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101.
Stephanie K. Bell B.S. B.A. Piero R. Gardinali Ph.D. 《Journal of forensic sciences》2010,55(5):1245-1250
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
102.
Eun J. Lee Ph.D. In K. Hwang M.S. Nam Y. Kim M.D. Kyung L. Lee Ph.D. Myun S. Han Ph.D. Yang H. Lee Ph.D. Mu Y. Kim Ph.D. Moon S. Yang Ph.D. 《Journal of forensic sciences》2010,55(5):1202-1208
Abstract: The proper identification of illicit plants such as Papaver somniferum L (opium poppy) is important for law enforcement agencies. The identification of opium poppy was presently tested using 10 genetic markers that are universal for all plants or specific to a few poppy plants. The genetic distances of universal markers such as nuclear internal transcribed spacer (ITS), 18S rRNA, plastid rbcL, and trnL‐trnF intergenic spacer (IGS) of 14 species included in the Papaveraceae and Fumariaceae family were acquired by sequence comparisons. Both the ITS region and trnL‐trnF IGS showed high levels of interspecific divergence. Six Papaver genera‐specific markers were developed from coding regions involved in morphine biosynthesis. Three markers (TYDC, NCS, and BBE) produced amplicons only in opium poppy, providing a presence/absence test for opium poppy, while three additional markers (CYP80B1, SAT, and COR) were genus specific. These 10 markers might be useful for the forensic DNA analysis of opium poppy. 相似文献
103.
G K Murphy 《The American journal of forensic medicine and pathology》1991,12(2):98-101
Although gunshot is by far the most common means of homicide in the United States, significant numbers of homicides are also perpetrated by other means. Blunt-force injuries are produced by a variety of objects, including hands and feet and many different weapons. Some of these objects produce distinctive patterns of injury of potential evidentiary value. This paper presents a series of 20 consecutive blunt-force homicides in adults. Seventy percent (14 cases) of the victims were men. Thirty percent (six cases) followed an argument or altercation. A number of the weapons used were "weapons of opportunity" seized in the course of the incidents. Sixty-nine percent (nine cases) of known assailants were acquainted with their victims. Few characteristic patterned injuries were seen. Not surprisingly, craniocerebral trauma was the most common cause of death. One half (10 cases) the victims survived their assaults for varying periods of time. Homicides due to blunt-force injury still pose a significant challenge for the forensic pathologist, who must obtain a complete and accurate history of the fatal incident, interpret patterns of injury and other findings at autopsy, and correlate all of the findings to make an accurate ruling of the cause and manner of death. 相似文献
104.
Determination of methamphetamine and amphetamine in hair was performed by gas chromatography/mass spectrometry using stable isotope-labeled internal standards, 2-methylamino-1-phenylpropane-2,3,3,3-d4 and 2-amino-1-phenylpropane-2,3,3,3-d4. Extraction of hair with methanol/5M hydrochloric acid (20:1) using ultrasonication was chosen as the standard method. The calibration curves for amphetamines in the hair were linear from 1 to 100 ng/mg (r greater than 0.99). The detection limit was 0.5 ng/mg at the 95% confidence level. The coefficients of variation (CV) (n = 8) of analysis using the spiked hair with methamphetamine were from 0.7 to 6%. The CV (n = 8) of analysis of the methamphetamine abuser's hair was 17.5%. Sectional analysis of monkey and human hair after methamphetamine ingestion suggested a good correlation between the duration of drug use and drug distribution in the hair. 相似文献
105.
K. Minakata O. Suzuki Y. Ishikawa H. Seno M. Asano 《Forensic Science International Supplement Series》1991,50(2)
A simple and sensitive method is described for quantitative analysis of chlorpromazine in blood, serum, urine and tissue homogenate. The chlorpromazine cation radical produced by adding perchloric acid and 2,3-dichloro-5,6-dicyano-p-benzoquinone to the sample can be detected by the ESR method at room temperature. The sensitivity limit is 10 ng, that is, 20 μl of the solution containing 0.5 μg chlorpromazine/ml. The time needed for the measurement is within 10 min. The chlorpromazine radical thus produced is very stable; for example, 95% of the radical was observed after 24 h. The advantage of this method is discussed by comparing with the ordinary spectrophotometry which requires the purification of the sample. 相似文献
106.
