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The crystal structure of tlapallite has been determined using single-crystal X-ray diffraction and supported by electron probe micro-analysis, powder diffraction and Raman spectroscopy. Tlapallite is trigonal, space group P321, with a = 9.1219(17) Å, c = 11.9320(9) Å and V = 859.8(3) Å3, and was refined to R1 = 0.0296 for 786 reflections with I > 2σ(I). This study resulted from the discovery of well-crystallised tlapallite at the Wildcat prospect, Utah, USA. The chemical formula of tlapallite has been revised to (Ca,Pb)3CaCu6[Te4+3Te6+O12]2(Te4+O3)2(SO4)2·3H2O, or more simply (Ca,Pb)3CaCu6Te4+8Te6+2O30(SO4)2·3H2O, from H6(Ca,Pb)2(Cu,Zn)3(TeO3)4(TeO6)(SO4). The tlapallite structure consists of layers containing distorted Cu2+O6 octahedra, Te6+O6 octahedra and Te4+O4 disphenoids (which together form the new mixed-valence phyllotellurate anion [Te4+3Te6+O12]12−), Te4+O3 trigonal pyramids and CaO8 polyhedra. SO4 tetrahedra, Ca(H2O)3O6 polyhedra and H2O groups fill the space between the layers. Tlapallite is only the second naturally occurring compound containing tellurium in both the 4+ and 6+ oxidation states with a known crystal structure, the other being carlfriesite, CaTe4+2Te6+O8. Carlfriesite is the predominant secondary tellurium mineral at the Wildcat prospect. We also present an updated structure for carlfriesite, which has been refined to R1 = 0.0230 for 874 reflections with I > 2σ(I). This updated structural refinement improves upon the one reported previously by refining all atoms anisotropically and presenting models of bond valence and Te4+ secondary bonding.
Children with CHD and acquired heart disease have unique, high-risk physiology. They may have a higher risk of adverse tracheal-intubation-associated events, as compared with children with non-cardiac disease.
Materials and methods
We sought to evaluate the occurrence of adverse tracheal-intubation-associated events in children with cardiac disease compared to children with non-cardiac disease. A retrospective analysis of tracheal intubations from 38 international paediatric ICUs was performed using the National Emergency Airway Registry for Children (NEAR4KIDS) quality improvement registry. The primary outcome was the occurrence of any tracheal-intubation-associated event. Secondary outcomes included the occurrence of severe tracheal-intubation-associated events, multiple intubation attempts, and oxygen desaturation.
A total of 8851 intubations were reported between July, 2012 and March, 2016. Cardiac patients were younger, more likely to have haemodynamic instability, and less likely to have respiratory failure as an indication. The overall frequency of tracheal-intubation-associated events was not different (cardiac: 17% versus non-cardiac: 16%, p=0.13), nor was the rate of severe tracheal-intubation-associated events (cardiac: 7% versus non-cardiac: 6%, p=0.11). Tracheal-intubation-associated cardiac arrest occurred more often in cardiac patients (2.80 versus 1.28%; p<0.001), even after adjusting for patient and provider differences (adjusted odds ratio 1.79; p=0.03). Multiple intubation attempts occurred less often in cardiac patients (p=0.04), and oxygen desaturations occurred more often, even after excluding patients with cyanotic heart disease.
The overall incidence of adverse tracheal-intubation-associated events in cardiac patients was not different from that in non-cardiac patients. However, the presence of a cardiac diagnosis was associated with a higher occurrence of both tracheal-intubation-associated cardiac arrest and oxygen desaturation.
Depression and obesity are highly prevalent, and major impacts on public health frequently co-occur. Recently, we reported that having depression moderates the effect of the FTO gene, suggesting its implication in the association between depression and obesity.
To confirm these findings by investigating the FTO polymorphism rs9939609 in new cohorts, and subsequently in a meta-analysis.
The sample consists of 6902 individuals with depression and 6799 controls from three replication cohorts and two original discovery cohorts. Linear regression models were performed to test for association between rs9939609 and body mass index (BMI), and for the interaction between rs9939609 and depression status for an effect on BMI. Fixed and random effects meta-analyses were performed using METASOFT.
In the replication cohorts, we observed a significant interaction between FTO, BMI and depression with fixed effects meta-analysis (β=0.12, P = 2.7 × 10−4) and with the Han/Eskin random effects method (P = 1.4 × 10−7) but not with traditional random effects (β = 0.1, P = 0.35). When combined with the discovery cohorts, random effects meta-analysis also supports the interaction (β = 0.12, P = 0.027) being highly significant based on the Han/Eskin model (P = 6.9 × 10−8). On average, carriers of the risk allele who have depression have a 2.2% higher BMI for each risk allele, over and above the main effect of FTO.
This meta-analysis provides additional support for a significant interaction between FTO, depression and BMI, indicating that depression increases the effect of FTO on BMI. The findings provide a useful starting point in understanding the biological mechanism involved in the association between obesity and depression.
