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1.
Curr Pain Headache Rep ; 28(7): 627-632, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38367200

RESUMO

PURPOSE OF REVIEW: This review summarizes the evolution in diagnosis, evaluation, and treatment of primary headache associated with sexual activity (PHASA). RECENT FINDINGS: Despite increased access to patient information and advances in imaging, the pathophysiology of PHASA remains not fully understood. There are many secondary headaches that may present with headache during sexual activity, and a thorough workup is indicated to rule out potentially life-threatening etiologies. Many recent case series discuss the efficacy of known treatments of PHASA, as well as suggest other potential therapies for this condition including the newer CGRP-targeted therapies. Headaches during sexual activity can be worrisome events which necessitate urgent evaluation, particularly when presenting with sudden-onset and severe "thunderclap" headaches. A thorough workup including imaging should be conducted to rule out etiologies such as subarachnoid hemorrhage, reversible cerebral vasoconstrictive syndrome (RCVS), vasospasm, and dissection. PHASA is commonly comorbid with migraine, tension-type headache, exertional headache, and hypertension. PHASA can present as a dull headache that progresses with sexual excitement, or an explosive headache at or around orgasm. Pain is primarily occipital, diffuse, and bilateral. The headaches are discrete, recurrent events with bouts that typically self-resolve, but may also relapse and remit or continue chronically in some patients. PHASA can be treated preemptively with indomethacin and triptans administered prior to sexual activity, or treated prophylactically with beta-blockers, topiramate, and calcium channel blockers. CGRP-targeted therapies may provide relief in PHASA based on a few case reports, but there are no randomized controlled trials looking at specific efficacy for these therapies.


Assuntos
Comportamento Sexual , Humanos , Comportamento Sexual/fisiologia , Transtornos da Cefaleia Primários/fisiopatologia , Transtornos da Cefaleia Primários/tratamento farmacológico , Transtornos da Cefaleia Primários/diagnóstico , Cefaleia/fisiopatologia
2.
Sci Justice ; 54(5): 335-7, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25278194

RESUMO

The underlying principles involved in the interpretation of shoeprint comparisons have become a topical subject due to criticisms in the 2009 National Academy of Science (NAS) report on forensic sciences[1]. Difficulties in the application and understanding of these principles were also highlighted in a recent court ruling [2-5] and subsequent discussion of the ruling. We report here a survey that may inform some aspects of this interpretation and discuss the implications of findings from this survey in the light of that court ruling and more importantly the NAS report. 1,511 shoeprints were taken from student volunteers in Auckland, Wellington and Dunedin, New Zealand. 500 shoeprints were sampled from student volunteers at Australian universities. 100 from each of the University of Technology in Sydney, University of Queensland in Brisbane, University of Newcastle, Charles Sturt University in Bathurst and University of Canberra, Australia. These cities are distributed along the east coast of Australia. The shoeprints, taken from each country, were compared against each other for the presence of any pattern correspondences However shoeprints have not been compared between countries. In all locations the pattern of some common and many rare outsole patterns was repeated, with Converse Chuck Taylor All Stars and Vans Canvas Era common in all locations.

