Platinum group element signatures in the North Atlantic Igneous Province: Implications for mantle controls on metal budgets during continental breakup

The North Atlantic Igneous Province (NAIP) is a large igneous province (LIP) that includes a series of lava suites erupted from the earliest manifestations of the (proto)-Icelandic plume, through continental and ultimately oceanic rifting. The lavas of one of these sub-provinces, the British Palaeogene Igneous Province (BPIP), were some of the first lavas to be erupted in the NAIP and overlie a thick crustal basement and sedimentary succession with abundant S-rich mudrocks. We present the first platinum-group element (PGE) and Au analyses of BPIP flood basalts from the main lava fields of the Isle of Mull and Morvern and the Isle of Skye, in addition to a suite of shallow crustal dolerite volcanic plugs on Mull, and other minor lavas suites. BPIP lavas display both Ssaturated and S-undersaturated trends which, coupled with elevated PGE abundances (> MORB), suggest that the BPIP is one of the most prospective areas of the NAIP to host Ni-Cu-PGE-(Au) mineralisation in conduit systems. Platinum-group element, Au and chalcophile element abundances in lavas from West and East Greenland, and Iceland, are directly comparable to BPIP lavas, but the relative abundances of Pt and Pd vary systematically between lavas suites of different ages. The oldest lavas (BPIP and West Greenland) have a broadly chondritic Pt/Pd ratio (~ 1.9). Lavas from East Greenland have a lower Pt/Pd ratio (~ 0.8) and the youngest lavas from Iceland have the lowest Pt/Pd ratio of the NAIP (~ 0.4). Hence, Pt/Pd ratio of otherwise equivalent flood basalt lavas varies temporally across the NAIP and appears to be coincident with the changing geodynamic environment of the (proto)-Icelandic plume through time. We assess the possible causes for such systematic Pt/Pd variation in light of mantle plume and lithospheric controls, and suggest that this reflects a change in the availability of lithospheric mantle Pt-rich sulphides for entrainment in ascending plume magmas. Hence the precious metal systematics and potential prospectivity of a LIP may be affected by contamination of plume-derived magmas by subcontinental lithospheric mantle at the margins of cratons that has been enriched by Palaeoproterzoic orogenesis

Genome sequence of a gammaherpesvirus from a common bottlenose dolphin (Tursiops truncatus)

A herpesvirus genome was sequenced directly from a biopsy specimen of a rectal lesion from a female common bottlenose dolphin. This genome sequence comprises a unique region (161,235 bp) flanked by multiple copies of a terminal repeat (4,431 bp) and contains 72 putative genes. The virus was named common bottlenose dolphin gammaherpesvirus 1

An injectable bone marrow-like scaffold enhances T cell immunity after hematopoietic stem cell transplantation.

Allogeneic hematopoietic stem cell transplantation (HSCT) is a curative treatment for multiple disorders, but deficiency and dysregulation of T cells limit its utility. Here we report a biomaterial-based scaffold that mimics features of T cell lymphopoiesis in the bone marrow. The bone marrow cryogel (BMC) releases bone morphogenetic protein-2 to recruit stromal cells and presents the Notch ligand Delta-like ligand-4 to facilitate T cell lineage specification of mouse and human hematopoietic progenitor cells. BMCs subcutaneously injected in mice at the time of HSCT enhanced T cell progenitor seeding of the thymus, T cell neogenesis and diversification of the T cell receptor repertoire. Peripheral T cell reconstitution increased ~6-fold in mouse HSCT and ~2-fold in human xenogeneic HSCT. Furthermore, BMCs promoted donor CD4+ regulatory T cell generation and improved survival after allogeneic HSCT. In comparison to adoptive transfer of T cell progenitors, BMCs increased donor chimerism, T cell generation and antigen-specific T cell responses to vaccination. BMCs may provide an off-the-shelf approach for enhancing T cell regeneration and mitigating graft-versus-host disease in HSCT

Aortic valve stenotic area calculation from phase contrast cardiovascular magnetic resonance: the importance of short echo time

<p>Abstract</p> <p>Background</p> <p>Cardiovascular magnetic resonance (CMR) can potentially quantify aortic valve area (AVA) in aortic stenosis (AS) using a single-slice phase contrast (PC) acquisition at valve level: AVA = aortic flow/aortic velocity-time integral (VTI). However, CMR has been shown to underestimate aortic flow in turbulent high velocity jets, due to intra-voxel dephasing. This study investigated the effect of decreasing intra-voxel dephasing by reducing the echo time (TE) on AVA estimates in patients with AS.</p> <p>Method</p> <p>15 patients with moderate or severe AS, were studied with three different TEs (2.8 ms/2.0 ms/1.5 ms), in the main pulmonary artery (MPA), left ventricular outflow tract (LVOT) and 0 cm/1 cm/2.5 cm above the aortic valve (AoV). PC estimates of stroke volume (SV) were compared with CMR left ventricular SV measurements and PC peak velocity, VTI and AVA were compared with Doppler echocardiography. CMR estimates of AVA obtained by direct planimetry from cine acquisitions were also compared with the echoAVA.</p> <p>Results</p> <p>With a TE of 2.8 ms, the mean PC SV was similar to the ventricular SV at the MPA, LVOT and AoV_{0 cm}(by Bland-Altman analysis bias ± 1.96 SD, 1.3 ± 20.2 mL/-6.8 ± 21.9 mL/6.5 ± 50.7 mL respectively), but was significantly lower at AoV₁and AoV_2.5(-29.3 ± 31.2 mL/-21.1 ± 35.7 mL). PC peak velocity and VTI underestimated Doppler echo estimates by approximately 10% with only moderate agreement. Shortening the TE from 2.8 to 1.5 msec improved the agreement between ventricular SV and PC SV at AoV_{0 cm}(6.5 ± 50.7 mL vs 1.5 ± 37.9 mL respectively) but did not satisfactorily improve the PC SV estimate at AoV_{1 cm}and AoV_{2.5 cm}. Agreement of CMR AVA with echoAVA was improved at TE 1.5 ms (0.00 ± 0.39 cm²) versus TE 2.8 (0.11 ± 0.81 cm²). The CMR method which agreed best with echoAVA was direct planimetry (-0.03 cm²± 0.24 cm²).</p> <p>Conclusion</p> <p>Agreement of CMR AVA at the aortic valve level with echo AVA improves with a reduced TE of 1.5 ms. However, flow measurements in the aorta (AoV 1 and 2.5) are underestimated and 95% limits of agreement remain large. Further improvements or novel, more robust techniques are needed in the CMR PC technique in the assessment of AS severity in patients with moderate to severe aortic stenosis.</p

