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1.
A rapid method for screening drug seizure samples for 3,6-diacetylmorphine (heroin), which consists of a simple hydrolysis procedure and flow-injection analysis with two chemiluminescence reagents, is described. Before hydrolysis, 3,6-diacetylmorphine evokes an intense response with a tris(2,2'-bipyridyl)ruthenium(III) reagent (prepared by dissolving the perchlorate salt in acetonitrile), and a relatively weak chemiluminescence response with a second reagent: potassium permanganate in an aqueous acidic polyphosphate solution. However, the permanganate reagent is extremely sensitive toward the hydrolysis products of 3,6-diacetylmorphine (i.e., 6-monoacetylmorphine and morphine). Some compounds commonly found in drug laboratories may cause false positives with tris(2,2'-bipyridyl)ruthenium(III), but do not produce the markedly increased response with the permanganate reagent after the hydrolysis procedure. The combination of these two tests therefore provides an effective presumptive test for the presence of 3,6-diacetylmorphine, which we have verified with 14 samples obtained from a forensic science laboratory.  相似文献   

2.
Conventional development of latent fingerprints is compromised when the prints are decomposed by extreme temperatures, such as those encountered when a weapon cartridge is fired, an improvised explosive device is detonated, and/or in arson cases. Understanding how these extreme temperatures alter the chemical and physical properties of latent fingerprint residue could aid in the discovery of a reagent that could effectively develop these decomposed fingerprints. To mimic scenarios where fingerprints may be exposed to high heat conditions, standards of the five most abundant amino acids in fingerprint residue as well as extracted fingerprint residue were pyrolized under controlled conditions. Compounds identified as pyrolytic decomposition products were 3,6-dimethylpiperazine-2,5-dione (from alanine), maleimide, and 2,5-furandione (from aspartic acid). The pyrograms and selected ion traces show these products to hold promise as indicators of decomposed fingerprint residues and, therefore, may serve as good candidate substrates for a developing reagent.  相似文献   

3.
A new microcrystal test for the detection of gamma-hydroxybutyrate (GHB) is described. The silver/copper reagent consists of an aqueous solution of 0.1 g of cupric nitrate and 0.1 g of silver nitrate in 10.0 mL water. While some crystals form upon evaporation of the reagent, the test forms distinctive crystals for GHB and does not form crystals with some commonly encountered controlled substances. The reagent was also tested against some controlled substances that have similar biological activity to GHB, including flunitrazepam, and some barbiturates. No crystals were observed with these compounds. A blind test was performed to determine if GHB could be discriminated from the other compounds. Two of ten unknowns were correctly identified as GHB--one solid, one liquid. One GHB sample was not identified as GHB and the remaining seven non-GHB samples were not identified as GHB. The reagent is therefore selective for GHB, but not extremely sensitive.  相似文献   

4.
Objective documentation of tears and abrasions to the external genitalia after sexual assault is an important part of the forensic examination. A 1% aqueous solution of toluidine blue (TB) dye is often used to highlight injury, but the dye can be difficult to see on dark skin. We evaluated a fluorescent dye for detecting injuries on all skin colors in a relevant preclinical murine model. We compared the ability of trained, blinded observers to detect unstained wounds and wounds stained with 1% fluorescein sodium (FL) and with TB. We also evaluated the cutaneous wound healing response after application of both dyes. The no‐dye group had significantly fewer (p < 0.05) true‐positive identifications compared to all the dye groups. No differences in effectiveness were detected between dye treatments. All groups exhibited statistically similar healing rates. These findings support the evaluation of fluorescein sodium in a future clinical study with human subjects.  相似文献   

