A snapshot of injecting drug consumption from the analysis of used syringes within the Medically Supervised Injecting Centre in Sydney, Australia.

INTRODUCTION: The administration of illicit drugs by injection is associated with considerable harm, including an increased risk of overdose. The chemical analysis of used syringes can enhance knowledge on injecting drug consumption beyond traditional data sources (self-report surveys). This additional information may be useful during significant global events like the COVID-19 pandemic. This study aimed to examine a snapshot of the drugs injected at the Medically Supervised Injecting Centre (MSIC) in Sydney, Australia, in 2019-2020. METHODS: Used syringes were collected from MSIC across three periods throughout 2019 and 2020 (February 2019, March-April 2020 and June-September 2020). Drug residues were extracted from used syringes using methanol before detection by gas chromatography-mass spectrometry and ultra-performance liquid chromatography-tandem mass spectrometry. The chemical analysis results were compared to self-report data obtained from MSIC clients. RESULTS: Heroin (46-53%), methamphetamine (24-34%) and pharmaceutical opioids (15-27%) were the most common drug residues detected. The chemically detected drugs had declining coherence with the drugs self-reported by MSIC clients across the time periods examined. DISCUSSION AND CONCLUSIONS: There was no significant change in the drugs injected (heroin, methamphetamine and pharmaceutical opioids) across the three periods collected throughout varying COVID-19 lockdown restrictions. Changes in the frequency of other drugs injected and discrepancies between chemical analysis and self-report were potentially related to regulatory changes, degradation or misinformed sales. Routine chemical analysis of used syringes has provided an alternative information source to promote awareness of current drug trends and aid harm reduction.

Improvement in severe asthma patients receiving biologics and factors associated with persistent insufficient control: a real-life national study.

BACKGROUND: Biological therapies have revolutionized the treatment of severe asthma with type 2 inflammation. Although such treatments are very effective in reducing exacerbation and the dose of oral steroids, little is known about the persistence of symptoms in severe asthma patients treated with biologics. PURPOSE: We aim to describe asthma control and healthcare consumption of severe asthma patients treated with biologics. DESIGN: The Second Souffle study is a real-life prospective observational study endorsed by the Clinical Research Initiative in Severe Asthma: a Lever for Innovation & Science Network. METHODS: Adults with a confirmed diagnosis of severe asthma for at least 12 months' duration were enrolled in the study. A self-administered questionnaire including the Asthma Control Questionnaire (ACQ), Asthma Quality of Life Questionnaire (AQLQ) and a compliance evaluation test was given to the patients. Healthcare consumption within 12 months prior to enrolment was documented. In patients receiving biologics, doctors indicated whether the patients were biologic responders or non-responders. RESULTS: The characteristics of 431 patients with severe asthma were analysed. Among them, 409 patients (94.9%) presented asthma with type 2 inflammation (T2 high) profile, and 297 (72.6%) patients with a T2 high phenotype were treated with a biologic. Physicians estimated that 88.2% of patients receiving biologics were responders. However, asthma control was only achieved in 25.3% of those patients (ACQ > 0.75). A high proportion of patients (77.8%) identified as responders to biologics were not controlled according to the ACQ score. About 50% of patients continue to use oral corticosteroids either daily (25.2%) or more than three times a year for at least three consecutive days (25.6%). Gastro-oesophageal Reflux Disease (GERD) and Obstructive Sleep Apnoea syndrome (OSA) were identified as independent factors associated with uncontrolled asthma. CONCLUSION: Although a high proportion of severe asthma patients respond to biologics, only 25.3% have controlled asthma. GERD and OSA are independent factors of uncontrolled asthma.

Theratyping cystic fibrosis patients to guide elexacaftor/tezacaftor/ivacaftor out-of-label prescription.