TEAMwork: Testing Emotional Attunement and Mutuality During Parent-Adolescent fMRI.

The parent-child relationship and family context influence the development of emotion regulation (ER) brain circuitry and related skills in children and adolescents. Although both parents' and children's ER neurocircuitry simultaneously affect how they interact with one another, neuroimaging studies of parent-child relationships typically include only one member of the dyad in brain imaging procedures. The current study examined brain activation related to parenting and ER in parent-adolescent dyads during concurrent fMRI scanning with a novel task - the Testing Emotional Attunement and Mutuality (TEAM) task. The TEAM task includes feedback trials indicating the other dyad member made an error, resulting in a monetary loss for both participants. Results indicate that positive parenting practices as reported by the adolescent were positively correlated with parents' hemodynamic activation of the ventromedial prefrontal cortex, a region related to empathy, during these error trials. Additionally, during feedback conditions both parents and adolescents exhibited fMRI activation in ER-related regions, including the dorsolateral prefrontal cortex, anterior insula, fusiform gyrus, thalamus, caudate, precuneus, and superior parietal lobule. Adolescents had higher left amygdala activation than parents during the feedback condition. These findings demonstrate the utility of dyadic fMRI scanning for investigating relational processes, particularly in the parent-child relationship

Oxygen isotopes and volatile contents of the Gorgona komatiites, Colombia: A confirmation of the deep mantle origin of H2O

We report O isotopes in olivine grains (Fo89–93) and volatile contents (CO2, H2O, F, S, Cl) in olivine-hosted melt inclusions from one Gorgona picrite and five komatiites with the aim of constraining the origin of H2O in these magmas. These samples have previously been analysed for major and trace elements and volatile concentrations (H2O, S, Cl) and B isotopes in melt inclusions. A distinctive feature of the included melts is relatively high contents of volatile components and boron, which show positive anomalies in, otherwise depleted, primitive mantle normalised trace and rare earth element patterns and range in δ11B from −11.5 to 15.6‰. In this study, the olivines were systematically analysed for O isotopes (1) in the centre of grains, (2) near the grain boundaries and, (3) as close as possible to the studied melt inclusions. The majority of olivines (∼66%) are “mantle”-like, ‰‰ 4.8‰≤δ18O≤5.5‰ , with a subordinate but still significant number (∼33%) above, and only 2 grains below, this range. There is no systematic difference between the central and marginal parts of the grains. Higher than “mantle” δ18OOl values are ascribed to low-T (<300 °C) serpentinisation along inner fractures and grain boundaries of olivine phenocrysts. The measured concentrations of volatile components in the melt inclusions corrected for the effects of post-entrapment crystallisation and H2O–CO2 exsolution in inclusion shrinkage bubbles are: 286–1748 μg/g CO2, 0.2–0.86 wt.% H2O, 48–82 μg/g F, 398–699 μg/g S and 132–198 μg/g Cl. They correspond to a pressure of 86±44MPa or ∼2.5-km crustal depth of olivine crystallisation. The correlations of S and, to a lesser extent, of H2O, with highly incompatible lithophile elements and the correlation of F with Cl, but no relationships of H2O with Cl, rule out shallow depth magma degassing and/or crustal contamination. Our new δ18O olivine and volatile component data combined with the existing, highly variable δ11B values for melt inclusions also support the deep mantle origin of H2O (and probably other volatiles) in the Gorgona mafic and ultramafic magmas

Always on my mind: Cross-brain associations of mental health symptoms during simultaneous parent-child scanning.

How parents manifest symptoms of anxiety or depression may affect how children learn to modulate their own distress, thereby influencing the children's risk for developing an anxiety or mood disorder. Conversely, children's mental health symptoms may impact parents' experiences of negative emotions. Therefore, mental health symptoms can have bidirectional effects in parent-child relationships, particularly during moments of distress or frustration (e.g., when a parent or child makes a costly mistake). The present study used simultaneous functional magnetic resonance imaging (fMRI) of parent-adolescent dyads to examine how brain activity when responding to each other's costly errors (i.e., dyadic error processing) may be associated with symptoms of anxiety and depression. While undergoing simultaneous fMRI scans, healthy dyads completed a task involving feigned errors that indicated their family member made a costly mistake. Inter-brain, random-effects multivariate modeling revealed that parents who exhibited decreased medial prefrontal cortex and posterior cingulate cortex activation when viewing their child's costly error response had children with more symptoms of depression and anxiety. Adolescents with increased anterior insula activation when viewing a costly error made by their parent had more anxious parents. These results reveal cross-brain associations between mental health symptomatology and brain activity during parent-child dyadic error processing