‘Synthetic cannabis’: A dangerous misnomer

The term 'synthetic cannabis' has been widely used in public discourse to refer to a group of cannabinoid receptor agonists. In this paper we detail the characteristics of these drugs, and present the case that the term is a misnomer. We describe the pharmacodynamics of these drugs, their epidemiology, mechanisms of action, physiological effects and how these differ substantially from delta-9-tetrahydrocannabinol (THC). We argue that not only is the term a misnomer, but it is one with negative clinical and public health implications. Rather, the substances referred to as 'synthetic cannabis' in public discourse should instead be referred to consistently as synthetic cannabinoid receptor agonists (SCRAs), a drug class distinct from plant-derived cannabinoids. SCRAs have greater potency and efficacy, and psychostimulant-like properties. While such terminology may be used in the scientific community, it is not widely used amongst the media, general public, people who use these drugs or may potentially do so. A new terminology has the potential to reduce the confusion and harms that result from the misnomer ‘synthetic cannabis’. The constant evolution of this distinct drug class necessitates a range of distinct policy responses relating to terminology, harm reduction, epidemiology, treatment, and legal status

Characteristics and circumstances of death related to the self-administration of ketamine

Background and aims: Ketamine is used for anaesthesia, sedation and the treatment of mood disorders, but is also widely used for non-medical purposes. This study aimed to: (1) determine the characteristics and circumstances of all recorded cases of self-administered ketamine-related death in Australia, 2000–19 and (2) determine the toxicology and major organ pathology of cases. Design: Retrospective study of all Australian cases in which self-administered ketamine was a mechanism contributory to death, retrieved from the National Coronial Information System. Setting: Australia-wide. Cases: Sixty-eight cases, with a mean age of 35.2 years (standard deviation = 11.5, range = 16–63), 76.5% male. Measurements: Information was collected on cause of death, demographics, circumstances of death, toxicology and major organ pathology. Findings: Death was attributed to toxicity in 82.3% of cases (accidental, 58.8%; deliberate, 23.5%), suicide by violent means (8.8%) and traumatic accident (8.8%). In six cases the decedent had been prescribed ketamine. In 32.4% the final route of ketamine administration was by injection. The fatal incident predominantly occurred in a private environment (72.1%). Ketamine was present in the blood of 90.1% and other biomarkers in the remainder. The median blood ketamine concentration was 0.2 mg/l (0.02–6.9 mg/l). Other drugs were detected in 95.5% of cases: opioids (59.1%), hypnosedatives (57.6%), psychostimulants (50.0%), alcohol (27.3%), Δ-9-tetrahydrocannabinol (18.2%), antidepressants (28.8%) and antipsychotics (9.1%). Pulmonary oedema was present in 82.2% of cases that underwent autopsy and pneumonia in 26.7%. Conclusions: The typical case of self-administered ketamine-related death in Australia, 2000–19, was a male in his mid-30s who had used multiple drugs, with the fatal incident most commonly occurring in a private setting. Death due to accidental drug toxicity was the most common manner of death, but suicide was highly prevalent

Characteristics and circumstances of death related to gamma hydroxybutyrate (GHB)

Introduction: Gamma hydroxybutyrate (GHB) has gained substantial popularity as an illicit recreational drug. The current study aimed to: (1) determine the characteristics and circumstances of death of all recorded cases of GHB-related death in Australia, 2001–2019; (2) determine the toxicology of cases; and (3) determine major organ pathology. Methods: Retrospective study of all Australian cases in which GHB was a mechanism contributory to death retrieved from the National Coronial Information System (n = 74). Information was collected on cause of death, demographics, circumstances of death, toxicology and major organ pathology. Results: The mean age was 31.5 years and 70.3% were male. The predominant circumstance of death was accidental drug toxicity (79.7%), including five cases attributed to a combination of toxicity and natural disease. Other deaths were due to trauma (12.2%) and suicide (8.2%). The fatal incident overwhelmingly occurred in a home environment (82.4%). In all cases, GHB was consumed orally. The median GHB blood concentration was 210 mg/L (range 13–1350 mg/L), and was significantly higher in toxicity cases than others (258 vs. 98 mg/L, p <.01). Other substances were present in 92.2%, most commonly psychostimulants (64.1%), hypnosedatives (28.2%) and alcohol (20.3%). Resuscitation was attempted in 20.3% of cases. Acute pneumonia (36.7%) and aspiration of vomitus (30.6%) were common. Conclusions: The typical case was a young male, who swallowed GHB and used it with other substances, most commonly at home. While acute drug toxicity was the most common cause of death, there was a substantial minority due to trauma or suicide

Metal forming progress since 2000

Considerable changes have occurred in metal forming in the last decade. A record of these changes can be found in keynote papers presented by the members of the Scientific Technical Committee-Forming, at the CIRP Annual General Meeting each year. The keynote papers are excellent references on important developments in metal forming and are used as a reference, globally. Not only is this paper a compendium of most of the keynotes presented, but from 2001 onward, it has updates on new information on five keynote subject areas. The authors of each keynote have written an update with new information that has developed since the writing of the keynote. The authors of each section are shown in order of presentation. \'02 2008 CIRP

