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Alongside the Chicxulub meteorite impact, Deccan volcanism is considered a primary trigger for the Cretaceous-Paleogene (K-Pg) mass extinction. Models suggest that volcanic outgassing of carbon and sulfur--potent environmental stressors--drove global temperature change, but the relative timing, duration, and magnitude of such change remains uncertain. Here, we use the organic paleothermometer MBT'5me and the carbon-isotope composition of two K-Pg-spanning lignites from the western Unites States, to test models of volcanogenic air temperature change in the ~100 kyr before the mass extinction. Our records show long-term warming of ~3°C, probably driven by Deccan CO2 emissions, and reveal a transient (<10 kyr) ~5°C cooling event, coinciding with the peak of the Poladpur "pulse" of Deccan eruption ~30 kyr before the K-Pg boundary. This cooling was likely caused by the aerosolization of volcanogenic sulfur. Temperatures returned to pre-event values before the mass extinction, suggesting that, from the terrestrial perspective, volcanogenic climate change was not the primary cause of K-Pg extinction. [ABSTRACT FROM AUTHOR]

Clinical psychologists are underrepresented in treatment provision for persons with serious mental illness (SMI). Training-based and individual-level (including stigma among psychologists) factors may contribute to the establishment and perpetuation of this underrepresentation. Very little research has examined how these factors may impact doctoral students' attitudes toward people with SMI. This study aimed to assess the current state of SMI training in clinical psychology and explore factors associated with mental health stigma among clinical doctoral students. Data were collected in two stages: (a) a national sample of directors of clinical trainings (n = 87) provided program-level data on SMI training and (b) students from select programs (n = 329) completed a survey on attitudes and associated factors. Analyses examined the relationship among four dimensions of student attitudes with individual, experiential, and training level factors. Overall, clinical training in SMI has shown little to no expansion over the last decade. Recovery knowledge, burnout, and disidentification emerged as the strongest and most consistent correlates of attitudes. Other associated factors included training in acute settings and the presence of SMI-focused faculty. Future research should examine the specific nature of SMI training and the role this may play in forming attitudes. Further, research must aim to establish specific recommendations for training reform and adapt clinician-based stigma interventions to student populations. [ABSTRACT FROM AUTHOR]

The Cretaceous-Paleogene (K-Pg) boundary marks one of the five major mass extinctions of the Phanerozoic. The ways in which the climate system responded to a bolide impact and extensive volcanism at this time over different time scales are highly debated. We used the distribution of branched tetraether lipids (brGDGT) from fossil peats at two sites in Saskatchewan, Canada (paleolatitude -55°N), to generate a high-resolution (millennial) record of mean annual air temperature (MAAT) spanning the last -4 k.y. of the Cretaceous and the first -30 k.y. of the Paleogene. Our study shows that MAATs ranged from 16 to 29 °C, with the highest value in the first millennia of the Paleogene. The earliest Paleogene averaged -25 °C--maintaining or enhancing warmth from the latest Cretaceous--followed by a general cooling to -20 °C over the following -30 k.y. No abrupt postboundary cooling (e.g., an "impact winter") or abrupt warming is evident in our data, implying that if such phenom- ena occurred, their duration was relatively short-lived (i.e., sub-millennial-scale). Further, no long-term impact- or volcanism-driven warming is evident. The range of temperature change observed is considerably greater than that derived from marine proxy records over the same time interval. Our findings therefore more properly place bounds on the magnitude and duration of temperature change on land during this critical interval--the main setting for the demise of nonavian dinosaurs and the rise of mammals. [ABSTRACT FROM AUTHOR]

