The Leiden/Argentine/Bonn (LAB) Survey of Galactic HI: Final data release of the combined LDS and IAR surveys with improved stray-radiation corrections

We present the final data release of observations of lambda 21-cm emission from Galactic neutral hydrogen over the entire sky, merging the Leiden/Dwingeloo Survey (LDS: Hartmann & Burton, 1997) of the sky north of delta = -30 deg with the Instituto Argentino de Radioastronomia Survey (IAR: Arnal et al., 2000, and Bajaja et al., 2005) of the sky south of delta = -25 deg. The angular resolution of the combined material is HPBW ~ 0.6 deg. The LSR velocity coverage spans the interval -450 km/s to +400 km/s, at a resolution of 1.3 km/s. The data were corrected for stray radiation at the Institute for Radioastronomy of the University of Bonn, refining the original correction applied to the LDS. The rms brightness-temperature noise of the merged database is 0.07 - 0.09 K. Residual errors in the profile wings due to defects in the correction for stray radiation are for most of the data below a level of 20 - 40 mK. It would be necessary to construct a telescope with a main beam efficiency of eta_{MB} > 99% to achieve the same accuracy. The merged and refined material entering the LAB Survey of Galactic HI is intended to be a general resource useful to a wide range of studies of the physical and structural characteristices of the Galactic interstellar environment. The LAB Survey is the most sensitive Milky Way HI survey to date, with the most extensive coverage both spatially and kinematically.Comment: 9 pages, 5 figures, accepted for publication by Astronomy & Astrophysic

Newton additive and multiplicative Schwarz iterative methods

Convergence properties are presented for Newton additive and multiplicative Schwarz (AS and MS) iterative methods for the solution of nonlinear systems in several variables. These methods consist of approximate solutions of the linear Newton step using either AS or MS iterations, where overlap between subdomains can be used. Restricted versions of these methods are also considered. These Schwarz methods can also be used to precondition a Krylov subspace method for the solution of the linear Newton steps. Numerical experiments on parallel computers are presented, indicating the effectiveness of these methods.The Spanish Ministry of Science and Education (TIN2005-09037-C02-02); Universidad de Alicante (VIGROB-020); the U.S. Department of Energy (DE-FG02-05ER25672)

Closedness of star products and cohomologies

We first review the introduction of star products in connection with deformations of Poisson brackets and the various cohomologies that are related to them. Then we concentrate on what we have called ``closed star products" and their relations with cyclic cohomology and index theorems. Finally we shall explain how quantum groups, especially in their recent topological form, are in essence examples of star products.Comment: 16 page

Monte Carlo Calculations on Electron Backscattering in Amorphous or Polycrystalline Targets

We propose an application of the Monte Carlo method in the field of backscattering. The results obtained for incident electron energies ranging from 0.3 to 3 MeV and for targets of Al, Cu, Ag and Au are compared with experimental values from several sources. An electron travelling through matter undergoes successive collisions between which it is assumed to travel in a straight line. In our case, we consider the elementary process of interaction electron-nucleus; we have used analytical models for the scattering cross-sections. In order to follow the electron through the specimen, we divide the real trajectory into elements of length much smaller than the mean free path. Pseudo-random number process permits us to determine whether or not an interaction occurs, also the type of interaction. For the energy losses, we introduced a relation derived from Landau\u27s theory. We then followed the electron until it is emerged from the material or halted. The backscattering coefficients obtained for thin and thick targets as a function of the incident electron energy are in good agreement with the experimental data. We have introduced the depth distribution function of the backscattered electrons, which allows us to test the predictions of various theoretical models proposed by other authors

