Sequencing of intersecting lines by combined lifting process and scanning electron microscopy

The chronological order in which two intersecting writing or typed strokes were made can be determined for several combinations of writing media by scanning electron microscope (SEM) examination, a lifting and transfer technique using Kromekote paper, or a combination of the transfer technique followed by SEM examination of the remaining material in the intersection. When non-destructive examination cannot provide unambiguous determination of sequence, judicious choice by the document examiner of which technique to use for a given combination of writing media and paper type can be made using known characteristics of the materials involved. The range of line-crossings which can be reliably sequenced is greater using a combined transfer and SEM technique than when the examination is limited to either technique alone.     

A preliminary investigation into the use of alginates for the lifting and enhancement of fingermarks in blood

Recent studies have reported the use of alginate in the lifting and subsequent enhancement of footwear marks in blood. A study was set up to assess the use of such a method in the treatment of fingermarks in blood on a variety of porous, non-porous and semi-porous surfaces. Other variables included ageing of the fingermarks in blood and the application of chemicals prior to or post-alginate lifting. All different variations were compared to direct chemical treatment of the substrate. The results demonstrated that alginate is not compatible with certain substrates (e.g. glass and tile). On substrates that were compatible with alginate (e.g. fabric and paper), the enhanced fingermarks on the alginate cast and the enhanced fingermarks on the post-alginate substrates appeared, overall, inferior compared to direct chemical enhancement without the use of alginate. A further variation using water-based protein stains directly mixed with the alginate appeared to provide enhancement directly on the substrate as well as simultaneous lifting and enhancing the fingermarks in blood on the alginate cast.     

Ultra-trace analysis of illicit drugs from transfer of an electrostatic lift

This article introduces a method of collecting and analysing drug residues that integrates both electrostatic lifting and nanomanipulation-coupled to nanospray ionization mass spectrometry. The application of this hyphenated technique exhibits a useful means of collection and extraction of drug residues with ease and efficiency along with decreased limits of detection. From this method, it will be shown how increased sensitivity of analysis and lower limits of detection for drug analysis can be achieved. The same principles that allow lifting of dust prints by electrostatic lifting can be applied to lifting drug residues. Probing of the drug residues by nanomanipulation occurs directly from the lift, which provides a great platform for extraction. Nanomanipulation-coupled to nanospray ionization-mass spectrometry has been used for the extraction of trace analytes in previous experiments and is known as a very sensitive technique for the detection of ultra-trace residue. This method will demonstrate the electrostatic lifting of drug residue particles from a surface followed by extraction and ionization with nanomanipulation-nanospray ionization. The utility of this novel methodology allows for a more productive analysis when presented with ultra-trace amounts of sample.     

The spectroscopic detection of exogenous material in fingerprints after development with powders and recovery with adhesive lifters

The application of powders to fingerprints has long been established as an effective and reliable method for developing latent fingerprints. The powders adhere to the ridge pattern of the fingerprint only, thus allowing the image to be visualised. Fingerprints developed in situ at a crime scene routinely undergo lifting with specialist tapes to facilitate subsequent laboratory analysis. As with all recovered evidence these samples would be stored in evidence bags to allow secure transit from the scene to the laboratory and also to preserve the chain of evidence. In this paper, the application of Raman spectroscopy for the analysis of exogenous material in latent fingerprints is reported for contaminated fingerprints that had been treated with powders and also subsequently lifted with adhesive tapes. A selection of over the counter (OTC) analgesics were used as samples for the analysis and contaminated fingerprints were deposited on clean glass slides. The application of aluminium or iron based powders to contaminated fingerprints did not interfere with the Raman spectra obtained for the contaminants. In most cases background fluorescence attributed to the sebaceous content of the latent fingerprint was reduced by the application of the powder thus reducing spectral interference. Contaminated fingerprints developed with powders and then lifted with lifting tapes were also examined. The combination of these two techniques did not interfere with the successful analysis of exogenous contaminants by Raman spectroscopy. The lifting process was repeated using hinge lifters. As the hinge lifters exhibited strong Raman bands the spectroscopic analysis was more complex and an increase in the number of exposures to the detector allowed for improved clarification. Raman spectra of developed and lifted fingerprints recorded through evidence bags were obtained and it was found that the detection process was not compromised in any way. Although the application of powders did not interfere with the detection process the time taken to locate the contaminant was increased due to the physical presence of more material within the fingerprint. The presence of interfering Raman bands from lifting tapes is another potential complication. This, however, could be removed by spectral subtraction or by the choice of lifting tapes that have only weak Raman bands.     