5.
目的探索长潜伏期听觉诱发电位(auditory long latency response,ALR)潜伏期、波幅与声刺激强度间的关系和特点,并探讨其在听阈评估中的意义。方法对46名听力正常人(92耳)进行ALR测试,予受试者从70、50、30、20至10 dB nHL 5个声刺激强度顺序诱发ALR波形,标记N_1波、P_2波,得出三个观察指标(N_1波及P_2波潜伏期、N_1-P_2波幅)的数值。分析观察三个指标的变化趋势及频率差异性。结果 46名听力正常人(92耳)ALR波形的引出率均为100%。随着声刺激的降低,ALR的N_1波、P_2波潜伏期延长,N_1-P_2波幅降低。结论在适宜的条件下,ALR是一项稳定的检测技术。ALR的N_1波、P_2波潜伏期及N_1-P_2波幅与声刺激强度间的关系对ALR应用于听阈评估中有重要作用。  相似文献   

6.
This paper describes a procedure for the determination of psilocin and psilocybin in mushroom extracts using high-performance liquid chromatography with postcolumn chemiluminescence detection. A number of extraction methods for psilocin and psilocybin in hallucinogenic mushrooms were investigated, with a simple methanolic extraction being found to be most effective. Psilocin and psilocybin were extracted from a variety of hallucinogenic mushrooms using methanol. The analytes were separated on a C12 column using a (95:5% v/v) methanol:10 mM ammonium formate, pH 3.5 mobile phase with a run time of 5 min. Detection was realized through a dual reagent chemiluminescence detection system of acidic potassium permanganate and tris(2,2'-bipyridyl)ruthenium(II). The chemiluminescence detection system gave improved detectability when compared with UV absorption at 269 nm, with detection limits of 1.2 x 10(-8) and 3.5 x 10(-9) mol/L being obtained for psilocin and psilocybin, respectively. The procedure was applied to the determination of psilocin and psilocybin in three Australian species of hallucinogenic mushroom.  相似文献   

7.
An enhancement of the microcrystalline test for the detection of gamma-hydroxybutyrate (GHB) is described. The original test used a silver/copper reagent which consisted of 0.1 g of silver nitrate and 0.1 g of copper nitrate in 10 mL water. The enhanced test utilizes lanthanum nitrate in place of copper nitrate. A detection limit of 0.5 mg/mL was achieved and the visual discrimination was improved because of larger sized crystals. Transient crystals were observed between 0.1 and 0.4 mg/mL. Silver nitrate alone appeared to be suitable for GHB detection but was not specific as other hydroxyl acids, such as glycolic acid, produced a similar crystal pattern. Tests conducted on chemical precursors of GHB and substances with similar biological activity highlight the specificity of the enhanced test. The reagent is therefore selective and sensitive for GHB in aqueous solutions. However, in beverage testing, crystal formation appeared to be inhibited for some drinks. Citric acid was identified as a possible interference depending on its concentration relative to GHB.  相似文献   

8.
The present research is aimed to introduce Heel-ball (HB) index from foot dimensions and determine whether this index exhibits sexual dimorphism. The study was conducted on a sample of 303 North Indian individuals (154 men, and 149 women) aged between 13 and 18 years. The stature, body weight, foot breadth at the ball (BBAL), and foot breadth at heel (BHEL) were measured. The HB index was derived by the formula BHEL × 100/BBAL. Although the mean HB index was larger in women in both feet it showed statistically significant sex differences in the right foot only. The study shows that while the foot dimensions show a positive correlation with stature and weight, the HB index is independent of the stature and weight of an individual. This novel index (HB index) may be utilized in sex determination when a part of the foot is brought for medico-legal investigation.  相似文献   

9.
Forensic strategies commonly are proceeding by analysis of short tandem repeats (STRs); however, new additional strategies have been proposed for forensic science. Thus, this article standardized the high‐resolution melting (HRM) of DNA for forensic analyzes. For HRM, mitochondrial DNA (mtDNA) from eight individuals were extracted from mucosa swabs by DNAzol reagent, samples were amplified by PCR and submitted to HRM analysis to identify differences in hypervariable (HV) regions I and II. To confirm HRM, all PCR products were DNA sequencing. The data suggest that is possible discriminate DNA from different samples by HRM curves. Also, uncommon dual‐dissociation was identified in a single PCR product, increasing HRM analyzes by evaluation of melting peaks. Thus, HRM is accurate and useful to screening small differences in HVI and HVII regions from mtDNA and increase the efficiency of laboratory routines based on forensic genetics.  相似文献   

