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In-vessel plasma facing components in fusion reactors such as ITER and DEMO experience high thermal loads and require active cooling, for which water is one possible coolant. The solution where plasma facing components utilise tungsten blocks as sacrificial armour has a joint internal structure of cooling tubes made from the copper base (∼99 % Cu) alloy CuCrZr. This paper concerns the testing of CuCrZr tubes with respect to flow-assisted corrosion (FAC) at water velocity in the range 8–10 m/s and temperature in the range 150 °C–250 °C. The FAC rate was evaluated by gravimetry, microscopy, and sampling of the water from the re-circulating test system. When the electrochemical potential of the CuCrZr specimens was kept in the reducing range where Cu is thermodynamically stable as a metal, no FAC could be observed on the specimens. At electrochemical potentials that promotes oxidation of Cu through presence of an oxidizer the FAC rate of a straight CuCrZr tube was estimated to be in the order of 400 µm per full power year.

El presente artículo analiza las diversas relaciones intermediales entre los videojuegos y el arte pictórico. El método empleado para la investigación es el estudio de caso múltiple, permitiéndonos abordar ampliamente este fenómeno. Los resultados obtenidos reflejan la permeabilidad de los videojuegos con el arte pictórico, en concreto, mediante procesos de hibridación, la activación de las obras como elementos de juego o sujetos y la creación de espacios pictóricos dentro de la imagen videolúdica.

Las propiedades elásticas de la familia de los minerales isoestructurales Cu3VSe4, Cu3NbSe4 y Cu3TaSe4 han sido calculadas por primera vez usandoel estado del arte en cálculos atomísticos de primeros-principios, utilizandola Teoría de los Funcionales de la Densidad y la Aproximación del Gradiente Generalizado para el funcional de la energía de intercambio-correlación. Laspropiedades elásticas calculadas son el módulo volumétrico (B), las constantes elásticas (c11, c12 y c44), el factor de anisotropía de Zener (A), el módulo de cizalladura isotrópico (G), el módulo de Young (Y), y la razón de Poisson(ν). A través de estas cantidades también hemos calculado otras propiedades termodinámicas tales como la velocidad promedio del sonido transversal (st) y longitudinal (sl) y la temperatura de Debye (ΘD). Los valores calculados de B, c11, c12 y c44, G, Y , y ν nos llevan a la conclusión que estos compuestosson compresibles, frágiles y quebradizos. PACS: 91.60.Ba

Due to ethical and logistical concerns it is common for data monitoring committees to periodically monitor accruing clinical trial data to assess the safety, and possibly efficacy, of a new experimental treatment. When formalized, monitoring is typically implemented using group sequential methods. In some cases regulatory agencies have required that primary trial analyses should be based solely on the judgment of an independent review committee (IRC). The IRC assessments can produce difficulties for trial monitoring given the time lag typically associated with receiving assessments from the IRC. This results in a missing data problem wherein a surrogate measure of response may provide useful information for interim decisions and future monitoring strategies. In this paper, we present statistical tools that are helpful for monitoring a group sequential clinical trial with missing IRC data. We illustrate the proposed methodology in the case of binary endpoints under various missingness mechanisms including missing completely at random assessments and when missingness depends on the IRC’s measurement.

In this paper we demonstrate a technique that can create non-equilibrium vortex configurations with almost arbitrary charge and geometry in a Bose-Einstein condensate. We coherently transfer orbital angular momentum from a holographically generated light beam to a 87Rb condensate using a two-photon stimulated Raman process. Using matter wave interferometry, we verify the phase pattern imprinted onto the atomic wave function for a single vortex and a vortex-antivortex pair. In addition to their phase winding, the vortices created with this technique have an associated hyperfine spin texture., Physics

Quantum gases in optical lattices offer an opportunity to experimentally realize and explore condensed matter models in a clean, tunable system. We used single atom–single lattice site imaging to investigate the Bose-Hubbard model on a microscopic level. Our technique enables space- and time-resolved characterization of the number statistics across the superfluid–Mott insulator quantum phase transition. Site-resolved probing of fluctuations provides us with a sensitive local thermometer, allows us to identify microscopic heterostructures of low-entropy Mott domains, and enables us to measure local quantum dynamics, revealing surprisingly fast transition time scales. Our results may serve as a benchmark for theoretical studies of quantum dynamics, and may guide the engineering of low-entropy phases in a lattice., Physics

