivity for punishment and incidence of offense) do matter, but they seem to play out more across the life cycles of persons most affected in young adulthood (cohort effects) than across all age groups at one point in time (period effects).  相似文献   

7.
This ongoing monitoring study provides forensic search teams with systematic geophysical data over simulated clandestine graves for comparison to active cases. Simulated “wrapped,” “naked,” and “control” burials were created. Multiple geophysical surveys were collected over 6 years, here showing data from 4 to 6 years after burial. Electrical resistivity (twin electrode and ERI), multifrequency GPR, grave and background soil water were collected. Resistivity surveys revealed that the naked burial had low‐resistivity anomalies up to year four but then difficult to image, whereas the wrapped burial had consistent large high‐resistivity anomalies. GPR 110‐ to 900‐MHz frequency surveys showed that the wrapped burial could be detected throughout, but the naked burial was either not detectable or poorly resolved. 225‐MHz frequency GPR data were optimal. Soil water analyses showed decreasing (years 4 to 5) to background (year 6) conductivity values. Results suggest both resistivity and GPR surveying if burial style unknown, with winter to spring surveys optimal and increasingly important as time increases.  相似文献   

8.
Aluminum (Al) powders are commonly used in improvised explosive devices as metallic fuels, a component of explosive mixtures. These powders can be obtained readily from industrial‐scale and consumer products, and produced using unsophisticated “kitchen chemistry” techniques. This research demonstrates the potential of automated particle micromorphometry for comparisons between known source and questioned Al powders recovered from IEDs, as well as for insight into the method of Al powder manufacture. Al powder samples were obtained from legitimate manufacturers, and 56 samples were produced “in‐house” from Al‐containing spray paints and ball‐milled Al foils. Transmitted light microscope images of Al powder particles were acquired using an automated stage with automated z‐focus; 17 size and shape parameters were measured for all particles. Approximately 37,000–2,500,000 particles/sample were analyzed using an open‐source statistical package with customized code. Dimensionality reduction was required for processing the large datasets: eight of the 17 measured variables were selected based on inspection of the correlation matrix. Data from four subsamples from each of the 56 samples produced using “in‐house” methods were analyzed using ANOVA to assess the within‐ and between‐sample variation. High within‐sample variation was noted; however, ANOVA and post‐hoc Tukey's honestly significant difference (HSD) tests demonstrated that the between‐sample variation was substantially larger than the within‐sample variation. Each sample could be differentiated from all other samples in the test set. Future experiments will focus on ways to reduce the within‐sample variation, and additional statistical and microanalytical methods to classify sources and confidently constrain the method of Al powder manufacture.  相似文献   

9.
This paper argues that the writings of Hans Kelsen deserve more attention from those engaged in the debate on secularization and political theology. His lifelong struggle with various forms of legal‐political metaphysics is an identifiable thread in many of his writings. Kelsen’s concern with the theological‐political issues found in the theory of the state (Staatslehre) is far from being marginal. Kelsen claims that his theory aims at resolving the traditional dualism of law and state prevailing in the Staatslehre and contributes  to an “uncompromising destruction of one of the most effective ideologies of legitimacy.” Kelsen maintains that the contents of this “ideology of legitimacy” derive from both political metaphysics and the deep‐seated ancient ways of thinking on nature and society. In order to illustrate this thesis, I propose calling this phenomenon “totemism of the modern state.”  相似文献   

10.
Soil can play an important role in forensic cases in linking suspects or objects to a crime scene by comparing samples from the crime scene with samples derived from items. This study uses an adapted ED‐XRF analysis (sieving instead of grinding to prevent destruction of microfossils) to produce elemental composition data of 20 elements. Different data processing techniques and statistical distances were evaluated using data from 50 samples and the log‐LR cost (Cllr). The best performing combination, Canberra distance, relative data, and square root values, is used to construct a discriminative model. Examples of the spatial resolution of the method in crime scenes are shown for three locations, and sampling strategy is discussed. Twelve test cases were analyzed, and results showed that the method is applicable. The study shows how the combination of an analysis technique, a database, and a discriminative model can be used to compare multiple soil samples quickly.  相似文献   

