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Subanesthetic ketamine infusion therapy can produce fast-acting antidepressant effects in patients with major depression. How single and repeated ketamine treatment modulates the whole-brain functional connectome to affect clinical outcomes remains uncharacterized.
Data-driven whole brain functional connectivity (FC) analysis was used to identify the functional connections modified by ketamine treatment in patients with major depressive disorder (MDD). MDD patients (N = 61, mean age = 38, 19 women) completed baseline resting-state (RS) functional magnetic resonance imaging and depression symptom scales. Of these patients, n = 48 and n = 51, completed the same assessments 24 h after receiving one and four 0.5 mg/kg intravenous ketamine infusions. Healthy controls (HC) (n = 40, 24 women) completed baseline assessments with no intervention. Analysis of RS FC addressed effects of diagnosis, time, and remitter status.
Significant differences (p < 0.05, corrected) in RS FC were observed between HC and MDD at baseline in the somatomotor network and between association and default mode networks. These disruptions in FC in MDD patients trended toward control patterns with ketamine treatment. Furthermore, following serial ketamine infusions, significant decreases in FC were observed between the cerebellum and salience network (SN) (p < 0.05, corrected). Patient remitters showed increased FC between the cerebellum and the striatum prior to treatment that decreased following treatment, whereas non-remitters showed the opposite pattern.
Results support that ketamine treatment leads to neurofunctional plasticity between distinct neural networks that are shown as disrupted in MDD patients. Cortico-striatal-cerebellar loops that encompass the SN could be a potential biomarker for ketamine treatment.
Healthcare employees were tested for antibodies against severe acute respiratory coronavirus virus 2 (SARS-CoV-2). Among 734 employees, the prevalence of SARS-CoV-2 antibodies was 1.6%. Employees with heavy coronavirus disease 2019 (COVID-19) exposure had similar antibody prevalence as those with limited or no exposure. Guidelines for PPE use seem effective for preventing COVID-19 infection in healthcare workers.
The Brechin Lagerstätte of southern Ontario contains an exceptionally diverse and well-preserved Late Ordovician (Katian) crinoid fauna. We describe four genera and eight species of camerate crinoids from the Brechin Lagerstätte, including six new species. Consequently, the total diversity of the fauna now stands at 27 genera and 39 nominal species, thereby making it the most taxonomically diverse Ordovician crinoid fauna known. Taxa described include the diplobathrid Pararchaeocrinus kiddi new species and the monobathrids Glyptocrinus ramulosus Billings, 1856, Periglyptocrinus priscus (Billings, 1857a), Periglyptocrinus astricus new species, Periglyptocrinus kevinbretti new species, Periglyptocrinus mcdonaldi new species, Periglyptocrinus silvosus new species, and Abludoglyptocrinus steinheimerae new species. We summarize the taxonomic composition, diversity, and abundance distribution of all known crinoids from the Brechin Lagerstätte to better characterize the paleoecological structure and complexity of the community. We establish that the fauna is dominated by the subclass Pentacrinoidea, both in terms of abundance and species richness. In addition, we analyze species-level abundance data using Relative Abundance Distribution (RAD) models to evaluate the ecological complexity of the paleocommunity. We found that community structure of the Brechin Lagerstätte is best explained by an ecologically ‘complex’ RAD model, which suggests that species partitioned niches along multiple resource axes and/or the presence of multiple ecological ways of life. These results indicate that the Brechin Lagerstätte is significant not only for being the most taxonomically diverse Katian crinoid assemblage, but also for being an early ecologically complex fauna that developed in the wake of the Great Ordovician Biodiversification Event.
We report the results of a survey of the fishes of Kāne‘ohe Bay, O‘ahu, conducted in 2017 as part of the Smithsonian Institution MarineGEO Hawaii bioassessment. We recorded 109 species in 43 families. The most speciose families were Acanthuridae (11 species), Gobiidae (11 species), Pomacentridae (10) and Chaetodontidae (9 species). Nine of the species that we collected are known or suspected to be introduced to the Hawaiian Islands. Specimens were identified, measured and photographed. All specimen vouchers were fixed in formalin and ultimately transferred to 75% ethanol for long-term storage. For nearly all species, we took multiple tissue samples from specimen vouchers prior to formalin-fixation; we preserved tissues in 95% ethanol and then stored them at −80°C. The 5′-end of the mitochondrial cytochrome oxidase I gene (mtCOI) was sequenced for 94 species to confirm their taxonomic identification. Using these barcode sequences, we also measured genetic distances between collected individuals and their conspecifics from other localities outside Hawaii to verify the hypothesis that Hawaiian populations of species broadly distributed throughout the Indo-Pacific may be genetically distinct. We present select case studies to demonstrate the potential for undiscovered endemism in the Hawaiian fish biota.
Schizophrenia is an aetiologically complex disorder associated with significant familial risk. It is marked also by reductions in whole brain, grey and possibly white matter volumes. How these pathological abnormalities are influenced by schizophrenia's genetic and environmental risk remains uncertain.
