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Re‐Os isotope‐dilution geochronology has been widely used to date the timing of molybdenite, pyrite and chalcopyrite formation across a variety of geological settings. However, in situ methods have been impeded by the isobaric interference of 187Re on 187Os. In situ Re‐Os geochronology using LA‐ICP‐MS/MS has been shown to be a useful technique to chemically separate Os from Re, as Os reacts with CH4 to create higher‐mass reaction products, which can then be measured with minimised interference of 187Re. However, application of the method requires matrix‐matched primary reference materials, e.g., age‐homogenous molybdenite amenable to laser ablation. Here, we characterise and present two new molybdenite mineral reference materials for in situ Re‐Os geochronology by LA‐ICP‐MS/MS, verified by ID‐TIMS Re‐Os measurements. We also present case studies from molybdenite samples with varying Re mass fractions and Re‐Os age mapping. The method provides accurate and precise age data, with excellent precision for high Re samples. The benefits of the LA‐ICP‐MS/MS approach include: (1) simple sample preparation, (2) rapid data acquisition, (3) targeting of specific textural domains including growth zones and (4) the ability to simultaneously collect trace elements used to link the timing and conditions of ore‐formation. [ABSTRACT FROM AUTHOR]

Introduction: Correctional workers (CWs) are frequently exposed to potentially traumatic events in the workplace, leading to an increased prevalence of mental health concerns. Online psychotherapy can address many of the barriers CWs face when seeking adequate mental health care. Despite their benefits, CWs' experience using digital mental health interventions is relatively unknown. This information could be valuable in developing enhanced care delivery to improve recruitment, retention, satisfaction, and treatment outcomes. Methods: This study investigated the experiences of a sample of CWs enrolled in a clinical trial evaluating the efficacy of the Online Psychotherapy Tool (OPTT) in this population. Participants were surveyed and interviewed to capture their opinions and feedback on the program. Survey analysis was conducted through Qualtrics statistical analysis software. The interview transcripts and open-ended survey questions were analyzed using thematic analysis methods in NVivo. Results: Participants (n=14) were cis-gender, predominantly white, with an average age of 38 years. While most respondents preferred in-person therapy, they also reported the benefits of the online psychotherapy program. Specifically, they expressed positive perceptions of the platform, the quality and interaction of their care provider, and the homework assignments and skills learned. Lack of motivation to complete weekly homework assignments was a frequently cited challenge. Unhelpful aspects of the therapy noted issues with the online format and frustration with certain program elements. Discussion: Participants expressed a positive outlook on the program, the platform, and treatment outcomes. A preference for in-person therapy was still indicated, demonstrating the need to focus on engagement in digital mental health interventions. In addition, the findings of this study shed light on the factors that can influence help-seeking in this population, including stigma in the work environment, demanding work schedules, workplace perceptions, and previous experiences accessing mental health services. [ABSTRACT FROM AUTHOR]

Copyright of Canadian Journal of Psychiatry is the property of Sage Publications Inc. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Introduction: An increased proclivity towards violence is often associated with those diagnosed with schizophrenia (SCZ), despite contradictory findings from prior studies exploring the association between violence and SCZ. Evidence has shown that certain comorbidities, specifically the presence of a substance use disorders, can result in increased aggression in those with SCZ. Copy number variation (CNV) load has also previously been implicated in the genetic vulnerability of individuals with SCZ. For this study, we aimed to determine whether CNV load correlates with increased violence in SCZ. Methods: Community-dwelling patients diagnosed with SCZ spectrum disorders (n = 203) were recruited from a non-forensic population. The assessment for aggression was completed using a cross-sectional and retrospective design, and CNV analysis was conducted analysing genomic DNA using the Illumina Omni 2.5 array. Results: No correlation between the number of CNV events (either deletion or duplication) and the severity of the physical violence episode index was found. However, there was a significant association between larger deletion events across the violent behaviours under investigation. Discussion: These results need to be confirmed in more extensive studies using standardized tools developed for non-forensic populations, such as the Brown-Goodwin Scale of Aggression. [ABSTRACT FROM AUTHOR]

Copyright of Canadian Journal of Psychiatry is the property of Sage Publications Inc. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

On the anoxic Archean Earth, prior to the onset of oxidative weathering, electron acceptors were relatively scarce, perhaps limiting microbial productivity. An important metabolite may have been sulfate produced during the photolysis of volcanogenic SO2 gas. Multiple sulfur isotope data can be used to track this sulfur source, and indeed this record indicates SO2 photolysis dating back to at least 3.7 Ga, that is, as far back as proposed evidence of life on Earth. However, measurements of multiple sulfur isotopes in some key strata from that time can be challenging due to low sulfur concentrations. Some studies have overcome this challenge with NanoSIMS or optimized gas‐source mass spectrometry techniques, but those instruments are not readily accessible. Here, we applied an aqua regia leaching protocol to extract small amounts of sulfur from whole rocks for analyses of multiple sulfur isotopes by multi‐collector inductively coupled plasma mass spectrometry (MC‐ICP‐MS). Measurements of standards and replicates demonstrate good precision and accuracy. We applied this technique to meta‐sedimentary rocks with putative biosignatures from the Eoarchean Isua Supracrustal Belt (ISB, >3.7 Ga) and found positive ∆33S (1.40–1.80‰) in four meta‐turbidites and negative ∆33S (−0.80‰ and −0.66‰) in two meta‐carbonates. Two meta‐basalts do not display significant mass‐independent fractionation (MIF, −0.01‰ and 0.16‰). In situ Re–Os dating on a molybdenite vein hosted in the meta‐turbidites identifies an early ca. 3.7 Ga hydrothermal phase, and in situ Rb–Sr dating of micas in the meta‐carbonates suggests metamorphism affected the rocks at ca. 2.2 and 1.7 Ga. We discuss alteration mechanisms and conclude that there is most likely a primary MIF‐bearing phase in these meta‐sediments. Our new method is therefore a useful addition to the geochemical toolbox, and it confirms that organisms at that time, if present, may indeed have been fed by volcanic nutrients. [ABSTRACT FROM AUTHOR]