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1.
Following the September 11, 2001 terrorist attacks, letters containing Bacillus anthracis were distributed through the United States postal system killing five people. A complex forensic investigation commenced to identify the perpetrator of these mailings. A novel liquid chromatography/mass spectrometry protocol for the qualitative detection of trace levels of meglumine and diatrizoate in dried spore preparations of B. anthracis was developed. Meglumine and diatrizoate are components of radiographic imaging products that have been used to purify bacterial spores. Two separate chromatographic assays using multiple mass spectrometric analyses were developed for the detection of meglumine and diatrizoate. The assays achieved limits of detection for meglumine and diatrizoate of 1.00 and 10.0 ng/mL, respectively. Bacillus cereus T strain spores were effectively used as a surrogate for B. anthracis spores during method development and validation. This protocol was successfully applied to limited evidentiary B. anthracis spore material, providing probative information to the investigators.  相似文献   

2.
Bacterial species with high DNA sequence similarity to pathogens could affect the specificity of assays designed to detect biological threat agents in environmental samples. The natural presence of four pathogenic bacteria, Bacillus anthracis, Clostridium perfringens, Francisella tularensis, and Yersinia pestis and their closely related species, was determined for a large collection of soil and aerosol samples. Polymerase chain reaction (PCR) and gene sequencing were used using group-specific 16S rRNA primers to identify pathogens and related species, and pathogen-specific virulence genes. Close relatives of B. anthracis (B. cereus group species) were detected in 37% of the soils and 25% of the aerosol samples. The B. anthracis protective antigen (pag) gene or a close homolog was detected in 16 of these samples. For the other three pathogen groups, the frequency of detection was much lower, and none of the samples were positive with both the phylogenetic and virulence gene primer sets.  相似文献   

3.
Motivated by the debate over how to deal with the huge backlog of untested sexual assault kits in the U.S.A., we construct and analyze a mathematical model that predicts the expected number of hits (i.e., a new DNA profile matches a DNA sample in the criminal database) as a function of both the proportion of the backlog that is tested and whether the victim–offender relationship is used to prioritize the kits that are tested. Refining the results in Ref. (Criminol Public Policy, 2016, 15, 555), we use data from Detroit, where government funding was used to process ≈15% of their backlog, to predict that prioritizing stranger kits over nonstranger kits leads to only a small improvement in performance (a 0.034 increase in the normalized area under the curve of the hits vs. proportion of backlog tested curve). Two rough but conservative cost‐benefit analyses—one for testing the entire backlog and a marginal one for testing kits from nonstranger assaults—suggest that testing all sexual assault kits in the backlog is quite cost‐effective: for example, spending ≈$1641 to test a kit averts sexual assaults costing ≈$133,484 on average.  相似文献   

4.
In recent years, drugs including flunitrazepam, gamma-hydroxybutyrate, ketamine, and ethanol, have become popularly associated with drug-facilitated sexual assault. Other drugs are also candidates as factors in "drug facilitated sexual assault" (DFSA). The true extent of DFSA is not known, and is difficult to estimate. We recruited sexual assault complainants at four clinics in different parts of the U.S. to anonymously provide urine and hair specimens, and to answer questions about suspected drugging, drug use, and the sexual assault incident. Urine and hair specimens were tested for 45 drugs, including ethanol, and those pharmacologically capable of inducing sedation, amnesia, or impairment of judgment. Analytical test results were used to estimate the proportion of subjects, and the proportion of all complainants to the clinic in the same time period, who were victims of DFSA. Overall, cases of 43% of 144 subjects, and 7% of 859 complainants, were characterized as DFSA. Subjects underreported their use of drugs. The role of toxicological results and history in characterizing DFSA cases is discussed.  相似文献   

5.
This study presents a method by which to estimate total body mass in modern young adult U.S. populations who self‐identified as non‐Hispanic U.S. White, non‐Hispanic U.S. Black, and Mexican American with anthropometric measurements from the Third National Health and Nutrition Examination Survey (NHANES III) 1988–1994 dataset (N = 2532). Correlations of stature and bi‐iliac breadth with total body mass were stronger among males (r = 0.717–0.774) than among females (r = 0.549–0.661), yet these results were more accurate assessments of total body mass than existing techniques. This study also examined additional anthropometric measurements to estimate total body mass using an information‐theoretic approach demonstrating that some error in the stature–bi‐iliac breadth method is attributed to a nonsupported model with multimodel inference. The limitations of the current total body mass technique are discussed as well as the need for future studies to validate the method.  相似文献   