Automatic Detection of Expanding HI Shells Using Artificial Neural Networks

The identification of expanding HI shells is difficult because of their variable morphological characteristics. The detection of HI bubbles on a global scale therefore never has been attempted. In this paper, an automatic detector for expanding HI shells is presented. The detection is based on the more stable dynamical characteristics of expanding shells and is performed in two stages. The first one is the recognition of the dynamical signature of an expanding bubble in the velocity spectra, based on the classification of an artificial neural network. The pixels associated with these recognized spectra are identified on each velocity channel. The second stage consists in looking for concentrations of those pixels that were firstly pointed out, and to decide if they are potential detections by morphological and 21-cm emission variation considerations. Two test bubbles are correctly detected and a potentially new case of shell that is visually very convincing is discovered. About 0.6% of the surveyed pixels are identified as part of a bubble. These may be false detections, but still constitute regions of space with high probability of finding an expanding shell. The subsequent search field is thus significantly reduced. We intend to conduct in the near future a large scale HI shells detection over the Perseus Arm using our detector.Comment: 39 pages, 11 figures, accepted by PAS

Refining and mining the phylogeny of Glycoside Hydrolase Family 74 via structure-function analysis

Sustained interest in the use of carbohydrates from plant cell walls, coupled with the advancement of high-throughput (meta)genomic sequencing, has led to the discovery of an overwhelming number of predicted carbohydrate-active enzymes (CAZymes) in the last decade. The CAZy database provides a powerful framework for the study of CAZymes, including Glycoside Hydrolases (GHs), by enabling the prediction of key enzyme features such as 3-D fold, catalytic residues, catalytic mechanism, and – with certain limitations – substrate specificity. Refined phylogenetic analyses contribute to increasing the accuracy of predictions by further clustering proteins into sub-families (1, 2). However, reliable prediction of substrate specificity for newly discovered GHs remains a challenge due to a general lack of in-depth biochemical and structural characterization across the existing phylogenetic diversity. Glycoside Hydrolase family 74 (GH74) comprises endo-glucanases, many of which have predominant activity toward xyloglucan, a highly branched plant cell wall matrix glycan. To better delineate overall substrate specificity, backbone cleavage position, and endo-dissociative vs. endo-processive hydrolytic modes, a broad-based structure-function analysis of GH74 guided by molecular phylogeny was performed. Seven sub-families were discerned, which grouped nearly 40% of the current \u3e300 GH74 sequences in the public CAZy database. Thirty one GH74 members were targeted for further investigation based on their phylogenetic position and unique primary structural features identified during manual curation. The biochemical characterization of 18 recombinant GH74s revealed key sequence features governing xyloglucan backbone cleavage sites and highlighted clear phylogenetic differences between endo-dissociative and endo-processive enzymes. Commensurate with previous studies (3), site-directed mutagenesis of key active-site tryptophan residues defined their essential contributions to processivity on the soluble polysaccharide substrate. Six new GH74 tertiary structures (apo and/or in complex with xylogluco-oligosaccharides) were determined that further resolved the contribution of active-site loops in modulating the size of oligosaccharide products released by individual subfamily members. Refining the correlation between phylogeny and enzyme structure-function properties in GH74 significantly enhances the prediction of catalytic ability, highlights key steps in the evolution of function in the family, and ultimately informs applications in biomass conversion. 1. Stam MR, Danchin EGJ, Rancurel C, Coutinho PM, Henrissat B. 2006. Dividing the large glycoside hydrolase family 13 into subfamilies: towards improved functional annotations of alpha-amylase-related proteins. Protein Engineering Design & Selection 19:555-562. 2. Aspeborg H, Coutinho PM, Wang Y, Brumer H, Henrissat B. 2012. Evolution, substrate specificity and subfamily classification of glycoside hydrolase family 5 (GH5). Bmc Evolutionary Biology 12. 3. Matsuzawa T, Saito Y, Yaoi K. 2014. Key amino acid residues for the endo-processive activity of GH74 xyloglucanase. FEBS Lett 588:1731-8

Mechanisms underlying cytotoxicity induced by engineered nanomaterials: a review of in vitro studies

