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1.
Am J Phys Anthropol ; 169(2): 279-286, 2019 06.
Artículo en Inglés | MEDLINE | ID: mdl-30927271

RESUMEN

OBJECTIVES: Estimating the sex of decomposed corpses and skeletal remains of unknown individuals is one of the first steps in the identification process in forensic contexts. Although various studies have considered the femur for sex estimation, the focus has primarily been on a specific single or a handful of measurements rather than the entire shape of the bone. In this article, we use statistical shape modeling (SSM) for sex estimation. We hypothesize that the accuracy of sex estimation will be improved by using the entire shape. MATERIALS AND METHODS: For this study, we acquired a total of 61 femora from routine postmortem CT scans at the Institute for Forensic Medicine of the University of Zurich. The femora were extracted using segmentation technique. After building a SSM, we used the linear regression and nonlinear support vector machine technique for classification. RESULTS: Using linear logistic regression and only the first principal component of the SSM, 76% of the femora were correctly classified by sex. Using the first five principal components, this value could be increased to 80%. Using nonlinear support vector machines and the first 20 principal components increased the rate of correctly classified femora to 87%. DISCUSSION: Despite some limitations, the results obtained by using SSM for sex estimation in femur were promising and confirm the findings of other studies. Sex estimation accuracy, however, is not significantly improved over single or multiple linear measurements. Further research might improve the sex determination process in forensic anthropology by using SSM.


Asunto(s)
Fémur , Procesamiento de Imagen Asistido por Computador/métodos , Modelos Estadísticos , Determinación del Sexo por el Esqueleto/métodos , Tomografía Computarizada por Rayos X/métodos , Adulto , Antropología Física , Femenino , Fémur/anatomía & histología , Fémur/diagnóstico por imagen , Humanos , Masculino
2.
Ophthalmologica ; 231(4): 191-7, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24107451

RESUMEN

Neurotrophic keratitis (NK) is a rare degenerative corneal disease that occurs as a result of partial or total impairment of trigeminal innervations, leading to a reduction (hypoesthesia) in or loss (anaesthesia) of corneal sensitivity. The impairment of sensory innervation causes a reduction in the lacrimation reflex and the vitality, metabolism and mitosis of epithelial cells, with subsequent deficiency in epithelial repair, stromal and intracellular oedema, loss of microvilli, and abnormal development of the basal lamina. Several recent studies have proposed different therapies based on different aetiopathogenetic theories. The aim of the therapy is to treat aetiopathogenesis and, at the same time, promote corneal healing. In this paper, we report the aetiology, diagnosis, management, and medical and surgical treatment of NK, also indicating future treatments based on the most recent studies.


Asunto(s)
Córnea/inervación , Queratitis/etiología , Enfermedades del Nervio Trigémino/complicaciones , Anestesia , Animales , Humanos , Hipoestesia/etiología , Queratitis/diagnóstico , Queratitis/terapia
3.
J Forensic Sci ; 69(1): 9-17, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37855082

RESUMEN

The 1993 US Supreme Court decision Daubert v. Merrell Dow Pharmaceuticals, Inc. presented new guidance for the judicial assessment of expert witness evidence and testimony in the determination of admissibility. Despite the rarity of admissibility challenges to forensic anthropology evidence, Daubert is frequently cited in published forensic anthropology research. This study undertook a qualitative thematic analysis of forensic anthropology articles published in the Journal of Forensic Sciences to assess why authors continue to cite Daubert and express concerns over potential exclusion. The results show a significant increase in the number of articles that cite legal admissibility standards over time (p < 0.001). Authors frequently cite these standards to contextualize their results within the Daubert framework or to justify the need for their research. Notably, many articles present Daubert as a constraining force, misinterpreting the guidelines as rigid criteria or that they require methods to be strictly quantitative. However, Daubert was intended to be a flexible tool for judges-not a standard or instruction for scientists. While it was reasonable to reflect on the scientific rigor of methods in the wake of the Daubert decision, a new perspective is warranted in which forensic anthropologists shift their focus from trying to "satisfy" admissibility guidelines to adopting quality assurance measures that minimize error and ensure confidence in analytical results, and developing and using methods that are grounded in good science-which is important regardless of whether or not the results are ever the subject of a trial.


