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Forensic DNA analysis of cartridges and fired cartridge casings remains challenging, possibly due to the heat and pressure generated during firing of the weapon as well as metal ions from the casings that have been suggested to initiate DNA degradation and inhibit PCR during the DNA profiling process. Even though recently developed DNA recovery protocols have shown to significantly improve DNA yields and DNA profile success rates no information is available on whether the time interval between contact and the DNA recovery process has an influence on these outcomes. In the current study 40 cartridges and 40 fired cartridge casings were left untreated for 24 h or 1 week after which the rinse-and-swab technique was used to collect DNA. Higher DNA yields and higher DNA profile success rates were obtained from cartridges compared to fired cartridge casings. The same general observation was made when cartridges and fired cartridge casings were processed after 24 h compared to after 1 week. In addition, DNA profiles suitable for comparison could still be generated from samples when real-time PCR quantification indicated DNA concentrations < 0.001 ng/μl, suggesting that quantification results may not be reliable when assessing the presence of DNA on such items. In conclusion, the results indicate that cartridges and fired cartridge casings should be processed for DNA profiling as soon as possible and that DNA quantification results should be interpreted with caution as DNA profiles suitable for comparison could be missed. •Swabs with their containers can be used to safely collect and transport fired 9▒mm cartridge casings•DNA yield and the quality of DNA profiles is significantly influenced by time after manipulation of cartridges and fired cartridge casings•Lower DNA yields and lower quality DNA profiles were obtained from fired cartridge casings•DNA profiles should always be produced even if quantification indicates a DNA concentration of < 0.001 ng/μl is present

•Grain-loaded cartridges cause much wider distribution than lead pellet cartridges.•Satellite entry holes were detected in all shots from 50cm distance.•Chokes did not affect the distribution in most of the shots at same distances. Commercial grain-loaded cartridges for shotguns have been recently associated with injuries and fatalities. These cartridges are generally used as a scare gun for large animals, with a little probability of causing harm. Almost all grain-loaded cartridges contain one type of cereal grain, such as bulgur wheat, wheat or vetch seed, instead of lead pellets. Our study aimed to investigate the shot range estimation of grain-loaded cartridges and assess the variations from conventional lead pellet cartridges. In this study, eight different brands of grain-loaded cartridges were used. The inspections and measurements were made with cartridges that contain cereal grains, gunpowder and wads. Shots were made from 50, 100, 200, 300, 500cm with modified and improved cylinder chokes. Diameter of grain distribution patterns on targets were measured. These measurements were evaluated statistically considering brand, choke and distance variables. Both satellite entry holes and central entry holes were detected in all shots that were fired from 50cm distance. The smallest average diameter of grain distribution pattern between 8 different brands were measured as 14.3, 38.3, 58.5 and 83.4cm for 100, 200, 300 and 500cm respectively with modified choke. Gathered data from this study was compared with the studies conducted with conventional cartridges and differences were determined. It was detected that the grain-loaded cartridges showed much wider distribution on targets at the same shooting distance with the same and similar barrel lengths and choke values compared to conventional lead pellet containing cartridges.

In order to solve the cartridge extraction problem of cased telescoped ammunitions, a study was conducted on the dynamic process of cartridge during launching. The finite element simulation model is established firstly to analyse the mechanical properties of the cartridge during launching. Then the radial residual deformation and cartridge extraction force of the cartridge after chamber pressure unloading were obtained. Meanwhile, the effect of different yield limits of cartridge materials on the extraction performance was studied. The results show that as the yield limit of the cartridge increases, the maximum radial residual deformation first increases and then gradually decreases after unloading the chamber pressure, and the extraction force of the cartridge also shows the same trend. When the yield limit of the cartridge is greater than 1040 MPa, the extraction force goes to zero after pressure unloading, and the cartridge can be easily extracted.

The COVID-19 pandemic provides an urgent example where a gap exists between availability of state-of-the-art diagnostics and current needs. As assay protocols and primer sequences become widely known, many laboratories perform diagnostic tests using methods such as RT-PCR or reverse transcription loop mediated isothermal amplification (RT-LAMP). Here, we report an RT-LAMP isothermal assay for the detection of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) virus and demonstrate the assay on clinical samples using a simple and accessible point-of-care (POC) instrument. We characterized the assay by dipping swabs into synthetic nasal fluid spiked with the virus, moving the swab to viral transport medium (VTM), and sampling a volume of the VTM to perform the RT-LAMP assay without an RNA extraction kit. The assay has a limit of detection (LOD) of 50 RNA copies per μL in the VTM solution within 30 min. We further demonstrate our assay by detecting SARS-CoV-2 viruses from 20 clinical samples. Finally, we demonstrate a portable and real-time POC device to detect SARS-CoV-2 from VTM samples using an additively manufactured three-dimensional cartridge and a smartphone-based reader. The POC system was tested using 10 clinical samples, and was able to detect SARS-CoV-2 from these clinical samples by distinguishing positive samples from negative samples after 30 min. The POC tests are in complete agreement with RT-PCR controls. This work demonstrates an alternative pathway for SARS-CoV-2 diagnostics that does not require conventional laboratory infrastructure, in settings where diagnosis is required at the point of sample collection.

