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Chronic cannabis use is maintained in part through dysregulated stress and reward response systems. Specifically, stress-related negative affect is thought to act as a salient motivator for chronic substance use. Models of addiction posit that the transition from positive to negative reinforcement motives for substance use is a key mechanism of disordered use. However, research in substance-using samples has not assessed stress-related neural processing of both positive and negative reinforcement.Therefore, the present study utilized laboratory stress induction to examine how stress affects the reward positivity, an event-related potential sensitive to both positive (RewP) and negative (relief-RewP) reinforcement, in 87 cannabis users (58.10% female,Findings indicated that CUD severity was not associated with RewP/relief-RewP amplitude regardless of acute stress. Exploratory analyses revealed, however, that among those with history of TBI +, CUD severity was associated with greater stress-elicited blunting of the RewP and enhancement of the relief-RewP.Although initial findings contradict current allostatic models of addiction, exploratory findings suggest that history of TBI, and potentially other confounding variables related to increased risk of TBI experience, may influence the extent to which stressful experiences modulate the neurophysiology of both positive and negative reinforcement reward processing in CUD. (PsycInfo Database Record (c) 2022 APA, all rights reserved).

The climate change crisis demands a wholesale transformation of law. In this article, we consider one potential component of that transformation: the role that rights-protective statutory interpretation might play. Specifically, we analyse the transformative potential of the principle of legality. The principle of legality is a presumption of statutory interpretation that legislation should not be read as infringing fundamental common law rights in the absence of irresistibly clear statutory language. It enables courts to give statutory words their least rights-infringing meaning. The law in international fora and domestic jurisdictions now acknowledges that climate change will adversely affect human rights. We make the linkage between climate change, fundamental rights, and statutory interpretation and argue that the principle of legality may, in appropriate cases, be used to interpret legislation regulating the range of human activity, in a climate-protective way.

Water present on early Mars is often assumed to have been habitable. In this study, experiments were performed to investigate the habitability of well-defined putative martian fluids and to identify the accompanying potential formation of biosignatures. Simulated martian environments were developed by combining martian fluid and regolith simulants based on the chemistry of the Rocknest sand shadow at Gale Crater. The simulated chemical environment was inoculated with terrestrial anoxic sediment from the Pyefleet mudflats (United Kingdom). These enrichments were cultured for 28 days and subsequently subcultured seven times to ensure that the microbial community was solely grown on the defined, simulated chemistry. The impact of the simulated chemistries on the microbial community was assessed by cell counts and sequencing of 16S rRNA gene profiles. Associated changes to the fluid and precipitate chemistries were established by using ICP-OES, IC, FTIR, and NIR. The fluids were confirmed as habitable, with the enriched microbial community showing a reduction in abundance and diversity over multiple subcultures relating to the selection of specific metabolic groups. The final community comprised sulfate-reducing, acetogenic, and other anaerobic and fermentative bacteria. Geochemical characterization and modeling of the simulant and fluid chemistries identified clear differences between the biotic and abiotic experiments. These differences included the elimination of sulfur owing to the presence of sulfate-reducing bacteria and more general changes in pH associated with actively respiring cells that impacted the mineral assemblages formed. This study confirmed that a system simulating the fluid chemistry of Gale Crater could support a microbial community and that variation in chemistries under biotic and abiotic conditions can be used to inform future life-detection missions.

Given increasing rates of daily cannabis use and Cannabis Use Disorder (CUD) in the United States, it is imperative to understand CUD mechanisms in high-risk groups. Cannabis users with high distress intolerance (DI) are at elevated risk for severe and chronic CUD, but neural mechanisms linking CUD and DI are unknown. Cross-sectional data suggests that acute stress modulation of the cannabis and threat cue-elicited late positive potential (LPP), a neurophysiological marker of motivated attention, are possible mechanisms. However, longitudinal research is needed to clarify the roles of these elicited LPPs in CUD maintenance.Sixty cannabis users with high DI were randomized a brief computerized intervention targeting DI or a control intervention. Elicited LPPs were measured before and after a stressor at baseline and postintervention. Intervention effects on stress modulation of the cannabis and threat LPPs, as well as their prospective associations with CUD, were assessed.Elicited LPPs did not significantly change in either intervention group. Acute stress enhancement of the cannabis LPP predicted more severe CUD and greater chronicity at 4-month follow-up.Cannabis and threat LPPs were not altered by a brief DI intervention despite improvement in DI and cannabis use outcomes. Given that acute stress enhancement of the cannabis LPP predicted poorer CUD outcome, it may be a fruitful intervention target in distress intolerant cannabis users. (PsycInfo Database Record (c) 2022 APA, all rights reserved).