Physical controls on the macrofaunal benthic biomass in Barrow Canyon, Chukchi Sea

Author Posting. © American Geophysical Union, 2021. This article is posted here by permission of American Geophysical Union for personal use, not for redistribution. The definitive version was published in Journal of Geophysical Research: Oceans 126(5), (2021): e2020JC017091, https://doi.org/10.1029/2020JC017091.A region of exceptionally high macrofaunal benthic biomass exists in Barrow Canyon, implying a carbon export process that is locally concentrated. Here we offer an explanation for this benthic “hotspot” using shipboard data together with a set of dynamical equations. Repeat occupations of the Distributed Biological Observatory transect in Barrow Canyon reveal that when the northward flow is strong and the density front in the canyon is sharp, plumes of fluorescence and oxygen extend from the pycnocline to the seafloor in the vicinity of the hotspot. By solving the quasi-geostrophic omega equation with an analytical flow field fashioned after the observations, we diagnose the vertical velocity in the canyon. This reveals that, as the along stream flow converges into the canyon, it drives a secondary circulation cell with strong downwelling on the cyclonic side of the northward flow. The downwelling quickly advects material from the pycnocline to the seafloor in a vertical plume analogous to those seen in the observations. The plume occurs only when the phytoplankton reside in the pycnocline, since the near-surface vertical velocity is weak, also consistent with the observations. Using a wind-based proxy to represent the strength of the northward flow and hence the pumping, in conjunction with a satellite-derived phytoplankton source function, we construct a time series of carbon supply to the bottom of Barrow Canyon.This work was funded by National Science Foundation grants PLR-1504333 and OPP-1733564 (Robert S. Pickart, Frank Bahr), OPP-1822334 (Michael A. Spall), PLR-1304563 (Kevin R. Arrigo), OPP-1204082 and OPP-1702456 (Jacqueline M. Grebmeier); National Oceanic and Atmospheric Administration grants NA14OAR4320158 and NA19OAR4320074 (Robert S. Pickart, Peigen Lin, Leah T. McRaven), CINAR-22309.02 (Jacqueline M. Grebmeier)

Evidence for massive and recurrent toxic blooms of Alexandrium catenella in the Alaskan Arctic

© The Author(s), 2021. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Anderson, D. M., Fachon, E., Pickart, R. S., Lin, P., Fischer, A. D., Richlen, M. L., Uva, V., Brosnahan, M. L., McRaven, L., Bahr, F., Lefebvre, K., Grebmeier, J. M., Danielson, S. L., Lyu, Y., & Fukai, Y. Evidence for massive and recurrent toxic blooms of Alexandrium catenella in the Alaskan Arctic. Proceedings of the National Academy of Sciences of the United States of America, 118(41) (2021): e2107387118, https://doi.org/10.1073/pnas.2107387118.Among the organisms that spread into and flourish in Arctic waters with rising temperatures and sea ice loss are toxic algae, a group of harmful algal bloom species that produce potent biotoxins. Alexandrium catenella, a cyst-forming dinoflagellate that causes paralytic shellfish poisoning worldwide, has been a significant threat to human health in southeastern Alaska for centuries. It is known to be transported into Arctic regions in waters transiting northward through the Bering Strait, yet there is little recognition of this organism as a human health concern north of the Strait. Here, we describe an exceptionally large A. catenella benthic cyst bed and hydrographic conditions across the Chukchi Sea that support germination and development of recurrent, locally originating and self-seeding blooms. Two prominent cyst accumulation zones result from deposition promoted by weak circulation. Cyst concentrations are among the highest reported globally for this species, and the cyst bed is at least 6× larger in area than any other. These extraordinary accumulations are attributed to repeated inputs from advected southern blooms and to localized cyst formation and deposition. Over the past two decades, warming has likely increased the magnitude of the germination flux twofold and advanced the timing of cell inoculation into the euphotic zone by 20 d. Conditions are also now favorable for bloom development in surface waters. The region is poised to support annually recurrent A. catenella blooms that are massive in scale, posing a significant and worrisome threat to public and ecosystem health in Alaskan Arctic communities where economies are subsistence based.Funding for D.M.A., R.S.P., E.F., P.L., A.D.F., V.U., M.L.B., L.M., F.B., and M.L.R. was provided by grants from the NSF Office of Polar Programs (Grants OPP-1823002 and OPP-1733564) and the National Ocanic and Atmospheric Administration (NOAA) Arctic Research program (through the Cooperative Institute for the North Atlantic Region [CINAR; Grants NA14OAR4320158 and NA19OAR4320074]), for J.M.G. through CINAR 22309.07 UMCES (University of Maryland Center for Environmental Science), and for D.M.A. and K.L. through NOAA’s Center for Coastal and Ocean Studies Ecology and Oceanography of Harmful Algal Blooms (ECOHAB) Program (NA20NOS4780195). Funding for D.M.A., M.L.R., M.L.B., E.F., V.U., and A.D.F. was also provided by NSF (Grant OCE-1840381) and NIH (Grant 1P01-ES028938-01) through the Woods Hole Center for Oceans and Human Health. S.L.D. was supported by North Pacific Research Board IERP Grants A91-99a and A91-00a. This is IERP publication ArcticIERP-41 and ECOHAB Contribution No. ECO983