3.
Transl Anim Sci ; 5(4): txab205, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34761168

RESUMO

A total of 1,215 pigs (L337 × 1050, PIC, Hendersonville, TN) were used to determine the effect of microencapsulated organic acids and botanicals (MOB; AviPlus; Vetagro, Inc. Chicago, IL), on growth performance from weaning to market. Pigs were weaned at approximately 21 d of age and placed in pens based on initial body weight (BW) with 27 pigs per pen in a randomized complete block design. During the 42-d nursery period, pigs were allotted to one of two treatments in an unbalanced treatment structure with 15 pens (replications) fed the control diet and 30 pens (replications) fed diets containing 0.30% MOB from days 0 to 21 and 0.10% from days 21 to 42. On day 42, pigs were transported as intact pens from the nursery to the finishing facility. During the finishing period, three treatments were applied which included: 1) pigs on the control diet in nursery remained on control diets; 2) 50% of pigs provided MOB in nursery were then fed 0.05% MOB throughout finishing, and 3) 50% of pigs provided MOB in nursery were then fed the control diet throughout finishing. All pens of pigs on treatments 2 and 3 were allotted based on ending nursery BW to the finishing treatment. There were 15 replications per treatment in the finishing period. From days 0 to 21, pigs fed diets with MOB had a tendency for increased (P < 0.058) gain:feed (G:F) when compared to pigs fed the control diet; however, there was no evidence of difference (P > 0.05) for average daily gain (ADG), average daily feed intake (ADFI), or day 21 BW. From days 21 to 42, there was no evidence of difference (P > 0.05) for ADG, ADFI, or G:F. For the overall nursery period (days 0 to 42), pigs fed diets with MOB had increased (P < 0.05) G:F (660 vs. 670 g/kg) when compared with pigs fed the control diet, but there was no evidence of difference (P > 0.05) for day 42 BW, ADG, or ADFI between treatments. From d 42 to 106, there was no evidence of difference (P > 0.05) for ADG, ADFI, and G:F. For the overall finishing period (days 42 to 156) and overall experimental period (days 0 to 156), there was no evidence of difference (P > 0.05) for BW, ADG, ADFI, or G:F. For mortality and removals, there was no evidence of difference (P > 0.05) observed during the nursery, finishing, or overall. In summary, providing MOB during the nursery phase increased G:F in the early and overall nursery phase, but there was no effect on overall wean-to-finish performance.

4.
Sci Justice ; 49(2): 73-80, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19606584

RESUMO

An evaluation was undertaken to determine if isotope ratio mass spectrometry (IRMS) could assist in the investigation of complex forensic cases by providing a level of discrimination not achievable utilising traditional forensic techniques. The focus of the research was on ammonium nitrate (AN), a common oxidiser used in improvised explosive mixtures. The potential value of IRMS to attribute Australian AN samples to the manufacturing source was demonstrated through the development of a preliminary AN classification scheme based on nitrogen isotopes. Although the discrimination utilising nitrogen isotopes alone was limited and only relevant to samples from the three Australian manufacturers during the evaluated time period, the classification scheme has potential as an investigative aid. Combining oxygen and hydrogen stable isotope values permitted the differentiation of AN prills from three different Australian manufacturers. Samples from five different overseas sources could be differentiated utilising a combination of the nitrogen, oxygen and hydrogen isotope values. Limited differentiation between Australian and overseas prills was achieved for the samples analysed. The comparison of nitrogen isotope values from intact AN prill samples with those from post-blast AN prill residues highlighted that the nitrogen isotopic composition of the prills was not maintained post-blast; hence, limiting the technique to analysis of un-reacted explosive material.


Assuntos
Substâncias Explosivas/química , Ciências Forenses/métodos , Espectrometria de Massas/métodos , Hidrogênio/análise , Espectrometria de Massas/instrumentação , Nitratos/análise , Isótopos de Nitrogênio/análise , Isótopos de Oxigênio/análise
5.
Sci Justice ; 49(2): 81-6, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19606585

RESUMO

The application of isotopic techniques to investigations requiring the provision of evidence to a Court is limited. The objective of this research was to investigate the application of light stable isotopes and isotope ratio mass spectrometry (IRMS) to solve complex forensic cases by providing a level of discrimination not achievable utilising traditional forensic techniques. Due to the current threat of organic peroxide explosives, such as triacetone triperoxide (TATP), research was undertaken to determine the potential of IRMS to differentiate samples of TATP that had been manufactured utilising different starting materials and/or manufacturing processes. In addition, due to the prevalence of pentaerythritoltetranitrate (PETN) in detonators, detonating cord, and boosters, the potential of the IRMS technique to differentiate PETN samples from different sources was also investigated. Carbon isotope values were measured in fourteen TATP samples, with three definite groups appearing in the initial sample set based on the carbon data alone. Four additional TATP samples (in a second set of samples) were distinguishable utilising the carbon and hydrogen isotopic compositions individually, and also in combination with the oxygen isotope values. The 3D plot of the carbon, oxygen and hydrogen data demonstrated the clear discrimination of the four samples of TATP. The carbon and nitrogen isotope values measured from fifteen PETN samples, allowed samples from different sources to be readily discriminated. This paper demonstrates the successful application of IRMS to the analysis of explosives of forensic interest to assist in discriminating samples from different sources. This research represents a preliminary evaluation of the IRMS technique for the measurement of stable isotope values in TATP and PETN samples, and supports the dedication of resources for a full evaluation of this application in order to achieve Court reportable IRMS results.