Recent years have seen tremendous progress in creating complex atomic many-body quantum systems. One approach is to use macroscopic, effectively thermodynamic ensembles of ultracold atoms to create quantum gases and strongly correlated states of matter, and to analyze the bulk properties of the ensemble. For example, bosonic and fermionic atoms in a Hubbard regime optical lattice 1, 2, 3, 4, 5 allow experimenters to carry out quantum simulations of solid state models 6, thereby addressing fundamental questions of condensed matter physics. The opposite approach is to build up microscopic quantum systems atom by atom – with complete control over all degrees of freedom 7, 8, 9. The atoms or ions act as qubits and allow experimenters to realize quantum gates with the goal of creating highly controllable quantum information systems. Until now, the macroscopic and microscopic strategies have been fairly disconnected. Here, we present a “quantum gas microscope” that bridges the two approaches, realizing a system where atoms of a macroscopic ensemble are detected individually and a complete set of degrees of freedom of each of them is determined through preparation and measurement. By implementing a high-resolution optical imaging system, single atoms are detected with near-unity fidelity on individual sites of a Hubbard regime optical lattice. The lattice itself is generated by projecting a holographic mask through the imaging system. It has an arbitrary geometry, chosen to support both strong tunnel coupling between lattice sites and strong on-site confinement. On one hand, this new approach can be used to directly detect strongly correlated states of matter. In the context of condensed matter simulation, this corresponds to the detection of individual electrons in the simulated crystal with atomic resolution. On the other hand, the quantum gas microscope opens the door for the addressing and readout of large-scale quantum information systems with ultracold atoms., Physics

We demonstrate the realization of a two-dimensional (2D) quantum gas in a smooth optical surface trap. Using a combination of evanescent wave, standing wave, and magnetic potentials, we create a long-lived quantum gas deep in the 2D regime at a distance of a few microns from a glass surface. To realize a system suitable for many-body quantum simulation, we introduce methods such as broadband “white” light to create evanescent and standing waves to realize a smooth potential with a trap frequency aspect ratio of 300:1:1. We are able to detect phase fluctuations and vortices, and we demonstrate cooling to degeneracy and low disorder in the 2D configuration., Physics

DNA mismatch repair suppresses gastrointestinal tumorgenesis. Four mammalian E. coli MutL homologues heterodimerize to form three distinct complexes: MLH1/PMS2, MLH1/MLH3, and MLH1/PMS1. To understand the mechanistic contributions of MLH3 and PMS2 in gastrointestinal tumor suppression, we generated \(Mlh3^{−/−}\);\(Apc^{1638N}\) and \(Mlh3^{−/−}\);\(Pms2^{−/−}\);\(Apc^{1638N}\) (MPA) mice. Mlh3 nullizygosity significantly increased Apc frameshift mutations and tumor multiplicity. Combined Mlh3;Pms2 nullizygosity further increased Apc base-substitution mutations. The spectrum of MPA tumor mutations was distinct from that observed in \(Mlh1^{−/−}\);\(Apc^{1638N}\) mice, implicating the first potential role for MLH1/PMS1 in tumor suppression. Because Mlh3;Pms2 deficiency also increased gastrointestinal tumor progression, we used array-CGH to identify a recurrent tumor amplicon. This amplicon contained a previously uncharacterized Transducin enhancer of Split (Tle) family gene, Tle6-like. Expression of Tle6-like, or the similar human TLE6D splice isoform in colon cancer cells increased cell proliferation, colony-formation, cell migration, and xenograft tumorgenicity. Tle6-like;TLE6D directly interact with the gastrointestinal tumor suppressor RUNX3 and antagonize RUNX3 target transactivation. TLE6D is recurrently overexpressed in human colorectal cancers and TLE6D expression correlates with RUNX3 expression. Collectively, these findings provide important insights into the molecular mechanisms of individual MutL homologue tumor suppression and demonstrate an association between TLE mediated antagonism of RUNX3 and accelerated human colorectal cancer progression.