10.
The regulations for gasoline's content vary depending on the time of year and physical location within the United States while the refinery and distribution system mixes product batches; this results in variability of content. ASTM E1618 requires both the aromatic and alkane EIP patterns of gasoline to compare with references. A survey was conducted by collecting gasoline from Florida to Oregon, from 85 to 93 octane. Samples were analyzed in accordance with ASTM E1618 in various states of evaporation. The range of differences found in the 90% evaporated alkane EIPs is presented and showed a continuum of response when the n-alkane response was compared with the branched alkane response. Similarly, the ratio of the alkane EIP to the aromatic EIP also showed a continuum of response at the 90% evaporated state. Gasoline samples with unusual characteristics are also discussed.  相似文献   

11.
Abstract: The purpose of this study was to develop age‐predicting equations from the anterior cortex of the femur of Korean adults. Seventy‐two femoral samples (44 male and 28 female) were obtained from Korean cadavers and used to develop the equations. The thin sections (<100‐μm thick) were prepared by manual grinding; the sections were not decalcified and were stained with Villanueva bone stain reagent. Analysis of covariance showed no significant differences in age‐adjusted histomorphological variables between sexes. In stepwise regression analysis, osteon population density, average osteon area, and the most anterior cortical width were selected for an age‐predicting equation which produced a high regression correlation (R2 = 0.789). The average Haversian canal area was not significantly related to age for any specimen.  相似文献   

12.
Vitreous fluid sampling for postmortem chemistry analysis is discouraged in pediatric forensic cases involving head trauma due to the risk of introducing retinal artifacts. Aqueous fluid is physically separated from the posterior chamber of the eye, and therefore, unlikely to produce vitreal artifact when sampled. Analysis of aqueous fluid is therefore proposed as a substitute for vitreous. Vitreous and aqueous fluid was sampled concurrently from 28 pediatric and 55 adult decedents, and sodium (Na), potassium (K), chloride (Cl), urea nitrogen (UN), creatinine (Cr), and glucose (Glc) concentrations were compared. Significant correlation existed between all analytes regardless of age or postmortem interval, and linear regression equations were derived. Aqueous concentrations were generally higher than vitreous for Na, K, and Cr and were marginally lower for Cl, UN, and Glc. Assuming vitreous fluid as a standard for correlating postmortem chemistry to antemortem serum values, aqueous may be a viable substitute for vitreous when expected differences are considered.  相似文献   

13.
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.  相似文献   

14.
The aim of this retrospective study was to examine methyl alcohol intoxications in Trabzon (Turkey) and to determine any relations between the laboratory results and histopathologic changes. A total of 4492 forensic autopsies were performed from 1998 to 2008. Thirteen of the cases (0.3%) were because of methanol poisoning, and all were men. Their ages ranged from 25 to 62 years. The blood methanol concentrations ranged widely, from 15 to 482 mg/dL. In six cases, poisoning was because of consumption of the alcoholic beverage "Raki," while in five cases, poisoning was because of the ingestion of cologne. The products consumed were unknown in the other two cases because of insufficient history and data records. Mortality because of methanol poisoning may be prevented/decreased with the implementation of some precautions, such as public education regarding the harms of methyl alcohol, routine monitoring of the vendors that sell alcoholic beverages and cologne, and appropriate legal retribution for the illegal production of methanol.  相似文献   

