8 research outputs found

    Bryozoans are Major Modern Builders of South Atlantic Oddly Shaped Reefs

    Get PDF
    Supplementary information accompanies this paper at https://doi.org/10.1038/s41598-018-27961-6.In major modern reef regions, either in the Indo-Pacific or the Caribbean, scleractinian corals are described as the main reef framework builders, often associated with crustose coralline algae. We used underwater cores to investigate Late Holocene reef growth and characterise the main framework builders in the Abrolhos Shelf, the largest and richest modern tropical reef complex in the South Western Atlantic, a scientifically underexplored reef province. Rather than a typical coralgal reef, our results show a complex framework building system dominated by bryozoans. Bryozoans were major components in all cores and age intervals (2,000 yrs BP), accounting for up to 44% of the reef framework, while crustose coralline algae and coral accounted for less than 28 and 23%, respectively. Reef accretion rates varied from 2.7 to 0.9 mm yr−1, which are similar to typical coralgal reefs. Bryozoan functional groups encompassed 20 taxa and Celleporaria atlantica (Busk, 1884) dominated the framework at all cores. While the prevalent mesotrophic conditions may have driven suspensionfeeders’ dominance over photoautotrophs and mixotrophs, we propose that a combination of historical factors with the low storm-disturbance regime of the tropical South Atlantic also contributed to the region’s low diversity, and underlies the unique mushroom shape of the Abrolhos pinnacles.We thank CNPq/FAPES-Sisbiota/PELD, CAPES/IODP, CAPES/Ciências do Mar, and ANP/Brasoil for long term project funding. We also thank ICMBio for research permits and field logistic support, and Conservation International for providing and authorizing the use of the IKONOS image. JMW and JCB are International Visiting Researcher at UFES and JBRJ, supported by the Science Without Borders program. Zá Cajueiro provided invaluable field support and Ronaldo Francini, Carlos Janovitch and Lucio Engler helped in the drilling operations. This is a contribution from the Rede Abrolhos (abrolhos.org)

    Event-related potential studies of post-traumatic stress disorder: a critical review and synthesis

    Get PDF
    Despite the sparseness of the currently available data, there is accumulating evidence of information processing impairment in post-traumatic stress disorder (PTSD). Studies of event-related potentials (ERPs) are the main tool in real time examination of information processing. In this paper, we sought to critically review the ERP evidence of information processing abnormalities in patients with PTSD. We also examined the evidence supporting the existence of a relationship between ERP abnormalities and symptom profiles or severity in PTSD patients. An extensive Medline search was performed. Keywords included PTSD or post-traumatic stress disorder, electrophysiology or EEG, electrophysiology, P50, P100, N100, P2, P200, P3, P300, sensory gating, CNV (contingent negative variation) and MMN (mismatch negativity). We limited the review to ERP adult human studies with control groups which were reported in the English language. After applying our inclusion-exclusion review criteria, 36 studies were included. Subjects exposed to wide ranges of military and civilian traumas were studied in these reports. Presented stimuli were both auditory and visual. The most widely studied components included P300, P50 gating, N100 and P200. Most of the studies reported increased P300 response to trauma-related stimuli in PTSD patients. A smaller group of studies reported dampening of responses or no change in responses to trauma-related and/or unrelated stimuli. P50 studies were strongly suggestive of impaired gating in patients with PTSD. In conclusion, the majority of reports support evidence of information processing abnormalities in patients with PTSD diagnosis. The predominance of evidence suggests presence of mid-latency and late ERP components differences in PTSD patients in comparison to healthy controls. Heterogeneity of assessment methods used contributes to difficulties in reaching firm conclusions regarding the nature of these differences. We suggest that future ERP-PTSD studies utilize standardized assessment scales that provide detailed information regarding the symptom clusters and the degree of symptom severity. This would allow assessment of electrophysiological indices-clinical symptoms relationships. Based on the available data, we suggest that ERP abnormalities in PTSD are possibly affected by the level of illness severity. If supported by future research, ERP studies may be used for both initial assessment and treatment follow-up

    EEG Microstate Analysis in Drug-Naive Patients with Panic Disorder

    Get PDF
    Patients with panic disorder (PD) have a bias to respond to normal stimuli in a fearful way. This may be due to the preactivation of fear-associated networks prior to stimulus perception. Based on EEG, we investigated the difference between patients with PD and normal controls in resting state activity using features of transiently stable brain states (microstates). EEGs from 18 drug-naive patients and 18 healthy controls were analyzed. Microstate analysis showed that one class of microstates (with a right-anterior to left-posterior orientation of the mapped field) displayed longer durations and covered more of the total time in the patients than controls. Another microstate class (with a symmetric, anterior-posterior orientation) was observed less frequently in the patients compared to controls. The observation that selected microstate classes differ between patients with PD and controls suggests that specific brain functions are altered already during resting condition. The altered resting state may be the starting point of the observed dysfunctional processing of phobic stimuli

    From mRNP trafficking to spine dysmorphogenesis: The roots of fragile X syndrome

    No full text
    The mental retardation protein FMRP is involved in the transport of mRNAs and their translation at synapses. Patients with fragile X syndrome, in whom FMRP is absent or mutated, show deficits in learning and memory that might reflect impairments in the translational regulation of a subset of neuronal mRNAs. The study of FMRP provides important insights into the regulation and functions of local protein synthesis in the neuronal periphery, and increases our understanding of how these functions can produce specific effects at individual synapses

    From mRNP trafficking to spine dysmorphogenesis: the roots of fragile X syndrome

    No full text
    corecore