11.
Nicolau syndrome (NS) is a dermatological adverse reaction of intramuscular injections and is caused by several mechanisms. The etiopathogenesis remains unclear, and several hypotheses have suggested a vascular origin. Rhabdomyolysis (RM) is the destruction of striated muscle, with the subsequent release of muscle cell contents into circulation. NS and RM diagnoses may overlap. Herein, we present the autopsy findings of a 40‐year‐old female with NS complicated with RM. On clinical follow‐up, creatine kinase (CK) was 7146 IU/L, and urea and creatinine levels were elevated on the third day after intramuscular diclofenac injection. Possible ischemic process triggered the RM and subsequent acute renal failure. The opportunity for an early diagnosis was missed because the patient delayed seeking medical aid. The prognosis worsened, and the patient died due to secondary sepsis. Early diagnosis of NS before the occurrence of complications is the most important issue in patient education and can be life‐saving.  相似文献   

12.
CP 47,497, a potent cannabinoid receptor type 1 agonist, is the main active ingredient in the herbal mixture “Spice” sold in European countries. The illegal use of “Spice” for its psychoactive effects has become a social issue. In this study, the in vitro metabolism of CP 47,497 was investigated in human liver microsomes to characterize the metabolic fate of CP 47,497. CP 47,497 was incubated with human liver microsomes, and the reaction mixture was analyzed using liquid chromatography‐tandem mass spectrometry. A total of eight metabolites were detected in human liver microsomes and structurally characterized based on mass spectral data. The main metabolic pathways involved hydroxylations or oxygenations. The identified metabolites were mono‐oxygenated metabolites (M1 and M4), mono‐hydroxylated metabolites (M3, M5, M6, M7, and M8), and a di‐oxygenated metabolite (M2). The detection of these metabolites could confirm the presence of CP 47,497 in biological samples; therefore, collectively, they would be excellent indicators of “Spice” drug abuse.  相似文献   

13.
Previous research on the RAG color‐coded prioritization systems for the discovery of clandestine graves has not considered all the factors influencing the burial site choice within a GIS project. The goal of this technical note was to discuss a GIS‐based quantitative approach for the search of clandestine graves. The method is based on cross‐referenced RAG maps with cumulative suitability factors to host a burial, leading to the editing of different search scenarios for ground searches showing high‐(Red), medium‐(Amber), and low‐(Green) priority areas. The application of this procedure allowed several outcomes to be determined: If the concealment occurs at night, then the “search scenario without the visibility” will be the most effective one; if the concealment occurs in daylight, then the “search scenario with the DSM‐based visibility” will be most appropriate; the different search scenarios may be cross‐referenced with offender's confessions and eyewitnesses’ testimonies to verify the veracity of their statements.  相似文献   

14.
The postmortem interval (PMI) of skeletal remains is a crucial piece of information that can help establish the time dimension in criminal cases. Unfortunately, the accurate and reliable determination of PMI from bone continues to evade forensic investigators despite concerted efforts over the past decades to develop suitable qualitative and quantitative methods. A relatively new PMI method based on the analysis of citrate content of bone was developed by Schwarcz et al. The main objective of our research was to determine whether this work could be externally validated. Thirty‐one bone samples were obtained from the Forensic Anthropology Center, University of Tennessee, Knoxville, and the Onondaga County Medical Examiner's Office. Results from analyzing samples with PMI greater than 2 years suggest that the hypothetical relationship between the citrate content of bone and PMI is much weaker than reported. It was also observed that the average absolute error between the PMI value estimated using the equation proposed by Schwarcz et al. and the actual (“true”) PMI of the sample was negative indicating an underestimation in PMI. These findings are identical to those reported by Kanz et al. Despite these results this method may still serve as a technique to sort ancient from more recent skeletal cases, after further, similar validation studies have been conducted.  相似文献   

15.
Soil forensics utilizes extensive soil information to answer legal questions and test hypotheses. The main difficulty often is the determination of different variables from a small amount of soil sample collected on the suspect. We developed a sequential mineralogical and chemical analyses to assess a limited quantity of soil vestiges (0.5 g) from a suspect's vehicle (adhered to the outside rear-view mirror and to the left front fender) involved in a murder case and compared them with the surface samples found at the victim's body disposal site at the Graciosa Road, Paraná State, Brazil. All results affirm that the suspect’s vehicle could have been in contact with the edge of the Graciosa Road, approximately the place where the victim’s body was located. As a result of the soil analysis and comparison, the results support the likely contact of the suspect’s vehicle with the crime scene.  相似文献   

