Search results for "Forensic Sciences"
showing 10 items of 13 documents
Water content of latent fingerprints - Dispelling the myth.
2016
Abstract Changing procedures in the handling of rare and precious documents in museums and elsewhere, based on assumptions about constituents of latent fingerprints, have led the author to an examination of available data. These changes appear to have been triggered by one paper using general biological data regarding eccrine sweat production to infer that deposited fingerprints are mostly water. Searching the fingerprint literature has revealed a number of reference works similarly quoting figures for average water content of deposited fingerprints of 98% or more. Whilst accurate estimation is difficult there is no evidence that the residue on fingers could be anything like 98% water, even…
A unique fatal case of Waterhouse–Friderichsen syndrome caused by Proteus mirabilis in an immunocompetent subject
2019
Abstract Introduction: The Waterhouse–Friderichsen syndrome (WFS), also known as purpura fulminans, is a potentially lethal condition described as acute hemorrhagic necrosis of the adrenal glands. It is often caused by infection. Classically, Neisseriae meningitidis represents the main microorganism related to WFS, although, infrequently, also other infectious agents are reported as a possible etiologic agent. The authors report the first case of death due to Proteus mirabilis infection, with postmortem evidence of WFS. Patient concerns: After a facial trauma that provoked a wound on the nose, the subject, a healthy 40-years old man, was conducted to the local hospital (in Sicily, Italy) af…
SANIST: optimization of a technology for compound identification based on the European Union directive with applications in forensic, pharmaceutical …
2016
Electrospray Ionization and collision induced dissociation tandem mass spectrometry are usually employed to obtain compound identification through a mass spectra match. Different algorithms have been developed for this purpose (for example the nist match algorithm). These approaches compare the tandem mass spectra of the unknown analyte with the tandem mass spectra spectra of known compounds inserted in a database. The compounds are usually identified on the basis of spectral match value associated with a probability of recognition. However, this approach is not usually applied to multiple reaction monitoring transition spectra achieved by means of triple quadrupole apparatus, mainly due to…
Autopsia de un body packer al que le habían extraído la droga siendo cadáver
2015
Existen multitud de métodos empleados por los narcotraficantes para el traslado internacional de la droga, siendo el más peligroso para el individuo el transporte en el interior de su organismo, el denominado “body packer”. En ocasiones, alguno de los paquetes puede romperse y provocar la muerte por la salida masiva del tóxico. El hallazgo del envoltorio roto y el resto de paquetes íntegros, con la droga en su interior, al realizar la autopsia, son muy importantes para el diagnóstico. En el caso que nos ocupa, la previa manipulación del cadáver para extracción y recuperación de la droga, ha dificultado la determinación de la causa de la muerte. There are many methods used by drug trafficker…
Oxygen isotope composition of North American bobcat (Lynx rufus) and puma (Puma concolor) bone phosphate: implications for provenance and climate rec…
2015
Feline carnivores are threatened by illegal wildlife trade. Tracing the provenance of unknown felid tissues via stable isotope analysis could provide important information in wildlife crime investigations. The oxygen isotope composition of mammalian skeletal phosphate (δ(18)Op) is widely applied to trace the origin of animal remains and to reconstruct migratory patterns in palaeontological, archaeological, ecological and wildlife forensic applications. Teeth and bones of terrestrial mammals form at constant body temperature in isotope equilibrium with body water, which is predominantly controlled by ingested meteoric water (δ(18)Ow) that varies systematically with latitude, altitude and cli…
Validated, non-destructive and environmentally friendly determination of cocaine in euro bank notes.
2005
A non-destructive, fast and environmentally friendly procedure has been developed for cocaine determination in euro bank notes. Cocaine was extracted with 15 ml methanol by vortex agitation during 5 min. The extract was evaporated and reconstituted in 0.5 ml methanol. GC-MS-MS analysis was performed using as precursor ion m/z 182.2, with an excitation energy voltage of 1.60 eV, being the product ions measured m/z 150.2 and 82.0. A limit of detection of 0.15 ng per note and a repeatability of 6%, established from the relative standard deviation, of a 1 ng ml(-1) level, were achieved. Recoveries of 101+/-2 and 98+/-3% were obtained for samples spiked with 100 and 10 microg respectively. Resul…
DNA Evidence Uncompromised by Active Oxygen
2010
Currently, forensic sciences can make use of the potential of instrumental analysis techniques to obtain information from the smallest, even invisible, samples. However, as laboratory techniques improve, so too should the procedures applied in the search for and initial testing of clues in order to be equally effective. This requires continuous revision so that those procedures may resolve the problems that samples present. As far as bloodstains are concerned, there are methods available that are recognized as being both highly sensitive and effective. Nevertheless, the marketing of new cleaning products, those that contain active oxygen, has raised doubts about the ability of those procedu…
Ion mobility spectrometry evaluation of cocaine occupational exposure in forensic laboratories
2014
An approach, based on ion mobility spectrometry (IMS) has been developed for the control of cocaine in air of the breathing zone of operators, in laboratory surfaces and in nasal mucus of employees to evaluate cocaine exposure in a forensic laboratory. The analytical methodology has been validated in terms of accuracy, precision and limits of detection and results obtained were statistically comparable with those obtained by liquid chromatography. Cocaine concentration in laboratory air increases from 100 ± 35 ng m(-3) of a normal day to 10,000 ng m(-3) during the manipulation of cocaine seizures. The occupational exposure limit (OEL) for cocaine has not been established which difficult the…
An Alternative to the Human Hemoglobin Test in the Investigation of Bloodstains Treated with Active Oxygen: The Human Glycophorin A Test
2011
In criminal investigations, there are three stages involved when studying bloodstains: search and orientation, confirmation, and individualization. Confirmatory tests have two aims: to show that the stain contains a human biological fluid and to confirm the type of biological fluid. The need to determine the nature of the evidence is reflected in the latest bibliography, where the possibility of employing mRNA and miRNA markers for this purpose is proposed. While these new proposals are being investigated, the kits for determining human hemoglobin currently provide a simple solution for resolving this issue. With these kits, the possibility of obtaining false positives and false negatives i…
Bloodstains on Leather: Examination of False Negatives in Presumptive Test and Human Hemoglobin Test.
2017
Presumptive tests for blood are very simple and sensitive tests used in the search for evidence. They also provide initial information on the nature of stains. A second test can confirm their nature. However, these tests can present false–negative results for different reasons. Some of those reasons have been studied, while others, those caused by the substrate material that contains the stain, are less well known. This work studies the effect of one component of a leather substrate—quebracho extract—on presumptive and human hemoglobin blood tests. Assays were performed using samples of blood dilutions contaminated with quebracho extract and others formed on a substrate containing the conta…