Assuntos
Substâncias Explosivas/química , Ciências Forenses/métodos , Compostos Heterocíclicos com 1 Anel/química , Espectrometria de Massas/métodos , Tetranitrato de Pentaeritritol/química , Peróxidos/química , Isótopos de Carbono/análise , Hidrogênio/análise , Isótopos de Oxigênio/análise
6.
Forensic Sci Int ; 303: 109953, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31546168

RESUMO

Ignitable liquid detection dogs have been observed to falsely-respond to the pyrolysis products of common burned household items such as carpets and garden hoses, where ignitable liquids were not present. These responses from the canines are described as coming from distractor odours and decrease the reliability of detector dogs. The purpose of this research was to study the volatile organic compounds (VOCs) present in the odour profile of pyrolysed carpet and garden hose substrates, and determine whether a chemical similarity exists between these pyrolysis headspace profiles and target ignitable liquids, which may explain the false-positive behaviour of these detector dogs. Garden hose and carpet samples obtained from domestic settings were heated at a constant temperature for a specified time to produce pyrolysis products. A solid-phase microextraction (SPME) method was developed to extract the VOCs from burned substrates. The odours of the burned substrates were analysed by gas chromatography-mass spectrometry (GC/MS) and gas chromatography-tandem mass spectrometry (GC/MS/MS). A GC-MS/MS method was developed targeting the characteristic aromatic compounds in gasoline. Each pyrolysed substrate produced a complex and unresolved odour profile when analysed by GC- MS. GC-MS analysis failed to find any similarities between the odours of the burned substrates and ignitable liquids. GC-MS/MS analysis of pyrolysed garden hose and carpet substrate odours resolved and identified a wide range of aromatic target compounds - and these were present in high abundances in the hose samples. This indicates that there are significant chemical similarities between vapours of ignitable liquids and their distractor odours, which will have implications for the training of ignitable liquid detector dogs.


Assuntos
Cães/fisiologia , Incêndios , Odorantes , Olfato/fisiologia , Compostos Orgânicos Voláteis/análise , Animais , Ciências Forenses , Cromatografia Gasosa-Espectrometria de Massas
7.
Forensic Sci Int ; 296: 57-66, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30690252

RESUMO

Following the technological rise of surveillance cameras and their subsequent proliferation in public places, the use of information gathered by such means for investigative and evaluative purposes sparked a large interest in the forensic community and within policing scenarios. In particular, it is suggested that analysis of the body, especially the assessment of gait characteristics, can provide useful information to aid the investigation. This paper discusses the influences upon gait to mitigate some of the limitations of surveillance footage, including those due to the varying anatomical differences between individuals. Furthermore, the differences between various techniques applied to assess gait are discussed, including biometric gait recognition, forensic gait analysis, tracking technology, and marker technology. This review article discusses the limitations of the current methods for assessment of gait; exposing gaps within the literature in regard to various influences impacting upon the gait cycle. Furthermore, it suggests a 'morphometric' technique to enhance the available procedures to potentially facilitate the development of standardised protocols with supporting statistics and database. This in turn will provide meaningful information to forensic investigation, intelligence-gathering processes, and potentially as an additional method of forensic evaluation of evidence.