BACKGROUND: Around 20% of people with cystic fibrosis (pwCF) do not have access to the triple combination elexacaftor/tezacaftor/ivacaftor (ETI) in Europe because they do not carry the F508del allele on the CF transmembrane conductance regulator (CFTR) gene. Considering that pwCF carrying rare variants may benefit from ETI, including variants already validated by the US Food and Drug Administration (FDA), a compassionate use programme was launched in France. PwCF were invited to undergo a nasal brushing to investigate whether the pharmacological rescue of CFTR activity by ETI in human nasal epithelial cell (HNEC) cultures was predictive of the clinical response. METHODS: CFTR activity correction was studied by short-circuit current in HNEC cultures at basal state (dimethyl sulfoxide (DMSO)) and after ETI incubation and expressed as percentage of normal (wild-type (WT)) CFTR activity after sequential addition of forskolin and Inh-172 (ΔI ETI/DMSO%WT). RESULTS: 11 pwCF carried variants eligible for ETI according to the FDA label and 28 carried variants not listed by the FDA. ETI significantly increased CFTR activity of FDA-approved CFTR variants (I601F, G85E, S492F, M1101K, R347P, R74W;V201M;D1270N and H1085R). We point out ETI correction of non-FDA-approved variants, including N1303K, R334W, R1066C, Q552P and terminal splicing variants (4374+1G>A and 4096-3C>G). ΔI ETI/DMSO%WT was significantly correlated to change in percentage predicted forced expiratory volume in 1 s and sweat chloride concentration (p<0.0001 for both). G85E, R74W;V201M;D1270N, Q552P and M1101K were rescued more efficiently by other CFTR modulator combinations than ETI. CONCLUSIONS: Primary nasal epithelial cells hold promise for expanding the prescription of CFTR modulators in pwCF carrying rare mutants. Additional variants should be discussed for ETI indication.

Production of artificial fingermarks. Part II - The use of a modified inkjet printer for the deposition of synthetic secretions.

This study is the second part of a larger body of research dedicated to the production of synthetic secretions and the use of an inkjet printer to deposit realistic artificial fingermarks. An artificial emulsion combining eccrine and sebaceous compounds, which was described and tested in the first part of this research, was used as it showed a promising compatibility with common detection techniques. An inkjet printer was modified to print the emulsion on two different substrates: paper (porous) and acetate (non-porous). After optimisation of the printing parameters, multiple fingermarks were printed and processed with a range of standalone detection techniques: 1,2-indanedione-zinc, ninhydrin, Oil Red O, and physical developer on paper, and cyanoacrylate fuming, rhodamine 6G, gold/zinc vacuum metal deposition, and silver black powder on acetate. The detection techniques were also applied in sequence, which is considered one of the biggest advantages of the emulsion over simpler amino acid mixtures that are usable with amino acid reagents only. Natural fingermarks deposited by a single donor were processed with the same techniques for comparison. The effect of water immersion was also investigated, where fingermarks printed on paper were immersed in water for 15 min, before being processed with 1,2-indanedione-zinc and Oil Red O. The results showed that realistic-looking fingermarks could be printed on paper and that printing on acetate was also possible albeit of lower quality due to the nature of the substrate. The artificial fingermarks were successfully enhanced by all the detection techniques tested, at the notable exception of physical developer. The results obtained were very similar to what is generally observed with real fingermarks, and it was observed that the impact of water immersion on the artificial fingermarks was comparable as well. These findings open new perspectives for the development of multi-target quality control test strips or for the standardisation of proficiency testing and interlaboratory collaborative exercises where ground truth is crucial to guarantee comparable results and objective assessment.

The impact of substrate dampness on the transfer of glass fragments to upper garments when breaking windows.