6.
It has long been suspected that the illicit distribution of cocaine in the United States has led to a large‐scale contamination of the currency supply. To investigate the extent of contamination, 418 currency samples (4174 bills) were collected from 90 locations around the United States from 1993 to 2009. The extent of their cocaine contamination was quantitated via gas chromatography/mass spectrometry or liquid chromatography/mass spectrometry. The level of cocaine contamination was determined to average 2.34 ng/bill across all denominations ($1, $5, $10, $20, $50, and $100). Levels of cocaine contamination on currency submitted to the Federal Bureau of Investigation Laboratory in criminal cases over the 1993–2001 timeframe had significantly higher contamination than currency in general circulation. A mathematical model was developed based on the background survey that indicates the likelihood of drawing a bill in specific concentration ranges. For example, there is a 0.8349 likelihood that random bill will have contamination less than 20 ng.  相似文献   

7.
Carrion flies in the taxonomic family Sarcophagidae are often recovered from a human corpse. However, because such specimens are difficult to identify, the forensic literature on this taxon is quite limited compared with that of the commonly employed Calliphoridae. Faced with a sarcophagid larva that could not be identified microscopically from a death investigation in the state of Idaho, we generated cytochrome oxidase one DNA sequence data from the specimen. Comparison to a reference data set of forensically significant sarcophagids from Canada and the U.S.A. confirmed that this was the first discovery of Blaesoxipha plinthopyga in a human corpse in the U.S.A. and the first record of this species in Idaho. Because B. plinthopyga occurs from the Northern U.S.A. to the Neotropics, it is potentially useful for estimating time since death at many locations.  相似文献   

8.
This paper tests the fidelity of a recent method that used the NHANES III dataset as a proxy to estimate total body mass from stature and bi‐iliac breadth in U.S. White males and females. The bi‐iliac breadths of 230 males and 152 females identified as non‐Hispanic U.S. White from the Bass Donated Skeletal Collection were measured, and along with stature from predonor paperwork, total body mass estimates were calculated and then compared to body masses recorded on predonor paperwork. Male and female samples were subdivided by body mass index (BMI [kg/m2]) categories established by the World Health Organization. Our results suggest that total body mass estimates can be accurately assessed provided that the individual is within 18.50 ≤ BMI ≤ 29.99 for White males and 18.50 ≤ BMI ≤ 24.99 for White females. Recommendations on how to report total body mass estimates are also presented.  相似文献   

9.
Several studies have reported on wide‐spread contamination of U.S. paper currency with cocaine and to a lesser extent other illicit drugs. Canines are trained and employed to search for and alert to drugs. Canine alert to currency has been used as evidence that currency has been directly involved in illicit drug trafficking to justify currency seizure and forfeiture. This assertion, particularly when the only evidence is based upon canine alert, has been challenged in the courts considering that most currency in circulation is contaminated with cocaine. Comprehensive review of the scientific literature establishes that (i) 67–100% of circulated U.S. currency is contaminated with cocaine ranging from a few nanograms to over one milligram/bill (ii) various biological and environmental parameters impact canine alert to drugs. It is concluded that canine alert to U.S. currency is not sufficiently reliable to determine that currency was directly used in an illicit drug transaction.  相似文献   

10.
Recently, Hefner and Ousley (2014) introduced the optimized summed scored attributes (OSSA) method that maximizes between‐group differences in U.S. black and white populations by dichotomizing six cranial morphoscopic trait scores. This study tests OSSA using an independent skeletal sample (Hamann‐Todd, n = 208) and positively identified forensic cases (Mercyhurst University, n = 28, and New York City Office of Chief Medical Examiner, n = 38). An evaluation of trait frequencies suggests shifting the heuristically selected sectioning point separating U.S. black and white populations from ≤ 3 to ≤ 4. We found a total correct classification of 73.0% (B = 50.9%, W = 89.2%) using the originally suggested sectioning point of ≤3, while the total correct classification increases to 79.2% (B = 80.2%, W = 78.5%) with a modified sectioning point of ≤4. With the increased total correct classification and reduced classification bias between ancestry groups, we suggest the modified sectioning point of ≤4 be used when assessing ancestry in forensic unknowns.  相似文献   