We present preliminary results of a time-dependent, three-dimensional hydrodynamic simulation of LMC-X4, an HMXB known to be undergoing RLOF. The simulation is initialized with the collapsed companion embedded in the undisturbed primary wind. The primary is in contact with the Roche surface, although no tidal stream or accretion disk is initialed; they are allowed to form independently.
Several features of general interest to disk-fed HMXBs are apparent in the simulation. First, the primary immediately develops a compressed-wind disk in the orbital plane. This may be a natural result in most disk-fed HMXBs. Fora circularized system in an orbit close enough for RLOF to take place, we may expect the primary to be in corotation. The surface velocity may then be a significant fraction of the breakup velocity, leading to a compressed-wind disk.
We present a series of time-dependent 2D and 3D numerical simulations illustrating the evolutionary sequence between high mass X-ray binaries fed by wind accretion (where the primary star sits well within its critical tidal lobe) and those fed by Roche lobe overflow (where the primary star extends out to its tidal lobe). When the primary lies well within its critical surface we find negligible tidal mass loss enhancement, and a system that is characterized by wind accretion with the development of a photoionization zone around the compact object. As the surface of the primary nears the critical surface, we observe tidally enhanced mass loss via a thin tidal stream, resulting in higher accretion wake densities. For full RLOF we observe the development of a steady accretion disk characterized by a total shadowing of the X-rays in the orbital plane.
A political spring is an abrupt, broad, sustained increase in public dissent in a state that has prohibited it, as in Czechoslovakia in 1968 or Tunisia in early 2011. Some springs produce offspring – clusters of events within neighbouring states (civic unrest, increased state repression, co-option of dissent, revolution) and among those states (intensification of international rivalries, foreign interventions). An English Spring in 1558–9 produced such a cluster in Northwestern Europe. This article addresses the underlying causal mechanism connecting springs and their offspring, rather than the related correlational question (viz. under what conditions a spring is followed by offspring). That mechanism is transnational group polarisation, or the progressive separation of preferences across a population into pro- and anti-government groups. Transnational polarisation along a pro-versus-anti-government axis is an endogenous process triggered by exogenous events, such as violence or public demonstrations that raise the status of, or threat to, one of the groups. It presents powerful actors across states with new threats and opportunities and can help explain how the Tunisian Spring of early 2011 produced throughout the Arab Middle East infectious unrest, serial repressions and reforms, heightened international tensions, and foreign interventions.
Cape Espenberg is on the farthest southwestern extent of Kotzebue Sound, Alaska, just above the Arctic Circle, and is a peninsula composed of a series of dune-covered beach ridges. As part of a larger research initiative, extensive mapping to record all cultural features and characterize the topography of approximately 1 km2 on the southeastern terminus of the cape was undertaken in 2007 and 2010. The primary purpose of this mapping was to explore the use of the cape for the past 1,200 years using one of the unique aspects of beach-ridge archaeology: horizontal stratigraphy. There were 11 intervals of beach ridge/dune development, and with the exception of one truncated ridge and the modern ridge, Thule-Iñupiaq people built semi-subterranean winter houses on each ridge. A total of 117 house depressions along with related cache pits, artifact scatters, whale bone, and hearths were identified; distribution of house forms indicate that Cape Espenberg has had an unbroken stream of cultural continuity. However, in terms of house architecture and community patterning, it appears that there has been a reduction of certain architectural components over time. Houses also occur more frequently in isolated contexts. Both aspects are coincident with the onset of the Little Ice Age.
Any serious treatment of how regions become more cooperative and peaceful must consider the commercial-liberal thesis. The thesis asserts that economic links among states alter those states’ incentives and hence their actions and interactions. National economies may be linked in various ways, including trade in goods and services, investment, borrowing and lending, and guest workers. The welfare of one state may come to depend to some extent upon links with another; when two states depend on each other – when bilateral trade, for example is so high that its disruption would harm both states – the relationship is one of interdependence. The commercial-liberal claim is that economic interdependence pacifies relations among states. With some refinement, discussed below, the claim should be applicable not just to pairs of states but also to regions as T. V. Paul defines them in this volume – that is, as “clusters of states that are proximate to each other and are interconnected in spatial, cultural, and ideational terms in a significant and distinguishable manner.”
The interdependence thesis is widely held, intuitive (to some), and empirically supported. It also is relevant as never before, as economic barriers among states around the world are so low that we speak of an era of “globalization.” Surely, many say, at least one cause of the extraordinary peace in Europe since 1945 is the tight economic ties between the economies of member states: the ongoing free movement of goods, capital, and labor, and more recently the single currency most members use, the harmonization of product regulation and labor standards, and so on. Surely, at least most of these would add, this sort of economic integration is one of the keys to a peaceful future in East Asia. Surely the Middle East would be more peaceful and cooperative if its national economies likewise became more integrated – if Israel, Saudi Arabia, Iran, and so forth, traded and invested extensively in one another.
To assess the quality of imaging modalities of a new micro multiplane transoesophageal echocardiogram probe.