Electronic cigarettes (e-cigarettes) are becoming increasingly popular with smokers worldwide. Users report buying them to help quit smoking, to reduce cigarette consumption, to relieve tobacco withdrawal symptoms, and to continue having a 'smoking' experience, but with reduced health risks. Research on e-cigarettes is urgently needed in order to ensure that the decisions of regulators, healthcare providers and consumers are based on science. Methods ECLAT is a prospective 12-month randomized, controlled trial that evaluates smoking reduction/abstinence in 300 smokers not intending to quit experimenting two different nicotine strengths of a popular e-cigarette model ('Categoria'; Arbi Group Srl, Italy) compared to its non-nicotine choice. GroupA (n = 100) received 7.2 mg nicotine cartridges for 12 weeks; GroupB (n = 100), a 6-week 7.2 mg nicotine cartridges followed by a further 6-week 5.4 mg nicotine cartridges; GroupC (n = 100) received no-nicotine cartridges for 12 weeks. The study consisted of nine visits during which cig/day use and exhaled carbon monoxide (eCO) levels were measured. Smoking reduction and abstinence rates were calculated. Adverse events and product preferences were also reviewed. Declines in cig/day use and eCO levels were observed at each study visits in all three study groups (p<0.001 vs baseline), with no consistent differences among study groups. Smoking reduction was documented in 22.3% and 10.3% at week-12 and week-52 respectively. Complete abstinence from tobacco smoking was documented in 10.7% and 8.7% at week-12 and week-52 respectively. A substantial decrease in adverse events from baseline was observed and withdrawal symptoms were infrequently reported during the study. Participants' perception and acceptance of the product under investigation was satisfactory. In smokers not intending to quit, the use of e-cigarettes, with or without nicotine, decreased cigarette consumption and elicited enduring tobacco abstinence without causing significant side effects. ClinicalTrials.gov NCT01164072 NCT01164072.

To study the influence of the cartridge adapter on the initial disturbance of the rocket shell launch, the dynamic simulation model of the interaction between the cartridge and the storage and distribution box during the rocket shell launch is established. With the aim of reducing the initial disturbance, the structure optimization and design parameters of the cartridge adapter are obtained fro m the dynamics simulation optimization analysis of rocket shell launch. The optimization results suggest that the number and layout of the cartridge adapter can greatly reduce the initial disturbance to launch and the optimization of cartridge adapter can greatly reduce the initial disturbance to rocket shell. The optimization method and results can provide reference for the design of rocket shell.

•A sample set of cartridge cases was collected from various people firing the same gun and ammunition.•A proposed method used the statistical data from the sample set to estimate a shooter’s position from ejected cartridge cases.•It was found that with an increasing number of cartridge cases used for shooter position estimation, the errors and standard deviation decreased, improving estimation results. Ejected cartridge cases in shooting incidents are useful in crime scene reconstruction to approximate the location of a shooter and the dynamics of an encounter. The purpose of this study is to propose a method to approximate a shooter’s position based on a reference sample set of cartridge case ejection patterns. This research is significant as there are no blind studies that determine the precision or errors when estimating a shooter’s position based on cartridge case ejection patterns. Understanding the errors associated with shooter position estimation may give investigators a standardized method for establishing a reference set of cartridge cases which reflect the behavior of ejection patterns under controlled variables, while having a more reliable method when estimating a shooter’s position. A reference sample set of more than 312 cartridge cases was collected from various people firing the same gun and ammunition from a known position and at different heights using a double-handed grip. The proposed method used the statistical data from the reference sample set and was tested on blind data sets to determine the errors and precision using “unknown” shooters. The blind testing sets ranged between 1 and 6 ejected cartridge cases with a known direction of fire. It was found that with an increasing number of cartridge cases used for shooter position estimation, the errors and standard deviation decreased, improving estimation results. With a blind set of 6 cartridge cases, the errors were shown to average 122 cm from the known firing position. The applicability of this method depends significantly on the type of firearm, ammunition, human factors, environment and other factors.