Glass fragments are often recovered from garments worn by the authors of certain types of crimes and are useful as they present strong connections to the scene at both the source and activity level. It is known that the transfer of glass fragments is impacted when recipient garments are dampened, such as by rain, however, the details of the effect are not clear. This research aimed to determine the impact of substrate dampness on glass retention. Across the three test garments, a cotton t-shirt was found to increase in retentiveness with increasing dampness, while a wool/polyester blend jumper and a cotton hoodie were both found to increase only to a point, before decreasing again when the garment was saturated. This is attributed to the construction of the fabrics, as it does not appear to be related to the identity of the textile itself. It was also found that the size distribution of fragments changed with dampness. All the garments retained a smaller proportion of fragments less than 0.5 mm in size when saturated or dampened than when dry, along with an increase in the proportion of fragments in the 1-1.5 mm and greater than 1.5 mm size categories. These results indicate that is important to consider the impact of substrate dampening when relevant, and that this consideration must be done holistically as different substrates respond to dampening in different ways. It also indicates that consideration of the size distribution in fragment populations may reveal additional information in complex scenarios.

Quality Management in forensic science: A closer inspection.

An international survey was conducted on the benefits and limitations of accreditation to ISO17025 in forensic science, and how quality management could be improved to reflect the complexities of the end-to-end process. The survey was in response to growing concern within the forensic science community that the standard ISO17025 (and ISO17020), which is the backbone of forensic science accreditation, does not have sufficient depth and reach to properly address the quality of both the inputs (crime scene traces) and outputs (e.g., opinions in a report) of forensic science. The survey was developed around three themes: (1) fitness for purpose, (2) competences and (3) education & training. It targeted directors and senior managers, including quality managers, of forensic science laboratories/facilities. The survey was developed by the research team and disseminated with the cooperation of the International Forensic Strategic Alliance (IFSA) and six regional Networks: the American Society of Crime Laboratory Directors (ASCLD), the European Network of Forensic Science institutes (ENFSI), the Australian and New Zealand Forensic Executive Committee (ANZFEC) (formerly SMANZFL), Acadamia Iberoamericana de Criminalistica Estudios Forenses (AICEF), Asian Forensic Sciences Network (AFSN) and Southern Africa Regional Forensic Science Network (SARFS). What emerged for each of the three themes of the survey are areas of concern where the forensic science community should reconsider its approach to quality management if it is to have continuing value and relevance into the future. The results are evaluated and discussed. Briefly, the results include evidence of a lack of fitness for purpose of ISO17025 as a standard for the forensic science continuum, a lack of agreement on what forensic science is and poor levels of recognition of crime scene investigation, many competences, particularly cognitive competences, are not identified, monitored or assessed and the incentive to gain accreditation and maintain continuous improvement is intrinsic rather than customer driven.

The transfer of fibres between garments in a choreographed assault scenario.

Our fundamental understanding of fibre transfer remains based on early seminal transfer studies that were largely mechanical simulations. However, transfer events in the real world are uncontrolled in nature. This study takes a novel approach to address this discrepancy, with skilled jiu-jitsu practitioners performing a choreographed 'standard' assault scenario to investigate the transfer of fibres between a cotton T-shirt and cotton/polyester hoody. Garments were collected immediately after the scenario and examined for the number, length and zonal distribution of transferred fibres. It was observed that cotton transferred the most fibres, on average twice as many from blended hoodies than T-shirts; whilst polyester transferred the least. Shorter fibres transferred and were recovered more readily than longer fibres; however, it was more likely to recover polyester fibres> 5 mm. The number and length of fibres transferred from the attacker's garment mainly depended on the construction of the donor textile (including sheddability) and properties of the fibres. Conversely, properties of the recipient textile were more significant factors when considering transfer from the victim's garment. Location of recovered fibres was found to be dependent on the wearer's role, but generally, upper zones and sleeves of both garments were most populated. Overall, these results will contribute to grow our current knowledge base regarding fibre transfer between donor and recipient textiles in a common assault situation. This will ultimately aid experts support evaluation with regards to competing hypotheses such as in a Bayesian framework.

[The role of the cardiopulmonary exercise test and pulmonary rehabilitation in long COVID-19]. / Apports de l'exploration fonctionnelle à l'exercice et de la réhabilitation respiratoire dans le COVID long.