This is a prospective study of micro transoesophageal echocardiogram S8-3t probe used at a single institution between 15 December, 2009 and 15 March, 2010. The images were compared with standard paediatric or adult probes where possible. Assessors prospectively rated imaging quality – two dimensional, colour flow imaging, pulse wave, and continuous wave Doppler – with a subjective 4-point scale (1 = poor to 4 = excellent).
A total of 24 studies were performed on 23 patients, with a median weight = 11.7 kilograms (2.6–72 kilograms) and a median age of 3 years (0.16–60 years). Of the 23 patients, one neonate (2.8 kilograms) had transient bradycardia on probe insertion. Imaging in patients less than 10 kilograms was of full diagnostic value and new information was obtained in eight out of ten patients. Pulse wave and continuous wave Doppler was consistently good across all weight groups. There were high frame rates and good imaging quality to a depth of 4–6 centimetres in all studies. A comparison with a larger alternative probe was available for 12 studies (weight 11.9–72 kilograms). The median micro transoesophageal two-dimensional image quality score was 3 (2–4) and 4 (3–4) with the comparative probe. For the 10- to 30-kilogram group, image quality with the micro transoesophageal echocardiogram probe was judged as inferior to larger standard probes. Adult sized patients had good imaging of near the field, allowing guidance for percutaneous device closure of the atrial septum.
The micro multiplane transoesophageal echocardiogram probe provides imaging of diagnostic quality in neonates. In larger patients, it offers good imaging of near field structures. In the intermediate-sized child (10–30 kilograms), standard paediatric probes provide better imaging.
Nanocrystalline silicon (n-Si) is formed in a silicon dioxide thin-film matrix by ion implantation followed by thermal annealing in forming gas at 1100 °C for 1 hour. The ion implantation is performed using multiple implants with different implantation energies and doses to create a quasi-flat concentration of silicon atoms throughout the silicon dioxide film. These samples are then analyzed using spectroscopic ellipsometry to characterize their linear optical properties. Implantations with small doses (5 × 1020 Si atoms/cm3) increase the refractive index by a small amount (δn∼0.006 at 600nm), while implantations with moderate dose (5 × 1021 Si atoms/cm3) have a larger increase in refractive index and exhibit optical absorption above ∼1.9 eV (650 nm).
Can we predict accurately a state's behavior from its international power ranking? May we safely predict, with Thucydides' Athenians, that “the strong do what they can and the weak suffer what they must?” Not all structural realists answer in the affirmative. Waltz's denial is the most prominent: his neorealism, he asserts, is a theory of international outcomes, not of foreign policy. It cannot predict when A will seek to ally with state B, but only when an A+B alliance will form. A systemic theory predicts systemic outcomes. Unit-level outcomes, such as alliance seeking, require unit-level explanations such as domestic politics or the traits of individual leaders.
Most structural realists find Waltz, in this one aspect, insufficiently ambitious. Elman, Copeland, Mearsheimer, and others insist that international structure is strong enough to constrain, and hence explain, states' foreign policies as well. These scholars appear on firm ground: if a balance of power entails states' acting, intentionally or not, so as to form that balance, then it follows that a theory predicting that balance must predict that states will act so as to bring it about. Indeed, Waltz himself makes claims about individual states' policies as vindication for his theory; thus pressure from the international system caused the young Soviet Union to change from a revolutionary, disruptive power to a pragmatic one that aligned with Weimar Germany in 1922.
Our aims were to estimate the prevalence of increased nuchal translucency in fetuses with a normal karyotype that were subsequently diagnosed with congenital cardiac disease on fetal echocardiography, and to assess whether there is a link between increased nuchal translucency and specific congenital cardiac malformations.
We reviewed all patients referred to King’s College Hospital and the Evelina Children’s Hospital in London for fetal echocardiography between January 1998 and December 2007. We investigated the proportion of chromosomally normal fetuses with congenitally malformed hearts in which nuchal thickness was increased, both overall and with specific defects.
We indentified 2133 fetuses with congenital cardiac disease by prenatal echocardiography. Of those, 707 were excluded due to abnormal karyotype, and 690 were excluded due to unknown karyotype. The remaining 736 were eligible for inclusion. Among 481 fetuses with documented congenital cardiac disease and normal chromosomes, making up 23% of the overall cohort, 224 had increased nuchal thickness defined as equal or greater than 2.5 millimetres, this being 0.47 of the inclusive cohort, with 95% confidence intervals from 0.42 to 0.51. These proportions were significantly higher than the expected proportion of the normal population, which was 0.05 (p < 0.001). The only diagnosis for which the proportion of fetuses with nuchal translucency measurement equal or greater than 2.5 millimetres was higher than the others was atrioventricular septal defect, with 0.62 of this cohort having abnormal values, with 95% confidence intervals from 0.47 to 0.77 (p = 0.038).
We found that nearly half of prenatally diagnosed fetuses with congenitally malformed hearts, when examined ultrasonically in the first or early-second trimester, had increased nuchal thickness. We recommend, therefore, referral of all fetuses with increased nuchal translucency for fetal echocardiography.