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In 2017 Cooktown resident Donna Steele was murdered and the case remained unsolved for more than a year. The forensic evidence from the investigation included two lengths of synthetic twine and a new protocol for the comparison of twine was developed to enhance the potential value of any evidence. The method was developed using 23 samples of similar twine collected across Australia. Traditional methods of physical and microscopic comparisons and polymer analysis by infrared spectroscopy were retained. Micro-spectrophotometry was used as an objective assessment of colour and was able to identify five groupings within the background samples. Measurements of hydrogen and carbon stable isotopic composition provided further delineation of the background samples. Combining traditional methods with micro-spectrophotometry and stable isotope measurements, the two case samples were found to be distinct from the background population and were indistinguishable when compared to each other.

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Repetitive mild traumatic brain injury (rmTBI) results in a myriad of symptoms, including vestibular impairment. The mechanisms underlying vestibular dysfunction in rmTBI patients remain poorly understood. Concomitantly, acute hypogonadism occurs following TBI and can persist chronically in many patients. Using a repetitive mild closed-head animal model of TBI, the role of testosterone on vestibular function was tested. Male Long Evans Hooded rats were randomly divided into sham or rmTBI groups. Significant vestibular deficits were observed both acutely and chronically in the rmTBI groups. Systemic testosterone was administered after the development of chronic vestibular dysfunction. rmTBI animals given testosterone showed improved vestibular function that was sustained for 175 days post-rmTBI. Significant vestibular neuronal cell loss was, however, observed in the rmTBI animals compared to Sham animals at 175 days post-rmTBI and testosterone treatment significantly improved vestibular neuronal survival. Taken together, these data demonstrate a critical restorative role of testosterone in vestibular function following rmTBI. This study has important clinical implications because it identifies testosterone treatment as a viable therapeutic strategy for the long-term recovery of vestibular function following TBI.

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RATIONALE: Analysis of water-based personal lubricants can provide pivotal information to law enforcement regarding sexual assault allegations, particularly in the absence of biological evidence. Traditional methodology for the extraction and analysis of water-based lubricants is cumbersome, time-consuming, and is often not sufficiently selective or sensitive to fully characterise the wide range of chemical components present within complex formulations. METHODS: Liquid extraction surface analysis (LESA) was deployed in combination with high-resolution mass spectrometry (HRMS) and tandem mass spectrometry (MS/MS) to screen a range of water-based lubricants directly from contaminated cotton fabric. Rehydration of the fabric was the only sample preparation required. RESULTS: Analysis of ten different water-based lubricants by nano-electrospray ionisation mass spectrometry in negative ion mode enabled discrimination based on the presence or absence of nine compounds, which were identified by comparison of their MS/MS spectra with those of available standards. Lubricants were successfully detected by LESA from stained fabric surfaces; even following extended periods of time between deposition and sampling. CONCLUSIONS: A library encompassing the common components of water-based lubricants has been established using HRMS and tandem mass spectrometry to enable identification of personal lubricant formulations and differentiation between suppliers.

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Plastic cable ties can be utilised in a range of serious criminal activities and a comparison of cable ties, or fragments, may form part of the physical evidence presented to a Court of law. This research assessed the potential value of evidence based on the analysis of plastic cable ties. Twenty packets of black coloured plastic cable ties (nominally 200mm×4.8mm) were purchased in pack sizes ranging from 25 to 100 individual cable ties (Brisbane, Australia, March 2015). Representative samples from each packet were visually examined, compared and tested to determine their physical dimensions, chemical compositions and stable isotopic compositions (δ2H, δ13C and δ15N). All of the individual cable ties from a given packet were found to be indistinguishable with respect to appearance, physical, chemical and isotopic measurements (within-batch variability). Individual cable ties were also found to be isotopically homogeneous with respect to hydrogen, carbon and nitrogen. All of the cable ties analysed were found to have very similar chemical compositions and to be manufactured predominantly from nylon 6,6. The elemental compositions of composite samples, prepared from each packet, were found to be highly variable and, as such, were of very limited value. Cable ties from ten of the twenty packets were uniquely characterised by physical appearance (between-batch variability). Physical measurements such as the width, thickness and tooth-count of the grip section did not provide additional discrimination. Cable ties from nineteen of the twenty packets were uniquely characterised by isotopic composition, based on δ2H and δ15N measurements. Samples from two packets of Crescent brand cable ties were found to be indistinguishable with respect to all of the tests applied in this study. These two packets were inadvertently purchased from the same retailer and had the same barcode and batch number. It was considered a reasonable assumption that these two packets originated from the same manufacturing batch. The authors reason that a likelihood ratio (that might be presented to a Court of law) can be derived from this type of discrete data based on a calculation of the possible combinations of distinguishable objects (unordered sampling with replacement) in a convenience sample collected from the background population. In this example, a database of 19 distinguishable objects can yield a likelihood ratio as high as 210, with a verbal equivalent of "moderately strong support" for a proposition that two cable ties have the same isotopic composition because they originate from the same batch rather than by random chance.