INTRODUCTION: Long COVID refers to persistent symptoms, lasting more than 4 weeks after acute SARS-CoV-2 infection, even though the infection itself has been successfully controlled and remedied. Patient complaints are diverse, and the underlying physiopathological mechanisms are not well understood. Dyspnea and muscle fatigue are among the most commonly reported symptoms. STATE OF THE ART: Cardiopulmonary exercise test (CPET) has been recognized as a useful tool in investigation of unexplained dyspnea. In patients with chronic lung disease, pulmonary rehabilitation is a program designed to counteract dyspnea, to increase exercise capacity and to improve quality of life. PERSPECTIVES: Publications on CPET and pulmonary rehabilitation are needed in order to deepen comprehension and enhance management of long-COVID-19. CONCLUSIONS: CPET reports have shown that symptoms persisting in the aftermath of acute SARS-CoV-2 infection may be related to deconditioning, a common occurrence after ICU stay, to cardiac dysautonomia subsequent to critical infections and, finally, to dysfunctional breathing subsequent to mild infections. These findings justify pulmonary rehabilitation, which has proven to be effective regardless of the severity of the initial infection, not only immediately after hospital discharge, but also at later points in time.

A comparison of the natural and groomed fingermark lipid composition of different donors using GC/MS.

The lipid composition of natural fingermarks was studied and compared with the composition of groomed residue. Approximately 100 specimens were collected from 6 donors over three sessions (in October, December and July) and analysed using gas chromatography / mass spectrometry (GC/MS). The measured lipid content was generally lower and more variable in natural fingermarks than in groomed fingermarks. Some significant variability was noticed. Relative standard deviations were the highest between donors (generally above 100%) but were also relatively high within donor within a session (from 21% to 80%) and between sessions (from 34% to 126%). The fingermarks from one of the donors generally contained higher relative amounts of lipids in both groomed and natural residue compared to the others. All other fingermarks led to very variable amounts and did not allow classifying the other donors as constantly "good" or "poor" donors. Squalene was the major compound in all marks, particularly in groomed specimens. A correlation between squalene, cholesterol, myristic acid, palmitoleic acid, stearyl palmitoleate and pentadecanoic acid was highlighted. Oleic and stearic were also correlated together but generally more in natural than groomed marks. The obtained results may be particularly useful to better understand the detection mechanisms for techniques targeting lipids and to develop artificial fingermark secretions to further support the development of detection techniques.

Monitoring for fentanyl within Australian supervised injecting facilities: Findings from feasibility testing of novel methods and collaborative workshops.

BACKGROUND: Australia is yet to see widespread fentanyl-contaminated heroin, despite the established presence of fentanyl in other countries. International mortality trends alongside a local cluster of fentanyl-related deaths prompted interest in developing methods to monitor for fentanyl and other potentially harmful novel psychoactive substances (NPS) in Australia. METHODS: We tested novel methods to monitor for fentanyl and other NPS. From 2017-2021, clients from supervised injecting facilities (SIFs) in Melbourne and Sydney, Australia, contributed urine screens (UDS) with BTNX Rapid Response™ fentanyl test strips (FTS) paired with surveys, and injecting equipment associated with opioid overdoses for laboratory analysis. A single site piloted drug checking using FTS with laboratory confirmation. Two workshops were conducted with SIF staff, content experts and people with lived experience to determine how results can inform practices within SIFs. RESULTS: Of the 911 UDS with FTS conducted, less than 1% (n=8) yielded positive results that were not explained by self-reported pharmaceutical fentanyl use, with two laboratory confirmed fentanyl positive results. Injecting equipment from 59 overdoses was tested and neither fentanyl nor other NPS were identified. Drug checking with FTS (n=34) indicated the presence of fentanyl on three tests. Two specimens were subsequently sent for laboratory testing and classified as false positives as the presence of fentanyl was not confirmed. Workshop participants (n=21) felt routine monitoring with FTS currently had limited value. A process for using pre-defined signals to trigger surveillance was developed. CONCLUSION: The high false positive rates with FTS, relative to the small number of positive results and potential for them to undermine confidence in FTS emphasised the need for confirmatory testing. The role of routine surveillance was unclear within the current low-fentanyl context, however, a process was developed to upscale testing should signals of increased fentanyl prevalence in the Australian heroin market emerge.