The greenhouse world of the mid‐Cretaceous (~94 Ma) was punctuated by an episode of abrupt climatic upheaval: Oceanic Anoxic Event 2. High‐resolution climate records reveal considerable changes in temperature, carbon cycling, and ocean chemistry during this climatic perturbation. In particular, an interval of cooling has been detected in the English Chalk on the basis of an invasive boreal fauna and bulk oxygen‐isotope excursions registered during the early stages of Oceanic Anoxic Event 2—a phenomenon known as the Plenus Cold Event, which has tentatively been correlated with climatic shifts worldwide. Here we present new high‐resolution neodymium‐, carbon‐, and oxygen‐isotope data, as well as elemental chromium concentrations and cerium anomalies, from the English Chalk exposed at Dover, UK, which we evaluate in the context of >400 records from across the globe. A negative carbon‐isotope excursion that correlates with the original "Plenus Cold Event" is consistently expressed worldwide, and CO2 proxy records, where available, indicate a rise and subsequent fall in CO2 over the Plenus interval. However, variability in the timing and expression of cooling at different sites suggests that, although sea‐surface paleotemperatures may reflect a response to global CO2 change, local processes likely played a dominant role at many sites. Variability in the timing and expression of changes in water mass character, and problems in determining the driver of observed proxy changes, suggest that no single simple mechanism can link the carbon cycle to oceanography during the Plenus interval and other factors including upwelling and circulation patterns were locally important. As such, it is proposed that the Plenus carbon‐isotope event is a more reliable stratigraphic marker to identify the Plenus interval, rather than any climatic shifts that may have been overprinted by local effects. Key Points: This study is the first to review mechanistic interactions, and temporal leads and lags, between temperature, seawater chemistry, and CO2 within the Plenus intervalThe negative carbon‐isotope excursion during the Plenus interval was a global event driven by a CO2 increase, and appears decoupled from cooling and circulation changesCooling was not globally synchronous; local climatic and environmental responses to the CO2 change are more complex than previously understood [ABSTRACT FROM AUTHOR]

Background: A large proportion of clients served by Assertive Community Treatment (ACT) teams in New York City (NYC) are referred through "Assisted Outpatient Treatment" (AOT), which involves civil commitment to outpatient services. Research indicates that clients perceive AOT to be coercive, but it is unclear how this impacts the therapeutic relationships with ACT teams. We used mixed-methods to examine and compare perceptions of the therapeutic relationship and associated factors between ACT clients who were, and were not, referred through AOT. Method: Thirty persons receiving ACT services in NYC (15 AOT, 15 non-AOT) completed qualitative interviews about perceptions of treatment and referral, as well as measures of therapeutic alliance, procedural fairness, experienced coercion, shared decision-making, and self-stigma. Results: Quantitative findings revealed no differences in measures between AOT and non-AOT participants, with the exception being perception of "negative pressures" in the referral process, which was higher in the AOT group. However, qualitative findings were more mixed, with a notable subgroup of AOT-participants endorsing themes of paternalism and coercion in the referral and treatment decision-making process. Discussion: Findings indicate that the impact of AOT-referral on perceptions of ACT services is complex, and that AOT referrals impact treatment relationships in a subset of clients. [ABSTRACT FROM AUTHOR]

The Late Cretaceous was a greenhouse world, characterized by elevated temperatures and high atmospheric pCO2. Even in the context of an extreme greenhouse climate, existing planktic foraminiferal δ18O data from the Falkland Plateau (paleolatitude of ~55°S) suggest anomalous warmth, with sea‐surface temperatures (SSTs) >30 °C for much of the Late Cretaceous, followed by sudden cooling in the Campanian. Over the last two decades, there has been discussion as to whether these high δ18O‐based SSTs reflect a genuine temperature signal and, if so, whether there was a local temperature anomaly in the South Atlantic or whether the data are representative of zonal paleotemperatures at 55°S. To provide new insights into the degree of ocean warming in the southern high latitudes during the Late Cretaceous (Cenomanian to Campanian), new SST records from the Falkland and Kerguelen Plateaus are presented here using the organic geochemical paleothermometer TetraEther indeX of 86 carbon atoms (TEX86). Overall, the TEX86 data support the δ18O data, indicating extreme and widespread warmth in the middle to high southern latitudes in the Late Cretaceous, with SSTs from 27 to 37 °C. Crucially, the TEX86 data show slow, steady cooling from the Turonian to the Campanian and suggest that temperature gradients during the Campanian did not become as steep as suggested by some planktic foraminiferal data. Key Points: New TEX86 data show extreme warmth in the southern high latitudes during the Late CretaceousThese data indicate slow, steady cooling from the Turonian–mid–Campanian [ABSTRACT FROM AUTHOR]