藻酸盐材料在提取深色织物上潜血足迹的应用

目的建立一种用藻酸盐齿科材料转印显现纺织物上血足迹的方法。方法依据藻酸盐能和纺织物上血足迹中的血结合,从而使足迹被转印到藻酸盐模上,并通过染色增强反差。结果藻酸盐印模材料转印法能够在不破坏织物客体的情况下清楚的反映出血足迹细节特征。结论藻酸盐类齿科材料能够转印、提取显现织物上血足迹,尤其是潜在血足迹,并反映出其细节特征。     

A comparative research of two lifting methods: electrostatic lifter and gelatin lifter

Two-dimensional dust shoeprints are often of very high resolution and contain unique features. Lifting these prints in the most effective method may contribute much to preserving these fine details. A research was conducted by experts from Israel and Switzerland to compare gelatin lifters and electrostatic lifters for lifting shoeprints. Several substrates were chosen, and on each material a set of dry dust shoeprints was made. A set of wet prints was made on paper as well. The shoeprints were approximately of the same quality, and the only variable was the nature of the material. On substrates indifferent to the method used, the preferable sequence was tested. Gelatin lifter was superior on most substrates and for wet prints. The superior sequence for using both methods is electrostatic lifting followed by gelatin lifter.     

Lifting Bloody Footwear Impressions Using Alginate Casts Followed by Chemical Enhancement

A method for lifting bloody footwear impressions using alginate casts and enhancing the lifted impressions with amido black is presented. On rough or dark substrates, background interferences may conceal significant details of footwear impressions. Illumination with alternative light sources and chemically enhancing the bloody footwear impressions may reveal additional details, but sometimes, lifting footwear impressions prior to enhancing is the only way to expose hidden details (by using blood reagents not adequate on the original). Several cast formulations were tested for lifting the footwear impressions. The best results were achieved using Aroma fine^®. Enhancement of the footwear impressions was attempted with several reagents prior to lifting, during the casting process, and on the lifted footwear impressions. Applying amido black to footwear impressions lifted with alginate produced the sharpest and most detailed footwear impressions. Alginate castings followed by chemical enhancement with amido black may produce high‐quality footwear impressions for comparison.     

Recovery of Trace DNA on Clothing: A Comparison of Mini‐tape Lifting and Three Other Forensic Evidence Collection Techniques

Trace DNA is often found in forensic science investigations. Experience has shown that it is difficult to retrieve a DNA profile when trace DNA is collected from clothing. The aim of this study was to compare four different DNA collection techniques on six different types of clothing in order to determine the best trace DNA recovery method. The classical stain recovery technique using a wet cotton swab was tested against dry swabbing, scraping and a new method, referred to as the mini‐tape lifting technique. Physical contact was simulated with three different “perpetrators” on 18 machine‐washed garments. DNA was collected with the four different DNA recovery methods and subjected to standard PCR‐based DNA profiling. The comparison of STR results showed best results for the mini‐tape lifting and scraping methods independent of the type of clothing. The new mini‐tape lifting technique proved to be an easy and reliable DNA collection method for textiles.     