Asunto(s)
Antropología Forense , Decisiones de la Corte Suprema , Ciencias Forenses , Testimonio de Experto
4.
Int J Immunopathol Pharmacol ; 26(3): 765-8, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-24067474

RESUMEN

The aim of the study is to evaluate the effectiveness and safety of intravitreal infliximab in the course of compassionate use in patients affected by choroidal neovascularization. This prospective interventional case series includes four eligible patients, affected by exudative age-related macular degeneration (2/4), retinal angiomatous proliferation (1/4) and central retinal vein occlusion (1/4), who were refractory to conventional treatments. The patients received a single intravitreal injection of 0.05 ml of reconstituted infliximab solution (20mg/ml). The main outcomes measure were changes in best-corrected visual acuity and central retinal thickness. Patients were evaluated at baseline, every week for the first month, then every two weeks, and on demand. Morphologic parameters improved after a single infliximab intravitreal injection. However, all patients developed acute uveitis in a period ranging from 4 to 7 weeks after treatment. Control of the intraocular inflammation was achieved with topical and systemic steroids in 3 patients, whereas in one case pars plana vitrectomy was needed. A single intravitreal injection of infliximab does not seem to improve the natural history of CNV from different aetiologies. However, all patients in our series developed a serious inflammatory response that required surgical management in one case. The intravitreal administration of infliximab is hence not safe and not recommended in clinical practice.


Asunto(s)
Antiinflamatorios/administración & dosificación , Anticuerpos Monoclonales/administración & dosificación , Neovascularización Coroidal/tratamiento farmacológico , Anciano , Anciano de 80 o más Años , Antiinflamatorios/efectos adversos , Anticuerpos Monoclonales/efectos adversos , Neovascularización Coroidal/diagnóstico , Neovascularización Coroidal/fisiopatología , Ensayos de Uso Compasivo , Femenino , Humanos , Infliximab , Inyecciones Intravítreas , Degeneración Macular/complicaciones , Masculino , Estudios Prospectivos , Retina/efectos de los fármacos , Retina/patología , Oclusión de la Vena Retiniana/complicaciones , Esteroides/administración & dosificación , Factores de Tiempo , Resultado del Tratamiento , Uveítis/inducido químicamente , Uveítis/diagnóstico , Uveítis/terapia , Agudeza Visual/efectos de los fármacos , Vitrectomía , Enfermedad de von Hippel-Lindau/complicaciones
5.
Forensic Sci Int ; 332: 111196, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-35123259

RESUMEN

OBJECTIVES: Due to taphonomic processes such as burial, fire, or animal activity, bones are often found incomplete, which can pose problematic for establishing the biological profile of the deceased using anthropological methods. The aim of this study is to test the feasibility of using statistical shape modeling (SSM) to reconstruct full femora from simulated partial femora and determine the accuracy of the reconstruction. Moreover, we assess the accuracy of sex estimation and the degree of stature error added based on the reconstructed femur using different anthropological methods. METHODS: A total of 42 (28 female, 14 female) 3D models of left femora extracted from computed tomography (CT) scans were used. We performed a leave-one-out cross-validation (LOOCV) where 41 bones were used to build the SSM and one bone was used for testing. This bone was cut in 1 cm steps proximally, distally and from both ends up to 10 cm, reconstructed using SSM, and tested using the methods established by Stewart and Purkait (2005), Trotter and Gleser (1952), as well as a method based on SSM. with landmarks being automatically identified. RESULTS: The error induced by reconstructing the femur to the length measurements was low, which translated into useful stature estimations (single sided cuts up to 10 cm: 0.4-1.1%, double sided<2% for cuts shorter than 6 cm). Using Purkaits method for sex estimation on reconstructed bones looked promising as well (single sided: 90.5% when compared to applying Purkaits method on the original bone, double sided 78.6% (10 cm cut) to 97.6% (1-3 cm cuts)) Using SSM for sex classification looked promising as well (single sided cut: 81-85.7%, double sided cut: 59.5-85.3%) CONCLUSION: SSM can be used to reconstruct fragmented femora. These reconstructions can be used for sex and stature estimations, at the cost of lower accuracy. Using SSM might give investigators an additional tool to gain information about the biological profile of a deceased in cases where the fragmentation of a femur does not allow for using other anthropological methods.