Assuntos
Identificação Biométrica/métodos , Ciências Forenses/métodos , Análise da Marcha , Gravação em Vídeo , Ciências Forenses/legislação & jurisprudência , Humanos , Processamento de Imagem Assistida por Computador , Extremidade Inferior/anatomia & histologia , Extremidade Inferior/fisiologia
8.
Forensic Sci Int ; 285: 77-85, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29453008

RESUMO

As a result of the worldwide deployment of surveillance cameras, authorities have gained a powerful tool that captures footage of activities of people in public areas. Surveillance cameras allow continuous monitoring of the area and allow footage to be obtained for later use, if a criminal or other act of interest occurs. Following this, a forensic practitioner, or expert witness can be required to analyse the footage of the Person of Interest. The examination ultimately aims at evaluating the strength of evidence at source and activity levels. In this paper, both source and activity levels are inferred from the trace, obtained in the form of CCTV footage. The source level alludes to features observed within the anatomy and gait of an individual, whilst the activity level relates to activity undertaken by the individual within the footage. The strength of evidence depends on the value of the information recorded, where the activity level is robust, yet source level requires further development. It is therefore suggested that the camera and the associated distortions should be assessed first and foremost and, where possible, quantified, to determine the level of each type of distortion present within the footage. A review of the 'forensic image analysis' review is presented here. It will outline the image distortion types and detail the limitations of differing surveillance camera systems. The aim is to highlight various types of distortion present particularly from surveillance footage, as well as address gaps in current literature in relation to assessment of CCTV distortions in tandem with gait analysis. Future work will consider the anatomical assessment from surveillance footage.


Assuntos
Artefatos , Identificação Biométrica , Gravação em Vídeo , Ciências Forenses/legislação & jurisprudência , Humanos , Medidas de Segurança
9.
J Forensic Sci ; 52(4): 938-42, 2007 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-17553086

RESUMO

The unusual appearance of crystalline fat structures was observed during the postmortem examination of a motor vehicle accident victim. The crystal structures were characterized using Fourier transform infrared spectroscopy and x-ray diffractometry. The structures were found to be made of triacylglycerols, a dominant lipid structure found in human adipose tissue, capable of forming various polymorphic structures. The morphology of the crystalline material was found using both techniques to be predominantly the beta' form of triacylglycerols. The accelerated growth of such triacylglycerol morphology has been observed as a result of shear stresses in other studies involving edible fats. As a result of the findings of this study, it is proposed that increased shear forces may be responsible for the formation of the unusual fat structure found in the victim. An understanding of the effect of forces on the structure of body fat in high-impact collisions can potentially assist in verifying a high-velocity impact.


Assuntos
Tecido Adiposo/química , Veículos Automotores , Triglicerídeos/química , Adulto , Autopsia/métodos , Patologia Legal/métodos , Humanos , Masculino , Espectroscopia de Infravermelho com Transformada de Fourier , Difração de Raios X
11.
Forensic Sci Int ; 157(1): 1-22, 2006 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-15919168

RESUMO

The key role of a forensic scientist is to assist in determining whether a crime has been committed, and if so, assist in the identification of the offender. Many people hold the belief that a particular item can be conclusively linked to a specific person, place or object. Unfortunately, this is often not achievable in forensic science. In performing their role, scientists develop and test hypotheses. The significance of those hypotheses that cannot be rejected upon completion of all available examinations/analyses is then evaluated. Although one can generally identify the substances present using available techniques, it is generally not possible to distinguish one source of the same substance from another. In such circumstances, although a particular hypothesis cannot be rejected, it cannot be conclusively proven, i.e. the samples could still have originated from different sources. This limitation of not being able to distinguish between sources currently extends to the analysis of other forensic samples including, but not limited to, ignitable liquids, paints, adhesives, textile fibres, plastics, and illicit drugs. Stable isotope ratio mass spectrometry (IRMS) is an additional technique that can be utilised to test a given hypothesis. This technique shows the potential to be able to individualise a range of materials of forensic interest. This paper provides a brief description of the technique, followed by a review of the various applications of IRMS in different scientific fields. The focus of this summary is on forensic applications of IRMS, in particular the analysis of explosives, ignitable liquids and illicit drugs.