Engineered nanomaterials are emerging functional materials with technologically interesting properties and a wide range of promising applications, such as drug delivery devices, medical imaging and diagnostics, and various other industrial products. However, concerns have been expressed about the risks of such materials and whether they can cause adverse effects. Studies of the potential hazards of nanomaterials have been widely performed using cell models and a range of in vitro approaches. In the present review, we provide a comprehensive and critical literature overview on current in vitro toxicity test methods that have been applied to determine the mechanisms underlying the cytotoxic effects induced by the nanostructures. The small size, surface charge, hydrophobicity and high adsorption capacity of nanomaterial allow for specific interactions within cell membrane and subcellular organelles, which in turn could lead to cytotoxicity through a range of different mechanisms. Finally, aggregating the given information on the relationships of nanomaterial cytotoxic responses with an understanding of its structure and physicochemical properties may promote the design of biologically safe nanostructures

Do Multinational enterprises push up wages of domestic firms in the Italian Manufacturing sector?

This paper analyzes the effects of foreign direct investment on wages paid by domestic firms in the Italian manufacturing sector over the period 2002–2007. In particular, the authors investigate the im-pact of multinational enterprises on wages paid by local firms which operate in the same industry, known and horizontal wage spillovers, or have linkages with multinational enterprises in both downstream and upstream industries, known as vertical wage spillovers. By using a large panel dataset, consisting of 551,000 observations, the authors find evidence of wage spillovers only at inter-industry level and, more specifically, for those firms who supply their goods to multinational enterprises, described as backward wage spillovers. Moreover, findings suggest that the wage spillover effect is strongly affected by the technological gap between local and foreign firms: only workers employed in domestic firms with a low-medium technological absorptive capacity seem to benefit from the presence of multinational enterprises in terms of higher wages

Building a Practical Natural Laminar Flow Design Capability

A preliminary natural laminar flow (NLF) design method that has been developed and applied to supersonic and transonic wings with moderate-to-high leading-edge sweeps at flight Reynolds numbers is further extended and evaluated in this paper. The modular design approach uses a knowledge-based design module linked with different flow solvers and boundary layer stability analysis methods to provide a multifidelity capability for NLF analysis and design. An assessment of the effects of different options for stability analysis is included using pressures and geometry from an NLF wing designed for the Common Research Model (CRM). Several extensions to the design module are described, including multiple new approaches to design for controlling attachment line contamination and transition. Finally, a modification to the NLF design algorithm that allows independent control of Tollmien-Schlichting (TS) and cross flow (CF) modes is proposed. A preliminary evaluation of the TS-only option applied to the design of an NLF nacelle for the CRM is performed that includes the use of a low-fidelity stability analysis directly in the design module

The Leiden/Argentine/Bonn (LAB) survey of Galactic HI : Final data release of the combined IDS and IAR surveys with improved stray-radiation corrections

We present the final data release of observations of λ21-cm emission from Galactic neutral hydrogen over the entire sky, merging the Leiden/Dwingeloo Survey (LDS: Hartmann & Burton 1997, Atlas of Galactic Neutral Hydrogen) of the sky north of δ = -30° with the Instituto Argentino de Radioastronomía Survey (IAR: Arnal et al. 2000, A&AS, 142, 35; and Bajaja et al. 2005, A&A, 440, 767) of the sky south of δ= -25°. The angular resolution of the combined material is HPBW ∼ 0°.6. The LSR velocity coverage spans the interval -450 km s-1 to +400 km s-1, at a resolution of 1.3 km s-1. The data were corrected for stray radiation at the Institute for Radioastronomy of the University of Bonn, refining the original correction applied to the LDS. The rms brightness-temperature noise of the merged database is 0.07-0.09 K. Residual errors in the profile wings due to defects in the correction for stray radiation are for most of the data below a level of 20-40 mK. It would be necessary to construct a telescope with a main beam efficiency of ηMB ≳ 99% to achieve the same accuracy. The merged and refined material entering the LAB Survey of Galactic H I is intended to be a general resource useful to a wide range of studies of the physical and structural characteristices of the Galactic interstellar environment. The LAB Survey is the most sensitive Milky Way H I survey to date, with the most extensive coverage both spatially and kinematically.Instituto Argentino de RadioastronomíaFacultad de Ciencias Astronómicas y Geofísica