6.
Am J Physiol Cell Physiol ; 301(4): C833-40, 2011 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-21734189

RESUMEN

Using split cardiac Na(+)/Ca(2+) exchangers (NCX1), we previously demonstrated that phospholemman (PLM) regulates NCX1 by interacting with the proximal linker domain (residues 218-358) of the intracellular loop of NCX1. With the use of overlapping loop deletion mutants, interaction sites are localized to two regions spanning residues 238-270 and residues 300-328 of NCX1. In this study, we used alanine (Ala) linker scanning to pinpoint the residues in the proximal linker domain involved in regulation of NCX1 by PLM. Transfection of human embryonic kidney (HEK)293 cells with wild-type (WT) NCX1 or its Ala mutants but not empty vector resulted in NCX1 current (I(NaCa)). Coexpression of PLM with WT NCX1 inhibited I(NaCa). Mutating residues 248-252 (PASKT) or 300-304 (QKHPD) in WT NCX1 to Ala resulted in loss of inhibition of I(NaCa) by PLM. By contrast, inhibition of I(NaCa) by PLM was preserved when residues 238-242, 243-247, 253-257, 258-262, 263-267, 305-309, 310-314, 315-319, 320-324, or 325-329 were mutated to Ala. While mutating residue 301 to alanine completely abolished PLM inhibition, mutation of any single residue 250-252, 300, or 302-304 resulted in partial reduction in inhibition. Mutating residues 248-252 to Ala resulted in significantly weaker association with PLM. The NCX1-G503P mutant that lacks Ca(2+)-dependent activation retained its sensitivity to PLM. We conclude that residues 248-252 and 300-304 in the proximal linker domain of NCX1 were involved in its inhibition by PLM.


Asunto(s)
Regulación de la Expresión Génica/fisiología , Proteínas de la Membrana/metabolismo , Fosfoproteínas/metabolismo , Intercambiador de Sodio-Calcio/química , Intercambiador de Sodio-Calcio/metabolismo , Alanina/química , Secuencia de Aminoácidos , Animales , Células HEK293 , Humanos , Datos de Secuencia Molecular , Mutación , Estructura Terciaria de Proteína , Ratas , Intercambiador de Sodio-Calcio/genética
7.
Forensic Sci Int ; 329: 111091, 2021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-34773818

RESUMEN

A routine geologic test for the presence of carbonate minerals in soil is the application of dilute hydrochloric acid (HCl) and observation for an effervescent reaction. This study tests whether non-carbonate soils can exhibit effervescence in the presence of HCl if bone particles are present in the soil. Five bone fragments displaying various taphonomic alterations were ground and sieved to achieve uniform particle size fractions. A non-carbonate soil was mixed with each bone particle fraction, and 1 molar HCl solution was applied while observing the reaction using a stereo microscope. All tests resulted in the effervescence of bone particles, which could be easily located within the soil based on the presence of small bubbles surrounding the bone particle. These results show that a simple, quick, cost-effective test can be used to presumptively determine whether soil may contain bone particles, even if they are too small to be identified morphologically. Results also suggest that, since bone particles in soil can produce the same type of effervescence expected in carbonate soil, additional tests may be needed to determine the source of an effervescent reaction. These findings also highlight the insight that can be gained through interdisciplinary discussions and investigations.