Assuntos
Medicina Legal , Espectrometria de Massas/métodos , Animais , Arqueologia , Dopagem Esportivo , Poluentes Ambientais/análise , Explosões , Análise de Alimentos , Humanos , Isótopos/análise , Espectrometria de Massas/instrumentação , Preparações Farmacêuticas/química , Fenômenos Fisiológicos Vegetais , Controle de Qualidade , Especificidade da Espécie , Detecção do Abuso de Substâncias/métodos
12.
Forensic Sci Int ; 248: 124-8, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25612880

RESUMO

The interpretation of vehicle paint traces in forensic casework hinges on a number of factors including the type of paint, colour, number of layers, and background information. Vehicle colour surveys are an important source of information for the forensic paint examiner when interpreting the level of significance of a paint transfer between vehicles involved in a collision, or smears of vehicle paint left at a scene. The two surveys that are presented here investigated (i) the frequency of the colour of vehicles observed on both a motorway and suburban roads in Western Sydney and (ii) the frequency of different vehicle paint colours transferred to car park pillars and walls from five different car parks within North West Sydney, Australia. In the first survey, the highest frequency of vehicle colours recorded was white, grey, black and blue. The second survey resulted in very similar findings with the four most commonly seen colours across the five car parks being blue, white, red, and silver. The results in the second survey take into account the potential for anomalies within the data due to the use of painted service vehicles used within the car parks, such as trolleys and trailers. The results from both surveys were very similar to previous vehicle colour surveys that have been conducted and also corresponded to the vehicle colour registration data obtained from the NSW Roads and Maritime Service website. The results from these two surveys provide up to date statistics that can assist the forensic paint examiner with valuable background data when assessing the significance of vehicle paint evidence in casework.

13.
Forensic Sci Int ; 135(2): 137-45, 2003 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-12927415

RESUMO

The Maxcan fibre finder system is a product of Cox Analytical Systems, Sweden, and has been developed for the primary purpose of searching for fibres on tape lifts. This paper evaluates the ability of the Maxcan system to search for different fibre types and colours under varying conditions. The system performed effectively in most situations, although it did have problems with some search combinations that a human operator would also find difficult in a manual search. The Maxcan system has the added advantages of being objective, consistent and able to do large batch searches unattended. These attributes make it very useful where a large number of tapes need to be searched in casework and also in research where large quantities of data need to be gathered within a reasonable time.

14.
J Forensic Sci ; 49(4): 707-15, 2004 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-15317184

RESUMO

The performance of two spray reagents, iodine-benzoflavone and ruthenium tetroxide (RTX), was evaluated and compared with the conventional technique currently used at the crime scene, that is, powdering. Neither the spray techniques nor powdering were shown to be suitable for all surfaces and ages of marks tested. On some surfaces such as glass and treated wood, powdering was still the superior technique, whereas the spray techniques produced better development on wallpaper, vinyl, and brick. Sequencing work showed that RTX was incompatible with powdering and cyanoacrylate (with a rhodamine 6G stain). Iodine-benzoflavone can be used successfully either before or after powdering in a sequence; however, it was incompatible with cyanoacrylate. Two non-CFC formulations of iodine-benzoflavone using HFC4310mee and HFE7100 solvents were tested and shown not to be as effective as the original Arklone (CFC-113) formulation; however, the HFC4310mee solvent is recommended as the most suitable replacement solvent. Due to the expense of the commercial RTX spray, attempts at formulating a more cost-effective version were also carried out. A formulation was developed that gave comparable development to the commercial version but at a much cheaper cost, and with a shelf life of up to two months. Recommendations are presented for which techniques are suitable for different surfaces and ages of marks. Powdering was shown to be the best technique on all ages of marks tested on treated wood, glass, and also on marks aged three days and older on paint. Iodine-benzoflavone was the best technique on wallpaper, vinyl, brick, and raw wood. RTX was the best detection technique for fresh marks and marks aged up to one day on wallpaper and paint.