11.
Recovery, profiling, and speculative searching of trace DNA (not attributable to a body fluid/cell type) over a twelve‐month period in a U.S. Crime Laboratory and U.K. police force are compared. Results show greater numbers of U.S. firearm‐related items submitted for analysis compared with the U.K., where greatest numbers were submitted from burglary or vehicle offenses. U.S. multiple recovery techniques (double swabbing) occurred mainly during laboratory examination, whereas the majority of U.K. multiple recovery techniques occurred at the scene. No statistical difference was observed for useful profiles from single or multiple recovery. Database loading of interpretable profiles was most successful for U.K. items related to burglary or vehicle offenses. Database associations (matches) represented 7.0% of all U.S. items and 13.1% of all U.K. items. The U.K. strategy for burglary and vehicle examination demonstrated that careful selection of both items and sampling techniques is crucial to obtaining the observed results.  相似文献   

12.
Low recovery rate of intact crania in conflict‐related contexts necessitates the use of postcranial elements for ancestry estimation. This study aimed to develop a new method to discriminate between Korean and U.S. White casualties from the Korean War using vertebrae. Maximum body heights of C2 through L5 were measured from 75 Korean and 51 U.S. males to generate discriminant functions. U.S. vertebral heights were statistically greater than Koreans in 18 out of 23 vertebrae (C2, C4‐6, T3‐6, and T8‐L5). The functions with lumbar vertebrae tended to yield higher correct classification ratios (CCR) than those with cervical or thoracic vertebrae. Inclusion of the femur and tibia lengths in the vertebrae‐involved functions enhanced the CCR's. Discriminant functions using the femur and tibia length were also presented. The results of this study are expected to complement the current practices of the Defense POW/MIA Accounting Agency and the Ministry of National Defense Agency for KIA Recovery and Identification, which are primarily based on cranial and dental morphology.  相似文献   

13.
This paper outlines the sociodemographic, developmental, antecedent attack, attack preparation, and commission properties of 115 mass murderers between 1990 and 2014. The results indicate that mass murderer attacks are usually the culmination of a complex mix of personal, political, and social drivers that crystalize at the same time to drive the individual down the path of violent action. We specifically focus upon areas related to prior criminal engagement, leakage, and attack location familiarity. Whether the violence comes to fruition is usually a combination of the availability and vulnerability of suitable targets that suit the heady mix of personal and political grievances and the individual's capability to engage in an attack from both a psychological and technical capability standpoint. Many individual cases share a mixture of unfortunate personal life circumstances coupled with an intensification of beliefs/grievances that later developed into the idea to engage in violence.  相似文献   

14.
A DNA database consisting of the 11 Y chromosome short-tandem-repeat (Y-STR) recommended by the Scientific Working Group on DNA Analysis Methods is constructed for 2517 individuals from 38 populations in the United States. The population samples derive from five ethnic groups currently living in 10 states. A multidimensional scaling (MDS) plot places the populations into four discrete clusters (African Americans (AA), European Americans (EA), Hispanic Americans (HA), and Asian Americans (SA)) and one dispersed cluster of Native Americans. An analysis of molecular variance (AMOVA) indicates that a large proportion of the total genetic variance is partitioned among ethnic groups (24.8%), whereas only a small amount (1.5%) is found among-populations within ethnic groups. Separate AMOVA analyses within each ethnic group show that only the NA sample contains statistically significant among-population variation. Pair wise population differentiation tests do uncover heterogeneity among EA and among HA populations; however, this is due to only a single sample within each group. The analyses support the creation of AA, EA, HA, and Asian American databases in which samples from different geographic regions within the United States are pooled. We recommend that separate databases be constructed for different NA groups.  相似文献   