Asunto(s)
Ácido Clorhídrico , Suelo , Carbonatos , Tamaño de la Partícula
9.
J Forensic Sci ; 64(1): 186-189, 2019 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-29975981

RESUMEN

Commingling is frequently encountered in cases examined by the Committee on Missing Persons in Cyprus, and pair-matching is routinely used as a preliminary segregation method. Here we examine the degree of bilateral asymmetry in nutrient foramen position of the radius and ulna to determine whether nutrient foramen position may be useful in visual and/or ostetometric pair-matching. Differences in nutrient foramen position between left-right pairs from the same individual were compared with differences in nutrient foramen position between different individuals. Bilateral asymmetry in nutrient foramen position was found to be high, indicating that it is not a reliable trait for pair-matching. Bilateral asymmetry and between-person variation were found to differ between the two bones examined, suggesting that nutrient foramen position in other long bones should also be tested.


Asunto(s)
Osteón/anatomía & histología , Radio (Anatomía)/anatomía & histología , Cúbito/anatomía & histología , Población Negra , Femenino , Antropología Forense/métodos , Humanos , Masculino , Población Blanca
10.
J Forensic Sci ; 64(4): 1135-1138, 2019 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-30735574

RESUMEN

Thermally altered skeletal remains can be very fragile and fragmented and are typically further fragmented or even destroyed when handled; recovery of such remains from a scene can therefore be extremely challenging. There are few recommendations and no generally accepted practices for preserving burned bone for recovery and transport. Here, we test whether the application of a gelatin-based consolidant at the scene can preserve thermally altered bone in the condition and relative anatomical position in which it was discovered. A solution of Knox® brand gelatin and water was applied to burned pig mandibles using a spray bottle. Qualitative and quantitative analysis indicates that the application of the consolidant significantly decreased fragmentation as compared to untreated controls (p < 0.05), with most of the treated mandibles remaining completely intact after recovery and transport to a secondary location. In addition to the effectiveness for preservation, the method is also easy to apply, inexpensive, and reversible.


Asunto(s)
Restos Mortales , Incendios , Antropología Forense/métodos , Gelatina , Manejo de Especímenes/métodos , Animales , Quemaduras , Mandíbula , Modelos Animales , Porcinos
11.
J Forensic Sci ; 64(3): 869-872, 2019 May.
Artículo en Inglés | MEDLINE | ID: mdl-30248185

RESUMEN

This study tests the effect of three common oxidizing cleaners on the ability of the Bluestar Forensic® presumptive test for blood to identify the presence of blood on ceramic tile after cleaning. The cleaners tested were Lysol®, OxiClean®, and Arm & Hammer®. This study also tested which cleaner was the most effective at removing blood, measured by the intensity of chemiluminescence, which was quantified using RGB values in ImageJ. A "hasty" 1-min cleaning of a blood droplet was simulated using the three cleaners. The chemiluminescence of the Bluestar® reactions after cleaning the blood-treated region was compared to an untreated region of the same tile for each cleaner, as well as to the treated regions of tiles between the three cleaners. Results indicate that none of the three cleaners removed all of the blood (all p < 0.001) and that Lysol® removed more blood compared to the OxiClean® and Arm & Hammer®.


Asunto(s)
Manchas de Sangre , Detergentes , Productos Domésticos , Luminiscencia , Sustancias Luminiscentes , Medicina Legal , Humanos , Indicadores y Reactivos
12.
J Forensic Sci ; 53(3): 694-8, 2008 May.
Artículo en Inglés | MEDLINE | ID: mdl-18471217

RESUMEN

The following study examines the reliability of physically matching fragments of bone and other mineral-based biological materials such as shells and teeth. Participants with varying education, training, and experience were asked to complete a matching exercise consisting of intentionally fragmented specimens. Success rates were very high; the positive association (correct match) rate was 0.925, while the nonassociation (overlooked match) rate was 0.075, and negative associations (incorrect matches) occurred at a rate of just 0.001. Results also indicate that those with more education and related experience tended to have higher positive association rates, although not significant statistically. Experienced osteologists, however, completed the matching exercise in significantly less time. Low error rates among both experienced and inexperienced individuals support the reliability and validity of performing physical matches of these materials, and suggest that performance may also be related to an individual's aptitude for spatial tasks or other factors.