Assuntos
Benzoflavonas , Dermatoglifia , Medicina Legal/métodos , Iodo , Compostos de Rutênio , Aerossóis , Humanos , Indicadores e Reagentes , Pós , Propriedades de Superfície
15.
Forensic Sci Int ; 226(1-3): 125-31, 2013 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-23375458

RESUMO

This study investigated the prevalence of glass particles on the headwear and head hair of two different population groups; the general public who do not work with glass, and glaziers from O'Brien(®) Glass Industries who work with glass and have regular contact with broken glass. The 232 samples collected from the head hair and headwear from the random population resulted in the recovery of 6 glass fragments in total on 6 individuals (i.e. one fragment each). All of these fragments were from head hair samples with no multiple fragments recovered. The two headwear samples that were taken revealed no fragments. These results were in contrast to the survey that was conducted on the head hair and headwear of 25 glaziers from O'Brien(®), in which 138 glass fragments were found in total on 24 of the 25 glaziers. The size and number of fragments found in each sample were also generally larger for the glaziers group. The results from this study indicate that the prevalence of glass on the head hair and head wear of the random population is very low in comparison to the head hair and headwear of those who have regular contact with breaking glass. The significance of this finding with respect to the interpretation of glass evidence is also discussed.

16.
Forensic Sci Int ; 230(1-3): 74-80, 2013 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-23611533

RESUMO

This paper describes the application of a luminescent lipid stain, nile red, for the development of latent fingermarks on porous surfaces. An optimised formulation is presented that provides rapid development of latent fingermarks on porous surfaces that are or have been wet. A comparison with physical developer (PD), the method of choice to enhance such fingermarks, indicated that nile red was a simpler and more stable technique for the development of fingermarks. The nile red formulation showed similar performance to PD across a range of substrates and ageing conditions, although PD still showed greater sensitivity on five-year-old examination booklets used in a pseudo-operational study. The pseudo-operational trial also indicated that nile red consistently developed different fingermarks to those enhanced by PD, suggesting that it preferentially targets a different fraction of the latent fingermark deposit. Significantly, the compatibility of nile red in a detection sequence with indanedione-zinc, ninhydrin and PD is reported.


Assuntos
Dermatoglifia , Corantes Fluorescentes , Oxazinas , Humanos , Indanos , Indicadores e Reagentes , Substâncias Luminescentes , Ninidrina , Papel , Porosidade , Propriedades de Superfície , Fatores de Tempo , Molhabilidade
17.
Forensic Sci Int ; 219(1-3): 208-14, 2012 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-22284074

RESUMO

Conventional fingermark powders rely on contrast induced by absorption/reflection (e.g. black powder) or luminescence in the visible region (e.g. Blitz Green(®)). In most cases, these powders provide sufficient contrast; however, in some circumstances surface characteristics can interfere with the visualisation of powdered fingermarks. Visualisation in the near infra-red (NIR) region, however, has been shown to eliminate interferences commonly encountered in the visible region. In this study, a mixture of rhodamine 6G and the NIR laser dye styryl 11 (STaR 11) was coated onto an aluminium oxide nanopowder and then mixed with silver magnetic powder to develop and visualise fingermarks in the NIR. When compared to Blitz Green(®), it was determined that the STaR 11 magnetic powder was better suited for marks deposited on textured surfaces and for older marks, whereas Blitz Green(®) performed better on smooth glossy surfaces. The ability of the STaR 11 mixed dye formulation to be visualised in both the visible and NIR regions also provides a significant advantage over conventional luminescent fingermark powders.