Salafi and Islamist Londoners: Stigmatised minority faith communities countering al-Qaida

The paper highlights the paradoxical position of certain Salafi and Islamist communities in London who have consistently demonstrated skill, courage and commitment in countering al-Qaida propaganda and recruitment activity while simultaneously facing ill-founded criticism from other Muslim communities and secular political lobbyists for creating the conditions that gave rise to the al-Qaida phenomena. In doing so the paper compares the experience of Salafi and Islamist communities living in London during an ongoing terrorist campaign by al-Qaida with Jewish and Irish Catholic communities living in London during earlier terrorist campaigns against the UK’s capital city. In each instance community policing is shown to have a crucial role to play in terms of reassurance for minority faith communities and the prevention of terrorism. However, the intersection between policing and counter-terrorism is shown to produce tensions that may weaken minority community confidence in policing and thereby reduce proactive community support for counter-terrorism measures. At this intersection a London policing initiative is shown to have developed proactive counter-terrorism partnerships with Salafi and Islamist community groups of a pioneering nature. In consequence the same critics who conflate Salafis and Islamists with an urgent terrorist threat to London have accused this policing initiative of appeasing extremism.     

The Optimal Distance of the Electrode to the Lifting Film Surface when Lifting Dust Footwear Impressions Using an Electrostatic Dust Print Lifter

Footwear impressions are one of the valuable physical evidence encountered at crime scenes and its identification can facilitate narrowing down the suspects and establishing the identity of the criminals. The technique of electrostatic lifting (ESL) dust shoeprints at crime scenes is well established with scenes of crime examiners. And in the procedure, the recovery of the original item containing the impression should be made as good as it can and not damage the marks. In this study, the different particle sizes of SiO₂ were used to simulate dust and light soil residues, comparing different particle sizes and electrode positions were used to compare the adsorption ability on the surface of electrostatic lifting film in high‐voltage electrostatic field for the collection of shoeprints. The results indicated that lifting film in electrostatic field will be pressed down to the dust surface, the compaction and electrostatic adsorption force will vary with the distance between the high‐voltage electrode and film surface. Reducing the distance can increase the electric field strength near the lifting film, and the adsorption capacity of Mylar aluminum‐plating film to dusts can be improved significantly. Adsorption capacity of the lifting film was related to the size of dust particles and significantly improved with the increase of the particle charge. The optimum distance which can get the best adsorption capacity between the electrode and film surface is from 10 to 15 mm.     

Knowledge and Insanity

This paper lies at the intersection of law and logic. Logical analysis is employed to attempt to make headway in what has proven to be an intractable interpretive debate over a defence provision of the Indian Penal Code.     

成趟足迹提取方法导致误差的探讨

目的研究提取成趟足迹的低误差方法。方法比较相同条件下一次性拍照、分段连续拍照和扫描仪提取所产生的误差的大小。结果扫描仪提取法的误差最小。结论扫描仪提取足迹的方法易于掌握,适合基层技术员推广使用。     

Detection of nitro-organic and peroxide explosives in latent fingermarks by DART- and SALDI-TOF-mass spectrometry

The ability of two mass spectrometric methods, surface-assisted laser desorption/ionization-time of flight-mass spectrometry (SALDI-TOF-MS) and direct analysis in real time (DART-MS), to detect the presence of seven common explosives (six nitro-organic- and one peroxide-type) in spiked latent fingermarks has been examined. It was found that each explosive could be detected with nanogram sensitivity for marks resulting from direct finger contact with a glass probe by DART-MS or onto stainless steel target plates using SALDI-TOF-MS for marks pre-dusted with one type of commercial black magnetic powder. These explosives also could be detected in latent marks lifted from six common surfaces (paper, plastic bag, metal drinks can, wood laminate, adhesive tape and white ceramic tile) whereas no explosive could be detected in equivalent pre-dusted marks on the surface of a commercial lifting tape by the DART-MS method due to high background interference from the tape material. The presence of TNT and Tetryl could be detected in pre-dusted latent fingermarks on a commercial lifting tape for up to 29 days sealed and stored under ambient conditions.     

Selection of an adhesive tape suitable for forensic fiber sampling

Five commercial adhesive tapes were tested for fiber uptake and saturation, for recovery and for ease of analysis. On the basis of the results, a high tack adhesive tape has been selected to be used for forensic fiber sampling. This adhesive tape is used as sampling material in two different micro trace kits. The first tape lifting kit is used mainly for the sampling of cars and the second is a 1:1 tape lifting kit for the collection of fibers on a corpse.     

