Context.
Characterising the large-scale structure in the Universe from present times to the high redshift epoch of reionisation is essential to constraining the cosmology, the history of star ...formation, and reionisation, to measuring the gas content of the Universe, and to obtaining a better understanding of the physical processes that drive galaxy formation and evolution. Using the integrated emission from unresolved galaxies or gas clouds, line intensity mapping (LIM) provides a new observational window to measure the larger properties of structures. This very promising technique motivates the community to plan for LIM experiments.
Aims.
We describe the development of a large field-of-view instrument, named CONCERTO (for CarbON CII line in post-rEionisation and ReionisaTiOn epoch), operating in the range 130–310 GHz from the APEX 12-m telescope (5100 m above sea level). CONCERTO is a low-resolution spectrometer based on the lumped element kinetic inductance detectors (LEKID) technology. Spectra are obtained using a fast Fourier transform spectrometer (FTS), coupled to a dilution cryostat with a base temperature of 0.1 K. Two two kilo-pixel arrays of LEKID are mounted inside the cryostat that also contains the cold optics and the front-end electronics.
Methods.
We present, in detail, the technological choices leading to the instrumental concept, together with the design and fabrication of the instrument and preliminary laboratory tests on the detectors. We also give our best estimates for CONCERTO sensitivity and give predictions for two of the main scientific goals of CONCERTO, that is, a CII-intensity mapping survey and observations of galaxy clusters.
Results.
We provide a detailed description of the instrument design. Based on realistic comparisons with existing instruments developed by our group (NIKA, NIKA2, and KISS), and on the laboratory characterisation of our detectors, we provide an estimate for CONCERTO sensitivity on the sky. Finally, we describe, in detail, two of the main scientific goals offered by CONCERTO at APEX.
Although methods for a periodic perforation and heteroatom doping of graphene sheets have been developed, patterning closely spaced holes on the nanoscale in graphene nanoribbons is still a ...challenging task. In this work, nitrogen-doped porous graphene nanoribbons (N-GNRs) were synthesized on Ag(111) using a silver-assisted Ullmann polymerization of brominated tetrabenzophenazine. Insights into the hierarchical reaction pathways from single molecules toward the formation of one-dimensional organometallic complexes and N-GNRs are gained by a combination of scanning tunneling microscopy (STM), atomic force microscopy (AFM) with CO-tip, scanning tunneling spectroscopy (STS), and density functional theory (DFT).
Introduction Les différents facteurs pronostics du glioblastome commencent à être bien connus. L’impact majeur de l’âge, des scores de performance et de la résection chirurgicale a été largement ...démontré. Cependant, l’agressivité de la tumeur, caractérisée par son délai de récidive, est encore assez peu étudiée et l’évolution que va suivre un patient reste en partie inconnue. Matériels et méthode Nous avons appliqué, sur l’effectif 26 981 de l’EORTC, une méthode de statistique appelée CART (Classification And Regression Trees) pour révéler les facteurs cliniques qui permettent de classer les patients en sous-groupes selon leur délai de récidive. La survie après récidive a été comparée par la méthode de Kaplan–Meier et le test des Log-rangs. Résultats Le WHO PS et l’âge à la première intervention permettent de former trois groupes de patients ayant un risque relatif de récidive de 0,6 pour les patients avec un WHO PS de 0 ou 1 et âgés de moins de 47,5 ans, 1,1 pour les patients avec un WHO PS de 0 ou 1 et âgés de plus de 47,5 ans, et de 2,2 pour les patients avec un WHO PS de 2 ou 3. De plus, des analyses de survie après récidive ont montré que les patients avec un faible risque de récidive survivent plus longtemps que les patients possédant un risque de récidive élevé. Conclusion Trois groupes de patients ayant des risques de récidive différents ont été mis en évidence. Par la suite, ces groupes formés permettront de comparer l’expression de marqueurs biologiques entre des tumeurs d’agressivités différentes, afin d’identifier des marqueurs de l’agressivité du glioblastome.
At least five animal phyla exhibit spiralian development, which is characterized by striking similarities in the geometry of the early cleavage pattern and the fate map of the blastula, along with ...similarities in larval morphology. Recent advances in reconstructing the phylogeny of spiralians and their relatives suggest that the common ancestor of a large clade of protostome phyla known as the Lophotrochozoa had spiralian development. In this minireview, I describe characteristics of spiralian development and some recent insights into its mechanisms and evolution.