Asunto(s)
Huesos/patología , Cáscara de Huevo/patología , Antropología Forense , Diente/patología , Animales , Escolaridad , Humanos , Competencia Profesional , Factores de Tiempo
13.
Eur J Ophthalmol ; 17(3): 441-4, 2007.
Artículo en Inglés | MEDLINE | ID: mdl-17534832

RESUMEN

PURPOSE: To describe the efficacy of MP-1 in detecting early multiple sclerosis (MS) retinal lesions and in monitoring the effectiveness of treatment in terms of changes in macular sensitivity. METHODS: A 21-year-old woman with MS was referred to us complaining of recurrent episodes of eyesight loss in both eyes. At ophthalmologic examination, best-corrected visual acuity was 20/25 bilaterally; ophthalmoscopy showed bilateral slight optic neuritis without swelling of the disc. Static perimetry of central visual field (30 degrees, by Octopus 101, Haag-Streit AG, Switzerland) and retinal sensitivity of the 12 central degrees (by MP-1 Micro Perimeter, Nidek Inc., Italy) were performed on the patient at that time. The micro perimeter (MP-1) showed a loss of sensitivity in the macular region with 0.28+/-0.9 dB sensitivity in the right eye and 19.42+/1.5 dB in the left. The mean fixation stability was 91% considering 2 degrees and 99% considering 4 degrees around the fixation points in the right eye, and 97% in 2 degrees and 100% in 4 degrees central degrees in the left. In the weeks that followed vision continued to get worse in both eyes, so she underwent a steroid therapy with methylprednisolone IV 1000 mg/day for 5 days and 500 mg/day for 3 days. RESULTS: After 8 days of therapy the MP-1 showed a significant recovery in the right eye, with mean light sensitivity being 19.61+/-1.3 dB in the right eye and 20.0+/-0 dB in the left eye in both macular and peripapillary regions. The mean fixation stability was 100% considering 2 degrees and 100% considering 4 degrees around the fixation points in both eyes. CONCLUSIONS: The MP-1 can be an interesting tool for neuro-ophthalmologists as it allows a more precise evaluation of the macular and peripapillary region, which is not easily studied with conventional automated perimetry. In MS, the presence of a subclinical form of optic nerve involvement can be demonstrated in a very early stage, and well followed by the introduction of micro perimeter testing in the standard examination protocol.


Asunto(s)
Esclerosis Múltiple/diagnóstico , Neuritis Óptica/diagnóstico , Enfermedades de la Retina/diagnóstico , Trastornos de la Visión/diagnóstico , Pruebas del Campo Visual/métodos , Campos Visuales , Adulto , Femenino , Glucocorticoides/uso terapéutico , Humanos , Metilprednisolona/uso terapéutico , Esclerosis Múltiple/tratamiento farmacológico , Esclerosis Múltiple/fisiopatología , Neuritis Óptica/tratamiento farmacológico , Neuritis Óptica/fisiopatología , Enfermedades de la Retina/tratamiento farmacológico , Enfermedades de la Retina/fisiopatología , Trastornos de la Visión/tratamiento farmacológico , Trastornos de la Visión/fisiopatología
14.
Forensic Sci Int ; 270: 70-75, 2017 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-27915189

RESUMEN

Citrate content in bone has been shown to be associated with the postmortem interval (PMI), with citrate decreasing after death as a function of time. Here we test this method using porcine ribs for the period of 1-165days after death, and also assess citrate content and variation from samples placed into two different postmortem environments (terrestrial and aquatic). Higher citrate variation, lower citrate recovery, and a weaker association with time were found in this study as compared to others. Citrate content, however, was found to decrease with increasing PMI, and the method was found to be easy and inexpensive to apply. No significant differences were found in citrate loss between terrestrial and aquatic environments. Although more research is needed, citrate content appears to be a promising new approach in estimating PMI from skeletal remains.


