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© 2020 The Author(s). Background: The capacity of reef-building corals to tolerate (or adapt to) heat stress is a key factor determining their resilience to future climate change. Changes in coral microbiome composition (particularly for microalgal endosymbionts and bacteria) is a potential mechanism that may assist corals to thrive in warm waters. The northern Red Sea experiences extreme temperatures anomalies, yet corals in this area rarely bleach suggesting possible refugia to climate change. However, the coral microbiome composition, and how it relates to the capacity to thrive in warm waters in this region, is entirely unknown. Results: We investigated microbiomes for six coral species (Porites nodifera, Favia favus, Pocillopora damicornis, Seriatopora hystrix, Xenia umbellata, and Sarcophyton trocheliophorum) from five sites in the northern Red Sea spanning 4° of latitude and summer mean temperature ranges from 26.6 °C to 29.3 °C. A total of 19 distinct dinoflagellate endosymbionts were identified as belonging to three genera in the family Symbiodiniaceae (Symbiodinium, Cladocopium, and Durusdinium). Of these, 86% belonged to the genus Cladocopium, with notably five novel types (19%). The endosymbiont community showed a high degree of host-specificity despite the latitudinal gradient. In contrast, the diversity and composition of bacterial communities of the surface mucus layer (SML) - a compartment particularly sensitive to environmental change - varied significantly between sites, however for any given coral was species-specific. Conclusion: The conserved endosymbiotic community suggests high physiological plasticity to support holobiont productivity across the different latitudinal regimes. Further, the presence of five novel algal endosymbionts suggests selection of certain genotypes (or genetic adaptation) within the semi-isolated Red Sea. In contrast, the dynamic composition of bacteria associated with the SML across sites may contribute to holobiont fun

Hyperpolarization-activated cyclic nucleotide-gated (HCN) channels control neuronal excitability and their dysfunction has been linked to epileptogenesis but few individuals with neurological disorders related to variants altering HCN channels have been reported so far. In 2014, we described five individuals with epileptic encephalopathy due to de novo HCN1 variants. To delineate HCN1-related disorders and investigate genotype-phenotype correlations further, we assembled a cohort of 33 unpublished patients with novel pathogenic or likely pathogenic variants: 19 probands carrying 14 different de novo mutations and four families with dominantly inherited variants segregating with epilepsy in 14 individuals, but not penetrant in six additional individuals. Sporadic patients had epilepsy with median onset at age 7 months and in 36% the first seizure occurred during a febrile illness. Overall, considering familial and sporadic patients, the predominant phenotypes were mild, including genetic generalized epilepsies and genetic epilepsy with febrile seizures plus (GEFS+) spectrum. About 20% manifested neonatal/infantile onset otherwise unclassified epileptic encephalopathy. The study also included eight patients with variants of unknown significance: One adopted patient had two HCN1 variants, four probands had intellectual disability without seizures, and three individuals had missense variants inherited from an asymptomatic parent. Of the 18 novel pathogenic missense variants identified, 12 were associated with severe phenotypes and clustered within or close to transmembrane domains, while variants segregating with milder phenotypes were located outside transmembrane domains, in the intracellular N- and C-terminal parts of the channel. Five recurrent variants were associated with similar phenotypes. Using whole-cell patch-clamp, we showed that the impact of 12 selected variants ranged from complete loss-of-function to significant shifts in activation kinetics and/or volta

This investigation studied the effects of transcranial direct current stimulation (tDCS) on the Attention Network Task (ANT) - a combination speeded response/flanker task, which elucidates activity of three attentional networks - alerting, orienting, and executive functioning. Anodal tDCS was applied over the right inferior frontal cortex at 0.1 mA or 2.0 mA for 30 minutes. Participants were tested prior to stimulation, roughly 30 minutes following cessation of stimulation, 70 minutes following cessation of stimulation, and 115 minutes following cessation of stimulation. Due to the areas being stimulated (RIFC), and results from previous studies that link the alerting network to frontal and parietal activation (Coull et al., 2001), and executive control function to the ACC and the lateral prefrontal cortex (Bush et al., 2000), it seemed reasonable that higher scores for these networks will be achieved by those in the active stimulation groups. However, the only network difference observed involved the alerting network, in an unexpected direction (higher scores for the sham group). The active group (2.0mA stimulation), while obtaining smaller differences in RT between conditions, responded faster across all conditions. These results, however, were rendered non-significant due to group differences observed at the baseline measure. It is possible the RT scores related to levels of concentration, though a third variable could be the root of observed differences. Thus, results are inconclusive given the current set of data.

Anthropogenically released CO2 is dissolving in the ocean, causing a decrease in bulk-seawater pH (ocean acidification). Projections indicate that the pH will drop 0.3 units from its present value by 2100 (ref. 1). However, it is unclear how the growth of plankton is likely to respond. Using simulations we demonstrate how pH and carbonate chemistry at the exterior surface of marine organisms deviates increasingly from those of the bulk sea water as organism metabolic activity and size increases. These deviations will increase in the future as the buffering capacity of sea water decreases with decreased pH and as metabolic activity increases with raised seawater temperatures. We show that many marine plankton will experience pH conditions completely outside their recent historical range. However, ocean acidification is likely to have differing impacts on plankton physiology as taxon-specific differences in organism size, metabolic activity and growth rates during blooms result in very different microenvironments around the organism. This is an important consideration for future studies in ocean acidification as the carbonate chemistry experienced by most planktonic organisms will probably be considerably different from that measured in bulk-seawater samples. An understanding of these deviations will assist interpretation of the impacts of ocean acidification on plankton of different size and metabolic activity. © 2012 Macmillan Publishers Limited. All rights reserved.

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The Ladies' repository: a monthly periodical, devoted to literature, arts, and religion. / Volume 24, Issue 2, Page(s) 75-76, (dlps) volume: acg2248.1-24.002, (dlps) article: acg2248.1-24.002:9, http://quod.lib.umich.edu/t/text/accesspolicy.html

The Ladies' repository: a monthly periodical, devoted to literature, arts, and religion. / Volume 24, Issue 2, Page(s) 81-87, (dlps) volume: acg2248.1-24.002, (dlps) article: acg2248.1-24.002:16, http://quod.lib.umich.edu/t/text/accesspolicy.html

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