Rapid ecosystem-scale consequences of acute deoxygenation on a Caribbean coral reef

© The Author(s), 2021. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Johnson, M. D., Scott, J. J., Leray, M., Lucey, N., Bravo, L. M. R., Wied, W. L., & Altieri, A. H. Rapid ecosystem-scale consequences of acute deoxygenation on a Caribbean coral reef. Nature Communications, 12(1), (2021): 4522, https://doi.org/10.1038/s41467-021-24777-3.Loss of oxygen in the global ocean is accelerating due to climate change and eutrophication, but how acute deoxygenation events affect tropical marine ecosystems remains poorly understood. Here we integrate analyses of coral reef benthic communities with microbial community sequencing to show how a deoxygenation event rapidly altered benthic community composition and microbial assemblages in a shallow tropical reef ecosystem. Conditions associated with the event precipitated coral bleaching and mass mortality, causing a 50% loss of live coral and a shift in the benthic community that persisted a year later. Conversely, the unique taxonomic and functional profile of hypoxia-associated microbes rapidly reverted to a normoxic assemblage one month after the event. The decoupling of ecological trajectories among these major functional groups following an acute event emphasizes the need to incorporate deoxygenation as an emerging stressor into coral reef research and management plans to combat escalating threats to reef persistence.M.D.J. was funded by postdoctoral fellow awards from the Smithsonian Institution’s Marine Global Earth Observatory (MarineGEO) and the Smithsonian Tropical Research Institute (STRI); M.L. and N.L. were funded by postdoctoral support from the STRI Office of Fellowships. J.J.S. was funded by a grant from the Gordon and Betty Moore Foundation awarded to STRI and UC Davis (doi:10.37807/GBMF5603). L.M.R.B., W.L.W., and A.H.A. were supported by MarineGEO, a private funder, and STRI funds to A.H.A. Many of the computations were conducted on the Smithsonian High-Performance Cluster (SI/HPC), Smithsonian Institution (doi:10.25572/SIHPC). We thank Rachel Collin for facilities support at the Bocas del Toro Research Station, Plinio Gondola and the research station staff for logistical support, Roman Barco for insight into the functional analyses, Sherly Castro for informative feedback, and Mike Fox for assistance with community analyses. Research permits were provided by the Autoridad Nacional del Ambiente de Panamá. This paper is the result of research funded by the National Oceanic and Atmospheric Administration’s National Centers for Coastal Ocean Science Competitive Research Program under award NA18NOS4780170 to A.H.A. and M.D.J. through the University of Florida. This is contribution 257 from the Coastal Hypoxia Research Program and 86 from the Smithsonian’s MarineGEO and Tennenbaum Marine Observatories Network

A new online-test for changes in correlations between assets

Abstract We apply a new test to determine whether correlations between assets are constant over time. The test statistic is a suitably standardized maximum of cumulative empirical correlation coefficients. An empirical application to various assets suggests that the test performs well in applications. We also propose a portfolio strategy based on our test which hedges against potential financial crises and show that it works in practice

Verbal, Facial and Autonomic Responses to Empathy-Eliciting Film Clips by Disruptive Male Adolescents with High Versus Low Callous-Unemotional Traits

This study examined empathy-related responding in male adolescents with disruptive behavior disorder (DBD), high or low on callous-unemotional (CU) traits. Facial electromyographic (EMG) and heart rate (HR) responses were monitored during exposure to empathy-inducing film clips portraying sadness, anger or happiness. Self-reports were assessed afterward. In agreement with expectations, DBD adolescents with high CU traits showed significantly lower levels of empathic sadness than healthy controls across all response systems. Between DBD subgroups significant differences emerged at the level of autonomic (not verbal or facial) reactions to sadness, with high CU respondents showing less HR change from baseline than low CU respondents. The study also examined basal patterns of autonomic function. Resting HR was not different between groups, but resting respiratory sinus arrhythmia (RSA) was significantly lower in DBD adolescents with high CU traits compared to controls. Results support the notion that CU traits designate a distinct subgroup of DBD individuals

A meta-analysis of GFR slope as a surrogate endpoint for kidney failure

Glomerular filtration rate (GFR) decline is causally associated with kidney failure and is a candidate surrogate endpoint for clinical trials of chronic kidney disease (CKD) progression. Analyses across a diverse spectrum of interventions and populations is required for acceptance of GFR decline as an endpoint. In an analysis of individual participant data, for each of 66 studies (total of 186,312 participants), we estimated treatment effects on the total GFR slope, computed from baseline to 3 years, and chronic slope, starting at 3 months after randomization, and on the clinical endpoint (doubling of serum creatinine, GFR < 15 ml min−1 per 1.73 m2 or kidney failure with replacement therapy). We used a Bayesian mixed-effects meta-regression model to relate treatment effects on GFR slope with those on the clinical endpoint across all studies and by disease groups (diabetes, glomerular diseases, CKD or cardiovascular diseases). Treatment effects on the clinical endpoint were strongly associated with treatment effects on total slope (median coefficient of determination (R2) = 0.97 (95% Bayesian credible interval (BCI) 0.82–1.00)) and moderately associated with those on chronic slope (R2 = 0.55 (95% BCI 0.25–0.77)). There was no evidence of heterogeneity across disease. Our results support the use of total slope as a primary endpoint for clinical trials of CKD progression