Firearm identification plays a crucial role in criminal justice globally. The capability to link firearms to specific crimes is invaluable for investigations and court cases. Each firearm leaves distinctive markings on bullets and cartridge cases, creating a “mechanical fingerprint” that can be used for the comparison of bullets and cartridge cases and underpins this area of forensic science. Cartridge cases fired from the same firearm exhibit similar markings on their bases. These traces can be used for investigation purposes as a means to potentially provide a link between more than one scene where cartridge cases have been recovered, or to provide a potential evidential link between a firearm and a cartridge case. These applications involve comparing the markings on the base of two or more cartridge cases, consisting of the headstamp, breech face and firing pin areas. The headstamp area usually contains information about the manufacturer and the calibre. Once this is considered, the remaining task is to compare the breech and firing pin areas of the two cartridges. Currently, some automated methods exist for this comparison, all of which involve the removal of the headstamp area to minimize bias. Some semi-automated methods for headstamp removal are available, and recently, an automated deep learning method that can be applied to 256 × 256 pixel resolution images has been introduced. In this article, we also propose a deep learning method addressing a more computationally demanding task of removing the head stamp area in higher-resolution images, 512 × 512 and 2592 × 1944 pixels, which will permit the automated extraction of finer features at a higher resolution. We also (a) introduce a post-processing method that improves the performance of our method, (b) provide the labelled data that we have produced so it can be used, together with the NIST database of cartridge case images, as a benchmark for future research, and (c) provide the estimated weights and models of the convolutional neural networks that can either be used directly or as initial values for further research. This article contributes to the emerging body of research on deep learning applications in forensic science. •The only article addressing segmentation of cartridge cases at 512 × 512 resolution.•Three CNNs tested for cartridge-case segmentation: UNet, Dense UNet and DeepLabv3+.•Deeplabv3+ performs well for segmenting cartridge case images.•Upsampling predicted masks from DeepLabv3+ to 2592 × 1944 maintains accuracy.•Postprocessing was used to remove small artefacts after segmentation.

The firing pin impression left on the base of a cartridge case is a critical analytical feature in forensic science. To address the limitations of traditional manual trace analysis and mitigate the risk of secondary damage to physical evidence, we employ a line laser displacement sensor to capture and analyze three-dimensional (3D) traces of fired cartridge cases. However, when using laser displacement sensors to collect traces from metal cartridge cases, the high curvature and reflectivity of the metal surface can cause specular reflections, potentially leading to measurement anomalies in the firing pin impressions. To effectively identify these anomalies during automated trace analysis, this paper proposes an automated detection method. This method extends the gray-level co-occurrence matrix (GLCM), which is traditionally used for two-dimensional (2D) images, to the 3D scenarios, enabling the extraction of texture features from the 3D traces of cartridge cases. A support vector machine (SVM) is then employed to detect and classify measurement anomalies. Experiments with 2038 sets of firing pin impression data from cartridge cases demonstrated a detection accuracy of 98.92 %, validating the effectiveness of the proposed method. We hope this method can be widely adopted in forensic laboratories to improve the reliability of evidence analysis. •Extend 2D GLCM to three-dimensional scenarios and apply it to anomaly detection in cartridge case measurements.•A measurement anomaly detection method based on 3D GLCM is proposed to address industry challenges in the forensic field.•A self-built 3D trace collection device was used to collect a dataset of 2038 samples, validating performance in real-world scenarios.

E-cigarettes are promoted as healthier alternatives to conventional cigarettes. Many cigarette smokers use both products. It is unknown whether the additional use of e-cigarettes among cigarette smokers (dual users) is associated with reduced exposure to tobacco-related health risks. Cross-sectional analysis was performed using baseline data from the Health eHeart Study, among English-speaking adults, mostly from the United States. Cigarette use (# cigarettes/day) and/or e-cigarette use (# days, # cartridges, and # puffs) were compared between cigarette only users vs. dual users. Additionally, we examined cardiopulmonary symptoms/ conditions across product use: no product (neither), e-cigarettes only, cigarettes only, and dual use. Among 39,747 participants, 573 (1.4%) reported e-cigarette only use, 1,693 (4.3%) reported cigarette only use, and 514 (1.3%) dual use. Dual users, compared to cigarette only users, reported a greater median (IQR) number of cigarettes per day, 10.0 (4.0-20.0) vs. 9.0 (3.0-15.0) (p < .0001), a lower (worse) median (IQR) SF-12 general health score, 3.3 (2.8-3.8) vs. 3.5 (2.8-3.9) (p = .0014), and a higher (worse) median (IQR) breathing difficulty score in the past month, 2.0 (1.0-2.0) vs. 1.0 (1.0-2.0) (p = .001). Of the 19 cardiopulmonary symptoms/ conditions, having a history of arrhythmia was significantly different between cigarette only users (14.2%) and dual users (17.8%) (p = .02). In this sample, dual use was not associated with reduced exposure to either (i) cigarettes, compared to cigarette only users or (ii) e-cigarettes, compared to e-cigarette only users. E-cigarette only use, compared to no product use, was associated with lower general health scores, higher breathing difficulty scores (typically and past month), and greater proportions of those who responded 'yes' to having chest pain, palpitations, coronary heart disease, arrhythmia, COPD, and asthma. These data suggest the added use of e-cigarettes alone may have contributed to cardiopulmonary health risks particularly respiratory health risks.