Towards more relevance in forensic science research and development.

Many different issues have been identified in forensic science for more than 10 years. While quality management has often been suggested as a path forward, research is generally considered as an essential part of the solution. Through an overview of current forensic science research, this paper aims at evaluating if and how research answer the challenges forensic science is currently facing. While forensic related publications have massively increased over the years, approximately half of the publications were published in non-forensic sources, indicating that forensic science research tends to be led by other disciplines. Over the years, forensic science research has remained largely oriented towards methodological and technological development rather than relevance to the forensic science discipline and practice. Practical implementation of the techniques is rarely discussed from a forensic perspective, and thus research rarely move from the "proof-of-concept" stage to its utilisation in case investigation. The digital transformation also generated a massive increase of data, making it challenging to find the relevant pieces of information in the mass of "forensic" publications available on-line. Thus, we propose to refocus forensic science research on forensic fundamental and practical questions to strengthen the discipline and its impact on crime investigation and security issues. Our propositions represent an incentive to further discuss forensic science research and knowledge transmission through the definition of a common culture within the community, focusing on common fundamental knowledge such as a better understanding of the concept of trace and its case-based information content.

Evaluation of long-term sequelae by cardiopulmonary exercise testing 12 months after hospitalization for severe COVID-19.

BACKGROUND: Cardiopulmonary exercise testing (CPET) is an important clinical tool that provides a global assessment of the respiratory, circulatory and metabolic responses to exercise which are not adequately reflected through the measurement of individual organ system function at rest. In the context of critical COVID-19, CPET is an ideal approach for assessing long term sequelae. METHODS: In this prospective single-center study, we performed CPET 12 months after symptom onset in 60 patients that had required intensive care unit treatment for a severe COVID-19 infection. Lung function at rest and chest computed tomography (CT) scan were also performed. RESULTS: Twelve months after severe COVID-19 pneumonia, dyspnea was the most frequently reported symptom although only a minority of patients had impaired respiratory function at rest. Mild ground-glass opacities, reticulations and bronchiectasis were the most common CT scan abnormalities. The majority of the patients (80%) had a peak O2 uptake (V'O2) considered within normal limits (median peak predicted O2 uptake (V'O2) of 98% [87.2-106.3]). Length of ICU stay remained an independent predictor of V'O2. More than half of the patients with a normal peak predicted V'O2 showed ventilatory inefficiency during exercise with an abnormal increase of physiological dead space ventilation (VD/Vt) (median VD/VT of 0.27 [0.21-0.32] at anaerobic threshold (AT) and 0.29 [0.25-0.34] at peak) and a widened median peak alveolar-arterial gradient for O2 (35.2 mmHg [31.2-44.8]. Peak PetCO2 was significantly lower in subjects with an abnormal increase of VD/Vt (p = 0.001). Impairments were more pronounced in patients with dyspnea. Peak VD/Vt values were positively correlated with peak D-Dimer plasma concentrations from blood samples collected during ICU stay (r2 = 0.12; p = 0.02) and to predicted diffusion capacity of the lung for carbon monoxide (DLCO) (r2 = - 0.15; p = 0.01). CONCLUSIONS: Twelve months after severe COVID-19 pneumonia, most of the patients had a peak V'O2 considered within normal limits but showed ventilatory inefficiency during exercise with increased dead space ventilation that was more pronounced in patients with persistent dyspnea. TRIAL REGISTRATION: NCT04519320 (19/08/2020).

Analysis of Stimulants in Sweat and Urine Using Disposable Pipette Extraction and Gas Chromatography Coupled to Mass Spectrometry in the Context of Doping Control.