Prevalence and Characteristics Associated with Chronic Noncancer Pain in Suicide Decedents: A National Study

Objective: The aims were to estimate the prevalence of CNCP in suicide decedents, and compare sociodemographic and clinical characteristics of people who die by suicide (i) with and without a history of CNCP and (ii) among decedents with CNCP who are younger (<65 years) and older (65 + years). Method: We examined all closed cases of intentional deaths in Australia in 2014, utilizing the National Coronial Information System. Results: We identified 2,590 closed cases of intentional deaths in Australia in 2014 in decedents over 18 years of age. CNCP was identified in 14.6% of cases. Decedents with CNCP were more likely to be older, have more mental health and physical health problems, and fewer relationship problems, and were more likely to die by poisoning from drugs, compared with decedents without CNCP. Comparisons of older and younger decedents with CNCP found that compared to younger (<65 years) decedents with CNCP, older decedents (65 + years) were less likely to have mental health problems. Conclusions: This is the first national study to examine the characteristics of suicide deaths with a focus on people with CNCP. Primary care physicians should be aware of the increased risk for suicide in people living with CNCP, and it may be useful for clinicians to screen for CNCP among those presenting with suicidal behaviors

Forming limit predictions for single-point incremental sheet metal forming

peer reviewedA characteristic of incremental sheet metal forming is that much higher deformations can be achieved than conventional forming limits. In this paper it is investigated to which extent the highly non-monotonic strain paths during such a process may be responsible for this high formability. A Marciniak-Kuczynski (MK) model is used to predict the onset of necking of a sheet subjected to the strain paths obtained by finite-element simulations. The predicted forming limits are considerably higher than for monotonic loading, but still lower than the experimental ones. This discrepancy is attributed to the strain gradient over the sheet thickness, which is not taken into account in the currently used MK model

Mechanism investigation of friction-related effects in single point incremental forming using a developed oblique roller-ball tool

Single point incremental forming (SPIF) is a highly versatile and flexible process for rapid manufacturing of complex sheet metal parts. In the SPIF process, a ball nose tool moves along a predefined tool path to form the sheet to desired shapes. Due to its unique ability in local deformation of sheet metal, the friction condition between the tool and sheet plays a significant role in material deformation. The effects of friction on surface finish, forming load, material deformation and formability are studied using a newly developed oblique roller ball (ORB) tool. Four grades of aluminum sheet including AA1100, AA2024, AA5052 and AA6111 are employed in the experiments. The material deformation under both the ORB tool and conventional rigid tool are studied by drilling a small hole in the sheet. The experimental results suggest that by reducing the friction resistance using the ORB tool, better surface quality, reduced forming load, smaller through-the-thickness-shear and higher formability can be achieved. To obtain a better understanding of the frictional effect, an analytical model is developed based on the analysis of the stress state in the SPIF deformation zone. Using the developed model, an explicit relationship between the stress state and forming parameters is established. The experimental observations are in good agreement with the developed model. The model can also be used to explain two contrary effects of friction and corresponding through-the-thickness-shear: increase of friction would potentially enhance the forming stability and suppress the necking; however, increase of friction would also increase the stress triaxiality and decrease the formability. The final role of the friction effect depends on the significance of each effect in SPIF process

Effect of FEM choices in the modelling of incremental forming of aluminium sheets

peer reviewedThis paper investigates the process of single point incremental forming of an aluminium cone with a 50-degree wall angle. Finite element (FE) models are established to simulate the process. Different FE packages have been used. Various aspects associated with the numerical choices as well as the material and process parameters have been studied. The final geometry and the reaction forces are presented as the results of the simulations. Comparison between the simulation results and the experimental data is also made

Characterization of shape and dimensional accuracy of incrementally formed titanium sheet parts with intermediate curvatures between two feature types

Single point incremental forming (SPIF) is a relatively new manufacturing process that has been recently used to form medical grade titanium sheets for implant devices. However, one limitation of the SPIF process may be characterized by dimensional inaccuracies of the final part as compared with the original designed part model. Elimination of these inaccuracies is critical to forming medical implants to meet required tolerances. Prior work on accuracy characterization has shown that feature behavior is important in predicting accuracy. In this study, a set of basic geometric shapes consisting of ruled and freeform features were formed using SPIF to characterize the dimensional inaccuracies of grade 1 titanium sheet parts. Response surface functions using multivariate adaptive regression splines (MARS) are then generated to model the deviations at individual vertices of the STL model of the part as a function of geometric shape parameters such as curvature, depth, distance to feature borders, wall angle, etc. The generated response functions are further used to predict dimensional deviations in a specific clinical implant case where the curvatures in the part lie between that of ruled features and freeform features. It is shown that a mixed-MARS response surface model using a weighted average of the ruled and freeform surface models can be used for such a case to improve the mean prediction accuracy within ±0.5 mm. The predicted deviations show a reasonable match with the actual formed shape for the implant case and are used to generate optimized tool paths for minimized shape and dimensional inaccuracy. Further, an implant part is then made using the accuracy characterization functions for improved accuracy. The results show an improvement in shape and dimensional accuracy of incrementally formed titanium medical implants