We investigated the relationship between familial and environmental risk on brain volume in twin pairs varying in their zygosity and concordance for schizophrenia, and healthy control twins, using a variety of complementary imaging strategies. These included region of interest and automated tissue segmentation volumes and voxel based morphometry.
We found that whole brain, grey, white, frontal and right hippocampal volumes were smaller in probands with schizophrenia compared to healthy controls. Well co-twins from MZ discordant pairs showed a trend towards lower white matter volume compared to the healthy controls. Well co-twins from DZ discordant pairs had smaller hippocampal volumes compared to the healthy controls. The patients with schizophrenia and their well co-twins from MZ discordant pairs differed in the superior frontal cortex using both region of interest and VBM techniques. Lower birth weight and hypoxia were both associated with lower whole brain volumes, and with lower white and grey matter volumes respectively.
Our data suggest that total brain and grey matter volume reductions in schizophrenia, possibly focused in part in the frontal cortex, are related primarily to unique environmental factors, including perinatal complications. The white matter and local hippocampal volume reductions suggest an additional vulnerability to genetic risk effects.
The social-environment has a critical impact on health. The proposed progress is by stimulation of downstream pathways, from the central nervous system to the periphery, which subsequently alters the cells’ gene expression and transcription, particularly affecting the immune system. Stressors such as childhood adversity and mental health problems have both separately, and together, been identified as having crucial impact on inflammatory and immune genes. We intend to investigate how depression alone, and depression in combination with childhood adversity, as markers of adverse life events, alter the immune system towards dysregulation and increases the risk of developing immune-related pathologies such as autoimmune, cardiovascular and neurodegenerative diseases. We hypothesize that depression has negative modulating effect on the immune system and thus increases the risk of autoimmune disease, severe infection and cancer. Childhood adversity sensitizes the immune system (i.e. forms a pipeline) to develop pathological dysregulations when subsequently exposed to stressors later in life. Furthermore, we predict a dose-response relationship between the gravity and number of stressors and the risk of dysregulation. This study links two nationwide population-based registers namely the Danish Psychiatric Central Register and the National Hospital Register to create a longitudinal cohort study. Rate ratios, and accompanying 95% confidence intervals will be obtained. Accordingly, this work yields additional knowledge to how the social-environment, specifically adverse life events, affects the risk of immune-related diseases. Thus this can improve understandings on the interplay of mental disorders and immune-related diseases, and subsequently establish fundament for future research and possibilities for treatment and prevention.
The Coronavirus (Covid-19) pandemic is exerting unprecedented pressure on NHS Health and Social Care provisions, with frontline staff, such as those of critical care units, encountering vast practical and emotional challenges on a daily basis. Although staff are being supported through organisational provisions, facilitated by those in leadership roles, the emergence of mental health difficulties or the exacerbation of existing ones amongst these members of staff is a cause for concern. Acknowledging this, academics and healthcare professionals alike are calling for psychological support for frontline staff, which not only addresses distress during the initial phases of the outbreak but also over the months, if not years, that follow. Fortunately, mental health services and psychology professional bodies across the United Kingdom have issued guidance to meet these needs. An attempt has been made to translate these sets of guidance into clinical provisions via the recently established Homerton Covid Psychological Support (HCPS) pathway delivered by Talk Changes (Hackney & City IAPT). This article describes the phased, stepped-care and evidence-based approach that has been adopted by the service to support local frontline NHS staff. We wish to share our service design and pathway of care with other Improving Access to Psychological Therapies (IAPT) services who may also seek to support hospital frontline staff within their associated NHS Trusts and in doing so, lay the foundations of a coordinated response.
Key learning aims
(1) To understand the ways staff can be psychologically and emotionally impacted by working on the frontline of disease outbreaks.
(2) To understand the ways in which IAPT services have previously supported populations exposed to crises.
(3) To learn ways of delivering psychological support and interventions during a pandemic context based on existing guidance and research.
Upper Ordovician (Katian) strata of the Lake Simcoe region of Ontario record a spectacularly diverse and abundant echinoderm fauna known as the Brechin Lagerstätte. Despite recognition as the most taxonomically diverse Katian crinoid paleocommunity, the Brechin Lagerstätte has received relatively little taxonomic study since Frank Springer published his classic monograph on the “Kirkfield fauna” in 1911.
Using a new collection of exceptionally preserved material, we evaluate all dicyclic inadunate crinoids occurring in the Brechin Lagerstätte, which is predominantly comprised of cladids (Eucladida and Flexibilia). We document 15 species across 11 genera, including descriptions of two new genera and four new species. New taxa include Konieckicrinus brechinensis n. gen. n. sp., K. josephi n. gen. n. sp., Simcoecrinus mahalaki n. gen. n. sp., and Dendrocrinus simcoensis n. sp.