Assuntos
Compostos de Anilina , Dermatoglifia , Corantes Fluorescentes , Compostos de Quinolínio , Rodaminas , Óxido de Alumínio/química , Humanos , Luz , Luminescência , Nanopartículas , Pós , Prata , Propriedades de Superfície
18.
Forensic Sci Int ; 217(1-3): e23-6, 2012 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-22047749

RESUMO

This article describes the use of an anti-Stokes luminescent material (upconverter), yttrium vanadate doped with ytterbium and erbium (YVO(4):Er,Yb), for the development of latent fingermarks on a range of non-porous surfaces. Anti-Stokes luminescent materials emit light at shorter wavelengths than the excitation wavelength. This property is unusual in both natural and artificial materials commonly found as exhibits in forensic science casework. As a result, fingermark detection techniques based on anti-Stokes luminescence are potentially extremely sensitive and selective. Latent fingermarks on non-luminescent and inherently luminescent substrates, including Australian polymer banknotes (a well-known 'difficult' surface), were developed with YVO(4):Er,Yb by dry powder and wet powder techniques. The effectiveness of YVO(4):Er,Yb for fingermark detection was compared with that of cyanoacrylate fuming and of sodium yttrium tetrafluoride doped with ytterbium and erbium (NaYF(4):Er,Yb). The results illustrate some benefit of luminescent up-converting phosphors over traditional luminescence techniques for the detection of latent fingermarks.


Assuntos
Dermatoglifia , Medições Luminescentes/métodos , Cianoacrilatos , Érbio , Humanos , Porosidade , Pós , Propriedades de Superfície , Volatilização , Itérbio , Ítrio
19.
J Forensic Sci ; 56(6): 1505-13, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21790599

RESUMO

In current casework, most post-cyanoacrylate stains rely on luminescence emission in the visible region (400-700 nm). While traditional stains such as rhodamine 6G work well under most circumstances, some surfaces may generate background luminescence under the same conditions. Detection in the near-infrared region (NIR > 700 nm) has shown to be effective in minimizing the interferences from such surfaces. The laser dye styryl 11 generated strongly luminescent fingermarks when applied after cyanoacrylate fuming on all surfaces tested. When compared to rhodamine 6G, the dye was superior only when viewed in the NIR. Styryl 11 was subsequently combined with rhodamine 6G, and the mixed stain formulation (named StaR 11 by the authors) induced stronger luminescence compared with styryl 11 alone with an ability to visualize in both the visible and NIR regions. Reliable and consistent results were obtained when using either styryl 11 alone or the STaR 11 mixture. The enhancement achieved did not otherwise vary depending on the source of the fingermark secretions. With visualization possible in both the visible and NIR regions, the styryl 11/rhodamine 6G mixture showed significant potential as a post-cyanoacrylate stain.


Assuntos
Compostos de Anilina , Dermatoglifia , Corantes Fluorescentes , Luminescência , Compostos de Quinolínio , Rodaminas , Cianoacrilatos , Feminino , Humanos , Masculino , Porosidade , Propriedades de Superfície , Volatilização
20.
Forensic Sci Int ; 207(1-3): 145-9, 2011 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-20980110

RESUMO

This article describes the first use of an anti-Stokes material, or up-converter, for the development of latent fingermarks on a range of non-porous surfaces. Anti-Stokes materials can absorb long-wavelength light and emit light at a shorter wavelength. This property is unusual in both natural and artificial materials and so fingermark detection techniques based on anti-Stokes luminescence are potentially sensitive and selective. Latent fingermarks on luminescent and non-luminescent substrates, including Australian polymer banknotes (a well-known 'difficult' surface), were developed with sodium yttrium tetrafluoride doped with erbium and ytterbium (NaYF(4):Er,Yb) by dry powder, wet powder, and cyanoacrylate staining techniques. This study illustrates the potential of up-converter phosphors for the detection of latent fingermarks.


Assuntos
Dermatoglifia , Medições Luminescentes/métodos , Cianoacrilatos , Érbio , Fluoretos , Humanos , Microscopia Eletrônica de Varredura , Porosidade , Pós , Espectrometria por Raios X , Propriedades de Superfície , Volatilização , Itérbio , Ítrio
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