Faking bad in workers compensation psychological assessments:Elevation rates of negative distortion scales on the personality assessment inventory in an Australian sample

The workers compensation system provides a clear external incentive for deliberate feigning of physical or mental illness to some individuals. Although it has been asserted that all pre-liability workers compensation psychological assessments should involve assessment of deliberate feigning, the lack of an agreed standard for assessing this response style creates a substantial challenge in practice. Over the last two decades, substantial attention has been given to measures of psychopathology that also include validated negative distortion indices. The Personality Assessment Inventory) has been validated in both the clinical and forensic population, and is reportedly used by many Australian psychologists. This study explores rates of elevation of negative distortion scales on the PAI as a potential indicator of deliberate feigning in a large Australian workers compensation sample

The last truth to determine but the first to consider: navigating negative response distortion on the PAI in a forensic context

Negative response distortion must be a consideration for any psychologist endeavouring to measure reported psychopathology in populations for whom there exists an external incentive for a diagnosis. The Personality Assessment Inventory (Morey, 1991) is increasingly being used in psychological assessment in the forensic arena. This paper presents an overview of the validation of the negative validity indices of the PAI to interpret data from a recent archival file review of 400 individuals who participated in assessment as part of a compensation claim process or in preparation for criminal sentencing. Whilst malingering must be a standard consideration in any forensic assessment, a systematic process for the determination of the veracity of client reports has not been developed. Practical application of the PAI validity indices to this detection process are discussed and specific recommendations are made

What we think affects how we behave: the relationship between beliefs and practice in psychologists\u27 detection of malingering

Malingering is the deliberate fabrication or gross exaggeration of symptoms in order to gain a specific outcome. Whilst the definition of this form of deception has remained relatively unchanged for over a century, the reasons that some individuals engage in malingering is less clear. Whilst several explanatory models of malingering were proposed by Rogers (1990) nearly 20 years ago, the relationship between psychologists’ beliefs about malingering and their assessment practice has yet to be explored. The current paper presents data from a recent Australian study, which explored differences in Australian psychologists’ beliefs about malingering and the influence of such beliefs on their assessment behaviour

Longitudinal Relations between Emotion Restraint Values, Life Stress, and Internalizing Symptoms among Vietnamese American and European American Adolescents

Objective: Recent research has documented cultural differences in the extent and manner in which various forms of emotion regulation are linked with psychological well-being. Most of these studies, however, have been cross-sectional, nor have they directly examined the values underlying the use of emotion regulation. The present study examined emotion restraint values and their interactions with life stress in predicting internalizing symptoms across time among Vietnamese American and European American adolescents. The study focused on adolescence as a critical developmental period during which life stress and internalizing symptoms increase significantly. Method: Vietnamese American (n = 372) and European American (n = 304) adolescents' levels of emotion restraint values, internalizing symptoms, and stress were assessed at two timepoints six months apart. Results: Results indicated differential associations between emotion restraint values, stress, and symptoms over time for the two groups. For Vietnamese American adolescents, emotion restraint values did not predict depressive, anxiety, or somatic symptoms. For European American adolescents, emotion restraint values predicted higher somatic symptoms but buffered against the effects of interpersonal stress on anxiety and depressive symptoms. Conclusions: These results provide increased understanding of the role of values related to emotion restraint in shaping adolescent internalizing symptoms and responses to stress across cultural groups. Implications of the findings for guiding intervention efforts are discussed