15.
Denture marking (DM) helps identify edentulous people with different methods. Analyzing perceptions and attitudes of denture wearers would enable understanding of the practical aspects, an analysis still absent in South America. Fifty‐three individual candidates for removable dentures were instructed on disaster victim identification (DVI) and the usefulness of DM for this purpose. They were physically shown eight DM systems and a questionnaire to which they responded by highlighting preferences in those systems. Although 98.11% did not know that dentures could be marked, only 9.43% denied interest in some type of DM. The 90.57% would mark their dentures with some system, preferring the inclusion of QR codes or a micro SIM card. The proven weaknesses of DVI and propensity for disaster mean this community in Chile is an opportunity to implement DM systems. Obstacles may come not from patients but from their dentists, educational institutions, or a lack of public policies.  相似文献   

16.
In the summer of 2005 an adult hiker was killed in a fall in Rocky Mountain National Park, Colorado (U.S.A.). His body was subsequently colonized by the blowfly Calliphora vicina (Diptera: Calliphoridae). The body was discovered 9 days later at an elevation of 3475 m (11,400 feet). This is the first report of C. vicina on a human corpse at this elevation in Colorado. This paper provides additional confirmation of this fly colonizing a human corpse at high elevations in Colorado.  相似文献   

17.
18.
This study investigated the potential effects of flunitrazepam (known as “date rape drug”) on the developmental cycle of Chrysomya megacephala, an important forensic species, and their possible implications for the calculation of the PMI. A 1050 C. megacephala eggs were divided into five groups with seven replications each. The eggs were placed on artificial diet prepared with four drug concentrations of flunitrazepam (4, 8, 16, and 32 ng/g), besides the control group (prepared with water). Were evaluated the potential effects on development time, weight gain, and mortality during the cycles. The drug had no significant effect on development time or mortality although it did affect the weight of the pupae and adults (Kruskal–Wallis, p < 0.05). The result can be deduced that the determination of the postmortem interval is not affected.  相似文献   

19.
Bloodstain pattern analysis can be critical to accurate crime scene reconstruction. However, bloodstain patterns can be altered in the presence of insects and can confound crime scene reconstruction. To address this problem, we conducted a series of controlled laboratory experiments to investigate the effect of Lucilia sericata (Meigen) on impact bloodstains and pooled bloodstains in association with three combinations of common surfaces (linoleum/painted drywall, wood floor/wallpaper, and carpet/wood paneling). L. sericata fed from the pooled bloodstains and added insect stains through regurgitation and defecation of consumed blood. L. sericata formed defecatory trails of insect stains that indicated directionality. Defecatory stains fluoresced when viewed at 465 nm with an orange filter. These observations differed from Calliphora vicina insect stains because feeding on blood spatter was not observed and trails of insect stains were formed by L. sericata. The fluorescence of defecatory stains can be used as a method to detect insect stains and discriminate them from real bloodstains.  相似文献   

20.
Photography is widely accepted as a means of forensic case documentation and evaluation. In cases of criminal dismemberment digital microscopy is commonly used to assess marks left on the bone. Reflectance transformation imaging (RTI) is a computational photography technique which documents and enhances the three-dimensional (3D) reflectance properties of the surface of an object. RTI has primarily been used in the cultural heritage sector but has recently transitioned into forensic science. This study examines the use of RTI for the documentation and presentation of cut surface characteristics on fully sectioned long bones. Juvenile pig radii were bisected using three different handsaws, chosen as handsaws are the most common implement used in criminal dismemberments. The resulting 42 cut surfaces were then documented with a digital microscope and RTI. Four rendering modes were applied to the default RTI image, with diffuse gain being the most beneficial to accentuate cut surface features. Although great care must be taken when obtaining the photographic sequences necessary for detailed RTI analysis, RTI is relatively inexpensive, expeditious, and easy to use, and creates highly detailed, virtually interactive images. RTI may not replace microscopic methods of saw mark analysis, however could prove useful for the documentation, image sharing, and presentation of forensic evidence.  相似文献   

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