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Surveillance is ubiquitous in modern society, allowing continuous monitoring of areas that results in capturing criminal (or suspicious) activity as footage. This type of trace is usually examined, assessed and evaluated by a forensic examiner to ultimately help the court make inferences about who was on the footage. The purpose of this study was to develop an analytical model that ensures applicability of morphometric (both anthropometric and morphological) techniques for photo-comparative analyses of body and gait of individuals in CCTV images, and then to assign a likelihood ratio. This is the first paper of a series: This paper will contain feature extraction to observe repeatability procedures from a single observer, in turn, producing the frequency and distinctiveness of the feature set within the given population. To achieve this, an Australian population database of 383 subjects (stance) and 268 subjects (gait) from both sexes, all ages above 18 and ancestries was generated. Features were extracted, defined, and their rarity viewed among the developed database. Repeatability studies were completed in which stance and gait (static and dynamic) features contained low levels of repeatability error (0.2%–1.5 TEM%). For morphological examination, finger flexion and feet placement were observed to have high observer performance. [ABSTRACT FROM AUTHOR]

Tattoos are secondary identifiers that can be used to provide a presumptive identity and provide information about a deceased individual to a case. Additional information may be available through the analysis of the visual presentation of tattoos. The aim of this study was to examine the morphological changes of tattoos during the decomposition of a human donor in an Australian environment. Using time-lapse cameras recording for 16 months, stills were extracted and tattoos were quantified using ImageJ. A full analysis was completed on three tattoos, while a fourth tattoo was partially analysed. The tattoos showed the most change in area during the bloat stage of decomposition, staying relatively constant in size for the remainder of the study. The detailed shape of the outlines showed the morphological effect of desiccation as part of decomposition and continued to change until the tattoo was no longer visible. Of the tattoos fully analysed, two became redundant as secondary identifiers on day 294, the other on day 333, all due to lack of visibility. This information is useful during investigations of unknown deceased persons; in this case, the stage of decomposition influenced the presentation of the tattoo. [ABSTRACT FROM AUTHOR]

Post-mortem movement relating to the disarticulation or positional change of entire limbs is relevant to a forensic investigator when examining a deceased person. Understanding that the position a body is found is not necessarily the way it was left changes the approach an examiner must take when investigating any death. This study quantified post-mortem movement of a human donor decomposing in an Australian environment over 16 months: 1) progressive measurement of the angles of joints; and 2) distance of separation between the articulating points of bones. ImageJ software was used to calculate angles and the distances between structures from time-lapse images. Movement was detected at all joints of the upper and lower limbs, occurring at all stages of decomposition across the study. Significant movement of the joints occurred as a result of bloat during the early stages of decomposition, and again during the advanced stages of decomposition as the soft tissue desiccated. Disarticulation was observed in the late stages of decomposition in all limbs and was not exclusive to short or long bones. Disarticulation also generated significant movement between skeletal structures in late decomposition. The results demonstrate that it is essential to consider post-mortem movement when investigating unexplained deaths. [ABSTRACT FROM AUTHOR]

Three-dimensional impressions are typically photographed and cast for further comparison when reference items become available to investigators. Three-dimensional scanning has been proposed as a more time-efficient and objective, less destructive method for footwear impression analysis. This project sought to acquire repeat scans of outsole footwear impressions and corresponding shoes at high resolutions to investigate the precision and accuracy of 3D scanning on footwear and impressions. Impressions were created using three footwear types representative of footwear encountered in casework. Scans of impressions were created using the Artec Spider structured-light scanner. Calculations of the statistical variability between scans were carried out using the CloudCompare software package. The distance between corresponding points within the impression tested for precision (n = 6) averaged 0.45 mm, σ 0.29 mm. When comparing the impression to the reference shoe, the distance between corresponding points averaged 2.41 mm, σ 1.98 mm. The maximal differences within the scans were at the toe of the shoe and may be due to flexion, as well as damage to the soil around the edges of the impression. This research has validated the hardware and software used to acquire data from a 3D impression and from the reference item that produced the trace. [ABSTRACT FROM AUTHOR]

Chemical reagents for serial number restoration are designed to exploit the plastic deformation zone below the obliterated serial number. Most techniques in operational use are variants of Fry's Reagent. This technique uses toxic, corrosive chemicals and requires a skilful operator in the laboratory. Fry's Reagent can also be destructive of the firearm due to rusting. In an attempt to find a non-toxic, non-destructive alternative to Fry's Reagent, this project tested the use of liquid dye penetrants (LDPs), a non-destructive examination technique to detect cracks and imperfections used in the welding industry, for the restoration of obliterated serial numbers. Steel plates bearing an obliterated serial number with a range of obliteration depths were subjected to LDP treatment under various treatment conditions. The results using LDPs were negative for all obliteration depths and all test conditions attempted. Some of the serial numbers were subsequently restored successfully with Fry's reagent, proving that the plastic deformation zone was present on the steel plates below the obliteration. Further work to develop a non-toxic, non-destructive serial number restoration process will be undertaken. [ABSTRACT FROM AUTHOR]

A total of 1,215 pigs (L337×1050, PIC, Hendersonville, TN) were used in a 156-d wean-to-finish experiment. Pigs were weaned at 21 d of age and placed in pens based on initial body weight (BW) with 27 pigs/pen. There were three dietary treatments including a: 1) control; 2) pigs fed diets containing AviPlus (microencapsulated sorbic and citric acids and synthetic thymol and vanillin botanicals; Vetagro Inc., Chicago, IL) during the nursery and finisher phases; or 3) pigs fed AviPlus during the nursery but not the finishing phase. AviPlus was included at 2.72 kg/ton from d 0 to 21, 0.90 kg/ton from d 21 to 42, and 0.45 kg/ton from d 42 to 156. Thus, there were 15 control pens and 30 Aviplus pens in the nursery and 15 pens for the 3 treatments in the finisher phase. On d 42, pigs were transported as intact pens to the finishing facility. Data were analyzed as a RCBD with pen as experimental unit. For the overall nursery period (d 0 to 42), pigs fed AviPlus had improved (P < 0.05) G:F, with no evidence of difference (P > 0.05) for d 42 BW, ADG, or ADFI. For the overall finishing period (d 42 to 156) and overall experimental period (d 0 to 156), there was no evidence of difference (P > 0.05) for BW, ADG, ADFI, or G:F. There was no evidence of difference (P > 0.05) observed for mortality and removals during the nursery, finisher, or overall. In summary, providing AviPlus during the nursery improved nursery G:F, but there was no effect on overall wean-to-finish performance. [ABSTRACT FROM AUTHOR]