Urine is initially collected from athletes to screen for the presence of illicit drugs. Sweat is an alternative sample matrix that provides advantages over urine including reduced opportunity for sample adulteration, longer detection-time window and non-invasive collection. Sweat is suitable for analysis of the parent drug and metabolites. In this study, a method was developed and validated to determine the presence of 13 amphetamine- and cocaine-related substances and their metabolites in sweat and urine using disposable pipette extraction (DPX) by gas chromatography coupled to mass spectrometry. The DPX extraction was performed using 0.1 M HCl and dichloromethane:isopropanol:ammonium hydroxide (78:20:2, v/v/v) followed by derivatization with N-methyl-N-(trimethylsilyl) trifluoroacetamide at 90°C for 20 min. DPX extraction efficiencies ranged between 65.0% and 96.0% in urine and 68.0% and 101.0% in sweat. Method accuracy was from 90.0% to 104.0% in urine and from 89.0% to 105.0% in sweat. Intra-assay precision in urine and in sweat were <15.6% and <17.8%, respectively, and inter-assay precision ranged from 4.70% to 15.3% in urine and from 4.05% to 15.4% in sweat. Calibration curves presented a correlation coefficient -0.99 for all analytes in both matrices. The validated method was applied to urine and sweat samples collected from 40 professional athletes who knowingly took one or more of the target illicit drugs. Thirteen of 40 athletes were positive for at least one drug. All the drugs detected in the urine were also detected in sweat samples indicating that sweat is a viable matrix for screening or confirmatory drug testing.

Prevalence and Characteristics of Sleep Apnea in Intensive Care Unit Survivors After SARS-CoV-2 Pneumonia.

Background: Sleep apnea (SA) was reported as possibly exacerbating symptoms of COVID-19, a disease induced by SARS-CoV-2 virus. The same comorbidities are common with both pathologies. This study aimed to estimate the prevalence, characteristics of SA and variation in AHI three months after severe COVID-19 requiring intensive care unit (ICU) admission. Methods: A prospective cohort of patients admitted to ICU for severe COVID-19 underwent an overnight home polygraphy 3 months after onset of symptoms, as part of a comprehensive follow-up program (pulmonary function tests, 6-minute walk tests and chest CT-scan). Patients with an apnea hypopnea index (AHI) ≥5 were considered as having SA. We performed a comparative descriptive analysis of 2 subgroups according to the existence, severity of SA and indication for effective SA treatment: patients with absent or mild SA (AHI <15) vs patients with moderate to severe SA (AHI ≥15). Results: Among 68 patients included, 62 (91%) had known comorbidities (34 hypertension, 21 obesity, 20 dyslipidemia, 16 type 2 diabetes). It has been observed a preexisting SA for 13 patients (19.1%). At 3 months, 62 patients (91%) had SA with 85.5% of obstructive events. Twenty-four patients had no or a mild SA (AHI <15) and 44 had moderate to severe SA (AHI ≥15). Ischemic heart disease exclusively affected the moderate to severe SA group. Except for thoracic CT-scan which revealed less honeycomb lesions, COVID-19 symptoms were more severe in the group with moderate to severe SA, requiring a longer curarization, more prone position sessions and more frequent tracheotomy. Conclusion: SA involved 91% of patients in our population at 3 months of severe COVID-19 and was mainly obstructive type. Although SA might be a risk factor as well as consequences of ICU care in severe COVID-19 infection, our results underline the importance of sleep explorations after an ICU stay for this disease.

Result of one-year, prospective follow-up of intensive care unit survivors after SARS-CoV-2 pneumonia.