Enhanced peripheral toll-like receptor responses in psychosis: further evidence of a pro-inflammatory phenotype

Low-grade peripheral inflammation is often present in psychotic patients. Toll-like receptors (TLRs) are pattern-recognition molecules that initiate inflammation. Our objective was to investigate the peripheral TLR activity in psychosis. Forty schizophrenia patients, twenty bipolar patients and forty healthy controls (HC) were recruited. Donated whole blood was cultured with TLR agonists for 24 h. Cell supernatants were analysed using a multiplex enzyme-linked immunosorbent assay approach to measure IL-1β, IL-6, IL-8 and tumour necrosis factor-α (TNFα). Plasma was analysed for cytokines, cortisol and acute phase proteins. Here, we show that selective TLR agonist-induced cytokine (IL-1β, IL-6, IL-8 and TNFα) release is enhanced in stimulated whole blood from schizophrenia and bipolar patients compared with HC. An exaggerated release of IL-1β, IL-6 and TNFα following treatment with the TLR2 agonist HKLM was detected in both disorders compared with controls. Enhanced TLR4-induced increases in IL-1β for both disorders coupled with TNFα increases for bipolar patients were observed. TLR8-induced increases in IL-1β for both disorders as well as IL-6 and TNFα increases for bipolar patients were detected. TLR9-induced increases in IL-8 for schizophrenia patients were also observed. No differences in TLR1, TLR3, TLR5, TLR6 or TLR7 activity were detected. Plasma levels of IL-6 were significantly elevated in bipolar patients while TNFα levels were significantly elevated in schizophrenia patients compared with controls. Plasma acute phase proteins were significantly elevated in bipolar patients. These data demonstrate that specific alterations in TLR agonist-mediated cytokine release contribute to the evidence of immune dysfunction in psychotic disorders

Somatostatin Receptor 1 and 5 Double Knockout Mice Mimic Neurochemical Changes of Huntington's Disease Transgenic Mice

Selective degeneration of medium spiny neurons and preservation of medium sized aspiny interneurons in striatum has been implicated in excitotoxicity and pathophysiology of Huntington's disease (HD). However, the molecular mechanism for the selective sparing of medium sized aspiny neurons and vulnerability of projection neurons is still elusive. The pathological characteristic of HD is an extensive reduction of the striatal mass, affecting caudate putamen. Somatostatin (SST) positive neurons are selectively spared in HD and Quinolinic acid/N-methyl-D-aspartic acid induced excitotoxicity, mimic the model of HD. SST plays neuroprotective role in excitotoxicity and the biological effects of SST are mediated by five somatostatin receptor subtypes (SSTR1-5). and R6/2 mice. Conversely, the expression of somatostatin receptor subtypes, enkephalin and phosphatidylinositol 3-kinases were strain specific. SSTR1/5 appears to be important in regulating NMDARs, DARPP-32 and signaling molecules in similar fashion as seen in HD transgenic mice.This is the first comprehensive description of disease related changes upon ablation of G- protein coupled receptor gene. Our results indicate that SST and SSTRs might play an important role in regulation of neurodegeneration and targeting this pathway can provide a novel insight in understanding the pathophysiology of Huntington's disease

The development of spontaneous facial responses to others’ emotions in infancy. An EMG study

Viewing facial expressions often evokes facial responses in the observer. These spontaneous facial reactions (SFRs) are believed to play an important role for social interactions. However, their developmental trajectory and the underlying neurocognitive mechanisms are still little understood. In the current study, 4- and 7-month old infants were presented with facial expressions of happiness, anger, and fear. Electromyography (EMG) was used to measure activation in muscles relevant for forming these expressions: zygomaticus major (smiling), corrugator supercilii (frowning), and frontalis (forehead raising). The results indicated no selective activation of the facial muscles for the expressions in 4-month-old infants. For 7-month-old infants, evidence for selective facial reactions was found especially for happy faces (leading to increased zygomaticus major activation) and fearful faces (leading to increased frontalis activation), while angry faces did not show a clear differential response. This suggests that emotional SFRs may be the result of complex neurocognitive mechanisms which lead to partial mimicry but are also likely to be influenced by evaluative processes. Such mechanisms seem to undergo important developments at least until the second half of the first year of life