15.
16.
We studied how carbon monoxide (CO) is distributed within the human body through quantitation of CO concentrations in postmortem tissue samples from fatalities including possible CO exposure. Stored, frozen tissues were diced, sonicated in water, and 0.01-8.0 mg wet weight (ww) tissues were incubated with sulfosalicylic acid in CO-purged, septum-sealed vials. CO released into the headspace was quantitated by reduction gas chromatography. Mean tissue CO concentrations (pmol/mg ww) from subjects diagnosed to have no known CO exposure (control, N=14), died from fire (N=13), and CO asphyxiation (N=7), respectively, were: adipose (2;13;9), brain (3;13;65), muscle (15;97;297), heart (30;99;371), kidney (22;432;709, lung (54;690;2638), spleen (73;1366;3548), and blood (162;2238;5070). Carboxyhemoglobin concentrations were 1.4%, 25.2%, and 69.1% of total hemoglobin, respectively. We conclude that measurements of CO concentration in a variety of tissues can be used as markers for the degree of exogenous CO exposure and the identification of possible causes of death.  相似文献   

17.
Through a comparison of fingermark sweat corrosion of α phase brass in both the U.K. and Iraq, we show how samples from Iraq have improved fingermark corrosion over U.K. samples that require no additional enhancement prior to visualization. Over 50% of Iraqi samples produced fingermark corrosion with full ridge detail compared with 0% from the U.K. X-ray photoelectron spectroscopy analysis of the fingermark corrosion products showed that Iraqi samples exhibit more dezincification with the Zn:Cu ratio averaging 1:1.82 compared with 1:3.07 for U.K. samples. Auger spectroscopy showed the presence of both zinc oxide and copper (I) oxide. No copper (II) was observed on the surface of the corroded brass. Opportunities to exploit the optical properties of these thin film oxides to enhance the visualization of fingermark corrosion are considered, and the potential to use fingermark corrosion of metal as a means of visualizing fingerprints in war zones is discussed.  相似文献   

18.
When mitochondrial DNA (mtDNA) heteroplasmies are detected, they often confound forensic identification, especially if they are the result of poor biological sampling. In this study, we determined the ratio of heteroplasmy in samples that were amplified from a very small amount of template mtDNA or a few cells using a highly sensitive nested polymerase chain reaction (PCR) procedure and a direct sequencing analysis. As a result, more than half of the detected sequences (i.e., 17/20, 15/20, and 14/20) showed homoplasmy derived from a variation in the heteroplasmy proportion when only 10 copies of template mtDNA samples were amplified and analyzed. Additionally, with products amplified from one or several white blood cells (WBCs), several previously undetected heteroplasmies were detected. These results indicate the risks associated with using highly sensitive mtDNA techniques in forensic investigations because of the variable proportions of heteroplasmy or nucleotide substitutions that can possibly be detected from a very small biological sample.  相似文献   

19.
In October 2009, the grave of an unknown World War I (WWI) U.S. service member was exhumed in Rembercourt‐Sur‐Mad Village, in the Lorraine Region of France. The skeletal remains and material evidence were accessioned into the Joint POW/MIA Accounting Command's (JPAC) Central Identification Laboratory (CIL). The personnel records for the associated casualty were requested, received, and reviewed. A dental profile was present among the service member's personal information. There were multiple points of concordance between the dental records of the associated casualty, and the recovered dental remains to include eight restored teeth, 15 unrestored teeth, and three antemortem missing teeth. Distinctive restorations which compared favorably included a porcelain crown and multiple gold foil fillings. All lines of evidence (historical, material evidence/personal effects, anthropological, and dental) and the circumstances of loss compared positively with the associated casualty. On April 1, 2010, the previously unaccounted‐for U.S. service member was positively identified and on June 23, 2010, was buried with full military honors at Arlington National Cemetery.  相似文献   

20.
We report on the colonization of an adult human corpse by three insect species at 3350 m (11,000 ft) in elevation. The adult silphid Thanatophilus coloradensis (Wickham), adults of the blow fly Calliphora coloradensis (Hough), and larvae and adults of Lucilia silvarum (Meigen) were all collected from the victim's body which had been wrapped in plastic. The victim was found in late June in the Rocky Mountains of Colorado. This paper provides additional confirmation of the taxa utilizing a human corpse at high elevations in Colorado.  相似文献   

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