V.K. Sharma R.K. Jadhav G.J. Rao A.K. Saraf Heeresh Chandra 《Forensic Science International Supplement Series》1991,50(2)
A method has been developed on reverse phase high performance liquid chromatography for simultaneous determination of methyl, ethyl and isopropyl alcohols under refractive index detection using pure water as the mobile phase. A good separation has been achieved between these alcohols. Detector response was linear with a detection limit of 5 mg/100 ml. Recovery studies were performed by adding known amounts of methyl and ethyl alcohols to blood, lung and liver within the range 80–90%. The reproducibility of the results was always >90%. The quantitative distribution of methyl alcohol in postmortem body tissues and fluids has been reported in three cases of poisoning. 相似文献
107.
LESLEY K. MCALLISTER 《Law & policy》2010,32(1):61-78
This article explores how the concept of enforcement style can be adapted to be more analytically useful in the study of regulatory behavior and its effects in developing countries. In its first part, the article sets forth a dimensional conception of enforcement style and suggests two new dimensions to incorporate the variations in the autonomy and capacity of regulatory agencies that are so significant in developing countries. In its second part, the article uses this analytical framework to compare the enforcement styles of state environmental agencies in two Brazilian states, São Paulo and Pará. 相似文献
108.
Carol K. Lee M.D. F.R.C.P.C. Sarah L. Lathrop D.V.M. Ph.D. 《Journal of forensic sciences》2010,55(1):100-103
Abstract: We retrospectively reviewed autopsy records at a statewide medical examiner's office in order to identify and characterize deaths due to child abuse. In a 6-year period in New Mexico, the medical examiner investigated 45 deaths determined to be child abuse-related. Decedents were predominantly male (68.9%), Hispanic White (53.3%), and all were 5 years of age or younger, with a median age of 1 year. Head injuries were the most common cause of death (44.4%), followed by battered baby syndrome (15.6%). Relatives were involved as alleged perpetrators in 80% of the cases, with the father most often implicated (36.1% of cases), and 88.9% of child abuse injuries resulting in death occurred in the family's residence. Toxicology was positive in 26.7% of cases, but only two cases had substances of abuse present. Information on risk factors such as prematurity, parental age, and history of abuse was also collected. 相似文献
109.
Richard K. Caputo 《Social Justice Research》2002,15(3):271-293
This paper reports results of a study based on a nationally representative sample of U.S. youth (N = 11,549) that asked two questions: (1) How does family structure affect the likelihood of adolescent death beyond that of race/ethnicity, sex, socioeconomic status, personal behavior, and other structural factors and (2) under what conditions might appeals for social justice be warranted for relative mortality statuses and for absolute gains in mortality? The study found that marital instability increases the likelihood of dying when controlling for a variety of other factors including class, race/ethnicity, sex, and unemployment rate in area of residence. The author argues that this finding lends support to social justice arguments to redistribute resources in such a way as to ensure the likelihood of absolute gains in mortality. The study also found, however, that race/ethnicity/sex also accounted for the likelihood of dying independently of family structure when controlling for socioeconomic and other factors. The author argues that this finding lends support to social justice arguments to redistribute resources on the basis of relative mortality statuses. 相似文献
110.
A simple technique is presented for the longitudinal sectioning of hair samples without the need for any embedding medium. The technique applies to single hair samples that are placed in a groove of a particular depth and can either be scraped or cut to the desired level. Planar sections are obtained that reveal the internal structure of the sample and are ideal for the application of surface analytical techniques for the study of internal transverse and longitudinal distributions of xenobiotics. 相似文献