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OBJECTIVE: To validate standard self-report questionnaires for depression screening in patients with rheumatoid arthritis (RA) and compare these measures to one another and to the Montgomery-Åsberg Depression Rating Scale (MADRS), a standardized structured interview. METHODS: In 9 clinical centers across Germany, depressive symptomatology was assessed in 262 adult RA patients at baseline (T0) and at 12 ± 2 weeks followup (T1) using the World Health Organization 5-Item Well-Being Index (WHO-5), the Patient Health Questionnaire (PHQ-9), and the Beck Depression Inventory II (BDI-II). The construct validity of these depression questionnaires (using convergent and discriminant validity) was evaluated using Spearman's correlations at both time points. The test-retest reliability of the questionnaires was evaluated in RA patients who had not undergone a psychotherapeutic intervention or received antidepressants between T0 and T1. The sensitivity and the specificity of the questionnaires were calculated using the results of the MADRS, a structured interview, as the gold standard. RESULTS: According to Spearman's correlation coefficients, all questionnaires met convergent validity criteria (ρ > |0.50|), with the BDI-II performing best, while correlations with age and disease activity for all questionnaires met the criteria for discriminant validity (ρ < |0.50|). The only questionnaire to meet the predefined retest reliability criterion (ρ ≥ 0.70) was the BDI-II (rs = 0.77), which also achieved the best results for both sensitivity and specificity (>80%) when using the MADRS as the gold standard. CONCLUSION: The BDI-II best met the predefined criteria, and the PHQ-9 met most of the validity criteria, with lower sensitivity and specificity.

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Scald burns are the most common thermal injury among children. A small subset of pediatric scald burns are complicated by the need for mechanical ventilation (MV). Studies suggest that 4 to 5% of pediatric scald burns will require MV, and these patients tend to be younger with larger burns. Identifying why pediatric patients with scald burns require MV has remained unclear, and few studies have sought to elucidate possible mechanisms. After institutional review board approval, a retrospective review of all pediatric patients with scald burns admitted to the Burn Center between 2010 and 2013 was conducted. Variables collected included age, sex, weight, height, race, ethnicity, socioeconomic status or type of insurance, hospital length of stay, burn size and location, Department of Child and Family Services (DCFS) involvement, time to intubation from admission, reason for intubation, need for MV, duration of MV, need for operative intervention, 24-hour and 48-hour total fluid intake and urine output, glucose levels, infectious complications, comorbidities, and mortality. Patients who required MV were then compared with those who did not require MV to identify statistically significant differences between groups. The MV patients (n = 6) and nonventilated patients (n = 339) did not show significant differences in regards to gender, body mass index, ethnicity, and type of insurance; however, MV patients were younger and had larger burns. The mean age of MV patients was 8.2 + 5.0 months compared with 40.7 + 45.2 months for non-MV (P = .002). The mean percentage of TBSA burn in MV patients was 17.3 + 9.0% compared with 4.5 + 3.9% for non-MV (P < .001). Burn location was significant, and 66.6% of MV patients had burns on the face or neck compared with 23.6% of non-MV (P = .015). MV patients were more likely to have been victims of child abuse, as DCFS was involved in 67% of MV patients vs. 28% of non-MV patients (P = .036). Fifty percent of patients requiring MV had either a preceding upper respiratory infection, diagnosis of asthma, or congenital defects, compared with 6% of non-MV patients (P = .004). MV patients received more fluids for 48 hours compared with non-MV patients (2275.7 vs. 1332.3 ml, P = .013) and had a higher 48-hour urine output (2.34 vs. 1.34 ml/kg/hr, P = .013). Pediatric scald burns that require MV have an increased mortality risk and length of stay. MV patients were younger with larger burns. They received more fluids than non-MV patients, and child abuse, asthma, and stress hyperglycemia within the first 72 hours of injury were common among MV patients. Importantly, burn size and previous history of asthma were found to be independent predictors of the need for MV.

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