The Global Ozone Monitoring Instrument (GOME) was launched on European Space Agency's ERS‐2 platform in April 1995. The GOME data processor (GDP) operational retrieval algorithm has generated total ...ozone columns since July 1995. In 2004 the GDP system was given a major upgrade to version 4.0, a new validation was performed, and the 10‐year GOME level 1 data record was reprocessed. In two papers, we describe the GDP 4.0 retrieval algorithm and present an error budget and sensitivity analysis (paper 1) and validation of the GDP total ozone product and the overall accuracy of the entire GOME ozone record (paper 2). GDP 4.0 uses an optimized differential optical absorption spectroscopy (DOAS) algorithm, with air mass factor (AMF) conversions calculated using the radiative transfer code linearized discrete ordinate radiative transfer (LIDORT). AMF computation is based on the TOMS version 8 ozone profile climatology, classified by total column, and AMFs are adjusted iteratively to reflect the DOAS slant column result. GDP 4.0 has improved wavelength calibration and reference spectra and includes a new molecular Ring correction to deal with distortion of ozone absorption features due to inelastic rotational Raman scattering effects. Preprocessing for cloud parameter estimation in GDP 4.0 is done using two new cloud correction algorithms: OCRA and ROCINN. For clear and cloudy scenes the precision of the ozone column product is better than 2.4 and 3.3%, respectively, for solar zenith angles up to 80°. Comparisons with ground‐based data are generally at the 1–1.5% level or better for all regions outside the poles.
The high thermal conductivity of graphene and few-layer graphene undergoes severe degradations through contact with the substrate. Here we show experimentally that the thermal management of a micro ...heater is substantially improved by introducing alternative heat-escaping channels into a graphene-based film bonded to functionalized graphene oxide through amino-silane molecules. Using a resistance temperature probe for in situ monitoring we demonstrate that the hotspot temperature was lowered by ∼28 °C for a chip operating at 1,300 W cm(-2). Thermal resistance probed by pulsed photothermal reflectance measurements demonstrated an improved thermal coupling due to functionalization on the graphene-graphene oxide interface. Three functionalization molecules manifest distinct interfacial thermal transport behaviour, corroborating our atomistic calculations in unveiling the role of molecular chain length and functional groups. Molecular dynamics simulations reveal that the functionalization constrains the cross-plane phonon scattering, which in turn enhances in-plane heat conduction of the bonded graphene film by recovering the long flexural phonon lifetime.
Among animals, diploblasts contain two germ layers, endoderm and ectoderm, while triploblasts have a distinct third germ layer called the mesoderm. Spiralians are a group of triploblast animals that ...have highly conserved development: they share the distinctive spiralian cleavage pattern as well as a unique source of mesoderm, the ectomesoderm. This population of mesoderm is distinct from endomesoderm and is considered a hallmark of spiralian development, but the regulatory network that drives its development is unknown. Here we identified ectomesoderm-specific genes in the mollusc Tritia (aka Ilyanassa) obsoleta through differential gene expression analyses comparing control and ectomesoderm-ablated embryos, followed by in situ hybridization of identified transcripts. We identified a Tritia serpin gene (ToSerpin1) that appears to be specifically expressed in the ectomesoderm of the posterior and head. Ablation of the 3a and 3b cells, which make most of the ectomesoderm, abolishes ToSerpin1 expression, consistent with its expression in these cells. Morpholino knockdown of ToSerpin1 causes ectomesoderm defects, most prominently in the muscle system of the larval head. This is the first gene identified that is specifically implicated in spiralian ectomesoderm development.
•A conserved feature of spiralians is ectomesoderm, a second source of mesoderm.•To find ectomesoderm-specific genes, we carried out RNA-seq after ablation of its precursor cells.•ToSerpin1 appeared to be expressed in ectomesoderm, and its expression was lost after ectomesoderm ablation.•Knockdown caused defects in the head musculature, the main ectomesoderm-derived organ.•This is the first gene that has been functionally implicated in ectomesoderm development.
We have developed an efficient simulation tool 'GOLLUM' for the computation of electrical, spin and thermal transport characteristics of complex nanostructures. The new multi-scale, multi-terminal ...tool addresses a number of new challenges and functionalities that have emerged in nanoscale-scale transport over the past few years. To illustrate the flexibility and functionality of GOLLUM, we present a range of demonstrator calculations encompassing charge, spin and thermal transport, corrections to density functional theory such as local density approximation +U (LDA+U) and spectral adjustments, transport in the presence of non-collinear magnetism, the quantum Hall effect, Kondo and Coulomb blockade effects, finite-voltage transport, multi-terminal transport, quantum pumps, superconducting nanostructures, environmental effects, and pulling curves and conductance histograms for mechanically-controlled break-junction experiments.
The relationship between protonmotive force and superoxide production by mitochondria is poorly understood. To address this issue, the rate of superoxide production from complex I of rat skeletal ...muscle mitochondria incubated under a variety of conditions was assessed. By far, the largest rate of superoxide production was from mitochondria respiring on succinate; this rate was almost abolished by rotenone or piericidin, indicating that superoxide production from complex I is large under conditions of reverse electron transport. The high rate of superoxide production by complex I could also be abolished by uncoupler, confirming that superoxide production is sensitive to protonmotive force. It was inhibited by nigericin, suggesting that it is more dependent on the pH gradient across the mitochondrial inner membrane than on the membrane potential. These effects were examined in detail, leading to the conclusions that the effect of protonmotive force was mostly direct, and not indirect through changes in the redox state of the ubiquinone pool, and that the production of superoxide by complex I during reverse electron transport was at least 3-fold more sensitive to the pH gradient than to the membrane potential.
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