INTRODUCTION: Survivors of viral ARDS are at risk of long-term physical, functional and neuropsychological complications resulting from the lung injury itself, but also from potential multiorgan dysfunction, and the long stay in the intensive care unit (ICU). Recovery profiles after severe SARS-CoV-2 pneumonia in intensive care unit survivors have yet to be clearly defined. MATERIAL AND METHODS: The goal of this single-center, prospective, observational study was to systematically evaluate pulmonary and extrapulmonary function at 12 months after a stay in the ICU, in a prospectively identified cohort of patients who survived SARS-CoV-2 pneumonia. Eligible patients were assessed at 3, 6 and 12 months after onset of SARS-CoV-2. Patients underwent physical examination, pulmonary function testing, chest computed tomography (CT) scan, a standardized six-minute walk test with continuous oximetry, overnight home respiratory polygraphy and have completed quality of life questionnaire. The primary endpoint was alteration of the alveolar-capillary barrier compared to reference values as measured by DLCO, at 12 months after onset of SARS-CoV-2 symptoms. RESULTS: In total, 85 patients (median age 68.4 years, (interquartile range [IQR] = 60.1-72.9 years), 78.8% male) participated in the trial. The median length of hospital stay was 44 days (IQR: 20-60) including 17 days in ICU (IQR: 11-26). Pulmonary function tests were completed at 3 months (n = 85), 6 months (n = 80), and 12 months (n = 73) after onset of symptoms. Most patients showed an improvement in DLCO at each timepoint (3, 6, and 12 months). All patients who normalized their DLCO did not subsequently deteriorate, except one. Chest CT scans were abnormal in 77 patients (96.3%) at 3 months and although the proportion was the same at 12 months, but patterns have changed. CONCLUSION: We report the results of a comprehensive evaluation of 85 patients admitted to the ICU for SARS-CoV-2, at one-year follow-up after symptom onset. We show that most patients had an improvement in DLCO at each timepoint. TRIAL REGISTRATION: Clinical trial registration number: NCT04519320.

An application example of the likelihood ratio approach to the evaluation of organic gunshot residues using a fictional scenario and recently published data.

The analysis of gunshot residues (GSR) can provide important information with regard to the involvement of a person of interest (POI) in a firearm-related incident. Organic gunshot residues (OGSR) have been investigated in order to provide additional and complementary information to the traditional inorganic gunshot residue (IGSR) particles detected by scanning electron microscopy (SEM). Currently, many procedures and analytical methods have been developed to detect OGSR-related compounds collected from the shooter's hands. However, such studies provide no information regarding the inclusion of such results in an activity level evaluation for discharging a firearm. The aim of this article is to assess the feasibility of using the likelihood ratio (LR) approach as a tool to evaluate OGSR results for activity level propositions. The developed model focuses on the assignment of an LR for several compounds detected in OGSR. A simple worst-case simulation was investigated in order to assess the applicability of the LR approach to evaluate OGSR traces. This simulation highlighted the importance of addressing an appropriate pair of activity level propositions when evaluating the results.

Latent fingermark detection using functionalised silicon oxide nanoparticles: Investigation into novel application procedures.

Investigations into the application of carboxyl-functionalised silicon oxide nanoparticles doped with a ruthenium complex (RuBpy-doped CES-SiO2 NPs) for latent fingermark development on non-porous surfaces were reported in previous studies. These studies suggested that an optimised NP-based method demonstrated advantages in fingermark selectivity and sensitivity. To continue the series of research into using RuBpy-doped CES-SiO2 NPs for fingermark detection, the versatility and overall practicality of the optimised SiO2 NP-based reagent for latent fingermark detection and enhancement was evaluated. When the optimised NP-based method was used in a repeated fashion (application of multiple NP treatment cycles), it was found that the overall fingermark detection quality increased across the evaluated fingermarks without a high risk of overdevelopment. The possibility of incorporating the optimised NP-based reagent for potential operational use (e.g., at crime scenes) was successfully demonstrated via spray application on three test surfaces (aluminium foil, transparent polypropylene film and green polyethylene film). It was also shown that further enhancement of "spray-detected" fingermarks was achievable via subsequent treatment using the NP-based reagent in a colloidal dispersion bath. Additionally, the compatibility of the optimised NP-based method with two-step cyanoacrylate fuming for latent fingermark detection was evaluated. It was concluded that the two techniques are not compatible for application in a fingermark detection sequence. While encouraging results were demonstrated in this study, further optimisation and comparison will be required before the multiple-treatment and spray-treatment approaches can be considered for operational implementation.