Asunto(s)
Ácido Cítrico/análisis , Cambios Post Mortem , Costillas/química , Animales , Restos Mortales , Modelos Animales , Reproducibilidad de los Resultados , Porcinos
15.
Forensic Sci Int ; 280: 81-86, 2017 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-28961444

RESUMEN

The aim of this study was to assess the reproducibility of a standardized image for personal identification (SIPI), used in the comparative analysis of paranasal sinuses, and test the effect of inaccurate reformation of the SIPI on suitability for comparative identification. Five raters with different professional backgrounds independently reformatted SIPIs from ten post-mortem head CTs. Inter-rater, intra-rater agreement as well angular deviations between reformatted SIPI images and reference SIPI images were calculated. Second, raters assessed the suitability of 70 accurately and inaccurately reformatted SIPIs for identification with a 4-point Likert scale. Inter-rater agreement as well as levels of significance regarding image suitability were calculated. Inter-rater agreement regarding reproducibility of SIPI reformation was excellent (inter-rater correlation coefficient (ICC) 0.9995, intra-rater ICC 0.9983). Deviation between the angular dimensions of the reformatted SIPIs and the reference SIPIs was ≤1° in 94% of all 300 measurements. Inter-rater agreement regarding the effect of inaccurate SIPI reformation on suitability for comparative identification was fair (ICC 0.6809). There was no statistically significant difference between raters' evaluation of image suitability (p=0.9755). This study shows that the standardized image for personal identification can be accurately reformatted by different raters with varying professional backgrounds. In addition, raters agree that inaccurately reformatted SIPIs are still suitable for comparative identification in the majority of cases.


Asunto(s)
Identificación Biométrica/métodos , Senos Paranasales/diagnóstico por imagen , Tomografía Computarizada por Rayos X , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Persona de Mediana Edad , Variaciones Dependientes del Observador , Senos Paranasales/anatomía & histología , Reproducibilidad de los Resultados
16.
J Forensic Sci ; 61(2): 439-441, 2016 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-27404616

RESUMEN

Burned skeletal material is often very fragile and at high risk for fragmentation during packaging and transportation. One method that has been suggested to protect bones in these cases is to carefully wrap them in aluminum foil. Traces of aluminum, however, are known to transfer from foil packaging materials to food products. If such transfer occurs between aluminum foil and bones, it could interfere with subsequent chemical, elemental and isotopic analyses, which are becoming more common in forensic anthropological investigations. This study examined aluminum levels in bones prior to and following the use of aluminum foil packaging and storage for a 6-week period. Results indicate no significant change in the detected levels of aluminum (p > 0.05), even when packaged in compromised foil and exposed to elevated temperatures. Aluminum foil can therefore continue to be recommended as a packaging medium without affecting subsequent chemical examinations.


Asunto(s)
Aluminio/análisis , Huesos/química , Huesos/patología , Manejo de Especímenes/instrumentación , Animales , Quemaduras , Ciervos , Incendios , Antropología Forense , Manejo de Especímenes/métodos , Espectrometría de Fluorescencia
17.
J Forensic Sci ; 61(2): 442-444, 2016 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-27404617

RESUMEN

Bones fluoresce when exposed to certain wavelengths of shortwave light, and this property can be useful in locating and sorting skeletal remains in forensic contexts. The proteins in bone collagen are largely responsible for its fluorescent properties, but these proteins degrade and denature over time. This study examined the fluorescence of bones from four temporal groups (recent, semi-recent, ancient, and historic) ranging from 0 to 1064 years before present. Specimens were photographed under 490 nm wavelength light, and fluorescence was quantified by converting intensity to a gray scale value based on the RGB color model using ImageJ(®) software. Significant (p < 0.05) differences were found in mean fluorescence between all four temporal groups, and a 0.324 coefficient of correlation indicates a significant (inverse) relationship between fluorescence and time. Bone fluorescence decreases with time, but some fluorescence is retained even in older samples. Fluorescence can therefore be reliably used in many modern skeletal remains searches.