16.
The “Blue Whale Challenge” is a dangerous Internet phenomenon. As per media reports, it involves a series of life‐threatening tasks imposed by a “curator” to “players,” who must fulfill the whole list, and it ends with the suicide of the player. The authors report the data of five suspected cases of “Blue Whales” managed from January 2016 to December 2017 by the staff of a unit (the “Bambi Unit” of the Pediatric Hospital “Regina Margherita” of Turin, Italy) that is dedicated to the evaluation of suspected abused children. Then, they analyzed this data in the light of the literature regarding self‐harm. This comparison highlights the role of the Internet in the spreading of self‐harm behavior among vulnerable adolescents who are characterized by epidemiological, psychological, psychiatric, social, and cultural risk factors. In conclusion, the authors suggest a multidisciplinary and specialized approach in the evaluation of adolescents who committed self‐harm activities.  相似文献   

17.
Abstract: This study evaluates the use of polydimethylsiloxane polymer composites (PDMS, Fe–PDMS) as a passive sampling media to preconcentrate analytes found in environmental settings. Samplers were made using commercially available silicone products. The composite samplers were assessed for their sorption properties using Atrazine and Irgarol 1051 as model compounds. The initial study assessed the utility of PDMS sheets as adsorption material by following analyte depletion from spiked water samples by solid‐phase microextraction gas chromatography/mass spectrometry (GC/MS). Follow‐up studies conducted at high and low concentrations using lab manufactured iron‐ PDMS rods (Fe–PDMS) showed effective uptake at differential rates from concentrations ranging between 1 μg/L and 10 μg/L. Adsorption mechanism was reversible, and compounds were recovered from the exposed materials and analyzed by liquid–liquid extraction‐GC/MS. Both composites showed better affinity for Irgarol 1051, 100% removal, than for Atrazine, 30% removal, likely representing their KOW differences, 3.6 and 2.6, respectively. This “proof of concept” study demonstrates the positive implications for the use of silicon polymer composites as a monitoring tool for environmental forensic purposes.  相似文献   

18.
Soil has the potential to be valuable forensic evidence linking a person or item to a crime scene; however, there is no established soil individualization technique. In this study, the utility of soil bacterial profiling via next‐generation sequencing of the 16S rRNA gene was examined for associating soils with their place of origin. Soil samples were collected from ten diverse and nine similar habitats over time, and within three habitats at various horizontal and vertical distances. Bacterial profiles were analyzed using four methods: abundance charts and nonmetric multidimensional scaling provided simplification and visualization of the massive datasets, potentially aiding in expert testimony, while analysis of similarities and k‐nearest neighbor offered objective statistical comparisons. The vast majority of soil bacterial profiles (95.4%) were classified to their location of origin, highlighting the potential of bacterial profiling via next‐generation sequencing for the forensic analysis of soil samples.  相似文献   

19.
To date, there is no systematic investigation of the association of short tandem repeat (STR) typing success rate in soft tissues with different signs of putrefaction. Herein, putrefaction was rated using a newly developed 19‐parameter system in soft tissues from a collective of 68 decaying bodies, and DNA yield was determined in 408 samples. DNA integrity was rated using a self‐devised pentaplex PCR generating an “integrity score” (Si). STR typing success rate was then assessed for selected cases. DNA yield and Si differed significantly between tissues with kidney on average exhibiting the highest Si values. Statistical analysis revealed that nine parameters were significantly and positively correlated with Si. The observed values for each of these nine parameters were summed up to generate a putrefaction score (Sp) for each sample. Our results show that STR typing success rate can be predicted based on Sp before expensive multiplex STR profiling is performed.  相似文献   

20.
Reexamination and reinterpretation of the “mature” (1955–1984) New Deal era of congressional attacks on the Supreme Court reveals a new hypothesis: that Court‐curbing efforts played a previously unrecognized role in party system development. Court rulings that create inter‐ and intraparty tension provide opportunities for various actors to attack the Court in an effort to solidify their faction's standing within national coalitional politics. Congressional attackers can use Court‐curbing resolutions and amendments in efforts to help them maintain coalitional cohesion, build a new majority, or consolidate previous victories. Thus, we might see legislative‐judicial relations as an unrecognized “site” of political development, where coalitional change is opposed and wrought.  相似文献   

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