Although cladids are not commonly considered major components of the Early Paleozoic Crinoid Macroevolutionary Fauna, which is traditionally conceived as dominated by disparids and diplobathrid camerates, they are the most diverse major lineage of crinoids occurring in the Brechin Lagerstätte. This unexpected result highlights the important roles of specimen-based taxonomy and systematic revisions in the study of large-scale diversity patterns.
Identifying correlates of extinction risk is important for understanding the underlying mechanisms driving differential rates of extinction and variability in the temporal durations of taxa. Increasingly, it is recognized that the effects of multiple, potentially interacting variables and phylogenetic relationships should be incorporated when studying extinction selectivity to account for covariation of traits and shared evolutionary history. Here, I explore a variety of biological and ecological controls on genus longevity in the global fossil record of diplobathrid crinoids by analyzing the combined effects of species richness, habitat preference, body size, filtration fan density, and food size selectivity. I employ a suite of taxic and phylogenetic approaches to (1) quantitatively compare and rank the relative effects of multiple factors on taxonomic longevity and (2) determine how phylogenetic comparative approaches alter interpretations of extinction selectivity.
I find controls on diplobathrid genus duration are hierarchically structured, where species richness is the primary predictor of duration, habitat is the secondary predictor, and combinations of ecological and biological traits are tertiary controls. Ecology plays an important but complex role in the generation of crinoid macroevolutionary patterns. Notably, tolerance of environmental heterogeneity promotes increased genus duration across diplobathrid crinoids, and the effects of traits related to feeding ecology vary depending on habitat lithology. Finally, I find accounting for phylogeny does not consistently decrease the significance of correlations between traits and genus duration, as is commonly expected. Instead, the strength of relationships between traits and duration may increase, decrease, or remain statistically similar, and both the magnitude and direction of these shifts are generally unpredictable. However, traits with strong correlations and/or moderately large effect sizes (Cohen's f2 > 0.15) under taxic approaches tend to remain qualitatively unchanged under phylogenetic approaches.
The philosophy of Gilles Deleuze has become popular in recent moves to embed approaches such as the new materialist and the posthuman in environmental education. Certainly, a newfound respect for the material universe, including the comprehension of the human place in it, and the tendency to a posthuman theoretical position, are both important given the contemporary environmental crisis, named as the Anthropocene. However, this article will argue that both these philosophies do not go far enough. This is because they must retain a political, social and critical edge if they are to be effective, and this edge can be too easily disregarded in the pursuit of increased engagement with the material and everything not human. In contrast, this article will put forward a Deleuzian approach to environmental education, based on the intellectual quadrant of Spinoza-Marx-Nietzsche-Bergson (Figure 1). It will be argued that only by fully connecting these often conflicting and disparate philosophies that a workable new synthesis for environmental education and a cartography for learning can be achieved. The Deleuzian approach to environmental education will be exemplified through an analysis of current environmental practises in schools as assemblage.
Mars is the fourth planet from the Sun and the outermost of the rocky, terrestrial planets that make up the inner solar system. Mars is the second smallest planet; only Mercury is smaller. Surface gravity on Mars is 3.71 m s–2, which is 37.6% that of the Earth. The present atmospheric pressure is low (~0.6 kPa) relative to Earth’s (101 kPa), and the atmosphere is mostly carbon dioxide (95%). The obliquity of Mars (tilt of the axis of rotation relative to the plane of orbit) is presently 25 degrees and may have varied by tens of degrees over the past tens of millions of years and longer (Laskar et al., 2004).
The rugged highland terrains of Noachis Terra and Terra Sabaea dominate the region. The higher-standing, tectonically deformed, and densely cratered Terra Sabaea contains Scylla and Charybdis Scopuli. Also present are Denning, Bouguer, Lambert, Dawes, Pollack, Schiaparelli, Tuscaloosa, and Bakhuysen craters. To the west, the relatively subdued, but still rugged highland region of Noachis Terra has Newcomb, Wislicenus, and Mädler craters; and Marikh and a portion of Evros Valles. Numerous other moderately to highly degraded craters are scattered throughout the area. Valley networks ranging from tens of kilometers to thousands of kilometers in length dissect much of the topography. Wide grabens scar parts of Terra Sabaea. The region slopes from close to 3,000 m above datum in Terra Sabaea to as low at –1,500 m in the northwest. The northeast region is a portion of the zone that occurs between highland terrains to the south and transition terrain of Arabia Terra to the north (MC-12).
Eridania quadrangle is composed almost entirely of the ancient cratered highland terrain of Terra Cimmeria, at 0–2 km elevation. The largest crater, Kepler, is about 230 km in diameter. Less-cratered, relatively low-lying plains are scattered throughout the quadrangle, including Eridania Planitia in the northwest corner and Planum Chronium in the southwest part of the quadrangle. Ridge systems occur throughout the quadrangle, with northeast-trending Eridania Scopulus forming the most prominent ridge.