Asunto(s)
Huesos/química , Fluorescencia , Animales , Antropología Forense , Historia del Siglo XIX , Historia Antigua , Humanos , Luz , Porcinos , Factores de Tiempo
18.
J Forensic Sci ; 61 Suppl 1: S190-2, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26375756

RESUMEN

Elemental analysis of calcium (Ca) and phosphorus (P) has been shown to be useful in differentiating skeletal and nonskeletal material. X-ray fluorescence spectrometry (XRF) is an attractive, nondestructive technique for forensic anthropologists, and the development of portable XRF instrumentation is promising for field applications. This study examines the performance of handheld XRF instrumentation operated in air compared to a traditional benchtop XRF device that has the ability to control the analysis atmosphere. Both instruments can be used to effectively distinguish skeletal from nonskeletal remains. However, as the measurement atmosphere affects detection levels for calcium and phosphorus, Ca/P ratios obtained from the instruments and analysis conditions were found to differ significantly, with analyses conducted in air showing significantly lower phosphorus detection. Consequently, comparison of Ca/P ratios to conclude skeletal versus nonskeletal origin must be based on data collected under similar analysis conditions.


Asunto(s)
Calcio/análisis , Fósforo/análisis , Huesos , Humanos , Radiografía , Espectrometría por Rayos X , Rayos X
19.
J Forensic Sci ; 50(1): 18-22, 2005 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-15830992

RESUMEN

The use of frontal sinus radiographs in positive identification has become an increasingly applied and accepted technique among forensic anthropologists, radiologists, and pathologists. From an evidentiary standpoint, however, it is important to know whether frontal sinus radiographs are a reliable method for confirming or rejecting an identification, and standardized methods should be applied when making comparisons. The purpose of the following study is to develop an objective, standardized comparison method, and investigate the reliability of that method. Elliptic Fourier analysis (EFA) was used to assess the variation in 808 outlines of frontal sinuses by calculating likelihood ratios and posterior probabilities from EFA coefficients. Results show that using EFA coefficient comparison to estimate the probability of a correct identification is a reliable technique, and EFA comparison of frontal sinus outlines is recommended when it may be necessary to provide quantitative substantiation for a forensic identification based on these structures.


Asunto(s)
Antropología Forense/métodos , Seno Frontal/anatomía & histología , Antropometría , Análisis de Fourier , Humanos , Valores de Referencia , Reproducibilidad de los Resultados
20.
J Forensic Sci ; 60(4): 974-8, 2015 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-25762496

RESUMEN

Analyzing and identifying skeletal remains becomes increasingly difficult when remains have been cremated, especially in cases where the cremated material may have been intentionally contaminated with nonskeletal material. This study examined the potential of X-ray fluorescence spectrometry (XRF) to detect the presence of nonskeletal contaminants in samples of cremains. Eleven samples of cremains were variably combined with concrete mix and analyzed using XRF. Photon counts of elements in each sample were analyzed, and the coefficient of determination (R(2)) using unweighted linear regression as a function of percent cremains was calculated. Results showed that with changes in the proportion of skeletal material and contaminant, there were significant (R(2) > 0.90) changes in detected levels of phosphorus, potassium, zinc, aluminum, and sulfur. The use of XRF is concluded to be a valid approach in the identification of the presence of nonskeletal material in potentially contaminated cremains.


Asunto(s)
Cremación , Espectrometría por Rayos X , Aluminio/análisis , Calcio/análisis , Ciencias Forenses , Humanos , Modelos Lineales , Fósforo/análisis , Potasio/análisis , Azufre/análisis , Zinc/análisis
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