Infrequent detection of unintentional fentanyl use via urinalysis among people who regularly inject opioids in Sydney and Melbourne, Australia.

BACKGROUND AND AIM: The current phase of the North American 'opioid crisis' is characterised by illicit fentanyl use; however, the presence of illicit fentanyl in Australia is unknown. This study aimed to monitor unintentional fentanyl consumption in Australia. DESIGN: Rapid urine drug screens (UDS) paired with surveys conducted within supervised injecting facilities (SIFs) and confirmatory laboratory testing. SETTING: Sydney and Melbourne, Australia. PARTICIPANTS: Clients who used heroin within the past 2 days (n = 911 tests, 2017-2021). Participants were demographically similar to the overall client base (median age 43, 72% male). MEASUREMENTS: UDS were conducted using BTNX Rapid Response fentanyl urine strip tests with cross-reactivity to numerous fentanyl analogues. Positive urine samples were analysed using liquid chromatography coupled with tandem mass spectrometry. Surveys covered past 3 day drug use and lifetime report of fentanyl in heroin. FINDINGS: Two percent of participants reported intentional use of fentanyl, mostly through fentanyl patches. Of the 911 rapid UDS conducted, 17 (1.9%) yielded positive results. Eight of these (all from Melbourne) were not explained by survey-reported fentanyl use in the past 3 days. Of these 8 unexplained positives, confirmatory laboratory analysis was conducted on 6, with 4 deemed to be false positives, and 2 confirmed for the presence of fentanyl. This represents the first confirmation of unintended use of fentanyl type substances in this population. CONCLUSION: There is limited evidence of unintentional fentanyl use among people in Sydney and Melbourne, Australia who regularly inject heroin, suggesting that, currently, there is very little illicit fentanyl in Australian drug markets accessed by supervised injecting facilities attendees. This study demonstrates the feasibility of quick onsite testing to cost-effectively screen large samples for fentanyl; however, the high false positive rate emphasises the need for confirmation of positive tests through advanced analytical techniques.

Production of artificial fingermarks. Part I - Synthetic secretions formulation.

Fingermark variability is a critical parameter. To mitigate the effects of this variability, synthetic secretions in the form of simple mixtures of target compounds found in eccrine sweat have been described in the literature, but they are usually reactive towards only a minimal range of detection techniques. If this approach is acceptable for the production of single-technique test strips, such artificial secretions cannot be considered as reliable fingermark simulants because they do not reproduce the complex matrix that makes up real secretions. Research has shown that sebaceous and eccrine compounds are probably present simultaneously in fingermark residue in the form of an emulsion. This paper is the first part of a research project that aims at producing realistic artificial fingermarks containing an extensive range of eccrine and sebaceous compounds. This first study aimed to reproduce and compare two synthetic fingermark residues formulations and assess their potential to be used as fingermark simulants. Spot tests of the artificial secretions were deposited on paper substrates, and their reactivity with four common detection techniques was tested: 1,2-indanedione-zinc, ninhydrin, oil red O, and physical developer. Both formulations showed very good results when processed with the two amino acid reagents, as well as oil red O, and no obvious differences were observed between the two versions. The results obtained with the physical developer were inconsistent and demonstrated that the fundamental working principle of physical developer needs to be further understood. The results were extremely promising as they showed the potential of such reproducible artificial secretions to be used to assess an extensive range of detection techniques, which would be highly beneficial to guarantee better research and quality control in fingermark detection. The use of spot tests to deposit the simulant was shown to be unreliable and a more controllable and reproducible deposition method using an inkjet printer will be presented in the second part of this research.