Gold-plating of Mylar lift films to capitalize on surface enhanced Raman spectroscopy for chemical extraction of drug residues

The method of residue extraction through electrostatic lifting provides a distinctive mode of performing ultra-trace analysis. These lifts provide a medium for analyte extraction via nanomanipulation-coupled to nanospray ionization-mass spectrometry (NSI-MS). This method of extraction can be coupled to Raman spectroscopy for supplemental verification of analytes using surface enhanced Raman scattering (SERS). The gold surface used for SERS provides an enhanced effect on peak signal intensity allowing ultra-trace amounts to be detected more effectively. The aim of this research is to utilize gold-coated films with electrostatic lifting in order to collect latent materials and analyze chemicals of interest contained in them via SERS.     

Species justice for police eagles: analyzing the Dutch ‘flying squad’ and animal-human relations

Dutch national police recently became the world’s first force to train eagles to combat the growing rise of drones within the Netherlands. Partnering with an eagle-training security firm, Guard From Above, both organizations believe using eagles to intercept and retrieve drones is the most effective countermeasure to handle rogue drones in the skies. This paper questions whether such a police operation to increase air security respects the rights of the eagles and ensures the animals’ protection from unreasonable injury, harm and suffering. Such an examination lies at the intersection of green criminological perspectives and critical security studies’ scholarship, an intersection of which I consider more thoroughly. By implementing a qualitative media analysis, this paper examines twenty media reports detailing the facts of the Dutch ‘Flying Squad.’ I contend that police agencies in the West must seriously consider such eagle initiatives as intrusive, harmful practices. The findings suggest that conceptualizing the eagles as exceptional ‘biotechnological’ state agents may increase sky security in Western countries, but such anthropocentric logics of security minimize the concerns for ‘species justice’ and the safeguards for eagles.     

A method for impregnating nylon transfer membranes with leucocrystal violet for enhancing and lifting bloody impressions

The objective of this research project was to demonstrate a quick and easy method for impregnating nylon transfer membranes with leucocrystal violet (LCV) for the purpose of lifting and enhancing impressions made in blood. A stamp that would simulate fine detail found in fingerprints or footwear was used to create impressions on a variety of substrates. Four different LCV formulations were tested to determine the effectiveness of the prepared membranes in lifting and enhancing the impressions. Further investigation involved the feasibility of using the LCV membranes in the field by studying the shelf life and storage of the impregnated membranes and the longevity of the lifted impressions. One of the formations studied demonstrated superior lifting and enhancing capabilities, as well as a prolonged shelf life and a resilience of the lifted impressions, thus proving LCV to be an extremely valuable technique.     

The determination of sequence of crossing strokes by the “Kromekote” paper lifting process and by the scanning electron microscopic method

The authors present the results obtained while applying the “Kromekote paper” lifting process first proposed by Igoe and Reynolds in 1979 [1] and later in a modified form in 1980 and 1982 by Godown [2]. They also present the results of their research to determine the writing order of crossing strokes using the Scanning Electron Microscopic technique, research that was restarted after the publication of an article by Waeschle [3].     

Examining the effects of paper type, pen type, writing pressure and angle of intersection on white and dark dominance in ESDA impressions of sequenced strokes--an application of the likelihood ratio

Questioned document casework can occasionally involve the sequencing of impressions. Although some conclusions can be drawn from looking at ESDA traces of intersections there is currently no way of assessing the strength of the observations made in any given case. Using a range of paper and pen types this work examines points of intersection and evaluates the results statistically in order judge the value of the results obtained.     

Chemical enhancement of footwear impressions in blood deposited on fabric — Evaluating the use of alginate casting materials followed by chemical enhancement

Most footwear marks made in blood on a surface such as fabric tend to be enhanced in situ rather than physically recovered using a lifting technique prior to enhancement. This work reports on the use of an alginate material to recover the impressed footwear marks made in blood and deposited on a range of fabric types and colours. The lifted marks were then enhanced using acid black 1 and leuco crystal violet with excellent results.This presents a new method for the lifting and recovery of blood impressions in situ from crime scene followed by subsequent mark enhancement of the lifted impression.